Non-heme iron(III) complex with tridentate ligand: Synthesis, structures and catalytic oxidations of alkanes

We report synthesis and characterization of a mononuclear iron(III) complex [Fe(LH2)Cl2]+, 1 having tridentate ligand LH2 and their application in oxidation of alkanes. Complex, 1 was characterized by various analytical, spectroscopic, electrochemical, crystallographic and theoretical studies. The molecular structure determination showed the presence of distorted square pyramidal FeN3Cl2 coordination sphere. Selective oxidation of benzyl alcohol, fluorene, adamantane, 1-phenyl ethanol and n-octane in presence of catalytic amount [FeIII(LH2)Cl2]+ with H2O2 under mild conditions give products in good to excellent yields through FeIVO intermediate. Several studies were done to support the reactive intermediate. Generation of FeIVO intermediate was also supported by UV-visible titration of [FeIII(LH2)Cl2]+ and H2O2 at low temperature and their visual colour change from red (500 nm, ɛ = 1050 M− 1 cm− 1) to green (770 nm, ɛ = 153 M− 1 cm− 1).