Conversion of methane to ethylene using an Ir complex and phosphorus ylide as a methylene transfer reagent

Abstract

Cp*(Me₃P)Ir(CH₃)(OTf), a complex known to reversibly activate CH₄ and other hydrocarbons under mild conditions, reacts with the phosphorus ylide H₂CPPh₃ in THF to afford two major species [Cp*(Me₃P)(Ph₃P)Ir(CH₂CH₃)][OTf] and [Cp*(Me₃P)Ir(H)(η²-CH₂CH₂)][OTf]. Insertion of the ylide methylene group can also occur with Cp*(Me₃P)Ir(Ph)(OTf) to afford the benzyl [Cp*(Me₃P)(Ph₃P)Ir(CH₂Ph)][OTf]. Theoretical studies suggest the intermediacy of an Ir(III)CH₂ species.