TY  - DATA
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
AU  - Bošković, Jakša
AU  - Baranac-Stojanović, Marija
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/5846
AB  - We present the green, highly atom-economical, solid-state silica gel-catalyzed synthesis of polysubstituted 1,4- and 1,2-dihydropyridines (DHPs) from commercially available materials, amines and ethyl propiolate. The DHP skeleton was assembled by heating the reactants and silica gel in a closed vessel. Aliphatic amines provided 1,4-isomers as the main or only DHP products, but the reactions of aromatic amines yielded a mixture of 1,4- and 1,2-isomers. To the best of our knowledge, this is the first example of the formation of a 1,2-DHP structure by the reaction of an amine with propiolic ester. Addition of 1 mass percent of H2SO4 to silica gel shifted the product distribution to 1,4-DHP as the main or the only isomer obtained. Experimental and theoretical analyses led to the identification of two key intermediates en route to DHPs and the explanation of the observed regioisomeric ratios. 1,2-DHPs show blue-cyan fluorescence in MeOH with the quantum yield Φ = 0.10–0.22 relative to quinine sulfate Φ = 0.58 and 1,4-DHPs show blue-violet fluorescence with Φ = 0.09–0.81.
PB  - Royal Society of Chemistry
T2  - Organic & Biomolecular Chemistry
T1  - Supplementary material for: Aleksić, J., Stojanović, M., Bošković, J.,& Baranac-Stojanović, M.. (2023). Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry
Royal Society of Chemistry., 21(6), 1187-1205.
https://doi.org/10.1039/D2OB02119F
VL  - 21
IS  - 6
UR  - https://hdl.handle.net/21.15107/rcub_cherry_5846
ER  - 

@misc{
author = "Aleksić, Jovana and Stojanović, Milovan and Bošković, Jakša and Baranac-Stojanović, Marija",
abstract = "We present the green, highly atom-economical, solid-state silica gel-catalyzed synthesis of polysubstituted 1,4- and 1,2-dihydropyridines (DHPs) from commercially available materials, amines and ethyl propiolate. The DHP skeleton was assembled by heating the reactants and silica gel in a closed vessel. Aliphatic amines provided 1,4-isomers as the main or only DHP products, but the reactions of aromatic amines yielded a mixture of 1,4- and 1,2-isomers. To the best of our knowledge, this is the first example of the formation of a 1,2-DHP structure by the reaction of an amine with propiolic ester. Addition of 1 mass percent of H2SO4 to silica gel shifted the product distribution to 1,4-DHP as the main or the only isomer obtained. Experimental and theoretical analyses led to the identification of two key intermediates en route to DHPs and the explanation of the observed regioisomeric ratios. 1,2-DHPs show blue-cyan fluorescence in MeOH with the quantum yield Φ = 0.10–0.22 relative to quinine sulfate Φ = 0.58 and 1,4-DHPs show blue-violet fluorescence with Φ = 0.09–0.81.",
publisher = "Royal Society of Chemistry",
journal = "Organic & Biomolecular Chemistry",
title = "Supplementary material for: Aleksić, J., Stojanović, M., Bošković, J.,& Baranac-Stojanović, M.. (2023). Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry
Royal Society of Chemistry., 21(6), 1187-1205.
https://doi.org/10.1039/D2OB02119F",
volume = "21",
number = "6",
url = "https://hdl.handle.net/21.15107/rcub_cherry_5846"
}

Aleksić, J., Stojanović, M., Bošković, J.,& Baranac-Stojanović, M..Supplementary material for: Aleksić, J., Stojanović, M., Bošković, J.,& Baranac-Stojanović, M.. (2023). Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry
Royal Society of Chemistry., 21(6), 1187-1205.
https://doi.org/10.1039/D2OB02119F. in Organic & Biomolecular Chemistry
Royal Society of Chemistry., 21(6).
https://hdl.handle.net/21.15107/rcub_cherry_5846

Aleksić J, Stojanović M, Bošković J, Baranac-Stojanović M. Supplementary material for: Aleksić, J., Stojanović, M., Bošković, J.,& Baranac-Stojanović, M.. (2023). Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry
Royal Society of Chemistry., 21(6), 1187-1205.
https://doi.org/10.1039/D2OB02119F. in Organic & Biomolecular Chemistry.21(6).
https://hdl.handle.net/21.15107/rcub_cherry_5846 .

Aleksić, Jovana, Stojanović, Milovan, Bošković, Jakša, Baranac-Stojanović, Marija, "Supplementary material for: Aleksić, J., Stojanović, M., Bošković, J.,& Baranac-Stojanović, M.. (2023). Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry
Royal Society of Chemistry., 21(6), 1187-1205.
https://doi.org/10.1039/D2OB02119F" in Organic & Biomolecular Chemistry, 21, no. 6,
https://hdl.handle.net/21.15107/rcub_cherry_5846 .

TY  - JOUR
AU  - Baranac-Stojanović, Marija
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
PY  - 2024
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/6417
AB  - Computational investigationattheBHandHLYP/6-311+G(d,p) leveloftheoryofthegas-phasetautomerismof2-and4-pyridonesconfirmedtheslightprevalenceof lactiminthecaseof theformer,but its dominance inthecaseof the latter, asshownpreviously. Examinationof aromaticitybyusingHOMA, EDDB, NBOdel, NICSandAICD led to theconclusion that tautomerizationof 4-pyridone results in greateraromaticitygain. ItisalsodrivenbythePaulirepulsionrelief,whichwasrevealedbythetautomerizationenergydecompositionanalysis.Bycontrast, inthecaseof2-pyridone, lactimisfavouredbyorbital andelectrostatic interactions anddisfavouredby thePauli repulsion. Aromaticitygain in this case is smaller.Thepositionofthetautomericequilibriumcanbemodulatedbysubstituent inductiveeffects(Cl andF), inductiveandresonanceeffects (NH2andNO2),hydrogenbonding(NO2),andmediumpolarity, theincreaseofwhichincreaseslactampopulation.
T2  - Organic & Biomolecular Chemistry
T1  - Theoretical investigation of tautomerism of 2- and 4-pyridones: origin, substituent and solvent effects
VL  - 22
IS  - 1
SP  - 144
EP  - 158
DO  - 10.1039/D3OB01588B
ER  - 

@article{
author = "Baranac-Stojanović, Marija and Aleksić, Jovana and Stojanović, Milovan",
year = "2024",
abstract = "Computational investigationattheBHandHLYP/6-311+G(d,p) leveloftheoryofthegas-phasetautomerismof2-and4-pyridonesconfirmedtheslightprevalenceof lactiminthecaseof theformer,but its dominance inthecaseof the latter, asshownpreviously. Examinationof aromaticitybyusingHOMA, EDDB, NBOdel, NICSandAICD led to theconclusion that tautomerizationof 4-pyridone results in greateraromaticitygain. ItisalsodrivenbythePaulirepulsionrelief,whichwasrevealedbythetautomerizationenergydecompositionanalysis.Bycontrast, inthecaseof2-pyridone, lactimisfavouredbyorbital andelectrostatic interactions anddisfavouredby thePauli repulsion. Aromaticitygain in this case is smaller.Thepositionofthetautomericequilibriumcanbemodulatedbysubstituent inductiveeffects(Cl andF), inductiveandresonanceeffects (NH2andNO2),hydrogenbonding(NO2),andmediumpolarity, theincreaseofwhichincreaseslactampopulation.",
journal = "Organic & Biomolecular Chemistry",
title = "Theoretical investigation of tautomerism of 2- and 4-pyridones: origin, substituent and solvent effects",
volume = "22",
number = "1",
pages = "144-158",
doi = "10.1039/D3OB01588B"
}

Baranac-Stojanović, M., Aleksić, J.,& Stojanović, M.. (2024). Theoretical investigation of tautomerism of 2- and 4-pyridones: origin, substituent and solvent effects. in Organic & Biomolecular Chemistry, 22(1), 144-158.
https://doi.org/10.1039/D3OB01588B

Baranac-Stojanović M, Aleksić J, Stojanović M. Theoretical investigation of tautomerism of 2- and 4-pyridones: origin, substituent and solvent effects. in Organic & Biomolecular Chemistry. 2024;22(1):144-158.
doi:10.1039/D3OB01588B .

Baranac-Stojanović, Marija, Aleksić, Jovana, Stojanović, Milovan, "Theoretical investigation of tautomerism of 2- and 4-pyridones: origin, substituent and solvent effects" in Organic & Biomolecular Chemistry, 22, no. 1 (2024):144-158,
https://doi.org/10.1039/D3OB01588B . .

TY  - JOUR
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
AU  - Baranac-Stojanović, Marija
PY  - 2023
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/5626
AB  - Aromaticity rules in the ground singlet state and the first excited triplet state are exactly opposite, as shown by Baird. Thus, (4n + 2)π electron annulenes are antiaromatic and 4nπ annulenes are aromatic in their triplet state. In this work, we employ quantum-mechanical calculations at the density functional theory (DFT) level to examine (anti)aromaticity of singlet and triplet corannulene dianion and dication in their bowl-shaped ground-state structure and planar transition-state structure. We find that singlet dianion contains aromatic hub and antiaromatic rim, whereas singlet dication is an antiaromatic system. This agrees with previous calculations of current density induced by perpendicular magnetic field. For triplet dianion, we find that it can be described as having aromatic rim and nonaromatic hub. Triplet dication was found to be nonaromatic, though in planar transition-state structure, locally and semiglobally antiaromatic naphthalene subunit and aromatic central ring can be discerned. © 2022 John Wiley & Sons Ltd.
PB  - Wiley
T2  - Journal of Physical Organic Chemistry
T1  - Aromaticity study of singlet- and triplet-state corannulene dianion and dication
VL  - 36
IS  - 1
SP  - e4434
DO  - 10.1002/poc.4434
ER  - 

@article{
author = "Aleksić, Jovana and Stojanović, Milovan and Baranac-Stojanović, Marija",
year = "2023",
abstract = "Aromaticity rules in the ground singlet state and the first excited triplet state are exactly opposite, as shown by Baird. Thus, (4n + 2)π electron annulenes are antiaromatic and 4nπ annulenes are aromatic in their triplet state. In this work, we employ quantum-mechanical calculations at the density functional theory (DFT) level to examine (anti)aromaticity of singlet and triplet corannulene dianion and dication in their bowl-shaped ground-state structure and planar transition-state structure. We find that singlet dianion contains aromatic hub and antiaromatic rim, whereas singlet dication is an antiaromatic system. This agrees with previous calculations of current density induced by perpendicular magnetic field. For triplet dianion, we find that it can be described as having aromatic rim and nonaromatic hub. Triplet dication was found to be nonaromatic, though in planar transition-state structure, locally and semiglobally antiaromatic naphthalene subunit and aromatic central ring can be discerned. © 2022 John Wiley & Sons Ltd.",
publisher = "Wiley",
journal = "Journal of Physical Organic Chemistry",
title = "Aromaticity study of singlet- and triplet-state corannulene dianion and dication",
volume = "36",
number = "1",
pages = "e4434",
doi = "10.1002/poc.4434"
}

Aleksić, J., Stojanović, M.,& Baranac-Stojanović, M.. (2023). Aromaticity study of singlet- and triplet-state corannulene dianion and dication. in Journal of Physical Organic Chemistry
Wiley., 36(1), e4434.
https://doi.org/10.1002/poc.4434

Aleksić J, Stojanović M, Baranac-Stojanović M. Aromaticity study of singlet- and triplet-state corannulene dianion and dication. in Journal of Physical Organic Chemistry. 2023;36(1):e4434.
doi:10.1002/poc.4434 .

