Ring Expansion of Thiazolidine and Nucleophilic Substitution in N-Acyl Derivatives of 6-Thia-3,8-diazabicyclo[3.2.1. ]octan-2-one1
نویسنده
چکیده
Reaction of N3,N8-diacyl 6-thia-3,8-diazabicyclo/3.2. l./octan-2-one (I) with PC15 or S02Cl2 gave 6-chloro substituted N2,N5-diacyl 7-thia-2,5-diazabicyclo/2.2.2./octan-3-one (II). Treatment of II with water yielded the 6-hydroxy derivative (III) while reaction with methanol gave the 6-methoxy derivative (IV). Under the same reaction conditions the mono N8-acyl derivative (V) gave a mixture of 6-substituted 7-thia-2,5-diazabicyclo/2.2.2./octan-3-one and 4-su bsti tuted 6-thia-3,8-diazabicyclo/3.2. l ./octan-2-one derivatives (XIV and XV ; VI and VII; VIII and IX) . It was proposed that ring expansion of thiazolidine and nucleophilic substitution occured vi a the thiiranium ion XIII as a common interm ediate.
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