Selective oxygenation of olefins with hydrogen peroxide catalyzed byiron(ii) bipyridine complex included in nay zeolite under visible lightirradiation

A novel visible light photocatalyst of iron(II) bipyridine complex encapsulated within NaY zeolite forselective oxygenation of styrene with high turnover (1800) and high benzaldehyde selectivity (86%) usinghydrogen peroxide as the oxidant under ambient conditions was explored. This photocatalyst was alsoeffective for the oxidation of other olefins, such as 4-cyanostyrene, 4-methoxystyrene, 3-methylstyrene,1,1-diphenylethylene, cis-stilbene, trans-stilbene, trans- β-methylstyrene, α-methylstyrene, triph-enylethylene, 1-octene, 2-octene, cyclohexene and cyclooctene, into the corresponding aldehydes,ketones or olefin oxides. The study shows that the photooxygenation of styrene occurs within thesupercages of zeolite Y, the products benzaldehyde and formaldehyde escape into the solution afterreaction, leading to high turnovers. Based on the experimental results, the photooxidation mechanism isalso discussed.