Synthesis of alkynyl sulfides resulting from a novel ring cleavage of 5-chloro-1,2,3-thiadiazoles in the presence of organometallic reagents

Abstract

5-Chloro-1,2,3-thiadiazoles 2a,b were treated with organolithium and Grignard reagents giving a novel ring cleavage with the loss of nitrogen and chloride anion, resulting in the formation of alkynyl sulfides 9–14. The results indicate that the mechanism of the reaction involves a concerted trans-elimination of the leaving group.

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