Aleksić, Jovana, Stojanović, Milovan, Baranac-Stojanović, Marija, "Aromaticity study of singlet- and triplet-state corannulene dianion and dication" in Journal of Physical Organic Chemistry, 36, no. 1 (2023):e4434,
https://doi.org/10.1002/poc.4434 . .

TY  - JOUR
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
AU  - Bošković, Jakša
AU  - Baranac-Stojanović, Marija
PY  - 2023
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/5820
AB  - We present the green, highly atom-economical, solid-state silica gel-catalyzed synthesis of polysubstituted 1,4- and 1,2-dihydropyridines (DHPs) from commercially available materials, amines and ethyl propiolate. The DHP skeleton was assembled by heating the reactants and silica gel in a closed vessel. Aliphatic amines provided 1,4-isomers as the main or only DHP products, but the reactions of aromatic amines yielded a mixture of 1,4- and 1,2-isomers. To the best of our knowledge, this is the first example of the formation of a 1,2-DHP structure by the reaction of an amine with propiolic ester. Addition of 1 mass percent of H2SO4 to silica gel shifted the product distribution to 1,4-DHP as the main or the only isomer obtained. Experimental and theoretical analyses led to the identification of two key intermediates en route to DHPs and the explanation of the observed regioisomeric ratios. 1,2-DHPs show blue-cyan fluorescence in MeOH with the quantum yield Φ = 0.10–0.22 relative to quinine sulfate Φ = 0.58 and 1,4-DHPs show blue-violet fluorescence with Φ = 0.09–0.81.
PB  - Royal Society of Chemistry
T2  - Organic & Biomolecular Chemistry
T1  - Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines
VL  - 21
IS  - 6
SP  - 1187
EP  - 1205
DO  - 10.1039/D2OB02119F
ER  - 

@article{
author = "Aleksić, Jovana and Stojanović, Milovan and Bošković, Jakša and Baranac-Stojanović, Marija",
year = "2023",
abstract = "We present the green, highly atom-economical, solid-state silica gel-catalyzed synthesis of polysubstituted 1,4- and 1,2-dihydropyridines (DHPs) from commercially available materials, amines and ethyl propiolate. The DHP skeleton was assembled by heating the reactants and silica gel in a closed vessel. Aliphatic amines provided 1,4-isomers as the main or only DHP products, but the reactions of aromatic amines yielded a mixture of 1,4- and 1,2-isomers. To the best of our knowledge, this is the first example of the formation of a 1,2-DHP structure by the reaction of an amine with propiolic ester. Addition of 1 mass percent of H2SO4 to silica gel shifted the product distribution to 1,4-DHP as the main or the only isomer obtained. Experimental and theoretical analyses led to the identification of two key intermediates en route to DHPs and the explanation of the observed regioisomeric ratios. 1,2-DHPs show blue-cyan fluorescence in MeOH with the quantum yield Φ = 0.10–0.22 relative to quinine sulfate Φ = 0.58 and 1,4-DHPs show blue-violet fluorescence with Φ = 0.09–0.81.",
publisher = "Royal Society of Chemistry",
journal = "Organic & Biomolecular Chemistry",
title = "Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines",
volume = "21",
number = "6",
pages = "1187-1205",
doi = "10.1039/D2OB02119F"
}

Aleksić, J., Stojanović, M., Bošković, J.,& Baranac-Stojanović, M.. (2023). Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry
Royal Society of Chemistry., 21(6), 1187-1205.
https://doi.org/10.1039/D2OB02119F

Aleksić J, Stojanović M, Bošković J, Baranac-Stojanović M. Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry. 2023;21(6):1187-1205.
doi:10.1039/D2OB02119F .

Aleksić, Jovana, Stojanović, Milovan, Bošković, Jakša, Baranac-Stojanović, Marija, "Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines" in Organic & Biomolecular Chemistry, 21, no. 6 (2023):1187-1205,
https://doi.org/10.1039/D2OB02119F . .

TY  - JOUR
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
AU  - Bošković, Jakša
AU  - Baranac-Stojanović, Marija
PY  - 2023
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/6106
AB  - We present the green, highly atom-economical, solid-state silica gel-catalyzed synthesis of polysubstituted 1,4- and 1,2-dihydropyridines (DHPs) from commercially available materials, amines and ethyl propiolate. The DHP skeleton was assembled by heating the reactants and silica gel in a closed vessel. Aliphatic amines provided 1,4-isomers as the main or only DHP products, but the reactions of aromatic amines yielded a mixture of 1,4- and 1,2-isomers. To the best of our knowledge, this is the first example of the formation of a 1,2-DHP structure by the reaction of an amine with propiolic ester. Addition of 1 mass percent of H2SO4 to silica gel shifted the product distribution to 1,4-DHP as the main or the only isomer obtained. Experimental and theoretical analyses led to the identification of two key intermediates en route to DHPs and the explanation of the observed regioisomeric ratios. 1,2-DHPs show blue-cyan fluorescence in MeOH with the quantum yield Φ = 0.10–0.22 relative to quinine sulfate Φ = 0.58 and 1,4-DHPs show blue-violet fluorescence with Φ = 0.09–0.81.
T2  - Organic & Biomolecular Chemistry
T1  - Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines
VL  - 21
IS  - 6
SP  - 1187
EP  - 1205
DO  - 10.1039/D2OB02119F
ER  - 

@article{
author = "Aleksić, Jovana and Stojanović, Milovan and Bošković, Jakša and Baranac-Stojanović, Marija",
year = "2023",
abstract = "We present the green, highly atom-economical, solid-state silica gel-catalyzed synthesis of polysubstituted 1,4- and 1,2-dihydropyridines (DHPs) from commercially available materials, amines and ethyl propiolate. The DHP skeleton was assembled by heating the reactants and silica gel in a closed vessel. Aliphatic amines provided 1,4-isomers as the main or only DHP products, but the reactions of aromatic amines yielded a mixture of 1,4- and 1,2-isomers. To the best of our knowledge, this is the first example of the formation of a 1,2-DHP structure by the reaction of an amine with propiolic ester. Addition of 1 mass percent of H2SO4 to silica gel shifted the product distribution to 1,4-DHP as the main or the only isomer obtained. Experimental and theoretical analyses led to the identification of two key intermediates en route to DHPs and the explanation of the observed regioisomeric ratios. 1,2-DHPs show blue-cyan fluorescence in MeOH with the quantum yield Φ = 0.10–0.22 relative to quinine sulfate Φ = 0.58 and 1,4-DHPs show blue-violet fluorescence with Φ = 0.09–0.81.",
journal = "Organic & Biomolecular Chemistry",
title = "Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines",
volume = "21",
number = "6",
pages = "1187-1205",
doi = "10.1039/D2OB02119F"
}

Aleksić, J., Stojanović, M., Bošković, J.,& Baranac-Stojanović, M.. (2023). Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry, 21(6), 1187-1205.
https://doi.org/10.1039/D2OB02119F

Aleksić J, Stojanović M, Bošković J, Baranac-Stojanović M. Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines. in Organic & Biomolecular Chemistry. 2023;21(6):1187-1205.
doi:10.1039/D2OB02119F .

Aleksić, Jovana, Stojanović, Milovan, Bošković, Jakša, Baranac-Stojanović, Marija, "Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines" in Organic & Biomolecular Chemistry, 21, no. 6 (2023):1187-1205,
https://doi.org/10.1039/D2OB02119F . .

