Heterocyeles' Ring-Opening in Reactions of 3-Methyl-4-nitro-3-thiolene-l,l-dioxide with Substituted Hydrazines

摘要

4-Nitro-3-thiolene-1,1 -dioxides are the active heterocyclic sulfonitroalkenes able to interact with nucleo-philes by the addition, vinyl substitution or salt formation pathways. The direction and effectiveness of these processes are determined by the nature of the substituents in the sulfolene ring, the reagents nature, and the reaction conditions [1,2]. Thus, the addition of arylamines to the multiple bond of 3-methyl-4-nitro-3-thiolene-1,1-dioxide I proceeds in refluxing ethanol. More active nucleophiles, aroylhydrazines, react atroom temperature to give corresponding Michael adducts [3]. Tightening of the reaction conditions of nitrothiolene dioxide I with benzoylhydrazine at equimolar ratio in refluxing ethanol unexpectedly results in the formation of the novel open-chain structure, (2-nitroethylsulfonyl)propanone benzoylhydra-zone II. The reactions of nitrosulfolene I with the more basic substituted hydrazines, semicarbazide and phenylhydrazine, give rise to similar linear nitro-alkylsulfones III and IV even at room temperature.