TY  - JOUR
AU  - Yan, Zhiqing
AU  - McCracken, Troy
AU  - Xia, Shijing
AU  - Maslak, Veselin
AU  - Gallucci, Judith
AU  - Hadad, Christopher M.
AU  - Bađić, Jovica D.
PY  - 2008
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/899
AB  - [GRAPHICS] The supramolecular assistance to Pd(0)/Cu(I)-catalyzed cyclotrimerization of stannylated norbornene 7 has been investigated to give molecular bowl 1(syn) in a stereoselective fashion. Following a divergent strategy, racemic norbornene 7 was synthesized in satisfactory yield. Self-coupling, promoted by Pd(0)/Cu(I) catalysis acting in synergy with CsF, yielded molecular bowl 1(syn) in a moderate 30% yield. The reaction diastereoselectivity is affected by the concentration of Cu(I) and Cs+: increasing quantities of the cations enhanced the synlanti ratio of the isolated cyclotrimer from statistical (1:3) to a more desirable (4.5:1) ratio, in favor of the molecular bowl 1(syn) H-1 NMR spectroscopic studies suggested the coordinating affinity of 1(syn) toward transition metals Cu(I), Ag(I), and Au(I), to account for the observed templation effect. In particular, the tridentate 1(syn) has been shown to bind to one Ag(I) cation in the assembly process that is driven with enthalpy (Delta H-0 = - 19 +/- 2 kcal/mol, Delta S-0 = -45 eu). The complete coordination was not cooperative, and was hypothesized to be impeded with the adverse entropy. Accordingly, density functional theory (BP86) calculations of 1(syn) and its mono-, bis-, and tris-Ag(I) complexes suggested that the coordination of one to three silver cations is highly exothermic. The calculations also revealed that the bowl constriction is necessary for the aromatic arms to become preorganized and bind to a silver cation(s) (Delta E approximate to 8 kcal/mol). Ultimately, Ag(I) has been shown to assist the diastereoselective formation of lending support to the notion, of template-directed synthesis.
PB  - Amer Chemical Soc, Washington
T2  - Journal of Organic Chemistry
T1  - Supramolecular catalysis at work: Diastereoselective synthesis of a molecular bowl with dynamic inner space
VL  - 73
IS  - 2
SP  - 355
EP  - 363
DO  - 10.1021/jo701538g
ER  - 

@article{
author = "Yan, Zhiqing and McCracken, Troy and Xia, Shijing and Maslak, Veselin and Gallucci, Judith and Hadad, Christopher M. and Bađić, Jovica D.",
year = "2008",
abstract = "[GRAPHICS] The supramolecular assistance to Pd(0)/Cu(I)-catalyzed cyclotrimerization of stannylated norbornene 7 has been investigated to give molecular bowl 1(syn) in a stereoselective fashion. Following a divergent strategy, racemic norbornene 7 was synthesized in satisfactory yield. Self-coupling, promoted by Pd(0)/Cu(I) catalysis acting in synergy with CsF, yielded molecular bowl 1(syn) in a moderate 30% yield. The reaction diastereoselectivity is affected by the concentration of Cu(I) and Cs+: increasing quantities of the cations enhanced the synlanti ratio of the isolated cyclotrimer from statistical (1:3) to a more desirable (4.5:1) ratio, in favor of the molecular bowl 1(syn) H-1 NMR spectroscopic studies suggested the coordinating affinity of 1(syn) toward transition metals Cu(I), Ag(I), and Au(I), to account for the observed templation effect. In particular, the tridentate 1(syn) has been shown to bind to one Ag(I) cation in the assembly process that is driven with enthalpy (Delta H-0 = - 19 +/- 2 kcal/mol, Delta S-0 = -45 eu). The complete coordination was not cooperative, and was hypothesized to be impeded with the adverse entropy. Accordingly, density functional theory (BP86) calculations of 1(syn) and its mono-, bis-, and tris-Ag(I) complexes suggested that the coordination of one to three silver cations is highly exothermic. The calculations also revealed that the bowl constriction is necessary for the aromatic arms to become preorganized and bind to a silver cation(s) (Delta E approximate to 8 kcal/mol). Ultimately, Ag(I) has been shown to assist the diastereoselective formation of lending support to the notion, of template-directed synthesis.",
publisher = "Amer Chemical Soc, Washington",
journal = "Journal of Organic Chemistry",
title = "Supramolecular catalysis at work: Diastereoselective synthesis of a molecular bowl with dynamic inner space",
volume = "73",
number = "2",
pages = "355-363",
doi = "10.1021/jo701538g"
}

Yan, Z., McCracken, T., Xia, S., Maslak, V., Gallucci, J., Hadad, C. M.,& Bađić, J. D.. (2008). Supramolecular catalysis at work: Diastereoselective synthesis of a molecular bowl with dynamic inner space. in Journal of Organic Chemistry
Amer Chemical Soc, Washington., 73(2), 355-363.
https://doi.org/10.1021/jo701538g

Yan Z, McCracken T, Xia S, Maslak V, Gallucci J, Hadad CM, Bađić JD. Supramolecular catalysis at work: Diastereoselective synthesis of a molecular bowl with dynamic inner space. in Journal of Organic Chemistry. 2008;73(2):355-363.
doi:10.1021/jo701538g .

