Reactions of o-Aminothiophenol and o-Aminophenyl Disulfide with Itaconic Anhydride and (-)-Dimenthyl Itaconate: Access to Enantiomerically Pure 1,5-Benzothiazepines and Benzothiazolyl-2-methylacrylic Acid1

摘要

A facile chemo- and regioselective reactions of o-ami-nothiophenol (o-ATP) with itaconic anhydride is described. 1,5-Benzothiazepinyl-3-acetic acid is obtained in 81% yield via the exclusive Michael type addition of the thiol unit from o-ATP to the carbon-carbon double bond in itaconic anhydride followed by an intramolecular anhydride ring opening with an amine unit. The moderately stereoselective Michael type addition of the thiol unit from o-ATP to (-)-dimenthyl itaconate to obtain a mixture of dia-stereomers in a 7:3 ratio in 82% yield has been demonstrated. The reductive sulfur-sulfur bond cleavage in the dicarboxylic acid, 2-({2-[2-(3-carboxybut-3-enoylamino)phenyldisulfanyl]phenylcar-bamoyl}methyl)acrylic acid, to the corresponding benzothiazolyl-2-methylacrylic acid in 84% yield, instead of the desired benzothio-azocine is also reported