Hydrocarbon oxidation with iodosylbenzene catalysed by the sterically hindered iron(III) 5-(pentafluorophenyl)-10,15,20-tris(2,6-dichlorophenyl)porphyrin in homogeneous solution and covalently bound to silica

Abstract

Iron(III) 5-(pentafluorophenyl)-10,15,20-tris(2,6-dichlorophenyl)porphyrin has been synthesised and used to catalyse hydrocarbon oxidation by iodosylbenzene. In homogeneous solution it is shown to be a stable and effective catalyst for alkene epoxidation and alkane hydroxylation with a selectivity and reactivity closer to iron(III) tetrakis(pentafluorophenyl)porphyrin than to iron(III) tetrakis(2,6-dichlorophenyl)porphyrin. The new sterically hindered iron porphyrin has also been covalently bound, by nucleophilic aromatic substitution to aminopropylated silica. The resulting heterogenised catalyst is also stable towards oxidation but is less reactive than its homogeneous analogue.