TfOH-catalyzed PPh3-promoted nucleophilic cyclization reactions for the synthesis of functionalized (Z)-2-imino-benzo[e][1,3]thiazin-4-ones

Abstract

The first example of an effective TfOH-catalyzed PPh₃-promoted nucleophilic cyclization reaction for the synthesis of (Z)-2-imino-benzo[e ][1,3]thiazin-4-ones via benzo [c] [1,2]dithiol-3-ones and carbodiimides have been developed. The nucleophilic cyclization reaction offers new concise routes to access various functionalized (Z)-2-imino-benzothiazinones in moderate to excellent yields under mild reaction conditions, which are of biological and synthetic importance.