异腈化合物插入到配合物CpW(NO)(n-C5H11)(η3-CH2CHCHMe)金属-碳键的反应机理

摘要

本文利用密度泛函理论研究了异睛化合物中CN基团插入到CpW(NO)(C5H11)(η3-CH2CHCHMe)(A)中W-C键中的反应机制.研究发现,异腈插入到W-C键过程实际上是一个烷基迁移过程；相对于烯丙基,正戊基迁移到异腈碳原子上在热力学、动力学上更有利.提出了插入产物(B)与其环状异构体(C)之间的平衡转化机理,同时发现C为Fischer型金属卡宾配合物,金属中心具有d6电子构型.%With the aid of density functional theory calculations, the mechanistic study on the insertion of CN of methylisonitrile into the M-C bond of CpW(NO)(C5H11)(773-CH2CHCHMe) (A) has been performed. It is found that the methylisonitrile insertion into metal-alkyl linkage is in fact a process of the alkyl (-C5Hn) migration into methylisonitrile. In comparison with the allyl group, the alkyl (-C5Hn) migration into methylisonitrile is more favorable both kinetically and thermodynamically. The mechanism for the reversible transformation between the insertion product B and it's cyclic isomer C has been proposed. C is found to be a Fischer carbene complex with the metal center having a d6 configuration.