Lewis acid mediated reaction of N-phenyl-S-(4-methylphenyl)sulfoximidoyl chloride with alkenes
摘要:
The reaction of N-phenyl-S-(4-methylphenyl)sulfoximidoyl chloride (1) with alkenes in the presence of aluminum chloride leads to 2,1-benzothiazines in good yield. The reaction is regioselective, sometimes highly stereoselective, and is stereospecific with respect to alkene geometry. The mechanism can be formulated as a concerted cycloaddition between the iminosulfonium species 2 and the alkene to form a sigma-complex that subsequently rearomatizes to give the product.