Hetero-Diels-Alder reactions of N-phosphoryltrihaloacetimidoyl chlorides with 1,3-butadienes
作者:Mykola V. Kolotylo、Oleksii A. Synytsya、Petro P. Onys’ko
DOI:10.3998/ark.5550190.0013.410
日期:——
Hetero-Diels-Alder reactions of N-phosphoryltrihaloacetimidoyl chlorides with 1,3-butadienes led to new 2-chloro-2-trihalomethyl substituted tetrahydropyridine adducts. Cycloadducts with CF3 group undergo thermal or acid catalyzed dehydrochlorination affording respective dihydropyridines and subsequent aromatization to form 2-trifluoromethylpyridines. Trichloromethyl analogs under similar conditions
N-磷酰基三卤代乙酰亚氨基酰氯与 1,3-丁二烯的杂-Diels-Alder 反应导致新的 2-氯-2-三卤甲基取代的四氢吡啶加合物。具有 CF3 基团的环负载物经过热或酸催化脱氯化氢,得到相应的二氢吡啶,随后芳构化形成 2-三氟甲基吡啶。三氯甲基类似物在类似条件下经历芳构化,伴随着 CCl3 基团的异常还原,形成各自的 2-二氯甲基取代的吡啶。