TY  - JOUR
AU  - Baranac-Stojanović, Marija
AU  - Stojanović, Milovan
AU  - Aleksić, Jovana
PY  - 2022
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/4889
AB  - By employing density functional theory (DFT) calculations we show that mono- and disilicon substitution in polycyclic aromatic hydrocarbons, having two to four benzene units, quenches their triplet state antiaromaticity by creating Hückel aromatic (poly)benzenoid subunit(s) and weakly antiaromatic, or almost nonaromatic silacycle. Therefore, such systems are predicted to be globally aromatic in both the ground state and the first excited triplet state. Putting the silicon atom(s) into various positions of a hydrocarbon provides an opportunity to tune the singlet-triplet energy gaps. They depend on the global aromaticity degree which, in turn, depends on the type of aromatic carbocyclic subunit(s) and the extent of their aromaticity. On the basis of the set of studied compounds, some preliminary rules on how to regulate the extent of global, semiglobal and local aromaticity are proposed. The results of this work extend the importance of Hückel aromaticity concept to excited triplet states which are usually characterized by the Baird type of (anti)aromaticity.
PB  - Wiley
T2  - Chemistry. An Asian Journal
T1  - Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution
VL  - 17
IS  - 4
SP  - e202101261
DO  - 10.1002/asia.202101261
ER  - 

@article{
author = "Baranac-Stojanović, Marija and Stojanović, Milovan and Aleksić, Jovana",
year = "2022",
abstract = "By employing density functional theory (DFT) calculations we show that mono- and disilicon substitution in polycyclic aromatic hydrocarbons, having two to four benzene units, quenches their triplet state antiaromaticity by creating Hückel aromatic (poly)benzenoid subunit(s) and weakly antiaromatic, or almost nonaromatic silacycle. Therefore, such systems are predicted to be globally aromatic in both the ground state and the first excited triplet state. Putting the silicon atom(s) into various positions of a hydrocarbon provides an opportunity to tune the singlet-triplet energy gaps. They depend on the global aromaticity degree which, in turn, depends on the type of aromatic carbocyclic subunit(s) and the extent of their aromaticity. On the basis of the set of studied compounds, some preliminary rules on how to regulate the extent of global, semiglobal and local aromaticity are proposed. The results of this work extend the importance of Hückel aromaticity concept to excited triplet states which are usually characterized by the Baird type of (anti)aromaticity.",
publisher = "Wiley",
journal = "Chemistry. An Asian Journal",
title = "Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution",
volume = "17",
number = "4",
pages = "e202101261",
doi = "10.1002/asia.202101261"
}

Baranac-Stojanović, M., Stojanović, M.,& Aleksić, J.. (2022). Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. in Chemistry. An Asian Journal
Wiley., 17(4), e202101261.
https://doi.org/10.1002/asia.202101261

Baranac-Stojanović M, Stojanović M, Aleksić J. Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. in Chemistry. An Asian Journal. 2022;17(4):e202101261.
doi:10.1002/asia.202101261 .

Baranac-Stojanović, Marija, Stojanović, Milovan, Aleksić, Jovana, "Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution" in Chemistry. An Asian Journal, 17, no. 4 (2022):e202101261,
https://doi.org/10.1002/asia.202101261 . .

TY  - DATA
AU  - Baranac-Stojanović, Marija
AU  - Stojanović, Milovan
AU  - Aleksić, Jovana
PY  - 2022
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/4890
PB  - Wiley
T2  - Chemistry. An Asian Journal
T1  - Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Revival of Hückel Aromatic (Poly)Benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. Chemistry – An Asian Journal 2022, 17 (4), e202101261. https://doi.org/10.1002/asia.202101261.
UR  - https://hdl.handle.net/21.15107/rcub_cherry_4890
ER  - 

@misc{
author = "Baranac-Stojanović, Marija and Stojanović, Milovan and Aleksić, Jovana",
year = "2022",
publisher = "Wiley",
journal = "Chemistry. An Asian Journal",
title = "Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Revival of Hückel Aromatic (Poly)Benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. Chemistry – An Asian Journal 2022, 17 (4), e202101261. https://doi.org/10.1002/asia.202101261.",
url = "https://hdl.handle.net/21.15107/rcub_cherry_4890"
}

Baranac-Stojanović, M., Stojanović, M.,& Aleksić, J.. (2022). Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Revival of Hückel Aromatic (Poly)Benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. Chemistry – An Asian Journal 2022, 17 (4), e202101261. https://doi.org/10.1002/asia.202101261.. in Chemistry. An Asian Journal
Wiley..
https://hdl.handle.net/21.15107/rcub_cherry_4890

Baranac-Stojanović M, Stojanović M, Aleksić J. Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Revival of Hückel Aromatic (Poly)Benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. Chemistry – An Asian Journal 2022, 17 (4), e202101261. https://doi.org/10.1002/asia.202101261.. in Chemistry. An Asian Journal. 2022;.
https://hdl.handle.net/21.15107/rcub_cherry_4890 .

Baranac-Stojanović, Marija, Stojanović, Milovan, Aleksić, Jovana, "Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Revival of Hückel Aromatic (Poly)Benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution. Chemistry – An Asian Journal 2022, 17 (4), e202101261. https://doi.org/10.1002/asia.202101261." in Chemistry. An Asian Journal (2022),
https://hdl.handle.net/21.15107/rcub_cherry_4890 .

TY  - JOUR
AU  - Baranac-Stojanović, Marija
AU  - Stojanović, Milovan
AU  - Aleksić, Jovana
PY  - 2021
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/4355
AB  - Aromaticity–antiaromaticity switch upon singlet–triplet transition of some biologically and synthetically important monoheterocycles (heteroatom = N, O, Si, P, and S) derived from benzene, naphthalene and anthracene was studied by employing energetic, magnetic and structural aromaticity criteria, at the density functional theory (DFT) level. The relationship between spin density distribution, (anti)aromaticity and singlet–triplet energy gaps, in the studied molecules, was found. In general, spin delocalization results in antiaromaticity, spin density localization to one ring in bi- and tricycles localizes antiaromaticity and spin localization on a heteroatom reduces global and local antiaromaticity. The latter reaches nonaromaticity in the case of silicon atoms which have larger orbitals and show more tendency to accept unpaired electrons. Spin density localization in bi- and tricycles allows benzene subunit(s) to develop local aromaticity, which, when combined with nonaromatic silacycle and weak global antiaromaticity, results in overall triplet state weak aromaticity. The singlet–triplet energy gaps decrease with a decrease in the triplet state antiaromaticity and are the lowest for silicon-containing compounds.
PB  - Royal Society of Chemistry
T2  - New Journal of Chemistry
T1  - Triplet state (anti)aromaticity of some monoheterocyclic analogues of benzene, naphthalene and anthracene
VL  - 45
IS  - 11
SP  - 5060
EP  - 5074
DO  - 10.1039/D1NJ00207D
ER  - 

@article{
author = "Baranac-Stojanović, Marija and Stojanović, Milovan and Aleksić, Jovana",
year = "2021",
abstract = "Aromaticity–antiaromaticity switch upon singlet–triplet transition of some biologically and synthetically important monoheterocycles (heteroatom = N, O, Si, P, and S) derived from benzene, naphthalene and anthracene was studied by employing energetic, magnetic and structural aromaticity criteria, at the density functional theory (DFT) level. The relationship between spin density distribution, (anti)aromaticity and singlet–triplet energy gaps, in the studied molecules, was found. In general, spin delocalization results in antiaromaticity, spin density localization to one ring in bi- and tricycles localizes antiaromaticity and spin localization on a heteroatom reduces global and local antiaromaticity. The latter reaches nonaromaticity in the case of silicon atoms which have larger orbitals and show more tendency to accept unpaired electrons. Spin density localization in bi- and tricycles allows benzene subunit(s) to develop local aromaticity, which, when combined with nonaromatic silacycle and weak global antiaromaticity, results in overall triplet state weak aromaticity. The singlet–triplet energy gaps decrease with a decrease in the triplet state antiaromaticity and are the lowest for silicon-containing compounds.",
publisher = "Royal Society of Chemistry",
journal = "New Journal of Chemistry",
title = "Triplet state (anti)aromaticity of some monoheterocyclic analogues of benzene, naphthalene and anthracene",
volume = "45",
number = "11",
pages = "5060-5074",
doi = "10.1039/D1NJ00207D"
}

Baranac-Stojanović, M., Stojanović, M.,& Aleksić, J.. (2021). Triplet state (anti)aromaticity of some monoheterocyclic analogues of benzene, naphthalene and anthracene. in New Journal of Chemistry
Royal Society of Chemistry., 45(11), 5060-5074.
https://doi.org/10.1039/D1NJ00207D

Baranac-Stojanović M, Stojanović M, Aleksić J. Triplet state (anti)aromaticity of some monoheterocyclic analogues of benzene, naphthalene and anthracene. in New Journal of Chemistry. 2021;45(11):5060-5074.
doi:10.1039/D1NJ00207D .

Baranac-Stojanović, Marija, Stojanović, Milovan, Aleksić, Jovana, "Triplet state (anti)aromaticity of some monoheterocyclic analogues of benzene, naphthalene and anthracene" in New Journal of Chemistry, 45, no. 11 (2021):5060-5074,
https://doi.org/10.1039/D1NJ00207D . .

TY  - DATA
AU  - Baranac-Stojanović, Marija
AU  - Stojanović, Milovan
AU  - Aleksić, Jovana
PY  - 2021
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/4356
PB  - Royal Society of Chemistry
T2  - New Journal of Chemistry
T1  - Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Triplet State (Anti)Aromaticity of Some Monoheterocyclic Analogues of Benzene, Naphthalene and Anthracene. New J. Chem. 2021, 45 (11), 5060–5074. https://doi.org/10.1039/D1NJ00207D.
UR  - https://hdl.handle.net/21.15107/rcub_cherry_4356
ER  - 

@misc{
author = "Baranac-Stojanović, Marija and Stojanović, Milovan and Aleksić, Jovana",
year = "2021",
publisher = "Royal Society of Chemistry",
journal = "New Journal of Chemistry",
title = "Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Triplet State (Anti)Aromaticity of Some Monoheterocyclic Analogues of Benzene, Naphthalene and Anthracene. New J. Chem. 2021, 45 (11), 5060–5074. https://doi.org/10.1039/D1NJ00207D.",
url = "https://hdl.handle.net/21.15107/rcub_cherry_4356"
}

Baranac-Stojanović, M., Stojanović, M.,& Aleksić, J.. (2021). Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Triplet State (Anti)Aromaticity of Some Monoheterocyclic Analogues of Benzene, Naphthalene and Anthracene. New J. Chem. 2021, 45 (11), 5060–5074. https://doi.org/10.1039/D1NJ00207D.. in New Journal of Chemistry
Royal Society of Chemistry..
https://hdl.handle.net/21.15107/rcub_cherry_4356

Baranac-Stojanović M, Stojanović M, Aleksić J. Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Triplet State (Anti)Aromaticity of Some Monoheterocyclic Analogues of Benzene, Naphthalene and Anthracene. New J. Chem. 2021, 45 (11), 5060–5074. https://doi.org/10.1039/D1NJ00207D.. in New Journal of Chemistry. 2021;.
https://hdl.handle.net/21.15107/rcub_cherry_4356 .

