Polystyrene-bound imidazole as a heterogeneous axial ligand for Mn(salophen)Cl and its use as biomimetic alkene epoxidation and alkane hydroxylation catalyst with sodium periodate

In the present work, an account of biomimetic oxidation, Mn(III) salophen has been successfully bonded to imidazole modified polystyrene. Polystyrene-bound imidazole, (PSI), is not only a heterogeneous axial base but also is a support for immobilization of Mn(III) salophen. Mn(salophen)Cl-PSI catalyze alkene epoxidation with sodium periodate under agitation with magnetic stirring. Alkyl aromatic and cycloalkanes were oxidized efficiently to their corresponding alcohols and ketones in the presence of this catalyst. This new heterogenized catalyst is of high stability and reusability in the oxidation reactions. This heterogenized system showed the higher selectivity and stability in comparison with the homogeneous system, Mn(salophen)Cl. The catalyst, Mn(salophen)Cl-PSI, has been characterized by FT-IR, UV-vis spectroscopic techniques, SEM, thermal and elemental analysis. The effect of reaction parameters such as solvent and oxidant in the epoxidation of cis-cyclooctene were also investigated. (C) 2006 Elsevier B.V. All rights reserved.