Hydrolysis of p-Nitrophenyl Picolinate Catalyzed by Mono-Schiff Base Complexes with Aza-crown Ether or Morpholino Pendants

作者：Li Jianzhang; Jiang Weidong; Feng Famei; Xu Bin; Hu Wei; Zhang Jin; Qin Shengying

来源：Chinese Journal of Chemistry, 2009, 27(2): 372-378.

DOI：10.1002/cjoc.200990061

• benzo-10-aza-crown ether
• mono-Schiff base complex
• mimic hydrolase
• catalytic kinetics
• p-nitrophenyl picolinate

Mono-Schiff base cobalt(II) and manganese(III) complexes with either benzo-10-aza-crown ether pendants (CoL(2)(1), MnL(2)(1)Cl) or morpholino pendants (CoL(2)(2), MnL(2)(2)Cl) have been employed as models for hydrolase enzymes by studying the kinetics of their hydrolysis reactions with p-nitrophenyl picolinate (PNPP). The kinetic mathematical model of PNPP cleavage catalyzed by these complexes was proposed. The effects of complex structures and reaction temperature on the rate of catalytic PNPP hydrolysis have been also examined. The results showed that the rate increases with pH of the buffer solution and four complexes exhibited high activity in the catalytic PNPP hydrolysis. Compared with the crown-free analogy CoL(2)(2) and MnL(2)(2)Cl, the crowned Schiff base complexes (CoL(2)(1), MnL(2)(1)Cl) exhibit higher catalytic activity. The pseudo-first-order-rate (k(obs)) for the PNPP hydrolysis catalyzed by the complex MnL(2)(1)Cl containing benzo-10-aza-crown ether is 923-fold higher than that of hydrolysis of PNPP at pH=7.00, 25 degrees C,[S]=2.0 X 10(-4) mol center dot dm(-3).

• 出版日期2009-2
• 单位四川轻化工大学; 重庆文理学院