title: Theoretical investigation on the chemoselective N-heterocyclic carbene-catalyzed cross-benzoin reactions.
abstract: A density functional theory study was performed to understand the detailed mechanisms of the cross-benzoin reactions catalyzed by N-heterocyclic carbene (NHC) species. Our theoretical study predicted that the first H-transfer operates with water in solution as a mediator, and the second H-transfer undergoes a concerted mechanism rather than a stepwise one. In addition, the chemoselectivity of the reactions studied in this work has been explored. P1 was obtained as a major product mainly due to the more stable intermediate formed by reaction of NHC with reactant R1. Different steric effects resulting from the fused six-membered ring in transition state TS7 and the fused five-membered ring in transition state TS13 are the origin leading to the chemoselectivity.
authors: Department of Chemistry and Chemical Engineering, Key Lab of Inorganic Chemistry, Shandong Provincial Education Department, Jining University, Qufu 273155, Shandong, China.
authors: Tao
authors: T
authors: Liu
authors: Shu-Min
authors: SM
authors: Han
authors: Ling-Li
authors: LL
authors: Han
authors: Lu
authors: L
authors: Wang
authors: Xiang-Yang
authors: XY
authors: Cui
authors: Chong-Yang
authors: CY
authors: Du
authors: Siwei
authors: S
authors: Bi
mesh_terms: D001573:Benzoin / Q000737:chemistry*; D002384:Catalysis; D006571:Heterocyclic Compounds / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D008962:Models, Theoretical; D008968:Molecular Conformation; D013816:Thermodynamics
chemical_list: D006571:Heterocyclic Compounds; C030011:carbene; D001573:Benzoin; D008697:Methane