Solvent and catalyst free azo-Michael addition under high-speed vibration milling

Under the high-speed vibration milling conditions,the solvent and catalyst-free azo-Michael addition of chalcone derivatives and amines was found to proceed efficiently in excellent yields at ambient temperature in short reaction time.In most cases,conventional side reactions were avoided and thus quantitative yields were achieved.The influences of the vibration frequency and reaction time on the azo-Michael addition were investigated.

亚硫酸盐对偶氮染料橙黄Ⅱ的脱色效能及机理研究

利用亚硫酸盐对典型偶氮染料--橙黄Ⅱ(AO7)进行脱色,发现亚硫酸盐浓度升高有助于AO7的快速去除,在90 min内降解率达到95%以上。通入空气会造成部分SO^2-3被氧化,降低了AO7的降解率。温度升高和中性p H值条件有利于AO7的降解;高浓度亚硫酸盐条件下AO7初始浓度对其降解影响不大,低浓度亚硫酸盐对AO7的降解率则随AO7初始浓度的升高而降低。亚硫酸盐是一种亲核试剂,它对AO7的脱色是迈克尔加成的结果,并且在亚硫酸盐过量时能达到不可逆的脱色效果。