The first enantioselective catalytic approach to cis- and trans-2,3-diaryl substituted 1,5-benzothiazepines has been conveniently developed in a one-pot fashion, starting from α,β-unsaturated acyl pyrazoles and 2-aminothiophenol. The organocatalytic two-step sulfa-Michael/lactamization sequence is promoted by a readily available bifunctional thiourea and p-toluenesulfonic acid, respectively. The protocol
Oxazepines and Thiazepines, XXV: Chemical Transformations of 2,3-Dihydro-1,5-benzothiazepin-4(5H)-ones
作者:Albert Lévai
DOI:10.1002/ardp.19923251108
日期:——
2,3‐Dihydro‐1,5‐benzothiazepine‐4(5H)‐thiones 13‐22 were prepared by the reaction of the appropriate 2,3‐dihydro‐1,5‐benzothiazepin‐4(5H)‐ones with Lawesson's reagent. N‐Acyl (23‐25) and N‐alkyl (26‐28) derivatives have also been synthesized. Oxidation with 3‐chloroperoxybenzoic acid afforded sulfoxides 29‐32, and sulfones 33‐40 were obtained by using H2O2 as an oxidizing agent.