Metallomicelles made of dinuclear copper(II) complexes of oxamido-bridge as symmetric two-center catalysts of the cleavage of carboxylic acid esters

The syntheses of the dinuclear copper(II) complexes 1 and 2 of oxamido-bridge were reported. Reaction kinetics and the mechanism on hydrolysis of p-nitrophenyl picolinate (PNPP) and p-nitrophenyl acetate (PNPA) catalyzed by the metallomicelles formed from the complex (1 or 2) and surfactants (N-lauroyl sarcosinate (LSS), polyoxyethylene (23) lauryl ether (Brij35), cetyl pyridinium bromide (CPB)) were investigated. The kinetic mathematical models for the catalytic hydrolysis of PNPP and PNPA were proposed, respectively. The effects of different micelles and the structure of the ligands on the catalytic hydrolysis of PNPP and PNPA were discussed in detail. The results showed that the rate enhancement of the catalytic hydrolysis of PNPP following the intramolecular reaction is bigger than that of PNPA following the intermolecular reaction in the same experimental conditions, and the metallomicelle containing oxamido-bridged dinuclear copper(II) complex may be a potential catalyst for the hydrolysis of PNPP and PNPA.