title: Green and Efficient: Iron-Catalyzed Selective Oxidation of Olefins to Carbonyls with O2.
abstract: A mild and operationally simple iron-catalyzed protocol for the selective aerobic oxidation of aromatic olefins to carbonyl compounds is described. Catalyzed by a Fe(III) species bearing a pyridine bisimidazoline ligand at 1 atm of O2, α- and β-substituted styrenes were cleaved to afford benzaldehydes and aromatic ketones generally in high yields with excellent chemoselectivity and very good functional group tolerance, including those containing radical-sensitive groups. With α-halo-substituted styrenes, the oxidation took place with concomitant halide migration to afford α-halo acetophenones. Various observations have been made, pointing to a mechanism in which both molecular oxygen and the olefinic substrate coordinate to the iron center, leading to the formation of a dioxetane intermediate, which collapses to give the carbonyl product.
authors.affiliation: Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, U.K.
authors.forename: Angela
authors.initials: A
authors.lastname: Gonzalez-de-Castro
authors.affiliation: Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, U.K.
authors.forename: Jianliang
authors.initials: J
authors.lastname: Xiao
mesh_terms: D000098:Acetophenones / Q000737:chemistry; D000475:Alkenes / Q000737:chemistry*; D001547:Benzaldehydes / Q000737:chemistry; D002384:Catalysis; D005290:Ferric Compounds / Q000737:chemistry*; D055772:Green Chemistry Technology; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D048288:Imidazolines / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry; D020058:Styrene / Q000737:chemistry
chemical_list: D000098:Acetophenones; D000475:Alkenes; D001547:Benzaldehydes; D005290:Ferric Compounds; D006841:Hydrocarbons, Aromatic; D048288:Imidazolines; D011725:Pyridines; D020058:Styrene; C023666:pyridine; C038699:acetophenone; D010100:Oxygen; C032175:benzaldehyde