The cyclocondensation of 3,4-substituted 5-aminopyrazoles with unsymmetrical 1,3-dicarbonyl compounds containing the difluoromethyl group in acetic acid led to 7-difluoromethylpyrazolo[1,5-a]pyrimidines, whereas 5-difluoromethylpyrazolo[1,5-a]pyrimidine derivatives were predominantly formed in trifluoroacetic acid.

中文翻译：

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5-二氟甲基和7-二氟甲基取代的吡唑并[1,5-a]嘧啶的区域选择性合成

3,4-取代的5-氨基吡唑与含有二氟甲基的不对称1,3-二羰基化合物在乙酸中环缩合生成7-二氟甲基吡唑并[1,5- a ]嘧啶，而5-二氟甲基吡唑并[1,5- a] ]嘧啶衍生物主要在三氟乙酸中形成。