Aromatic heteroannulation via metalation-cyclization of N-acyl-2-chlorobenzenesulfonamides and N-acylbenzenesulfonamides

…, JA Campbell, TD Greenwood, JA Lewis…

Index: Hermann, Christine K. F.; Campbell, James A.; Greenwood, Thomas D.; Lewis, Judith A.; Wolfe, James F. Journal of Organic Chemistry, 1992 , vol. 57, # 20 p. 5328 - 5334

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Citation Number: 16

Abstract

N-Acyl-2-chlorobenzeneaulfonamidea 7a-d undergo competitive metal-halogen exchange and orthedeprotonation or a-deprotonation reactions when treated sequentially with sodium hydride and n-butyllithium. The o-lithio intermediates derived from metal-halogen exchange and ortho-deprotonation undergo cyclization to afford 3-substituted 1, 8benzisothiazole 1, l- dioxides 1Oa-d and 3-substituted 7-chloro-1, 2-benzisothiazole 1, l-dioxides 14a-d, ...