Epoxidation of olefins catalyzed by [pi-C5H5NC16H33](3) [PW4O16] with molecular oxygen and a recyclable reductant 2-ethylanthrahydroquinone

In the epoxidation system of [pi -C5H5NC16H33](3)[PW4O16]/molecular oxygen/ recyclable reductant (2-ethylanthrahydroquinone), cyclohexene, terminal ole fins and allyl chloride all underwent epoxidation reactions smoothly under mild conditions. Good selectivities to epoxides and high reductant utilizat ion efficiencies (72.6-94.5%) were achieved. From 1-dodecene to 1-hexene, t he epoxidation reactivity of the olefin and the utilization efficiency of t he reductant increased with the decrease of carbon atoms in terminal olefin s. Studies showed that H2O2 produced by the oxidation of 2-ethylanthrahydro quinone with molecular oxygen was the key intermediate that afforded the di rect epoxidation of the substrate. (C) 2001 Elsevier Science B.V. All right s reserved.