A simple and efficient methodology for highly regioselective synthesis of azomethine pyrazoles and isoxazoles containing a trifluoromethyl group is reported. The cyclocondensation of trifluoromethylated β-enamino diketones (TBED) with phenylhydrazine and hydroxylamine hydrochloride, in the presence of BF₃, provided 5-aryl-4-[(tert-butyl)iminomethyl]-3-trifluoromethylazoles by aza-Michael-type 1,2-addition. The scope of the reaction was expanded by transimination with arylamines in a one-pot method starting from TBED. Thus, 83 novel 4-[(alkyl/aryl)iminomethyl]-3-trifluoromethylazoles were obtained with high regioselectivity and in yields of 51 to 89%.

中文翻译：

---

1,2-三氟甲基化的β-烯氨基二酮的加成：区域选择性合成含三氟甲基的偶氮甲碱吡唑和异恶唑

报道了一种简单有效的方法，用于高度区域选择性合成含三氟甲基的甲亚胺吡唑和异恶唑。在BF ₃的存在下，三氟甲基化的β-烯氨基二酮（TBED）与苯肼和盐酸羟胺的环缩合，通过aza-Michael型1提供了5-芳基-4-[（叔丁基）亚氨基甲基] -3-三氟甲基唑。 ，2-加法。从TBED开始，通过一锅法通过芳基胺的氨基转移来扩大反应范围。因此，获得了83种具有高区域选择性且产率为51-89％的新颖的4-[（（烷基/芳基）亚氨基甲基] -3-三氟甲基唑）。