Synthesis of substituted 3-phenyl-6<i>h</i>-pyrazolo[4,3-d]isoxazoles from corresponding 4-benzoyl-5-hydroxypyrazoles
作者:Wolfgang Holzer、Katharina Hahn
DOI:10.1002/jhet.5570400216
日期:2003.3
Treatment of 1,(3)-(di)substituted 4-benzoyl-5-hydroxypyrazoles with phosphorus oxychloride affords the corresponding 4-benzoyl-5-chloropyrazoles. Reaction of the latter with hydroxylamine leads to oximes, which can be cyclized to novel 3-phenyl-6H-pyrazolo[4,3-d]isoxazoles by treatment with sodiumhydride in dimethyl formamide. Detailed nmr spectroscopic studies (1H, 13C) with all obtained compounds
用氯氧化磷处理1,(3)-(二)取代的4-苯甲酰基-5-羟基吡唑,得到相应的4-苯甲酰基-5-氯吡唑。后者与羟胺的反应生成肟,可以通过在二甲基甲酰胺中用氢化钠处理将其环化为新型3-苯基-6 H-吡唑并[4,3- d ]异恶唑。介绍了使用所有获得的化合物进行的详细NMR光谱研究(1 H,13 C)。