One pot regioselective synthesis of a small library of dibenzo[b,f][1,4]thiazepin-11(10H)-ones via Smiles rearrangement.

A facile and efficient method has been developed for the synthesis of a small library of dibenzo[b,f][1,4]thiazepin-11(10H)-ones via Smiles rearrangement. Compounds were obtained in excellent isolated yields (70%–92%) under metal-free conditions. More specifically, this transition metal-free process relates to an environmentally friendly, economical, and efficient method for preparing benzoic-fused seven-membered lactams.