Pyrazole bridged dinuclear Cu(II) and Zn(II) complexes as phosphatase models: Synthesis and activity

作者：Naik Krishna; Nevrekar Anupama; Kokare Dhoolesh Gangaram; Kotian Avinash; Kamat Vinayak; Revankar Vidyanand K^*

来源：Journal of Molecular Structure, 2016, 1125: 671-679.

DOI：10.1016/j.molstruc.2016.07.036

• Phosphatase-like activity
• Lewis acid activation
• DFT
• Schiff base
• Pyrazole-3,5-dicarbohydrazide
• Dinuclear complex

Present work describes synthesis of dibridged dinuclear [Cu2L2(mu(2)-NN pyr)(NO3)(2)(H2O)(2)] and [Zn2L(mu-OH)(mu-NNpyr)(H2O)(2)] complexes derived from a pyrazole based ligand bis(2-hydroxy-3-methoxybenzylidene)-1H-pyrazole-3,5-dicarbohydrazide. The ligand shows dimeric chelate behaviour towards copper against monomeric for zinc counterpart. Spectroscopic evidences affirm octahedral environment around the metal ions in solution state and non-electrolytic nature of the complexes. Both the complexes are active catalysts towards phosphomonoester hydrolysis with first order k(cat) values in the range of 2 x 10(-3)s(-1). Zinc complex exhibited promising catalytic efficiency for the hydrolysis. The dinuclear complexes hydrolyse via Lewis acid activation, whereby the phosphate esters are preferentially bound in a bidentate bridging fashion and subsequent nucleophilic attack to release phosphate group.

• 出版日期2016-12-5