物理化学学报Issue(5)：852-858,7.DOI:10.3866/PKU.WHXB201503026
铁催化芳基格氏试剂的联芳交叉偶联的反应机理
Reaction Mechanism for the Iron-Catalyzed Biaryl Cross-Coupling of Aryl Grignard Reagents
摘要
Abstract
Mechanisms for the [Fe(MgBr)2] catalyzed cross-coupling reaction between ortho-chlorostyrene and phenylmagnesium bromide to form biaryl were studied using density functional theory (DFT) calculations. We investigated two mechanisms. Cycle A included three basic steps:(I) oxidation of [Fe(MgBr)2] to obtain [Ar-Fe(MgBr)], (II) addition to yield [Ar-(phenyl)-Fe(MgBr)2], and (III) reductive elimination to return to [Fe(MgBr)2]. Cycle B did not form [Ar-Fe(MgBr)]. In the first step, phenylmagnesium bromide attacks the intermediate of the oxidative addition directly before [Cl-Mg-Br] dissociates to form [Ar-Fe(MgBr)]. The catalytic Cycle B is favored over the catalytic Cycle A when considering the solvent effect. The rate-limiting step in the overal catalytic cycle for both Cycle A and Cycle B is the reductive elimination of [Ar-(phenyl)-Fe(MgBr)2] to regenerate the catalyst [Fe(MgBr)2], where the Gibbs free energy in solvent tetrahydrofuran (THF), ∆Gsol, is 82.98 kJ∙mol-1, as determined using the conductor polarized continuum model (CPCM) method.关键词
铁催化剂/联芳/交叉偶联/反应机理/密度泛函理论Key words
Iron catalyst/Biaryl/Cross-coupling/Reaction mechanism/Density functional theory分类
化学化工引用本文复制引用
任清华,沈晓燕..铁催化芳基格氏试剂的联芳交叉偶联的反应机理[J].物理化学学报,2015,(5):852-858,7.基金项目
The project was supported by the High Performance Computing Platform of Shanghai University, China and Shanghai Higher Education Connotation Construction“085”Project“Materials Genome Engineering”Funding, China (B.58-B111-12-101, B.58-B111-12-103).上海大学高性能计算平台“自强4000”与上海市高等教育内涵建设“085”工程“材料基因工程”项目(B.58-B111-12-101, B.58-B111-12-103)资助 （B.58-B111-12-101, B.58-B111-12-103）