Baranac-Stojanović, Marija, Stojanović, Milovan, Aleksić, Jovana, "Supplementary data for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Triplet State (Anti)Aromaticity of Some Monoheterocyclic Analogues of Benzene, Naphthalene and Anthracene. New J. Chem. 2021, 45 (11), 5060–5074. https://doi.org/10.1039/D1NJ00207D." in New Journal of Chemistry (2021),
https://hdl.handle.net/21.15107/rcub_cherry_4356 .

TY  - JOUR
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
AU  - Baranac-Stojanović, Marija
PY  - 2018
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/2188
AB  - We present an efficient, simple, metal- and solvent-free silica-gel-promoted synthesis of functionalized conjugated dienes by sequential aza-Michael/Michael reactions by starting from commercially available primary amines and propiolic esters. The scope and usefulness of the method is demonstrated for 31examples, including a range of propiolic esters, aliphatic amines, and differently substituted aromatic amines. For aliphatic amines, the products were obtained within 0.5 to 4h in 52 to 85% yield, compared with 3.5 to 22h under classical solution-phase synthesis, which proceeds with similar or lower yields. The method was found to be particularly useful for weakly nucleophilic aromatic amines, which provided products in 21 to 73% yield over 2.5 to 9.5h compared with yields of 0 to 49% over 1 to 6d under standard solution-phase conditions, and for more hydrophobic esters that gave products in yields of 47 to 79% over 1 to 3h compared with 0 to 45% over 4 to 114h in solvent.
PB  - Wiley-V C H Verlag Gmbh, Weinheim
T2  - Chemistry. An Asian Journal
T1  - Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes
VL  - 13
IS  - 14
SP  - 1811
EP  - 1835
DO  - 10.1002/asia.201800645
ER  - 

@article{
author = "Aleksić, Jovana and Stojanović, Milovan and Baranac-Stojanović, Marija",
year = "2018",
abstract = "We present an efficient, simple, metal- and solvent-free silica-gel-promoted synthesis of functionalized conjugated dienes by sequential aza-Michael/Michael reactions by starting from commercially available primary amines and propiolic esters. The scope and usefulness of the method is demonstrated for 31examples, including a range of propiolic esters, aliphatic amines, and differently substituted aromatic amines. For aliphatic amines, the products were obtained within 0.5 to 4h in 52 to 85% yield, compared with 3.5 to 22h under classical solution-phase synthesis, which proceeds with similar or lower yields. The method was found to be particularly useful for weakly nucleophilic aromatic amines, which provided products in 21 to 73% yield over 2.5 to 9.5h compared with yields of 0 to 49% over 1 to 6d under standard solution-phase conditions, and for more hydrophobic esters that gave products in yields of 47 to 79% over 1 to 3h compared with 0 to 45% over 4 to 114h in solvent.",
publisher = "Wiley-V C H Verlag Gmbh, Weinheim",
journal = "Chemistry. An Asian Journal",
title = "Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes",
volume = "13",
number = "14",
pages = "1811-1835",
doi = "10.1002/asia.201800645"
}

Aleksić, J., Stojanović, M.,& Baranac-Stojanović, M.. (2018). Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes. in Chemistry. An Asian Journal
Wiley-V C H Verlag Gmbh, Weinheim., 13(14), 1811-1835.
https://doi.org/10.1002/asia.201800645

Aleksić J, Stojanović M, Baranac-Stojanović M. Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes. in Chemistry. An Asian Journal. 2018;13(14):1811-1835.
doi:10.1002/asia.201800645 .

Aleksić, Jovana, Stojanović, Milovan, Baranac-Stojanović, Marija, "Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes" in Chemistry. An Asian Journal, 13, no. 14 (2018):1811-1835,
https://doi.org/10.1002/asia.201800645 . .

TY  - JOUR
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
AU  - Baranac-Stojanović, Marija
PY  - 2018
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/2947
AB  - We present an efficient, simple, metal- and solvent-free silica-gel-promoted synthesis of functionalized conjugated dienes by sequential aza-Michael/Michael reactions by starting from commercially available primary amines and propiolic esters. The scope and usefulness of the method is demonstrated for 31examples, including a range of propiolic esters, aliphatic amines, and differently substituted aromatic amines. For aliphatic amines, the products were obtained within 0.5 to 4h in 52 to 85% yield, compared with 3.5 to 22h under classical solution-phase synthesis, which proceeds with similar or lower yields. The method was found to be particularly useful for weakly nucleophilic aromatic amines, which provided products in 21 to 73% yield over 2.5 to 9.5h compared with yields of 0 to 49% over 1 to 6d under standard solution-phase conditions, and for more hydrophobic esters that gave products in yields of 47 to 79% over 1 to 3h compared with 0 to 45% over 4 to 114h in solvent.
PB  - Wiley-V C H Verlag Gmbh, Weinheim
T2  - Chemistry. An Asian Journal
T1  - Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes
VL  - 13
IS  - 14
SP  - 1811
EP  - 1835
DO  - 10.1002/asia.201800645
ER  - 

@article{
author = "Aleksić, Jovana and Stojanović, Milovan and Baranac-Stojanović, Marija",
year = "2018",
abstract = "We present an efficient, simple, metal- and solvent-free silica-gel-promoted synthesis of functionalized conjugated dienes by sequential aza-Michael/Michael reactions by starting from commercially available primary amines and propiolic esters. The scope and usefulness of the method is demonstrated for 31examples, including a range of propiolic esters, aliphatic amines, and differently substituted aromatic amines. For aliphatic amines, the products were obtained within 0.5 to 4h in 52 to 85% yield, compared with 3.5 to 22h under classical solution-phase synthesis, which proceeds with similar or lower yields. The method was found to be particularly useful for weakly nucleophilic aromatic amines, which provided products in 21 to 73% yield over 2.5 to 9.5h compared with yields of 0 to 49% over 1 to 6d under standard solution-phase conditions, and for more hydrophobic esters that gave products in yields of 47 to 79% over 1 to 3h compared with 0 to 45% over 4 to 114h in solvent.",
publisher = "Wiley-V C H Verlag Gmbh, Weinheim",
journal = "Chemistry. An Asian Journal",
title = "Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes",
volume = "13",
number = "14",
pages = "1811-1835",
doi = "10.1002/asia.201800645"
}

Aleksić, J., Stojanović, M.,& Baranac-Stojanović, M.. (2018). Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes. in Chemistry. An Asian Journal
Wiley-V C H Verlag Gmbh, Weinheim., 13(14), 1811-1835.
https://doi.org/10.1002/asia.201800645

Aleksić J, Stojanović M, Baranac-Stojanović M. Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes. in Chemistry. An Asian Journal. 2018;13(14):1811-1835.
doi:10.1002/asia.201800645 .

Aleksić, Jovana, Stojanović, Milovan, Baranac-Stojanović, Marija, "Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes" in Chemistry. An Asian Journal, 13, no. 14 (2018):1811-1835,
https://doi.org/10.1002/asia.201800645 . .

TY  - JOUR
AU  - Baranac-Stojanović, Marija
AU  - Stojanović, Milovan
AU  - Aleksić, Jovana
PY  - 2017
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/2464
AB  - The strength of the azido gauche effect in 1,2-diazidoethane, N-(2-azidoethyl)ethanamide, (protonated) 2-azidoethanamine and (protonated) 2-azidoethanol and its origin were theoretically studied at the MP2/6-311++G(d,p) level of theory. The results show that the azido gauche effect in the amine and alcohol can exert a control over the molecular conformation to a similar extent as the fluorine gauche effect, but to a greater extent in the charged species, amide and vicinal diazido fragment. A quantitative partitioning of isomerization energy into contributions from electrostatic, orbital, dispersion and Pauli interactions and energy consumed in structural changes revealed that electrostatic forces play an important role in the stabilization of the gauche isomer in the two charged species and alcohol. Electrostatic and dispersion interactions are the main contributors to the gauche effect in the amide, whereas dispersion and orbital interactions can be considered to be the two most important stabilizing factors of the gauche form in the vicinal diazido fragment. The interplay of all three stabilizing interactions determines the gauche preference in the amine. Stereoelectronic effects, which are involved in orbital interactions, contribute to the gauche effect in all the molecules except the 2-azidoethylammonium ion and protonated 2-azidoethanol. Hydrogen-bonding interactions were found only in the protonated alcohol.
PB  - Royal Soc Chemistry, Cambridge
T2  - New Journal of Chemistry
T1  - Theoretical study of azido gauche effect and its origin
VL  - 41
IS  - 11
SP  - 4644
EP  - 4661
DO  - 10.1039/c7nj00369b
ER  - 

@article{
author = "Baranac-Stojanović, Marija and Stojanović, Milovan and Aleksić, Jovana",
year = "2017",
abstract = "The strength of the azido gauche effect in 1,2-diazidoethane, N-(2-azidoethyl)ethanamide, (protonated) 2-azidoethanamine and (protonated) 2-azidoethanol and its origin were theoretically studied at the MP2/6-311++G(d,p) level of theory. The results show that the azido gauche effect in the amine and alcohol can exert a control over the molecular conformation to a similar extent as the fluorine gauche effect, but to a greater extent in the charged species, amide and vicinal diazido fragment. A quantitative partitioning of isomerization energy into contributions from electrostatic, orbital, dispersion and Pauli interactions and energy consumed in structural changes revealed that electrostatic forces play an important role in the stabilization of the gauche isomer in the two charged species and alcohol. Electrostatic and dispersion interactions are the main contributors to the gauche effect in the amide, whereas dispersion and orbital interactions can be considered to be the two most important stabilizing factors of the gauche form in the vicinal diazido fragment. The interplay of all three stabilizing interactions determines the gauche preference in the amine. Stereoelectronic effects, which are involved in orbital interactions, contribute to the gauche effect in all the molecules except the 2-azidoethylammonium ion and protonated 2-azidoethanol. Hydrogen-bonding interactions were found only in the protonated alcohol.",
publisher = "Royal Soc Chemistry, Cambridge",
journal = "New Journal of Chemistry",
title = "Theoretical study of azido gauche effect and its origin",
volume = "41",
number = "11",
pages = "4644-4661",
doi = "10.1039/c7nj00369b"
}

Baranac-Stojanović, M., Stojanović, M.,& Aleksić, J.. (2017). Theoretical study of azido gauche effect and its origin. in New Journal of Chemistry
Royal Soc Chemistry, Cambridge., 41(11), 4644-4661.
https://doi.org/10.1039/c7nj00369b

Baranac-Stojanović M, Stojanović M, Aleksić J. Theoretical study of azido gauche effect and its origin. in New Journal of Chemistry. 2017;41(11):4644-4661.
doi:10.1039/c7nj00369b .

