摘要
报道了以环己烷/水为溶剂,四丁基溴化铵为相转移催化剂,催化二氧化硫脲还原偶氮染料2硝基4氯2′羟基3′叔丁基5′甲基偶氮苯合成紫外线吸收剂UV326。在优化反应条件下,即反应物物质的量的比为n偶氮染料∶n二氧化硫脲∶n四丁基溴化铵∶n氢氧化钠=1∶3.2∶0.06∶11时,70mL环己烷、70mL水,在72℃反应0.5h,收率可达98.4%,产品经HPLC分析,UV326含量为99.8%。探讨了不同反应条件对反应的影响。用该方法合成的UV326具有优良的紫外吸收能力,且在500nm处的透光率达99%以上。
In this paper, direct reduction of 2-nitro-4-chloro-2＇- hydroxy-3＇-t-butyl-5＇-methyl-azobenzene to form ultraviolet absorbent UV-326 with thiourea dioxide in the presence of the mixed solvent cyclohexane/water and a phase transfer catalyst Bu4NBr was reported. Under the optimal conditions： azo dye： thiourea dioxide ： Bu4NBr ： NaOH = 1 ： 3.2 ： 0.06 ： 11 （ molar ratio,8.63mmol of azo dye）,70mL cyclohexane and 70mL water were heated at 72℃ for 0.5h to give UV-326 in 98.4% yield and 99.8% purity （by HPLC）. The product prepared by this method had strong absorption of ultraviolet light and 99.9% transmittance at the wavelength of 500nm.
出处
《化学试剂》
CAS
CSCD
北大核心
2006年第7期388-390,438,共4页
Chemical Reagents
关键词
紫外线吸收剂
相转移催化
二氧化硫脲
还原
透光率
ultraviolet absorbent
phase transfer catalysis
thiourea dioxide
reduction
transmitance
