Synthesis of new 1-[4-methane(amino)sulfonylphenyl)]-5-[4-(aminophenyl)]-3-trifluoromethyl-1<i>H</i>-pyrazoles
作者:Khaled R. A. Abdellatif、Morshed A. Chowdhury、Edward E. Knaus
DOI:10.1002/jhet.5570450623
日期:2008.11
A regiospecific cyclization-dehydration reaction of a 1-[(4-(N-alkyl-N-(tert-butyloxycarbony)amino)-phenyl]-4,4,4-trifluorobutane-1,3-done with a 4-aminosulfonyl-, or 4-methylsulfonyl-, phenylhydrazine hydrochloride in refluxing ethanol proceeded with simultaneous loss of the N-tert-butyloxycarbonyl protecting group to afford a group of 1-(4-methanesulfonylphenyl or 4-aminosulfonylphenyl)-5-[4-(N-
1-[(4-(N-烷基-N-(叔丁氧基羰基)氨基)-苯基] -4,4,4-三氟丁烷-1,3-done与4-氨基磺酰基的区域特异性环化-脱水反应-或4-甲基磺酰基-苯肼盐酸盐在回流的乙醇中进行,同时失去N-叔丁氧基羰基保护基,得到1-(4-甲磺酰基苯基或4-氨基磺酰基苯基)-5- [4-(N -alkylaminophenyl)] - 3-(三氟甲基)-11 ħ。-pyrazoles(6)随后的吡唑6(的反应- [R 1 = R 2 =具有进行一氧化氮(40 psi)的Me)中经由一个ñ -methylamino- ñ-diazen -1-鎓-1,2-二醇盐中间体,其更基本的二氮烯-1-鎓-1,2-二醇盐的发生质子Ñ 2 -氮,然后硝酰基(HNO)的损失种类,得到的Ñ -亚硝基产物7。