Metal triflate-mediated coupling of allylgermanes with thiols: a facile route to thiogermanes†
A novel coupling reaction of thiols with (2-methylallyl)germanes catalyzed by metal triflates has been developed. This reaction provides a direct and efficient method to afford thiogermanes and opens a valuable and general synthetic route for the Ge–S cross-coupling with the elimination of isobutylene as a single by-product. Scandium(III) triflate demonstrates the highest catalytic activity among the tested triflates. All reactions were carried out under extremely mild conditions to give thiogermanes in excellent yields. This Ge–S coupling reaction shows high generality for the variety of thiols.