离子液体中3,4-二羟基苯甲醛的简便合成  

Facile Synthesis of 3,4-Dihydroxybenzaldehyde in Ionic Liquid

作　　者：刘长春[1] 卢卫平[1] 金德宽[1] 

机构地区：[1]江苏食品职业技术学院生物化工系,江苏淮安223003

出　　处：《高校化学工程学报》2011年第4期724-728,共5页Journal of Chemical Engineering of Chinese Universities

摘　　要：研究了对羟基苯甲醛在离子液体中经溴化、水解一锅法合成3,4-二羟基苯甲醛的简便方法。对羟基苯甲醛首先与离子液体[bmim]Br3进行溴化反应得到3-溴-4-羟基苯甲醛,在对羟基苯甲醛与[bmim]Br3物质的量比1:1,20℃,30 min和无溶剂条件下,单溴化产物的选择性为99.7%。溴化反应产物不经分离,直接在离子液体[bmim]Br中与氢氧化钠溶液发生水解反应得到3,4-二羟基苯甲醛,在氢氧化钠用量1.25 mol.(mol对羟基苯甲醛)-1,100℃和2 h条件下,产率84.7%,纯度99.3%。离子液体重复使用6次,3,4-二羟基苯甲醛的产率和纯度无明显降低。该方法简便易行,反应条件温和,产率高,选择性好,不使用有机溶剂,对环境友好。A facile one-pot method for synthesis of 3,4-dihydroxybenzaldehyde from p-hydroxybenzaldehyde via bromination and hydrolysis in ionic liquid was studied.Under the conditions of the molar ratio of p-hydroxybenzaldehyde to ionic liquid 1-butyl-3-methylimidazolium tribromide（Br3） 1：1,reaction temperature 20℃,reaction time 30 min and solvent-free,the p-hydroxybenzaldehyde was brominated with ionic liquid Br3 to give 3-bramo-4-hydroxybenzaldehyde with 99.7% selectivity;and then without separation,the product of bromination was further hydrolyzed with NaOH aqueous solution in ionic liquid 1-butyl-3-methylimidazolium bromide（Br）,which is formed from Br3 after the process of bromination,to form 3,4-dihydroxybenzaldehyde with 84.7% yield and 99.3% purity under the conditions as follows： the NaOH dosage is 1.25 mol·（mol p-hydroxybenzaldehyde）-1,reaction temperature is 100℃ and reaction time is 2 h.The ionic liquid can be reused at least six times without significant decrease of the yield and purity of 3,4-dihydroxybenzaldehyde.This method has the advantages of convenience,mild reaction conditions,good yield,high selectivity,solvent-free and environmental friendliness.

关 键 词：3 4-二羟基苯甲醛 对羟基苯甲醛 离子液体 [bmim]Br3 

分 类 号：O625.41[理学—有机化学] TQ244.1[理学—化学]