Reactivity of Dinuclear Copper(II) Complexes with N‐Salicylidene Glycine Schiff Bases as Carboxylesterase Models

Abstract

Two phenoxo-bridged dinuclear copper(II) complexes (Cu 2 L 1 2 , Cu 2 L 2 2 ) with Nsalicylidene glycine Schiff bases were prepared and evaluated their performance for catalyzing the hydrolysis of p-nitrophenyl picolinate (PNPP). The observations reveal that the as-prepared dinuclear copper(II) complexes exhibited better activity by two to three orders of magnitude rate enhancement in comparison with the autohydrolysis rate of PNPP. Chloro-containing Cu 2 L 2 2 aroused approximately three times kinetic advantage over chloro-free Cu 2 L 1 2 at pH 7.0, which is probably contributed to the electron-withdrawing inductive effect of the 5 -chloride group. Moreover, it was found that the pH-responded kinetic behavior displayed an enzyme-like property for the PNPP hydrolysis by the two complexes.