Selective alkene epoxidation and alkane hydroxylation with sodium periodate catalyzed by cationic Mn(III)-salen supported on Dowex MSC1

摘要

Dicationic Mn(III)-salen,containing phosphonium groups at 5,5'-positions of salen ligand,is supported on an ion-exchange resin,Dowex MSC1,via electrostatic interaction.The catalyst,Mn(salen)-Dowex,has been characterized by FTIR,UV-vis spectroscopic techniques,scanning electron micrograph (SEM),thermal and elemental analysis.This heterogenized homogeneous manganese(III)-salen complex can be used as catalyst in the alkene epoxidation with sodium periodate.This catalytic system shows a good activity in the epoxidation of cyclic,aromatic and especially linear alkenes and exhibits a high selectivity in epoxidation of alpha-pinene and R-(+)-limonene.Alkyl aromatic and cycloalkanes were oxidized efficiently to their corresponding alcohols and ketones in the presence of this catalyst.The stability and reusability of this new heterogenized metallosalen complex was also investigated.