Enantioselective Copper-Catalyzed Remote C(sp³)–H Alkynylation of Linear Primary Sulfonamides

Abstract

The highly efficient copper-catalyzed enantioselective alkynylation of the remote C(sp3)–H bond on linear primary sulfonamides is presented here using a radical relay strategy. The chiral box–copper complex, which is used to recapture the in-situ-generated alkyl radical via a 1,5-HAT strategy, is the key to success, affording the chiral alkynes after a following reductive elimination. A general substrate scope, mild conditions, and excellent regio- and enantioselective control are demonstrated in this method.