Metal- and phosphine-free electrophilic vicinal chloro-alkylthiolation and trifluoromethylthiolation of indoles using sodium sulfinate in the presence of triphosgene

Abstract

Efficient chloro-alkylthiolation and trifluoromethylthiolation of indole derivatives were developed. Triphosgene was used as a reducing agent for the first time to convert sodium sulfinate to highly active electrophilic intermediates (CH₃SCl and CF₃SOCl). This strategy involves the use of cheap and readily available reagents and has broad substrate scope.