Polymer-round Schiff-base complex catalyst for effective oxidation of olefins with molecular oxygen

Polymer-bound Schiff-base ligand (PS-SalPhe) was prepared from polystyrene- bound salicylaldehyde and phenylalanine, and its complex (PS-SalPhe-M) (M = Co, Mn) was also synthesized. The polymer ligand and its complex were char acterized by infrared spectra, small area X-ray photoelectron spectroscopy, and ICP-AES. In the presence of the complex, cyclohexene can be effectivel y oxidized by molecular oxygen without a reductant. The major products of t he reaction are 8-cyclohexen-1-ol (-OH), 2-cyclohexen-1-one (C=O), and 2-cy clohexen-1-hydroperoxide (-OOH), which is different from the typical oxidat ion of cyclohexene. The mechanism of cyclohexene oxidation is also discusse d. Long-chain linear aliphatic olefins, such as 1-octene, 1-decene, 1-dodec ene, and 1-tetradecene, can be directly oxidized by molecular oxygen cataly zed by PS-SalPhe-M (M = Mn, Co), which yields the 1,2-epoxy alkane. (C) 200 0 John Wiley & Sons, Inc.