Catalytic Oxidation of Alkanes and Alkenes by H2O2 with a mu-Oxido Diiron(III) Complex as Catalyst/Catalyst Precursor

Summary, in English

A new mu-oxo diiron(III) complex of the lithium salt of the pyridine-based unsymmetrical ligand 3-[(3-{[bis(pyridin-2-ylmethyl)amino]methyl}-2-hydroxy-5-methylbenzyl)(pyridin2-ylmethyl)amino] propanoate (LiDPCPMPP), [Fe-2(mu-O)(LiDPCPMPP)(2)](ClO4)(2), has been synthesized and characterized. The ability of the complex to catalyze oxidation of several alkanes and alkenes has been investigated by using CH3COOH/H2O2 (1:1) as an oxidative system. Moderate activity in cyclohexane oxidation (TOF = 33 h(-1)) and good activity in cyclohexene oxidation (TOF = 72 h(-1)) were detected. Partial retention of configuration (RC = 53%) in cis- and trans-1,2-dimethylcyclohexane oxidation, moderate 3 degrees/2 degrees selectivity (4.1) in adamantane oxidation, and the observation of a relatively high kinetic isotope effect for cyclohexane oxidation (KIE = 3.27) suggest partial metal-based oxidation, probably in tandem with free-radical oxidation. Low-temperature UV/Vis spectroscopy and mass spectrometric studies in the rapid positive detection mode indicate the formation of a transient peroxido species, [Fe-2(O)(O-2)-(LiDPCPMPP)(2)](2+), which might be an intermediate in the metal-based component of the oxidation process.

• Author: Biswanath Das; Afnan Al-Hunaiti; Matti Haukka; Serhiy Demeshko; Steffen Meyer; Albert A. Shteinman; Franc Meyer; Timo Repo; Ebbe Nordlander
• Department/s: Chemical Physics
• Publishing year: 2015
• Language: English
• Pages: 3590-3601
• Publication/Series: European Journal of Inorganic Chemistry
• Issue: 21
• Links: http://dx.doi.org/10.1002/ejic.201500576
• Document type: Journal article
• Publisher: John Wiley & Sons Inc.
• Topic: Inorganic Chemistry
• Keywords: Monooxygenases; Iron; Lithium; Oxidation; Homogeneous catalysis
• Status: Published
• ISBN/ISSN/Other: ISSN: 1099-0682