Density Functional Theory Studies on the Mechanism of the Reduction of CO2 to CO Catalyzed by Copper(l) Boryl Complexes.
The detailed reaction mechanism for the reduction of CO to CO catalyzed by (NHC)Cu(boryl) complexes (NHC = N-heterocyclic carbene) was studied with the aid of DFT by calculating the relevant intermediates and transition state structures. Our DFT calculations show that the reaction occurs through CO...
| Publicado en: | Journal of the American Chemical Society Vol. 128; no. 49; pp. 15637 - 15644 |
|---|---|
| Autores principales: | , , |
| Formato: | Artículo |
| Publicado: |
American Chemical Society
12/13/2006
|
| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=23520237&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 23520237 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 12/13/2006 vid: 128 iid: 49 pid: 997 pub: American Chemical Society artinfo: ui: 23520237 10.1021/ja063671r ppf: 15637 ppct: 7 formats: tig: atl: Density Functional Theory Studies on the Mechanism of the Reduction of CO2 to CO Catalyzed by Copper(l) Boryl Complexes. aug: au: Haitao Zhao Zhenyang Lin Marder, Todd B. affil: Department of Chemistry and Open Laboratory of Chirotechnology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong Department of Chemistry, Durham University, South Road, Durham DHJ 3LE, U.K. su: Density functionals Reaction mechanisms (Chemistry) Copper compounds Functional analysis Conditions & laws of chemical reaction Physical & theoretical chemistry sug: subj: Density functionals Reaction mechanisms (Chemistry) Copper compounds Functional analysis Conditions & laws of chemical reaction Physical & theoretical chemistry ab: The detailed reaction mechanism for the reduction of CO to CO catalyzed by (NHC)Cu(boryl) complexes (NHC = N-heterocyclic carbene) was studied with the aid of DFT by calculating the relevant intermediates and transition state structures. Our DFT calculations show that the reaction occurs through CO insertion into the CuB bond to give a CuOC(O)-boryl species (i.e., containing CuO and CB bonds), and subsequent boryl migration from C to O, followed by o-bond metathesis between pinB-Bpin (Bpin, pin = pinacolate = OCMeCMeO) and (NHC)Cu(OBpin). The overall reaction is exergonic by 38.0 kcal/mol. It is the nucleophilicity of the CuB bond, a function of the very strong σ-donor properties of the boryl ligand, rather than the oxophilicity of boron, which determines the direction of the CO insertion process. The boryl migration from C to O, which releases the product CO, is the rate-determining step and involves the ‘vacant’ orbital orbital on boron. The (NHC)Cu(boryl) complexes show unique activity in the catalytic process. For the analogous (NHC)Cu(alkyl) complexes, the CO insertion into the CuC bond giving a copper acetate intermediate occurs with a readily achievable barrier. However, the elimination of CO from the acetate intermediate through a methyl migration from C to O is energetically inaccessible. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2006 holdings: @attributes: islocal: N |
|---|