Synergistic Bimetallic Ni/Ag and Ni/Cu Catalysis for Regioselective γ,δ-Diarylation of Alkenyl Ketimines: Addressing β-H Elimination by in Situ Generation of Cationic Ni(II) Catalysts
作者:Prakash Basnet、Shekhar KC、Roshan K. Dhungana、Bijay Shrestha、Timothy J. Boyle、Ramesh Giri
DOI:10.1021/jacs.8b09401
日期:2018.11.21
We disclose unprecedented synergistic bimetallic Ni/Ag and Ni/Cu catalysts for regioselective γ,δ-diarylation of unactivated alkenes in simple ketimines with aryl halides and arylzinc reagents. The bimetallic synergy, which generates cationic Ni(II) species during reaction, promotes migratory insertion and transmetalation steps and suppresses β-H elimination and cross-coupling, the major side reactions
我们公开了前所未有的协同双金属 Ni/Ag 和 Ni/Cu 催化剂,用于在简单的酮亚胺中与芳基卤化物和芳基锌试剂对未活化的烯烃进行区域选择性 γ,δ-二芳基化。双金属协同作用在反应过程中产生阳离子 Ni(II) 物质,促进迁移插入和金属转移步骤,并抑制 β-H 消除和交叉偶联,这是在烯烃双官能化过程中导致严重问题的主要副反应。这种二芳基化反应在偏远的地方进行到亚胺,在简单的 H+ 处理后,得到不同取代的 γ,δ-二芳基酮,否则很难用现有方法轻松获得。