有机金属试剂对 3-位双(硅基)N-酰基吡啶鎓的区域选择性亲核加成反应。

Regioselective nucleophilic addition of organometallic reagents to 3-geminal bis(silyl) N-acyl pyridinium.

机构信息

Key Laboratory of Drug-Targeting of Education Ministry and Department of Medicinal Chemistry, West China School of Pharmacy, ‡State Key Laboratory of Biotherapy, West China Hospital, §Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University , Chengdu 610041, P. R. China.

出版信息

Org Lett. 2014 Apr 4;16(7):1880-3. doi: 10.1021/ol500302r. Epub 2014 Mar 25.

DOI:10.1021/ol500302r

PMID:24666415

Abstract

A regioselective nucleophilic addition to 3-geminal bis(silyl) N-acyl pyridinium has been described. Geminal bis(silane) shows contrasting roles that lead to different regioselectivities for the addition of different nucleophiles: its steric effect dominates to favor 1,6-addition of alkyl, vinyl, and aryl organometallic reagents; its directing effect dominates to favor 1,2-addition of less sterically demanding alkynyl Grignard reagents.

摘要

已描述了 3-偕二（硅基）N-酰基吡啶鎓的区域选择性亲核加成。偕二硅烷表现出相反的作用，导致不同亲核试剂的加成具有不同的区域选择性：其空间位阻效应占主导地位，有利于烷基、乙烯基和芳基有机金属试剂的 1,6-加成；其导向效应占主导地位，有利于空间位阻要求较低的炔基格氏试剂的 1,2-加成。