锌-丙酸铵还原体系用于氢化偶氮苯的合成

摘要

Hydrazobenzene was prepared by magnesium powder） ＇saturated solution of azobenzene with metal powder （zinc powder and ammonium salt （ammonium oxalate, ammonium propionate and ammonium benzoate） as reductant. Zinc-ammonium propionate was selected as the best reduction system according to reaction time and the result. The effects of molar ratio of azobenzene to zinc powder and the amount of saturated solution of ammonium propionate on the yields of hydrazobenzene were investigated at 25℃. The optimum conditions showed that the molar ratio of azobenzene to zinc powder is 1 ： 2.0 （the amount of azobenzene is 1.25 mmol）, the consumption of saturated solution of ammonium propionate is 2.5 mL, the average yield of hydrazobenzene is 90.1% and the reaction time is 3.2 min. The synthesized compound was verified to be hydrazobenzene by the melting point and infrared spectra.%选用锌粉和镁粉与不同饱和铵盐（草酸铵、丙酸铵和苯甲酸铵）水溶液组成还原体系，由偶氮苯制备氢化偶氮苯，根据反应时间及结果选取锌一饱和丙酸铵水溶液为最佳还原体系。在反应温度25℃时，研究了锌一饱和丙酸铵水溶液还原体系还原偶氮苯反应，考察了偶氮苯与锌粉物质的量比、饱和丙酸铵水溶液的用量对氢化偶氮苯收率的影响。实验结果表明：偶氮苯与锌粉物质的量比1：2．0（偶氮苯1．25mmol），饱和丙酸铵溶液的用量2．5mL为最佳反应条件，平均收率为90．1％，反应时间约3．2min。产品进行熔点测定及红外光谱分析，结果与文献一致。