SYNTHESIS OF THIENOTHIAZOCINOISOINDOLEDIONES AND THIENOTHIAZINOISOINDOLONES FROM MERCAPTOTHIOPHENES AND CHLOROMETHYLPHTHALIMIDE

2-Thienylthiomethylphthalimides 3a,b were synthesized by action of chl oromethylphthalimide on 2-or 3-mercaptothiophene. Reduction of 3a,b an d Wittig reaction using carbethoxycarbonyltriphenylphosphorane gave th e corresponding acetic acids 5a,b which cyclized under Friedel and Cra fts conditions to lead the thienothiazocinoisoindolediones 6a,b. Thien othiazinoisoindolones 7a,b were obtained from hydroxyisoindolones deri vatives 4a,b in acid conditions via an acyliminium ion.