Yan, Zhiqing, McCracken, Troy, Xia, Shijing, Maslak, Veselin, Gallucci, Judith, Hadad, Christopher M., Bađić, Jovica D., "Supramolecular catalysis at work: Diastereoselective synthesis of a molecular bowl with dynamic inner space" in Journal of Organic Chemistry, 73, no. 2 (2008):355-363,
https://doi.org/10.1021/jo701538g . .

TY  - JOUR
AU  - Wang, Bao-Yu
AU  - Bao, Xiaoguang
AU  - Yan, Zhiqing
AU  - Maslak, Veselin
AU  - Hadad, Christopher M.
AU  - Bađić, Jovica D.
PY  - 2008
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/981
AB  - Molecular basket 1, composed of a semirigid tris-norbornadiene framework and three revolving pyridine-based gates at the rim, has been built to "dynamically" enclose space and as such regulate molecular encapsulation. The gates were shown to fold via intramolecular hydrogen bonding and thereby form a G(3v) symmetrical receptor: the (1)H NMR resonance for the amide N-H protons of the pyridine gates appeared downfield (delta = 10.98 ppm), and the N-H vibrational stretch (IR) was observed at 3176 cm(-1). Accordingly, density functional theory (DFT, B3LYP) investigations revealed for the closed conformers of 1 to be energetically the most stable and dominant. The gearing of the pyridine "gates", about their axis, led to the interconversion of two dynamic enantiomers 1(A) and 1(B) comprising the clockwise and counterclockwise seam of intramolecular hydrogen bonds. Dynamic (1)H NMR spectroscopic measurements and line-shape simulations suggested that the energy barrier of 10.0 kcal/mol (Delta G(A/B)(double dagger), 298 K) is required for the 1(A/B) interconversion, when CCl(4) occupies the cavity of 1. Likewise, the activation free energy for CCl4 departing the basket was found to be 13.1 kcal/mol (Delta G(double dagger), 298 K), whereas the thermodynamic stability of 1:CCl(4) complex was -2.7 kcal/mol (Delta G degrees, 298 K). In view of that, CCI4 (but also (CH(3))(3)CBr) was proposed to escape from, and a molecule of solvent to enter, the basket when the gates rotate about their axis: the exit of CCl(4) requires the activation energy of 12.7 kcal/mol (Delta G(A/B)(double dagger) + Delta G degrees), similar to the experimentally found 13.1 kcal/mol (Delta G(double dagger)).
PB  - Amer Chemical Soc, Washington
T2  - Journal of the American Chemical Society
T1  - A 3-fold "Butterfly Valve" in Command of the Encapsulation's Kinetic Stability. Molecular Baskets at Work
VL  - 130
IS  - 45
SP  - 15127
EP  - 15133
DO  - 10.1021/ja8041977
ER  - 

@article{
author = "Wang, Bao-Yu and Bao, Xiaoguang and Yan, Zhiqing and Maslak, Veselin and Hadad, Christopher M. and Bađić, Jovica D.",
year = "2008",
abstract = "Molecular basket 1, composed of a semirigid tris-norbornadiene framework and three revolving pyridine-based gates at the rim, has been built to "dynamically" enclose space and as such regulate molecular encapsulation. The gates were shown to fold via intramolecular hydrogen bonding and thereby form a G(3v) symmetrical receptor: the (1)H NMR resonance for the amide N-H protons of the pyridine gates appeared downfield (delta = 10.98 ppm), and the N-H vibrational stretch (IR) was observed at 3176 cm(-1). Accordingly, density functional theory (DFT, B3LYP) investigations revealed for the closed conformers of 1 to be energetically the most stable and dominant. The gearing of the pyridine "gates", about their axis, led to the interconversion of two dynamic enantiomers 1(A) and 1(B) comprising the clockwise and counterclockwise seam of intramolecular hydrogen bonds. Dynamic (1)H NMR spectroscopic measurements and line-shape simulations suggested that the energy barrier of 10.0 kcal/mol (Delta G(A/B)(double dagger), 298 K) is required for the 1(A/B) interconversion, when CCl(4) occupies the cavity of 1. Likewise, the activation free energy for CCl4 departing the basket was found to be 13.1 kcal/mol (Delta G(double dagger), 298 K), whereas the thermodynamic stability of 1:CCl(4) complex was -2.7 kcal/mol (Delta G degrees, 298 K). In view of that, CCI4 (but also (CH(3))(3)CBr) was proposed to escape from, and a molecule of solvent to enter, the basket when the gates rotate about their axis: the exit of CCl(4) requires the activation energy of 12.7 kcal/mol (Delta G(A/B)(double dagger) + Delta G degrees), similar to the experimentally found 13.1 kcal/mol (Delta G(double dagger)).",
publisher = "Amer Chemical Soc, Washington",
journal = "Journal of the American Chemical Society",
title = "A 3-fold "Butterfly Valve" in Command of the Encapsulation's Kinetic Stability. Molecular Baskets at Work",
volume = "130",
number = "45",
pages = "15127-15133",
doi = "10.1021/ja8041977"
}

