Theoretical studies of inorganic and organometallic reaction mechanisms 13: Methane, ethylene, and acetylene activation at a Cationic Iridium Center
Апстракт
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.
Извор:
ACS Symposium Series / American Chemical Society, 1999, 721, 138-150Колекције
Институција/група
Hemijski fakultet / Faculty of ChemistryTY - 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 .