Baranac-Stojanović, Marija, Stojanović, Milovan, Aleksić, Jovana, "Theoretical study of azido gauche effect and its origin" in New Journal of Chemistry, 41, no. 11 (2017):4644-4661,
https://doi.org/10.1039/c7nj00369b . .

TY  - DATA
AU  - Baranac-Stojanović, Marija
AU  - Stojanović, Milovan
AU  - Aleksić, Jovana
PY  - 2017
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/3260
PB  - Royal Soc Chemistry, Cambridge
T2  - New Journal of Chemistry
T1  - Supplementary material for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Theoretical Study of Azido: Gauche Effect and Its Origin. New Journal of Chemistry 2017, 41 (11), 4644–4661. https://doi.org/10.1039/c7nj00369b
UR  - https://hdl.handle.net/21.15107/rcub_cherry_3260
ER  - 

@misc{
author = "Baranac-Stojanović, Marija and Stojanović, Milovan and Aleksić, Jovana",
year = "2017",
publisher = "Royal Soc Chemistry, Cambridge",
journal = "New Journal of Chemistry",
title = "Supplementary material for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Theoretical Study of Azido: Gauche Effect and Its Origin. New Journal of Chemistry 2017, 41 (11), 4644–4661. https://doi.org/10.1039/c7nj00369b",
url = "https://hdl.handle.net/21.15107/rcub_cherry_3260"
}

Baranac-Stojanović, M., Stojanović, M.,& Aleksić, J.. (2017). Supplementary material for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Theoretical Study of Azido: Gauche Effect and Its Origin. New Journal of Chemistry 2017, 41 (11), 4644–4661. https://doi.org/10.1039/c7nj00369b. in New Journal of Chemistry
Royal Soc Chemistry, Cambridge..
https://hdl.handle.net/21.15107/rcub_cherry_3260

Baranac-Stojanović M, Stojanović M, Aleksić J. Supplementary material for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Theoretical Study of Azido: Gauche Effect and Its Origin. New Journal of Chemistry 2017, 41 (11), 4644–4661. https://doi.org/10.1039/c7nj00369b. in New Journal of Chemistry. 2017;.
https://hdl.handle.net/21.15107/rcub_cherry_3260 .

Baranac-Stojanović, Marija, Stojanović, Milovan, Aleksić, Jovana, "Supplementary material for the article: Baranac-Stojanović, M.; Stojanović, M.; Aleksić, J. Theoretical Study of Azido: Gauche Effect and Its Origin. New Journal of Chemistry 2017, 41 (11), 4644–4661. https://doi.org/10.1039/c7nj00369b" in New Journal of Chemistry (2017),
https://hdl.handle.net/21.15107/rcub_cherry_3260 .

TY  - JOUR
AU  - Baranac-Stojanović, Marija
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
PY  - 2015
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/1669
AB  - 2-Haloethanol and 2-haloethylamine (halogen = F, Cl) prefer gauche conformation. This preference is significantly increased upon protonation. Commonly used explanations are based on intramolecular hydrogen bonding and hyperconjugation. 1,2-Difluoroethane prefers gauche conformation, too, while gaseous 1-chloro-2-fluoroethane is more stable as the anti conformer. The origin of these conformational preferences has been investigated by a quantitative partitioning of the gauche/anti energy difference into contributions from electrostatic, orbital, dispersion and Pauli interactions, and structural changes accompanying the rotation. The results show that, with two exceptions, the most important contributor to the gauche preference is electrostatic attraction, which is larger in gauche forms relative to the anti ones. Next come orbital interactions, while dispersion forces provide the smallest stabilizing energy. These energy components override destabilizing Pauli interactions and energetically costly structural changes. All gauche preferences also benefit from stereoelectronic effects, except in protonated 2-chloroethanol which, instead, shows a significant Cl lone pair - gt  O-H antibond mixing, associated with hydrogen bonding. The increase in the Pauli repulsion upon anti to gauche isomerization is more pronounced for fluorine than for chlorine derivatives. Thus, the smaller gauche effect in chloro-compounds and the anti preference in 1-chloro-2-fluoroethane have their origin in the decrease in electrostatic and orbital stabilizing interactions, a drop in the former being more pronounced.
PB  - Royal Soc Chemistry, Cambridge
T2  - RSC Advances
T1  - Energy decomposition analysis of gauche preference in 2-haloethanol, 2-haloethylamine (halogen = F, Cl), their protonated forms and anti preference in 1-chloro-2-fluoroethane
VL  - 5
IS  - 29
SP  - 22980
EP  - 22995
DO  - 10.1039/c5ra01164g
ER  - 

@article{
author = "Baranac-Stojanović, Marija and Aleksić, Jovana and Stojanović, Milovan",
year = "2015",
abstract = "2-Haloethanol and 2-haloethylamine (halogen = F, Cl) prefer gauche conformation. This preference is significantly increased upon protonation. Commonly used explanations are based on intramolecular hydrogen bonding and hyperconjugation. 1,2-Difluoroethane prefers gauche conformation, too, while gaseous 1-chloro-2-fluoroethane is more stable as the anti conformer. The origin of these conformational preferences has been investigated by a quantitative partitioning of the gauche/anti energy difference into contributions from electrostatic, orbital, dispersion and Pauli interactions, and structural changes accompanying the rotation. The results show that, with two exceptions, the most important contributor to the gauche preference is electrostatic attraction, which is larger in gauche forms relative to the anti ones. Next come orbital interactions, while dispersion forces provide the smallest stabilizing energy. These energy components override destabilizing Pauli interactions and energetically costly structural changes. All gauche preferences also benefit from stereoelectronic effects, except in protonated 2-chloroethanol which, instead, shows a significant Cl lone pair - gt  O-H antibond mixing, associated with hydrogen bonding. The increase in the Pauli repulsion upon anti to gauche isomerization is more pronounced for fluorine than for chlorine derivatives. Thus, the smaller gauche effect in chloro-compounds and the anti preference in 1-chloro-2-fluoroethane have their origin in the decrease in electrostatic and orbital stabilizing interactions, a drop in the former being more pronounced.",
publisher = "Royal Soc Chemistry, Cambridge",
journal = "RSC Advances",
title = "Energy decomposition analysis of gauche preference in 2-haloethanol, 2-haloethylamine (halogen = F, Cl), their protonated forms and anti preference in 1-chloro-2-fluoroethane",
volume = "5",
number = "29",
pages = "22980-22995",
doi = "10.1039/c5ra01164g"
}

Baranac-Stojanović, M., Aleksić, J.,& Stojanović, M.. (2015). Energy decomposition analysis of gauche preference in 2-haloethanol, 2-haloethylamine (halogen = F, Cl), their protonated forms and anti preference in 1-chloro-2-fluoroethane. in RSC Advances
Royal Soc Chemistry, Cambridge., 5(29), 22980-22995.
https://doi.org/10.1039/c5ra01164g

Baranac-Stojanović M, Aleksić J, Stojanović M. Energy decomposition analysis of gauche preference in 2-haloethanol, 2-haloethylamine (halogen = F, Cl), their protonated forms and anti preference in 1-chloro-2-fluoroethane. in RSC Advances. 2015;5(29):22980-22995.
doi:10.1039/c5ra01164g .

Baranac-Stojanović, Marija, Aleksić, Jovana, Stojanović, Milovan, "Energy decomposition analysis of gauche preference in 2-haloethanol, 2-haloethylamine (halogen = F, Cl), their protonated forms and anti preference in 1-chloro-2-fluoroethane" in RSC Advances, 5, no. 29 (2015):22980-22995,
https://doi.org/10.1039/c5ra01164g . .

TY  - JOUR
AU  - Stojanović, Milovan
AU  - Aleksić, Jovana
AU  - Baranac-Stojanović, Marija
PY  - 2015
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/1734
AB  - The origin of the rotational barriers in n-butane and gauche conformational energy, the prototypes of steric repulsion, has been re-examined by using energy decomposition analysis. The Pauli repulsion was found to be an important factor, but not the source of the barriers and gauche/anti energy difference. Rather, it should be considered as a driving force for structural changes accompanying the rotation. The repulsion (steric) energy partly transfers into the deformation energy of ethyl fragments and also affects a decrease in electrostatic, orbital and dispersion interactions by inducing the structural changes, particularly the central CC bond lengthening, while it becomes less destabilizing during the anti-butane rotation.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Tetrahedron
T1  - The effect of steric repulsion on the torsional potential of n-butane: a theoretical study
VL  - 71
IS  - 32
SP  - 5119
EP  - 5123
DO  - 10.1016/j.tet.2015.06.002
ER  - 

@article{
author = "Stojanović, Milovan and Aleksić, Jovana and Baranac-Stojanović, Marija",
year = "2015",
abstract = "The origin of the rotational barriers in n-butane and gauche conformational energy, the prototypes of steric repulsion, has been re-examined by using energy decomposition analysis. The Pauli repulsion was found to be an important factor, but not the source of the barriers and gauche/anti energy difference. Rather, it should be considered as a driving force for structural changes accompanying the rotation. The repulsion (steric) energy partly transfers into the deformation energy of ethyl fragments and also affects a decrease in electrostatic, orbital and dispersion interactions by inducing the structural changes, particularly the central CC bond lengthening, while it becomes less destabilizing during the anti-butane rotation.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Tetrahedron",
title = "The effect of steric repulsion on the torsional potential of n-butane: a theoretical study",
volume = "71",
number = "32",
pages = "5119-5123",
doi = "10.1016/j.tet.2015.06.002"
}

Stojanović, M., Aleksić, J.,& Baranac-Stojanović, M.. (2015). The effect of steric repulsion on the torsional potential of n-butane: a theoretical study. in Tetrahedron
Pergamon-Elsevier Science Ltd, Oxford., 71(32), 5119-5123.
https://doi.org/10.1016/j.tet.2015.06.002

Stojanović M, Aleksić J, Baranac-Stojanović M. The effect of steric repulsion on the torsional potential of n-butane: a theoretical study. in Tetrahedron. 2015;71(32):5119-5123.
doi:10.1016/j.tet.2015.06.002 .

