hydroxypyrazoles (2a–f) and 2-methyl-3-isoxazolones (3a–d) from the cyclocondensation reaction of trichloromethyl-substituted 1,3-dielectrophiles (1a–f) with dry hydrazine and N-methylhydroxylamine is reported. The regiospecific cyclocondensation took place with the elimination of the trichloromethyl group in a haloform type reaction when acetonitrile under basic medium was used. The structure of compounds 2
的一个新系列hydroxypyrazoles(合成2A - ˚F(和2-甲基-3- isoxazolones)3A - d从三
氯甲基取代的1,3- dielectrophiles的环化缩合反应)(1A - ˚F)与干燥的
肼和ñ -报道了甲基
羟胺。当在碱性介质下使用
乙腈时,区域特异性的环缩合反应在卤仿型反应中消除了三
氯甲基。化合物2和3的结构主要由1 H和13 C NMR光谱确定。