Intermediacy of an N-Heterocyclic Carbene Complex in the Catalytic C−H Activation of a Substituted Benzimidazole
作者:Kian L. Tan、Robert G. Bergman、Jonathan A. Ellman
DOI:10.1021/ja017351d
日期:2002.4.1
An N-heterocyclic carbene complex was found to be the active catalyst in the Rh(I)-catalyzed intramolecular coupling of an alkenyl group to a C-H bond of a substituted benzimidazole. Kinetic studies demonstrated that the catalytic cyclization is zero-order in substrate and first-order in catalyst. Furthermore, DFT calculations with a model system suggest that the rate-limiting step involves insertion
发现 N-杂环卡宾配合物是 Rh(I) 催化的烯基与取代苯并咪唑的 CH 键的分子内偶联中的活性催化剂。动力学研究表明,催化环化在底物上是零级的,在催化剂上是一级的。此外,模型系统的 DFT 计算表明,限速步骤涉及将烯基双键插入铑-卡宾键中。