Synthesis of 4-Aryl-4-methyl- and 4,4-Dimethyl-4H-pyrrolo[2,1-c][1,4]benzothiazines by an Easy Five-Step Sequence Starting from 2-Sulfanylbenzenamines

Abstract

A convenient process for the synthesis of 4-aryl-4-methyl- and 4,4-dimethyl-4H-pyrrolo[2,1-c][1,4]benzothiazines has been developed. Cyclization of 1-{2-[1-aryl(or methyl)ethenylsulfanyl]phenyl}pyrroles, which are readily obtained by an easy four-step sequence starting from commercially available 2-sulfanylbenzenamines, to the desired heterocycles can be effected in good to excellent yields on treatment with a catalytic amount of hydriodic acid.

Key words

4H-pyrrolo[2,1-c][1,4]benzothiazines - 2-sulfanylbenzenamines - hydriodic acid - magnesium amide - sulfur-stabilized carbenium ion

• References

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