TY  - JOUR
AU  - Niu, Shuqiang
AU  - Strout, D.L.
AU  - Zarić, Snežana D.
AU  - Bayse, C.A.
AU  - Hall, Michael B.
PY  - 1999
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/63
AB  - The oxidative-addition/reductive-elimination (OA/RE) reactions of methane, ethylene and acetylene with the CpIr(PH3)(CH3)+ complex are investigated by ab initio methods and density functional theory (DFT). The calculated results shows that the OA reaction from CpIr(PH3)(CH3)(agostic-alkane)+ to CpIr(PH3)(CH3)(H)(alkyl)+ is endothermic by 4.4 and 0.8 kcal/mol with a low barrier of 11.5 and 10.0 kcal/mol at the DFT-B3LYP and coupled cluster with singles and doubles (CCSD) levels of theory, respectively. The RE reaction from CpIr(PH3)(CH3)(H)(alkyl)+ to a β-agostic complex, CpIr(PH3)(alkyl)+, is exothermic with a low barrier of 7.1 and 9.2 kcal/mol. A strong stabilizing interaction between either ethylene or acetylene and CpIr(PH3)(CH3)+ leads to a high activation barrier (24-36 kcal/mol) for the OA processes of either one. Compared to ethylene, the OA/RE reaction of acetylene with CpIr(PH3)(CH3)+ complex is more favorable. Thus, the dimerization of terminal alkynes catalyzed by cationic iridium complexes is plausible.
T2  - ACS Symposium Series / American Chemical Society
T1  - Theoretical studies of inorganic and organometallic reaction mechanisms 13: Methane, ethylene, and acetylene activation at a Cationic Iridium Center
VL  - 721
SP  - 138
EP  - 150
UR  - https://hdl.handle.net/21.15107/rcub_cherry_63
ER  - 

@article{
author = "Niu, Shuqiang and Strout, D.L. and Zarić, Snežana D. and Bayse, C.A. and Hall, Michael B.",
year = "1999",
abstract = "The oxidative-addition/reductive-elimination (OA/RE) reactions of methane, ethylene and acetylene with the CpIr(PH3)(CH3)+ complex are investigated by ab initio methods and density functional theory (DFT). The calculated results shows that the OA reaction from CpIr(PH3)(CH3)(agostic-alkane)+ to CpIr(PH3)(CH3)(H)(alkyl)+ is endothermic by 4.4 and 0.8 kcal/mol with a low barrier of 11.5 and 10.0 kcal/mol at the DFT-B3LYP and coupled cluster with singles and doubles (CCSD) levels of theory, respectively. The RE reaction from CpIr(PH3)(CH3)(H)(alkyl)+ to a β-agostic complex, CpIr(PH3)(alkyl)+, is exothermic with a low barrier of 7.1 and 9.2 kcal/mol. A strong stabilizing interaction between either ethylene or acetylene and CpIr(PH3)(CH3)+ leads to a high activation barrier (24-36 kcal/mol) for the OA processes of either one. Compared to ethylene, the OA/RE reaction of acetylene with CpIr(PH3)(CH3)+ complex is more favorable. Thus, the dimerization of terminal alkynes catalyzed by cationic iridium complexes is plausible.",
journal = "ACS Symposium Series / American Chemical Society",
title = "Theoretical studies of inorganic and organometallic reaction mechanisms 13: Methane, ethylene, and acetylene activation at a Cationic Iridium Center",
volume = "721",
pages = "138-150",
url = "https://hdl.handle.net/21.15107/rcub_cherry_63"
}

Niu, S., Strout, D.L., Zarić, S. D., Bayse, C.A.,& Hall, M. B.. (1999). Theoretical studies of inorganic and organometallic reaction mechanisms 13: Methane, ethylene, and acetylene activation at a Cationic Iridium Center. in ACS Symposium Series / American Chemical Society, 721, 138-150.
https://hdl.handle.net/21.15107/rcub_cherry_63

Niu S, Strout D, Zarić SD, Bayse C, Hall MB. Theoretical studies of inorganic and organometallic reaction mechanisms 13: Methane, ethylene, and acetylene activation at a Cationic Iridium Center. in ACS Symposium Series / American Chemical Society. 1999;721:138-150.
https://hdl.handle.net/21.15107/rcub_cherry_63 .

Niu, Shuqiang, Strout, D.L., Zarić, Snežana D., Bayse, C.A., Hall, Michael B., "Theoretical studies of inorganic and organometallic reaction mechanisms 13: Methane, ethylene, and acetylene activation at a Cationic Iridium Center" in ACS Symposium Series / American Chemical Society, 721 (1999):138-150,
https://hdl.handle.net/21.15107/rcub_cherry_63 .

