Synthesis, structure, luminescent properties and catecholase activity of Zn(II) complex with N, O chelating agent

Abstract

A mononuclear tetrahedral Zn(II) complex [Zn(L)2](1)[HL = 2-(benzylimino)methyl)phenol] with phenol based bi-dentate N,O donor ligand have been prepared. The compound is characterized by various spectroscopic tools and the structure of the complex is solved by single crystal X-ray diffractometer. The tetrahedral Zn(II) complex crystallized in monoclinic space group I2/awith a = 12.2908(3) (Å), b = 9.1041(2) (Å), c = 19.9812(7) and β = 96.1466(10)°.Cyclic voltametric study of the complex 1 gives an irreversible oxidation peak due to ligand based oxidation of the phenol moiety to the phenoxyl radical. This compound also shows a strong emission band at 455 nm. The reported Zn(II) complex exhibits catecholase activity in methanol solvent under aerobic condition.The Kcatvalue for 1 in methanol is 8.411 × 103 h−1. The conversion of 3,5-di-tert-butyl catechol (3,5 DTBC) to 3,5-di-tert-butyl quinone (3,5 DTBQ) is catalysed by mono nuclear Zn(II) complex and the reaction proceeds through the generation of ligand centered phenoxyl radical.