离子液体催化制备3,5-二叔丁基-4-羟基苯甲酸正十六酯

Synthesis of hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate using acidic ionic liquid as catalyst

制备了四种酸功能离子液体,用IR和~1HNMR对其结构进行表征,并用于催化合成3,5-二叔丁基-4-羟基苯甲酸正十六酯的反应研究。考察了反应条件和催化剂重复使用情况。结果表明,当离子液体[HS0_3-pmim]^+[HS0_4]^-用量为3,5-二叔丁基-4-羟基苯甲酸质量的7.5%,n(酸)∶n(醇)=1∶1.1时,反应温度120℃,反应5.5h,酯化率可达98.5%,选择性为92.5%。反应后离子液体分离后重复使用5次,仍有较高的催化活性。

Four acidic functionalized ionic liquids were synthesized and their structure were confirmed by IR and ^1 HNMR. In the presence of these ionic liquids as catalyst,the reaction of synthesizing hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate was studied.The results showed under the conditions of[HS03-pmim]^＋[HS04]^-dosage 7. 5%in the weight of 3,5-di-tert-butyl-4-hydroxybenzoic acid,with n（ 3,5-di-tert-butyl-4-hydroxybenzoic acid） ∶ n（ 1-hexadecanol） = 1 ∶ 1. 1,temperature 120℃ and time 5. 5 h,conversion rate was up to 98%,the yield reached 92. 5%. After reaction,the ionic liquid were separated and was reused 5 times,it still remained a highercatalytic activity.