title: Transannular Anti-Michael Addition: Formation of 4H-Pyrazolo[5,1-c]thiazines.
abstract: The reaction of 2-(diphenylmethylene)thietan-3-one (2) with 1,2,4,5-tetrazines (3a-c) in KOH/MeOH/THF gives 4H-pyrazolo[5,1-c]thiazines (7a-c). This no vel condensation reaction proceeds via the intermediacy of an 8-(diphenylmethylene)-2H-1,4,5-thiadiazocin-7(8H)-one (5), which undergoes a multi-step rearrangement including a rare anti-Michael addition.
authors: Department of Chemistry, University of California, Davis, CA 95616, USA.
authors: Yat Fan
authors: YF
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authors: H
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