Wang, B., Bao, X., Yan, Z., Maslak, V., Hadad, C. M.,& Bađić, J. D.. (2008). A 3-fold "Butterfly Valve" in Command of the Encapsulation's Kinetic Stability. Molecular Baskets at Work. in Journal of the American Chemical Society
Amer Chemical Soc, Washington., 130(45), 15127-15133.
https://doi.org/10.1021/ja8041977

Wang B, Bao X, Yan Z, Maslak V, Hadad CM, Bađić JD. A 3-fold "Butterfly Valve" in Command of the Encapsulation's Kinetic Stability. Molecular Baskets at Work. in Journal of the American Chemical Society. 2008;130(45):15127-15133.
doi:10.1021/ja8041977 .

Wang, Bao-Yu, Bao, Xiaoguang, Yan, Zhiqing, Maslak, Veselin, Hadad, Christopher M., Bađić, Jovica D., "A 3-fold "Butterfly Valve" in Command of the Encapsulation's Kinetic Stability. Molecular Baskets at Work" in Journal of the American Chemical Society, 130, no. 45 (2008):15127-15133,
https://doi.org/10.1021/ja8041977 . .

TY  - JOUR
AU  - Yan, Zhiqing
AU  - Xia, Shijing
AU  - Gardlik, Matthew
AU  - Seo, Wanji
AU  - Maslak, Veselin
AU  - Gallucci, Judith
AU  - Hadad, Christopher M.
AU  - Bađić, Jovica D.
PY  - 2007
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/835
AB  - We have investigated Ag(I) mediated folding of a tridentate compound, containing three pyridine flaps tethered to a semirigid scaffold, into a molecular basket, using both experimental and theoretical methods. The basket formation has been shown to be highly favorable in organic media (Delta G degrees = -7.2 kcal/mol), with the assembly process allowing for another ligand to bind preferentially on the outer side.
PB  - Amer Chemical Soc, Washington
T2  - Organic Letters
T1  - Silver(I) mediated folding of a molecular basket
VL  - 9
IS  - 12
SP  - 2301
EP  - 2304
DO  - 10.1021/ol0705595
ER  - 

@article{
author = "Yan, Zhiqing and Xia, Shijing and Gardlik, Matthew and Seo, Wanji and Maslak, Veselin and Gallucci, Judith and Hadad, Christopher M. and Bađić, Jovica D.",
year = "2007",
abstract = "We have investigated Ag(I) mediated folding of a tridentate compound, containing three pyridine flaps tethered to a semirigid scaffold, into a molecular basket, using both experimental and theoretical methods. The basket formation has been shown to be highly favorable in organic media (Delta G degrees = -7.2 kcal/mol), with the assembly process allowing for another ligand to bind preferentially on the outer side.",
publisher = "Amer Chemical Soc, Washington",
journal = "Organic Letters",
title = "Silver(I) mediated folding of a molecular basket",
volume = "9",
number = "12",
pages = "2301-2304",
doi = "10.1021/ol0705595"
}

Yan, Z., Xia, S., Gardlik, M., Seo, W., Maslak, V., Gallucci, J., Hadad, C. M.,& Bađić, J. D.. (2007). Silver(I) mediated folding of a molecular basket. in Organic Letters
Amer Chemical Soc, Washington., 9(12), 2301-2304.
https://doi.org/10.1021/ol0705595

Yan Z, Xia S, Gardlik M, Seo W, Maslak V, Gallucci J, Hadad CM, Bađić JD. Silver(I) mediated folding of a molecular basket. in Organic Letters. 2007;9(12):2301-2304.
doi:10.1021/ol0705595 .

Yan, Zhiqing, Xia, Shijing, Gardlik, Matthew, Seo, Wanji, Maslak, Veselin, Gallucci, Judith, Hadad, Christopher M., Bađić, Jovica D., "Silver(I) mediated folding of a molecular basket" in Organic Letters, 9, no. 12 (2007):2301-2304,
https://doi.org/10.1021/ol0705595 . .

