Selective oxidation of benzyl alcohol to benzaldehyde, 1-phenylethanol to acetophenone and fluorene to fluorenol catalysed by iron (II) complexes supported by pincer-type ligands: Studies on rapid degradation of organic dyes

摘要

Hexacoordinated non-heme iron complexes [Fe-II(L-1)(2)](ClO4)(2) (1) and [Fe-II(L-2)(2)](PF6)(2) (2) have been synthesized using ligands L-1 = (E)-2-chloro-6-(2-(pyridin-2ylmethylene) hydrazinyl)pyridine and L-2 = (E)-2-chloro-6-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl) pyridine]. These complexes are highly active non-heme iron catalysts to catalyze the C (sp(3))-H bonds of alkanes. These iron complexes have been characterized using ESI-MS analysis and molecular structures were determined by X-ray crystallography. ESI - MS analysis also helped to understand the generation of intermediate species like Fe-III-OOH and Fe-IV=O. DFT and TD-DFT calculations revealed that the oxidation reactions were performed through high-valent iron center and a probable reaction mechanism was proposed. These complexes were also utilized for the degradation of orange II and methylene blue dyes.