Conjugated azoalkenes. Part XI. Direct synthesis of substituted pyrazoles and 4-triphenylphosphoranylidene-4,5-dihydropyrazol-5-ones by heterocyclization of some zwitterionic 1,4-adducts between conjugated azoalkenes and triphenylphosphine
作者:Orazio A. Attanasi、Paolino Filippone、Amedeo Mei
DOI:10.1016/s0040-4020(01)88729-9
日期:1992.2
The simple and direct synthesis in good yields of substituted pyrazoles and 4-triphenylphosphoranylidene-4,5-dihydropyrazol-5-ones is reported. These products have been prepared by heterocyclization under different reaction conditions of some 1,5-zwitterionic species obtained from the 1,4-conjugate addition of triphenylphosphine to the azo-ene system of conjugated azoalkenes.
据报道,以简单的产率合成了简单且直接的合成的取代的吡唑和4-三苯基膦亚基-4,5-二氢吡唑-5-酮。这些产物是通过在不同反应条件下杂环化而制得的,这些物质是由三苯基膦的1,4-共轭加成到共轭偶氮烯烃的偶氮-烯体系中而得到的一些1,5-两性离子物质。