Intermolecular addition reactions of N-alkyl-N-chlorosulfonamides to unsaturated compounds

Abstract

Summary N-Alkyl-N-chlorosulfonamides add to alkenes under copper(I) catalysis. In reactions of styrene derivatives with terminal double bonds the addition products were obtained in excellent yield and high regioselectivity. Lower yields are obtained in addition reactions to non-aromatic alkenes. The reaction most likely proceeds via a redox catalysis and amidyl radicals, a concerted mechanism has been ruled out and a polar mechanism via chloronium ions would lead to the opposite regiochemistry.

Intermolecular Anti-Markovnikov Hydroamination of Unactivated Alkenes with Sulfonamides Enabled by Proton-Coupled Electron Transfer

“…In a recent report describing a directed C–H alkylation method, we demonstrated that an N -radical species derived from the PCET activation of a 2° sulfon­amide could activate distal aliphatic C–H bonds via 1,5-hydrogen atom transfer (HAT). As sulfon­amide-derived radicals are known to undergo olefin addition with high levels of anti-Markovnikov regio­selectivity, we reasoned that this approach might serve as the basis for a new regio­selective hydro­amination method.…”