TY  - JOUR
AU  - Niu, SQ
AU  - Zarić, Snežana D.
AU  - Bayse, CA
AU  - Strout, DL
AU  - Hall, Michael B.
PY  - 1998
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/399
AB  - Recent experimental work shows that alkanes can be activated by Cp*Ir(PMe3)(CH3)(+) at room temperature to generate olefin complexes. The reaction begins with alkane activation by oxidative addition (OA) followed by reductive elimination (RE) of methane and then olefin formation by the beta-H transfer from the bound alkyl. Ab initio calculations and density functional theory (DFT) studies of ethane activation by CpIr(PH3)(CH3)(+) (1) to generate CpIr(PH3)(eta(2)-C2H4)(H)(+) (7) show that the beta-H transfer from CpIr(PH3)(C2H5)(+) (5) to 7 is exothermic by 12 and 16 kcal/mol with a very low barrier of 0.7 and 0.4 kcal/mol at the DFT and CCSD levels, respectively. Thus, the rate-determining step in alkane dehydrogenation to olefin complexes by Cp*Ir(PMe3)(CH3)(+) is the alkane OA step. These results are in very good agreement with the experimental work of Bergman and co-workers. A strong stabilizing interaction between either ethylene or acetylene and CpIr(PH3)(CH3)(+) leads to high activation barriers (25-36 kcal/mol) for the insertion processes of ethylene or acetylene. In comparison to ethylene, the insertion reaction of acetylene with the CpIr(PH3)(CH3)(+) complex is more favorable. Thus, the dimerization of terminal alkynes catalyzed by cationic iridium complexes is plausible.
PB  - Amer Chemical Soc, Washington
T2  - Organometallics
T1  - Theoretical studies of inorganic and organometallic reaction mechanisms. 14. beta-hydrogen transfer and alkene/alkyne insertion at a cationic iridium center
VL  - 17
IS  - 23
SP  - 5139
EP  - 5147
DO  - 10.1021/om980429n
ER  - 

@article{
author = "Niu, SQ and Zarić, Snežana D. and Bayse, CA and Strout, DL and Hall, Michael B.",
year = "1998",
abstract = "Recent experimental work shows that alkanes can be activated by Cp*Ir(PMe3)(CH3)(+) at room temperature to generate olefin complexes. The reaction begins with alkane activation by oxidative addition (OA) followed by reductive elimination (RE) of methane and then olefin formation by the beta-H transfer from the bound alkyl. Ab initio calculations and density functional theory (DFT) studies of ethane activation by CpIr(PH3)(CH3)(+) (1) to generate CpIr(PH3)(eta(2)-C2H4)(H)(+) (7) show that the beta-H transfer from CpIr(PH3)(C2H5)(+) (5) to 7 is exothermic by 12 and 16 kcal/mol with a very low barrier of 0.7 and 0.4 kcal/mol at the DFT and CCSD levels, respectively. Thus, the rate-determining step in alkane dehydrogenation to olefin complexes by Cp*Ir(PMe3)(CH3)(+) is the alkane OA step. These results are in very good agreement with the experimental work of Bergman and co-workers. A strong stabilizing interaction between either ethylene or acetylene and CpIr(PH3)(CH3)(+) leads to high activation barriers (25-36 kcal/mol) for the insertion processes of ethylene or acetylene. In comparison to ethylene, the insertion reaction of acetylene with the CpIr(PH3)(CH3)(+) complex is more favorable. Thus, the dimerization of terminal alkynes catalyzed by cationic iridium complexes is plausible.",
publisher = "Amer Chemical Soc, Washington",
journal = "Organometallics",
title = "Theoretical studies of inorganic and organometallic reaction mechanisms. 14. beta-hydrogen transfer and alkene/alkyne insertion at a cationic iridium center",
volume = "17",
number = "23",
pages = "5139-5147",
doi = "10.1021/om980429n"
}

Niu, S., Zarić, S. D., Bayse, C., Strout, D.,& Hall, M. B.. (1998). Theoretical studies of inorganic and organometallic reaction mechanisms. 14. beta-hydrogen transfer and alkene/alkyne insertion at a cationic iridium center. in Organometallics
Amer Chemical Soc, Washington., 17(23), 5139-5147.
https://doi.org/10.1021/om980429n

Niu S, Zarić SD, Bayse C, Strout D, Hall MB. Theoretical studies of inorganic and organometallic reaction mechanisms. 14. beta-hydrogen transfer and alkene/alkyne insertion at a cationic iridium center. in Organometallics. 1998;17(23):5139-5147.
doi:10.1021/om980429n .

Niu, SQ, Zarić, Snežana D., Bayse, CA, Strout, DL, Hall, Michael B., "Theoretical studies of inorganic and organometallic reaction mechanisms. 14. beta-hydrogen transfer and alkene/alkyne insertion at a cationic iridium center" in Organometallics, 17, no. 23 (1998):5139-5147,
https://doi.org/10.1021/om980429n . .

TY  - JOUR
AU  - Strout, DL
AU  - Zarić, Snežana D.
AU  - Niu, SQ
AU  - Hall, Michael B.
PY  - 1996
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/2242
PB  - Amer Chemical Soc, Washington
T2  - Journal of the American Chemical Society
T1  - Methane metathesis at a Cationic Iridium Center
VL  - 118
IS  - 25
SP  - 6068
EP  - 6069
DO  - 10.1021/ja961057h
ER  - 

@article{
author = "Strout, DL and Zarić, Snežana D. and Niu, SQ and Hall, Michael B.",
year = "1996",
publisher = "Amer Chemical Soc, Washington",
journal = "Journal of the American Chemical Society",
title = "Methane metathesis at a Cationic Iridium Center",
volume = "118",
number = "25",
pages = "6068-6069",
doi = "10.1021/ja961057h"
}

Strout, D., Zarić, S. D., Niu, S.,& Hall, M. B.. (1996). Methane metathesis at a Cationic Iridium Center. in Journal of the American Chemical Society
Amer Chemical Soc, Washington., 118(25), 6068-6069.
https://doi.org/10.1021/ja961057h

Strout D, Zarić SD, Niu S, Hall MB. Methane metathesis at a Cationic Iridium Center. in Journal of the American Chemical Society. 1996;118(25):6068-6069.
doi:10.1021/ja961057h .

Strout, DL, Zarić, Snežana D., Niu, SQ, Hall, Michael B., "Methane metathesis at a Cationic Iridium Center" in Journal of the American Chemical Society, 118, no. 25 (1996):6068-6069,
https://doi.org/10.1021/ja961057h . .