syntheses, characterization and study of the use of cobalt (ii) schiff–base complexes as catalysts for the oxidation of styrene by molecular oxygen的合成、表征和研究使用钴(ii)席夫碱配合物作为催化剂的氧化苯乙烯分子氧.pdf

Molecules 2005, 10, 302-311 molecules ISSN 1420-3049 Syntheses, Characterization and Study of the Use of Cobalt (II) Schiff–Base Complexes as Catalysts for the Oxidation of Styrene by Molecular Oxygen Ali Akbar Khandar 1, Kamellia Nejati 2,* and Zolfaghar Rezvani 3 1 Department of Inorganic Chemistry, Faculty of Chemistry, Tabriz University, Tabriz, Iran 2 Payam Noor University -Tabriz Center, Emamieh ,Hakimnezami Street, Tabriz, Iran 3 Department of Chemistry, Faculty of Science, Azarbaijan University of Tarbiat Moallem, Tabriz, Iran * Author to whom correspondence should be addressed: Fax: (+98) 411 5412108; Tel: (+98) 411 5412117; e-mail: nejati_k@. Received: 13 August 2004 / Accepted: 14 September 2004 / Published: 31 January 2005 Abstract: Schiff-Base complexes of bis-5-phenylazosalicylaldehyde ethylenediimine and bis-5-phenylazosalicylaldehyde-O-phenylenediimine ligands with Co(II) (I and II) have been synthesized and characterized by their IR spectra and elemental analyses. These complexes catalyze the oxidation of styrene in the presence of dioxygen and excess pyridine. The effect of the reaction conditions on the oxidation of styrene was studied by varying solvent, nature and amount of the catalyst and substrate. The catalytic behavior of the studied complexes was shown to be dependent on the conditions applied. In all reactions, acetophenone and 1- phenylethanol were the only observed products. Keywords: Cobalt, Schiff base complexes, Salicylidene, Styrene, Oxidation