A metal-catalyzed new approach for α-alkynylation of cyclic amines

Yifan Cui; Weilong Lin; Shengming Ma

doi:10.1039/c8sc04115f

A metal-catalyzed new approach for α-alkynylation of cyclic amines

Chem Sci. 2018 Nov 26;10(6):1796-1801. doi: 10.1039/c8sc04115f. eCollection 2019 Feb 14.

Authors

Yifan Cui^{1

2}, Weilong Lin^{1

2}, Shengming Ma^{1

3}

Affiliations

¹ State Key Laboratory of Organometallic Chemistry , Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Lu , Shanghai 200032 , P. R. China . Email: masm@sioc.ac.cn.
² University of Chinese Academy of Sciences , Beijing 100049 , P. R. China.
³ Department of Chemistry , Fudan University , 220 Handan Lu , Shanghai 200433 , P. R. China.

Abstract

The first catalytic α-alkynylation of cyclic amines with the help of the N-propargylic group to afford 2-(1-alkynyl) N-allylic cyclic amines with an exclusive E-stereoselectivity for the in situ formed C[double bond, length as m-dash]C bond has been realized. Based on mechanistic studies, it is proven that the reaction proceeds through metal-mediated anti-1,5-hydride transfer forming an iminonium intermediate, which accepts the addition of the in situ generated 1-alkynyl metal species. The synthetic application has also been demonstrated.