Non-Condensed Trifluoromethylated 5,5-Bicycles: Synthesis of 2-[3-Alkyl(phenyl)-1H-pyrazol-1-yl]-4-phenyl-5-alkylthiazole and -4,5,6,7-tetrahydrobenzothiazole Systems
作者:Helio Gauze Bonacorso、Arci Dirceu Wastowski、Mauro Neves Muniz、Nilo Zanatta、Marcos Antonio Pinto Martins
DOI:10.1055/s-2002-31955
日期:——
A convenient method for the synthesis of a novel series of eighteen non-condensed 5,5-bicycles, specifically 2-[3-alkyl(phenyl)-5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-pyrazol-1-yl]-4-phenyl-5-alkylthiazoles and -4,5,6,7-tetrahydrobenzothiazoles 3a-i from the reaction of 3-alkyl(phenyl)-5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-pyrazolethiocarboxyamide (1) with 2-bromoacetophenone, 2-bromopropiophenone and 2-bromocyclohexanone (2), is reported. The dehydration of compounds 3a-i with a mixture of concentrated sulfuric acid-acetic acid (1:10 v/v) led to the corresponding 2-[3-alky(phenyl)-5-trifluoromethyl-1H-pyrazol-1-yl]-4-phenyl-5-alkylthiazoles and respective 4,5,6,7-tetrahydrobenzothiazoles 4a-i in good yield.
一种合成十八种非缩合 5,5-双环新系列的简便方法,特别是 2-[3-烷基(苯基)-5-羟基-5-三氟甲基-4,5-二氢-1H-吡唑-1-基]-4-苯基-5-烷基噻唑和-4,5,6、报告了 3-烷基(苯基)-5-羟基-5-三氟甲基-4,5-二氢-1H-1-吡唑硫代羧酰胺 (1) 与 2-溴苯乙酮、2-溴苯丙酮和 2-溴环己酮 (2) 反应生成的 4,5,6,7-四氢苯并噻唑 3a-i。用浓硫酸-乙酸(1:10 v/v)的混合物对化合物 3a-i 进行脱水,得到了相应的 2-[3-烷基(苯基)-5-三氟甲基-1H-吡唑-1-基]-4-苯基-5-烷基噻唑和各自的 4,5,6,7-四氢苯并噻唑 4a-i,收率良好。