<i>Trans</i>‐Selective Radical Silylzincation of Ynamides

Abstract

Abstract The silylzincation of terminal ynamides is achieved through a radical‐chain process involving (Me 3 Si) 3 SiH and R 2 Zn. A potentially competing polar mechanism is excluded on the basis of diagnostic control experiments. The unique feature of this addition across the CC bond is its trans selectivity. One‐pot electrophilic substitution of the C Zn bond by Cu I ‐mediated CC bond formation and subsequent manipulation of the C Si bond provides a modular access to Z‐α,β‐disubstituted enamides.