Stojanović, Milovan, Aleksić, Jovana, Baranac-Stojanović, Marija, "The effect of steric repulsion on the torsional potential of n-butane: a theoretical study" in Tetrahedron, 71, no. 32 (2015):5119-5123,
https://doi.org/10.1016/j.tet.2015.06.002 . .

TY  - JOUR
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
AU  - Baranac-Stojanović, Marija
PY  - 2015
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/1981
AB  - The well-known gauche preference in FCCX systems, where X is an electronegative element from Period 2, is widely exploited in synthetic, medicinal, and material chemistry. It is rationalized on the basis of sigma(C-H)- gt sigma*(C-F) hyperconjugation and electrostatic interactions. The recent report (Thiehoff, C.; et al. Chem. Sci. 2015, 6, 3565) showed that the fluorine gauche effect can extend to Period 3 elements, such as sulfur. The aim of the present work is to disclose factors governing conformational behavior of FCCS containing systems. We examine conformational preferences in seven classes of compounds by ab initio and DFT calculations and rationalize the results by quantitatively decomposing the anti/gauche isomerization energy into contributions from electrostatic, orbital, dispersion, and Pauli interactions, and energy spent on structural changes. The results show that the fluorine/sulfur gauche effect is primarily electrostatic (63-75%), while all orbital interactions contribute 22-41% to stabilizing interactions. Stereoelectronic effects, involved in orbital interactions, also play a role in gauche conformer stabilization.
PB  - Amer Chemical Soc, Washington
T2  - Journal of Organic Chemistry
T1  - Origin of Fluorine/Sulfur Gauche Effect of beta-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion
VL  - 80
IS  - 20
SP  - 10197
EP  - 10207
DO  - 10.1021/acs.joc.5b01779
ER  - 

@article{
author = "Aleksić, Jovana and Stojanović, Milovan and Baranac-Stojanović, Marija",
year = "2015",
abstract = "The well-known gauche preference in FCCX systems, where X is an electronegative element from Period 2, is widely exploited in synthetic, medicinal, and material chemistry. It is rationalized on the basis of sigma(C-H)- gt sigma*(C-F) hyperconjugation and electrostatic interactions. The recent report (Thiehoff, C.; et al. Chem. Sci. 2015, 6, 3565) showed that the fluorine gauche effect can extend to Period 3 elements, such as sulfur. The aim of the present work is to disclose factors governing conformational behavior of FCCS containing systems. We examine conformational preferences in seven classes of compounds by ab initio and DFT calculations and rationalize the results by quantitatively decomposing the anti/gauche isomerization energy into contributions from electrostatic, orbital, dispersion, and Pauli interactions, and energy spent on structural changes. The results show that the fluorine/sulfur gauche effect is primarily electrostatic (63-75%), while all orbital interactions contribute 22-41% to stabilizing interactions. Stereoelectronic effects, involved in orbital interactions, also play a role in gauche conformer stabilization.",
publisher = "Amer Chemical Soc, Washington",
journal = "Journal of Organic Chemistry",
title = "Origin of Fluorine/Sulfur Gauche Effect of beta-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion",
volume = "80",
number = "20",
pages = "10197-10207",
doi = "10.1021/acs.joc.5b01779"
}

Aleksić, J., Stojanović, M.,& Baranac-Stojanović, M.. (2015). Origin of Fluorine/Sulfur Gauche Effect of beta-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. in Journal of Organic Chemistry
Amer Chemical Soc, Washington., 80(20), 10197-10207.
https://doi.org/10.1021/acs.joc.5b01779

Aleksić J, Stojanović M, Baranac-Stojanović M. Origin of Fluorine/Sulfur Gauche Effect of beta-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. in Journal of Organic Chemistry. 2015;80(20):10197-10207.
doi:10.1021/acs.joc.5b01779 .

Aleksić, Jovana, Stojanović, Milovan, Baranac-Stojanović, Marija, "Origin of Fluorine/Sulfur Gauche Effect of beta-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion" in Journal of Organic Chemistry, 80, no. 20 (2015):10197-10207,
https://doi.org/10.1021/acs.joc.5b01779 . .

TY  - DATA
AU  - Aleksić, Jovana
AU  - Stojanović, Milovan
AU  - Baranac-Stojanović, Marija
PY  - 2015
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/3401
PB  - Amer Chemical Soc, Washington
T2  - Journal of Organic Chemistry
T1  - Supplementary data for article: Aleksić, J.; Stojanović, M.; Baranac-Stojanović, M. Origin of Fluorine/Sulfur Gauche Effect of β-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. Journal of Organic Chemistry 2015, 80 (20), 10197–10207. https://doi.org/10.1021/acs.joc.5b01779
UR  - https://hdl.handle.net/21.15107/rcub_cherry_3401
ER  - 

@misc{
author = "Aleksić, Jovana and Stojanović, Milovan and Baranac-Stojanović, Marija",
year = "2015",
publisher = "Amer Chemical Soc, Washington",
journal = "Journal of Organic Chemistry",
title = "Supplementary data for article: Aleksić, J.; Stojanović, M.; Baranac-Stojanović, M. Origin of Fluorine/Sulfur Gauche Effect of β-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. Journal of Organic Chemistry 2015, 80 (20), 10197–10207. https://doi.org/10.1021/acs.joc.5b01779",
url = "https://hdl.handle.net/21.15107/rcub_cherry_3401"
}

Aleksić, J., Stojanović, M.,& Baranac-Stojanović, M.. (2015). Supplementary data for article: Aleksić, J.; Stojanović, M.; Baranac-Stojanović, M. Origin of Fluorine/Sulfur Gauche Effect of β-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. Journal of Organic Chemistry 2015, 80 (20), 10197–10207. https://doi.org/10.1021/acs.joc.5b01779. in Journal of Organic Chemistry
Amer Chemical Soc, Washington..
https://hdl.handle.net/21.15107/rcub_cherry_3401

Aleksić J, Stojanović M, Baranac-Stojanović M. Supplementary data for article: Aleksić, J.; Stojanović, M.; Baranac-Stojanović, M. Origin of Fluorine/Sulfur Gauche Effect of β-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. Journal of Organic Chemistry 2015, 80 (20), 10197–10207. https://doi.org/10.1021/acs.joc.5b01779. in Journal of Organic Chemistry. 2015;.
https://hdl.handle.net/21.15107/rcub_cherry_3401 .

Aleksić, Jovana, Stojanović, Milovan, Baranac-Stojanović, Marija, "Supplementary data for article: Aleksić, J.; Stojanović, M.; Baranac-Stojanović, M. Origin of Fluorine/Sulfur Gauche Effect of β-Fluorinated Thiol, Sulfoxide, Sulfone, and Thionium Ion. Journal of Organic Chemistry 2015, 80 (20), 10197–10207. https://doi.org/10.1021/acs.joc.5b01779" in Journal of Organic Chemistry (2015),
https://hdl.handle.net/21.15107/rcub_cherry_3401 .

TY  - DATA
AU  - Stojanović, Milovan
AU  - Aleksić, Jovana
AU  - Baranac-Stojanović, Marija
PY  - 2015
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/3452
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Tetrahedron
T1  - Supplementary data for article: Stojanović, M.; Aleksić, J.; Baranac-Stojanović, M. The Effect of Steric Repulsion on the Torsional Potential of N-Butane: A Theoretical Study. Tetrahedron 2015, 71 (32), 5119–5123. https://doi.org/10.1016/j.tet.2015.06.002
UR  - https://hdl.handle.net/21.15107/rcub_cherry_3452
ER  - 

@misc{
author = "Stojanović, Milovan and Aleksić, Jovana and Baranac-Stojanović, Marija",
year = "2015",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Tetrahedron",
title = "Supplementary data for article: Stojanović, M.; Aleksić, J.; Baranac-Stojanović, M. The Effect of Steric Repulsion on the Torsional Potential of N-Butane: A Theoretical Study. Tetrahedron 2015, 71 (32), 5119–5123. https://doi.org/10.1016/j.tet.2015.06.002",
url = "https://hdl.handle.net/21.15107/rcub_cherry_3452"
}

Stojanović, M., Aleksić, J.,& Baranac-Stojanović, M.. (2015). Supplementary data for article: Stojanović, M.; Aleksić, J.; Baranac-Stojanović, M. The Effect of Steric Repulsion on the Torsional Potential of N-Butane: A Theoretical Study. Tetrahedron 2015, 71 (32), 5119–5123. https://doi.org/10.1016/j.tet.2015.06.002. in Tetrahedron
Pergamon-Elsevier Science Ltd, Oxford..
https://hdl.handle.net/21.15107/rcub_cherry_3452

Stojanović M, Aleksić J, Baranac-Stojanović M. Supplementary data for article: Stojanović, M.; Aleksić, J.; Baranac-Stojanović, M. The Effect of Steric Repulsion on the Torsional Potential of N-Butane: A Theoretical Study. Tetrahedron 2015, 71 (32), 5119–5123. https://doi.org/10.1016/j.tet.2015.06.002. in Tetrahedron. 2015;.
https://hdl.handle.net/21.15107/rcub_cherry_3452 .

Stojanović, Milovan, Aleksić, Jovana, Baranac-Stojanović, Marija, "Supplementary data for article: Stojanović, M.; Aleksić, J.; Baranac-Stojanović, M. The Effect of Steric Repulsion on the Torsional Potential of N-Butane: A Theoretical Study. Tetrahedron 2015, 71 (32), 5119–5123. https://doi.org/10.1016/j.tet.2015.06.002" in Tetrahedron (2015),
https://hdl.handle.net/21.15107/rcub_cherry_3452 .

