Abstract
Herein, new substituted ligands based on pyrazole (L-1-L-4) were synthesized via a one-step by condensing (1H-pyrazole-1-yl) methanol with different primary amine compounds. The present work utilized the catalytic properties of the in situ complexes formed by these ligands with various copper (II) salts viz. Cu(CH3COO)(2), CuSO4, CuCl2, and Cu(NO3)(2) for the oxidation of catechol to o-quinone. The studies showed that the catalytic activities depend on the nature and concentration of the ligand, the nature of the counterion, and the solvent. It was observed that the complex formed by L-2 and Cu(CH3COO)(2) exhibited good catalytic activity in methanol with V-max of 41.67 mu mol L-1 min(-1) and K-m of 0.02 mol L-1.