Reactions of Arylpropynehydrazides with Substituted Malonyl Chlorides: A Route to Pyrazolo-Condensed 1,3-Oxazines
作者:Olga A. Petina、Igor P. Yakovlev、Detlef Geffken
DOI:10.1002/ejoc.201200267
日期:2012.6
Reaction of phenylpropynehydrazide with dimethylmalonyl chloride furnished the corresponding 4,4-dimethyl-1-(3-phenylprop-2-ynoyl)pyrazolidine-3,5-dione, which upon thermolysis underwent a 6-endo-dig cyclization to a pyrazolo[5,1-b][1,3]oxazine. The corresponding reaction of arylpropynehydrazides with monosubstituted malonyl chlorides furnished pyrazolo[5,1-b][1,3]oxazine-7-ones via intermediates that
苯丙炔酰肼与二甲基丙二酰氯反应得到相应的 4,4-二甲基-1-(3-苯基丙-2-炔酰基)吡唑烷-3,5-二酮,其在热解后经历 6-endo-dig 环化生成吡唑 [5] ,1-b][1,3]恶嗪。芳基丙炔酰肼与单取代丙二酰氯的相应反应通过无法分离的中间体提供吡唑并[5,1-b][1,3]恶嗪-7-酮。