TY  - JOUR
AU  - Stojanović, Milovan
AU  - Džambaski, Zdravko
AU  - Bondžić, Bojan
AU  - Aleksić, Jovana
AU  - Baranac-Stojanović, Marija
PY  - 2014
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/1810
AB  - 4-Oxothiazolidine core, owing to the wide range of pharmacological activities exhibited by its derivatives, has been recognized as an important structural motif in biologically active compounds. A subclass constitutes 4-oxothiazolidines with an exocyclic C=C double bond at the C(2)-position. Some of these derivatives are registered as active substances for the treatment of various diseases, such as Ralitoline, an antiepileptic, Etozolin, a diuretic, and Piprozolin, a choleretic. The exocyclic C=C double bond in these compounds contains one or two electron-accepting groups at its other end, so that they also belong to the class of the so-called push-pull alkenes. In the case of the nitrogen-unsubstituted molecules, the enamino tautomeric form with the exocyclic double bond is stabilized by the extended electron delocalization arising from the push-pull effect. In the absence of push-pull effect, the imino form would dominate. Therefore, these compounds exhibit properties characteristic for both 4-oxothiazolidine ring and push-pull alkenes. They are also proved to be useful synthetic interamediates for the formation of various mono- and polyheterocycles. The importance of 4-oxothiazolidine derivatives is witnessed by several review articles, the latest published in 2012, mainly dealing with the chemistry and biological activity of various 2-imino, 2-oxo, 2-thioxo and 2-alkyl(aryl)-substituted compounds. The lack of a comprehensive review on 2-alkylidene-4-oxothiazolidines has prompted us to collect the literature covering their synthesis, structure, reactivity and biological activity. Derivatives with two exocyclic C=C double bonds are included, too.
PB  - Bentham Science Publ Ltd, Sharjah
T2  - Current Organic Chemistry
T1  - 4-Oxothiazolidines with Exocyclic C=C Double Bond(s): Synthesis, Structure, Reactions and Biological Activity
VL  - 18
IS  - 9
SP  - 1108
EP  - 1148
DO  - 10.2174/138527281809140624120436
ER  - 

@article{
author = "Stojanović, Milovan and Džambaski, Zdravko and Bondžić, Bojan and Aleksić, Jovana and Baranac-Stojanović, Marija",
year = "2014",
abstract = "4-Oxothiazolidine core, owing to the wide range of pharmacological activities exhibited by its derivatives, has been recognized as an important structural motif in biologically active compounds. A subclass constitutes 4-oxothiazolidines with an exocyclic C=C double bond at the C(2)-position. Some of these derivatives are registered as active substances for the treatment of various diseases, such as Ralitoline, an antiepileptic, Etozolin, a diuretic, and Piprozolin, a choleretic. The exocyclic C=C double bond in these compounds contains one or two electron-accepting groups at its other end, so that they also belong to the class of the so-called push-pull alkenes. In the case of the nitrogen-unsubstituted molecules, the enamino tautomeric form with the exocyclic double bond is stabilized by the extended electron delocalization arising from the push-pull effect. In the absence of push-pull effect, the imino form would dominate. Therefore, these compounds exhibit properties characteristic for both 4-oxothiazolidine ring and push-pull alkenes. They are also proved to be useful synthetic interamediates for the formation of various mono- and polyheterocycles. The importance of 4-oxothiazolidine derivatives is witnessed by several review articles, the latest published in 2012, mainly dealing with the chemistry and biological activity of various 2-imino, 2-oxo, 2-thioxo and 2-alkyl(aryl)-substituted compounds. The lack of a comprehensive review on 2-alkylidene-4-oxothiazolidines has prompted us to collect the literature covering their synthesis, structure, reactivity and biological activity. Derivatives with two exocyclic C=C double bonds are included, too.",
publisher = "Bentham Science Publ Ltd, Sharjah",
journal = "Current Organic Chemistry",
title = "4-Oxothiazolidines with Exocyclic C=C Double Bond(s): Synthesis, Structure, Reactions and Biological Activity",
volume = "18",
number = "9",
pages = "1108-1148",
doi = "10.2174/138527281809140624120436"
}

Stojanović, M., Džambaski, Z., Bondžić, B., Aleksić, J.,& Baranac-Stojanović, M.. (2014). 4-Oxothiazolidines with Exocyclic C=C Double Bond(s): Synthesis, Structure, Reactions and Biological Activity. in Current Organic Chemistry
Bentham Science Publ Ltd, Sharjah., 18(9), 1108-1148.
https://doi.org/10.2174/138527281809140624120436

Stojanović M, Džambaski Z, Bondžić B, Aleksić J, Baranac-Stojanović M. 4-Oxothiazolidines with Exocyclic C=C Double Bond(s): Synthesis, Structure, Reactions and Biological Activity. in Current Organic Chemistry. 2014;18(9):1108-1148.
doi:10.2174/138527281809140624120436 .

Stojanović, Milovan, Džambaski, Zdravko, Bondžić, Bojan, Aleksić, Jovana, Baranac-Stojanović, Marija, "4-Oxothiazolidines with Exocyclic C=C Double Bond(s): Synthesis, Structure, Reactions and Biological Activity" in Current Organic Chemistry, 18, no. 9 (2014):1108-1148,
https://doi.org/10.2174/138527281809140624120436 . .

TY  - THES
AU  - Aleksić, Jovana
PY  - 2013
UR  - http://eteze.bg.ac.rs/application/showtheses?thesesId=1207
UR  - https://fedorabg.bg.ac.rs/fedora/get/o:8119/bdef:Content/download
UR  - http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=45194511
UR  - http://nardus.mpn.gov.rs/123456789/3501
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/2653
AB  - Halofilne reakcije predstavljaju vrstu nukleofilnih supstitucionih reakcija dokojih dolazi kada nukleofil reaguje sa atomom halogena, nakon ega se oslobaakarbanjon kao odlazea grupa. To su relativno rijetke reakcije koje se dešavaju ukolikoje klasina nukleofilna supstitucija (karbofilna reakcija) iz nekog razloga otežana i/ilikada je karbanjon stabilizovan prisustvom elektron-privlanih supstituenata.Cilj ovog rada je bio da se ispitaju halofilne reakcije i njihova sintetikaprimena na dva sistema: 2-alkiliden-4-oksotiazolidin vinil-bromidima i ,-dibrom-2-metoksiacetofenonu. Znaaj ovih reakcija u sluaju ispitivanih N-nesupstituisanihtiazolidinskih jedinjenja je u dobijanju novih, potencijalno biološki aktivnih C-5funkcionalizovanih derivata. Ovakvi derivati se ne mogu dobiti direktno reakcionomsekvencom C-5 bromovanje/nukleofilna supstitucija, jer je bromovanje Nnesupstituisanih2-alkiliden-4-oksotiazolidina visoko regioselektivno i kao proizvodi sedobijaju iskljuivo vinil-bromidi. Znaaj prouavanja ovakvih reakcija u sluaju a,a-dibrom-2-metoksiacetofenona proistie iz injenice da se selektivno a-monobromovanje metil-ketona esto teško postiže, a praeno je stvaranjem a,a-dibromderivatakao sporednih, a ponekad i kao glavnih proizvoda. Mogua kaskadnahalofilna/karbofilna reakcija bi omoguila korišenje dibrom-derivata kao sintetikihekvivalenta monobromida, ime bi se izbegla dodatna faza selektivnog debromovanjaradi dobijanja monobrom-derivata, kao znaajnih sintetikih intermedijera. Razliitineutralni i anjonski nukleofili su uestvovali u halofilnoj reakciji sa tiazolidinskim vinilbromidimadajui tri vrste proizvoda: i) proizvod reduktivnog debromovanja, ii)proizvod supstitucije broma i iii) C-5 funkcionalizovan proizvod. Takoe je pokazanoda se ,-dibrom-2-metoksiacetofenon može upotrebiti kao sintetiki ekvivalent a-monobromacetofenona.Pored navedenih halofilnih reakcija, u ovom radu ispitivana je i mogunostizvoenja Suzuki-Miyaura reakcije na vinil-bromidima, kao i mogua regioselektivnostove reakcije na N-supstituisanom tribrompirazolu, a u cilju dobijanja novih,potencijalno biološki aktivnih jedinjenja. Suzuki-Miyaura reakcija sa derivatimaarilbornih kiselina izvedena na vinil-bromidima nije dala oekivani rezultat, ali jeuspešno izvedena sa N-supstituisanim tribrompirazolima uz visoku regioselektivnost,pri emu su sintetisani 5-supstituisani 3,4-dibrompirazoli sa 1,1 ekvivalentom arilbornihkiselina, 3,5-disupstituisani 4-brompirazoli sa 2,2 ekvivalenta arilbornih kiselina i 3,4,5-trisupstituisani derivati sa 3,5 ekvivalenata arilbornih kiselina.S obzirom da ispitivani tiazolidini spadaju u grupu push-pull alkena, kod kojihelektronska delokalizacija izmeu donorskih i akceptorskih grupa na dvostrukoj veziima znaajan uticaj na njihove osobine i hemijsku reaktivnost, uraena je ikvantifikacija push-pull efekta dvostruke veze.
AB  - Halophilic reactions are nucleophilic substitution reactions in whichnucleophile attacks halogen atom with the carbanion acting as a leaving group. They arerelatively rare and usually take place if the classic nucleophilic substitution (carbophilicreaction) is made difficult, and/or if the resulting carbanion is stabilized by electronwithdrawingsubstituents.The aim of the present work was to study halophilic reactions and theirsynthetic application on two systems: 2-alkylidene-4-oxothiazolidines vinyl bromidesand ,-dibromo-2-methoxyacetophenone. The significance of the studied reactions inthe case of N-unsubstituited thiazolidine compounds would be the synthesis of novel,potentially biologically active C-5 substituted derivatives. These derivatives areimpossible to obtain directly by the C-5 bromination/SNC substitution reactionsequence, since bromination of N-unsubstituited 2-alkylidene-4-oxothiazolidines ishighly regioselective, resulting in the formation of vinyl bromides as sole products.Significance of the studied reactions in the case of ,-dibromo-2-methoxyacetophenone arises from the fact that selective a-monobromination of methylketones of often difficult to achieve. ,-Dibromo derivatives can be formed as sideproducts, or even as major ones. A possible cascade halophilic/carbophilic reactionwould allow the use of dibromo derivatives as synthetic equivalents of monobromocompounds, thus avoiding the additional step, selective debromination, necessary toobtain synthetically useful monobromo derivatives. Various neutral and anionicnucleophiles underwent a halophilic reaction with thiazolidine vinyl bromides yieldingthree types of products: i) products of reductive debromination, ii) bromine susbtitutionproducts and iii) C-5 functionalized products. It has also been shown that ,-dibromo-2-methoxyacetophenone can be used as synthetic equivalent of a-monobromoacetophenone.Apart from the mentioned halophilic reactions, a possibility of Suzuki-Miyaurareaction to take place with the vinyl bromides was investigated, along with the possibleregioselectivity of the same reaction applied to N-substituted tribromopyrazoles, all withthe aim to obtaine new, potentially biologically active compounds. Suzuki-Miyaurareaction of vinyl bromides with aryl boronic acid did not give the expectedtetrasubstituted alkenes. On the contrary, Suzuki-Miyaura reaction performed with theN-substituted tribromopyrazoles showed high regioselectivity yielding 5-substituted3,4-dibromopyrazoles with 1.1 equivalent of aryl boronic acids, 3,5-disubstituted 4-bromo derivatives with 2.2 equivalents of aryl boronic acids and 3,4,5-trisubstitutedderivatives with 3.5 equivalents of aryl boronic acids.Studied thiazolidine derivatives belong to the class of the so-called push-pullalkenes in which electronic delocalization beween donor and acceptor groups attachedat the C=C double bond highly influences their properties and chemical reactivity. Forthis reason, one aim of the present work was also to quantify this push-pull effect of thestudied compounds.
PB  - Универзитет у Београду, Хемијски факултет
T2  - Универзитет у Београду
T1  - 4-oksotiazolidin-2-alkiliden vinil-bromidi i α, α-dibrom-2-metoksiacetofenon : prekursori u sintetički korisnim transformacijama iniciranim retkim halofilnim napadom nukleofila
T1  - 4-oxothiazolidine-2-alkylidene vinyl bromides and a,a-dibromo-2-methoxyacetophenone: precursors in synthetically useful transformations initiated by the rare halophilic attack of nucleophiles
UR  - https://hdl.handle.net/21.15107/rcub_nardus_3501
ER  - 

