A DIMERIC IRON(III)-SCHIFF BASE COMPLEX AS A FUNCTIONAL MODEL FOR PHENOXAZINONE SYNTHASE

摘要

A new dimeric iron(III) complex, [Fe(L)Cl]_2 (1) containing a (N,0)-donor Schiff base ligand (H_2L = 2-((2-hydroxyphenylimino)methyl)-6-methoxyphenol, has been synthesized and structurally characterized by different spectroscopic methods. The composition of iron(III)-Schiff base complex has been determined by plotting of ligand to metal mole ratio against absorbance. The silent nature of the electron paramagnetic resonance (EPR) spectrum at room temperature reveals that existence of possible antiferromagnetic interaction between two iron(III) centres which are coupled via phenoxo bridges of the Schiff base ligands. The diiron complex has been evaluated to mimics phenoxazinone synthase enzyme and significantly promotes the oxidative coupling of 2-aminophenol (AP) to 2-aminophenoxazin-3-one in acetonitrile medium under aerobic condition with turn over number, k_(cat) =1.20x10~4 h~(-1).