6-(3-氨基苯基)-4,5-二氢哒嗪-3(2H)-酮的合成

Synthesis of 6-( 3-Aminophenyl)-4,5-dihydropyridazin-3( 2H)-one

以苯、丁二酸酐为原料,经傅克酰基化,硝化,与水合肼反应三步反应合成6-(3-氨基苯基)-4,5-二氢哒嗪-3(2H)-酮(1),总收率为58.3%。由3-(3-硝基苯甲酰基)丙酸(3)合成化合物1的过程中,在雷尼镍(Raney Ni)的催化下与水合肼反应,一步完成了苯环上硝基的还原和成环。重点考察了该步反应的物料配比、反应时间对产率的影响。结果表明,水合肼与化合物3的摩尔比11.7∶1,回流反应4 h,产率为82.7%。

6- （3-Aminophenyl） -4,5-dihydropyridazin-3 （2H） -one （ 1 ） has been synthesized by using benzene and succinic anhydride as starting materials via a three-step process including Friedel-Crafts acylation, nitration, reduction with hydrazine hydrate in an overall yield of 58.3%. Under catalysis of Raney Ni, β-mnitrobenzoylpropionic acid （3） reacted with hydrazine hydrate to give compound 1 by one step of nitro reduction and ring closing. The effects of the amount of hydrazine and reaction time on the yield of above reaction have been explored. When the reaction was refluxed for 4 h with molar ratio of hydrazine to compound 3 at 11.7：1, the yield of compound 1 was up to 82. 7% .