Mechanistic Study of Nickel-Catalyzed Reductive Coupling of Ynoates and Aldehydes
作者:Sanjeewa K. Rodrigo、Hairong Guan
DOI:10.1021/acs.joc.7b00483
日期:2017.5.19
reductive coupling of ynoates and aldehydes with triethylsilane. The catalytic reaction of ethyl 3-(trimethylsilyl)propiolate and methyl 4-formylbenzoate shows first-order dependence on aldehyde and catalyst concentrations, inverse first-order dependence on [ynoate], and no dependence on [silane]. The kinetics data, coupled with deuterium-labeling experiments, support a mechanism involving dissociation of
在这项工作中,使用(1,5-己二烯)Ni(SIPr)(SIPr = 1,3-双(2,6-二异丙基苯基)咪唑烷基-2-亚甲基)代替Ni(COD)2 / SIPr·HBF 4 /吨Bu(COD = 1,5-环辛二烯)作为更稳健的催化剂,可用于壬酸酯和醛与三乙基硅烷的区域选择性还原偶联。3-(三甲基甲硅烷基)丙酸乙酯和4-甲酰基苯甲酸甲酯的催化反应显示出对醛和催化剂浓度的一阶依赖性,对[叶酸酯]的逆一阶依赖性,而不对[硅烷]的依赖性。动力学数据与氘标记实验相结合,支持了一种机制,该机制涉及在限制营业额形成催化活性镍二氢呋喃之前,从催化休眠的镍环戊二烯中间体解离酸酯。