表面活性剂型过氧钨酸盐催化合成己二酸

Synthesis of Adipic Acid Catalyzed by Surfactant-type Peroxotungstate

对清洁合成己二酸反应中的钨酸盐催化剂进行了改性,制备了一种含长碳链的亲油性钨过氧酸盐双功能催化剂[C7H7C12H25(CH3)2N]2W2O3(O2)4,通过元素分析、重量法、化学滴定、TG-DSC和IR光谱对催化剂的组成和结构进行了表征。与已报道的钨酸盐类催化体系相比,该配合物在温和的、不需助催化剂的条件下,能有效地催化w(H2O2)=30%双氧水氧化环己烯、环己醇、环己酮和1,2-环己二醇生成己二酸。以环己烯作底物,讨论了催化剂用量、反应温度、时间、H2O2用量4个因素对反应的影响,得到的较佳合成条件(以100 mmol环己烯计)为:反应温度90℃,反应时间12 h,n(环己烯)∶n(催化剂)∶n(H2O2)=100∶1.2∶538,己二酸收率可达85.8%。同样条件下,催化剂对1,2-环己二醇、环己醇和环己酮的活性分别为88.5%、58.3%和52.0%。

A novel bifunctional amphiphilic quaternary ammonium isopolyperoxotungstate [ C7H7CI2H25 （CH3） 2N ] 2W2O3 （O2）4 was synthesized for use as catalyst in clean synthesis of adipic acid. It was characterized by elementary analysis, gravimetry, chemical titration, TG - DSC and IR spectroscopy. Compared with the reported catalytic systems of tungstate, for oxidation of cyclohexene, cyclohexanol, cyclohexanone and 1,2-cyclohexanediol with 30% H2O2 to adipic acid, the catalytic activity of this compound was high under moderate reaction conditions without co-catalyst. Thus, the yield of adipic acid could reach 85.8% with n（cyclohexene） ：n（catalyst） ：n（ H2O2 ） = 100：1.2：538 reacting at 90 ℃ for 12 h. Under the same conditions, the yields from 1, 2-cyclohexanediol, cyclohexanone and cyclohexanol were 88.5% ,58.3% and 52.0% respectively.