TY  - JOUR
AU  - Yan, Zhiqing
AU  - Chang, Yuning
AU  - Mayo, Dennis
AU  - Maslak, Veselin
AU  - Xia, Shijing
AU  - Bađić, Jovica D.
PY  - 2006
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/795
AB  - Inspired by allostery in nature, we synthesized cavitand 1 and investigated regulation of its conformational dynamics. Quantitative H-1 NMR studies have revealed that the rate of the conformational isomerization of 1 can be modulated using the external addition of acid. As 1 maintains its vase-like conformation in an acidic environment, ample opportunities for controlling the kinetics of molecular recognition, and thus reactivity, in this and related receptors have arisen.
PB  - Amer Chemical Soc, Washington
T2  - Organic Letters
T1  - Allosteric regulation of the conformational dynamics of a cavitand receptor
VL  - 8
IS  - 17
SP  - 3697
EP  - 3700
DO  - 10.1021/ol0612760
ER  - 

@article{
author = "Yan, Zhiqing and Chang, Yuning and Mayo, Dennis and Maslak, Veselin and Xia, Shijing and Bađić, Jovica D.",
year = "2006",
abstract = "Inspired by allostery in nature, we synthesized cavitand 1 and investigated regulation of its conformational dynamics. Quantitative H-1 NMR studies have revealed that the rate of the conformational isomerization of 1 can be modulated using the external addition of acid. As 1 maintains its vase-like conformation in an acidic environment, ample opportunities for controlling the kinetics of molecular recognition, and thus reactivity, in this and related receptors have arisen.",
publisher = "Amer Chemical Soc, Washington",
journal = "Organic Letters",
title = "Allosteric regulation of the conformational dynamics of a cavitand receptor",
volume = "8",
number = "17",
pages = "3697-3700",
doi = "10.1021/ol0612760"
}

Yan, Z., Chang, Y., Mayo, D., Maslak, V., Xia, S.,& Bađić, J. D.. (2006). Allosteric regulation of the conformational dynamics of a cavitand receptor. in Organic Letters
Amer Chemical Soc, Washington., 8(17), 3697-3700.
https://doi.org/10.1021/ol0612760

Yan Z, Chang Y, Mayo D, Maslak V, Xia S, Bađić JD. Allosteric regulation of the conformational dynamics of a cavitand receptor. in Organic Letters. 2006;8(17):3697-3700.
doi:10.1021/ol0612760 .

Yan, Zhiqing, Chang, Yuning, Mayo, Dennis, Maslak, Veselin, Xia, Shijing, Bađić, Jovica D., "Allosteric regulation of the conformational dynamics of a cavitand receptor" in Organic Letters, 8, no. 17 (2006):3697-3700,
https://doi.org/10.1021/ol0612760 . .

TY  - CONF
AU  - Yan, Zhiqing
AU  - Chang, Yuning
AU  - Maslak, Veselin
AU  - Mayo, Dennis
AU  - Bađić, Jovica D.
PY  - 2006
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/523
PB  - Amer Chemical Soc, Washington
C3  - ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY
T1  - ORGN 793-Modulating conformational dynamics of a cavitand using an external stimulus
VL  - 232
UR  - https://hdl.handle.net/21.15107/rcub_cherry_523
ER  - 

@conference{
author = "Yan, Zhiqing and Chang, Yuning and Maslak, Veselin and Mayo, Dennis and Bađić, Jovica D.",
year = "2006",
publisher = "Amer Chemical Soc, Washington",
journal = "ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY",
title = "ORGN 793-Modulating conformational dynamics of a cavitand using an external stimulus",
volume = "232",
url = "https://hdl.handle.net/21.15107/rcub_cherry_523"
}

Yan, Z., Chang, Y., Maslak, V., Mayo, D.,& Bađić, J. D.. (2006). ORGN 793-Modulating conformational dynamics of a cavitand using an external stimulus. in ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY
Amer Chemical Soc, Washington., 232.
https://hdl.handle.net/21.15107/rcub_cherry_523

Yan Z, Chang Y, Maslak V, Mayo D, Bađić JD. ORGN 793-Modulating conformational dynamics of a cavitand using an external stimulus. in ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY. 2006;232.
https://hdl.handle.net/21.15107/rcub_cherry_523 .

Yan, Zhiqing, Chang, Yuning, Maslak, Veselin, Mayo, Dennis, Bađić, Jovica D., "ORGN 793-Modulating conformational dynamics of a cavitand using an external stimulus" in ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 232 (2006),
https://hdl.handle.net/21.15107/rcub_cherry_523 .