Hydrolysis of BNPP catalyzed by the crowned Schiff base Co(II) complexes in micellar solution

摘要

Two symmetrical double aza-crowned Schiff base cobalt(II) complexes were synthesized and characterized, and the metallomicelle made up of the cobalt(II) complexes and surfactant, as mimic hydrolytic metalloenzyme, was used in catalytic hydrolysis of bis(4-nitrophenyl) phosphate (BNPP). The analysis of specific absorption spectrums of the hydrolytic reaction systems indicated that key intermediates made up of BNPP and Co(II) complexes are formed in reaction processes of the BNPP catalytic hydrolysis. In this article, the mechanism of BNPP catalytic hydrolysis has been proposed based on the analytic result of specific absorption spectrum. A kinetic mathematical model, for the calculation of the kinetic parameter of BNPP catalytic hydrolysis has been established based on the mechanism proposed. The acid effect of reaction system, the structural effect of the complexes, the effect of surfactant micelles and the effect of temperature on the rate of BNPP hydrolysis catalyzed by the complexes have been discussed.