Catalyst-free tandem reaction of 2,2′-diaminodiphenyldisulfides, sulfinic acids and aromatic aldehydes: an approach to synthesize unsymmetric thiosulfonates and benzothiazoles†
Abstract
A facile, efficient and green synthetic method for the preparation of unsymmetric S-(2-aminophenyl) arenethiosulfonates and 2-arylbenzothiazoles through a tandem reaction of 2,2′-diaminodiphenyldisulfides, sulfinic acids and aromatic aldehydes was developed. Mechanistic studies demonstrate that the NH2 group in disulfides has a positive influence on the tandem reaction, and simultaneous cyclization and coupling transformations can be completed after the homolysis of disulfides. This tandem reaction shows a broad substrate scope and a good functional group tolerance. A large number of products have been prepared in good to excellent yields under metal- and catalyst-free conditions with good atom economy.