Brij35胶束溶液中大环Schiff碱配合物催化羧酸酯水解的动力学研究  

Catalytic Hydrolysis of Carboxylic Acid Esters by Complexes Containing a Tetracoordinate Macrocyclic Schiff Base Ligand in Brij35 Micellar Solution

作　　者：韦一良[1] 覃治中 程四清[1] 

机构地区：[1]武汉工业学院生化系,武汉430023 [2]深圳盐田港供水有限公司,广东深圳518000

出　　处：《四川大学学报（自然科学版）》2004年第5期1030-1035,共6页Journal of Sichuan University(Natural Science Edition)

基　　金：湖北省教育厅基金资助

摘　　要：作者研究了30℃时,Brij35胶束溶液中大环Schiff碱的Cu(Ⅱ)和Zn(Ⅱ)配合物催化PNPP和PNPA水解反应的动力学,结果表明,两种配合物催化PNPP和PNPA水解反应的机理是不同的.Cu(Ⅱ)配合物仅催化PNPP的水解,其机理是外部氢氧根离子对羰基的亲核进攻,而Zn(Ⅱ)配合物能同时加速PNPP和PNPA的水解,其机理为锌键合的氢氧根离子对PNPP羰基的分子内亲核进攻和锌键合的氢氧根离子对PNPA羰基的分子间亲核进攻.Zn(Ⅱ)配合物的催化活性高于Cu(Ⅱ)配合物.The macrocyclic Schiff base complexes of Cu(Ⅱ) and Zn(Ⅱ) in Brij35 micellar solution are investigated kinetically for the catalytic hydrolysis of p-nitrophenyl acetate (PNPA) and p-nitrophenyl picolinate (PNPP) at 30℃. The results indicate that different mechanisms are operative for the two complexes in the hydrolysis of PNPA and PNPP. The Cu(Ⅱ) complex can only catalyze the hydrolysis of PNPP by the mechanism which involves the nucleophilic attack of external hydroxide ion on the carbonyl, while the Zn(Ⅱ) complex can accelerate the hydrolysis of both PNPP and PNPA , by way of the intramolecular nucleophilic attack of zinc-bound hydroxide ion on carbonyl for PNPP and the intermolecular nucleophilic attack of zinc-bound hydroxide ion on carbonyl for PNPA, respectively. The catalytic activity of Zn(Ⅱ) complex is higher than that of Cu(Ⅱ) complex.

关 键 词：大环Schiff碱配合物 羧酸酯水解 金属胶束催化 动力学 

分 类 号：O643[理学—物理化学]