@phdthesis{
author = "Aleksić, Jovana",
year = "2013",
abstract = "Halofilne reakcije predstavljaju vrstu nukleofilnih supstitucionih reakcija dokojih dolazi kada nukleofil reaguje sa atomom halogena, nakon ega se oslobaakarbanjon kao odlazea grupa. To su relativno rijetke reakcije koje se dešavaju ukolikoje klasina nukleofilna supstitucija (karbofilna reakcija) iz nekog razloga otežana i/ilikada je karbanjon stabilizovan prisustvom elektron-privlanih supstituenata.Cilj ovog rada je bio da se ispitaju halofilne reakcije i njihova sintetikaprimena na dva sistema: 2-alkiliden-4-oksotiazolidin vinil-bromidima i ,-dibrom-2-metoksiacetofenonu. Znaaj ovih reakcija u sluaju ispitivanih N-nesupstituisanihtiazolidinskih jedinjenja je u dobijanju novih, potencijalno biološki aktivnih C-5funkcionalizovanih derivata. Ovakvi derivati se ne mogu dobiti direktno reakcionomsekvencom C-5 bromovanje/nukleofilna supstitucija, jer je bromovanje Nnesupstituisanih2-alkiliden-4-oksotiazolidina visoko regioselektivno i kao proizvodi sedobijaju iskljuivo vinil-bromidi. Znaaj prouavanja ovakvih reakcija u sluaju a,a-dibrom-2-metoksiacetofenona proistie iz injenice da se selektivno a-monobromovanje metil-ketona esto teško postiže, a praeno je stvaranjem a,a-dibromderivatakao sporednih, a ponekad i kao glavnih proizvoda. Mogua kaskadnahalofilna/karbofilna reakcija bi omoguila korišenje dibrom-derivata kao sintetikihekvivalenta monobromida, ime bi se izbegla dodatna faza selektivnog debromovanjaradi dobijanja monobrom-derivata, kao znaajnih sintetikih intermedijera. Razliitineutralni i anjonski nukleofili su uestvovali u halofilnoj reakciji sa tiazolidinskim vinilbromidimadajui tri vrste proizvoda: i) proizvod reduktivnog debromovanja, ii)proizvod supstitucije broma i iii) C-5 funkcionalizovan proizvod. Takoe je pokazanoda se ,-dibrom-2-metoksiacetofenon može upotrebiti kao sintetiki ekvivalent a-monobromacetofenona.Pored navedenih halofilnih reakcija, u ovom radu ispitivana je i mogunostizvoenja Suzuki-Miyaura reakcije na vinil-bromidima, kao i mogua regioselektivnostove reakcije na N-supstituisanom tribrompirazolu, a u cilju dobijanja novih,potencijalno biološki aktivnih jedinjenja. Suzuki-Miyaura reakcija sa derivatimaarilbornih kiselina izvedena na vinil-bromidima nije dala oekivani rezultat, ali jeuspešno izvedena sa N-supstituisanim tribrompirazolima uz visoku regioselektivnost,pri emu su sintetisani 5-supstituisani 3,4-dibrompirazoli sa 1,1 ekvivalentom arilbornihkiselina, 3,5-disupstituisani 4-brompirazoli sa 2,2 ekvivalenta arilbornih kiselina i 3,4,5-trisupstituisani derivati sa 3,5 ekvivalenata arilbornih kiselina.S obzirom da ispitivani tiazolidini spadaju u grupu push-pull alkena, kod kojihelektronska delokalizacija izmeu donorskih i akceptorskih grupa na dvostrukoj veziima znaajan uticaj na njihove osobine i hemijsku reaktivnost, uraena je ikvantifikacija push-pull efekta dvostruke veze., Halophilic reactions are nucleophilic substitution reactions in whichnucleophile attacks halogen atom with the carbanion acting as a leaving group. They arerelatively rare and usually take place if the classic nucleophilic substitution (carbophilicreaction) is made difficult, and/or if the resulting carbanion is stabilized by electronwithdrawingsubstituents.The aim of the present work was to study halophilic reactions and theirsynthetic application on two systems: 2-alkylidene-4-oxothiazolidines vinyl bromidesand ,-dibromo-2-methoxyacetophenone. The significance of the studied reactions inthe case of N-unsubstituited thiazolidine compounds would be the synthesis of novel,potentially biologically active C-5 substituted derivatives. These derivatives areimpossible to obtain directly by the C-5 bromination/SNC substitution reactionsequence, since bromination of N-unsubstituited 2-alkylidene-4-oxothiazolidines ishighly regioselective, resulting in the formation of vinyl bromides as sole products.Significance of the studied reactions in the case of ,-dibromo-2-methoxyacetophenone arises from the fact that selective a-monobromination of methylketones of often difficult to achieve. ,-Dibromo derivatives can be formed as sideproducts, or even as major ones. A possible cascade halophilic/carbophilic reactionwould allow the use of dibromo derivatives as synthetic equivalents of monobromocompounds, thus avoiding the additional step, selective debromination, necessary toobtain synthetically useful monobromo derivatives. Various neutral and anionicnucleophiles underwent a halophilic reaction with thiazolidine vinyl bromides yieldingthree types of products: i) products of reductive debromination, ii) bromine susbtitutionproducts and iii) C-5 functionalized products. It has also been shown that ,-dibromo-2-methoxyacetophenone can be used as synthetic equivalent of a-monobromoacetophenone.Apart from the mentioned halophilic reactions, a possibility of Suzuki-Miyaurareaction to take place with the vinyl bromides was investigated, along with the possibleregioselectivity of the same reaction applied to N-substituted tribromopyrazoles, all withthe aim to obtaine new, potentially biologically active compounds. Suzuki-Miyaurareaction of vinyl bromides with aryl boronic acid did not give the expectedtetrasubstituted alkenes. On the contrary, Suzuki-Miyaura reaction performed with theN-substituted tribromopyrazoles showed high regioselectivity yielding 5-substituted3,4-dibromopyrazoles with 1.1 equivalent of aryl boronic acids, 3,5-disubstituted 4-bromo derivatives with 2.2 equivalents of aryl boronic acids and 3,4,5-trisubstitutedderivatives with 3.5 equivalents of aryl boronic acids.Studied thiazolidine derivatives belong to the class of the so-called push-pullalkenes in which electronic delocalization beween donor and acceptor groups attachedat the C=C double bond highly influences their properties and chemical reactivity. Forthis reason, one aim of the present work was also to quantify this push-pull effect of thestudied compounds.",
publisher = "Универзитет у Београду, Хемијски факултет",
journal = "Универзитет у Београду",
title = "4-oksotiazolidin-2-alkiliden vinil-bromidi i α, α-dibrom-2-metoksiacetofenon : prekursori u sintetički korisnim transformacijama iniciranim retkim halofilnim napadom nukleofila, 4-oxothiazolidine-2-alkylidene vinyl bromides and a,a-dibromo-2-methoxyacetophenone: precursors in synthetically useful transformations initiated by the rare halophilic attack of nucleophiles",
url = "https://hdl.handle.net/21.15107/rcub_nardus_3501"
}

Aleksić, J.. (2013). 4-oksotiazolidin-2-alkiliden vinil-bromidi i α, α-dibrom-2-metoksiacetofenon : prekursori u sintetički korisnim transformacijama iniciranim retkim halofilnim napadom nukleofila. in Универзитет у Београду
Универзитет у Београду, Хемијски факултет..
https://hdl.handle.net/21.15107/rcub_nardus_3501

Aleksić J. 4-oksotiazolidin-2-alkiliden vinil-bromidi i α, α-dibrom-2-metoksiacetofenon : prekursori u sintetički korisnim transformacijama iniciranim retkim halofilnim napadom nukleofila. in Универзитет у Београду. 2013;.
https://hdl.handle.net/21.15107/rcub_nardus_3501 .

Aleksić, Jovana, "4-oksotiazolidin-2-alkiliden vinil-bromidi i α, α-dibrom-2-metoksiacetofenon : prekursori u sintetički korisnim transformacijama iniciranim retkim halofilnim napadom nukleofila" in Универзитет у Београду (2013),
https://hdl.handle.net/21.15107/rcub_nardus_3501 .