Characterization of the gold(II) dimer [Au(CH2)2PPh2]2(CH2Cl)Br: structural evidence suggesting the formation of a carbene intermediate preceeding A-frame (bridging methylene) formation

Abstract

[Au(CH₂)₂PPH₂]₂, (1), reacts with neat CH₂ClBr to give [Au(CH₂)₂PPH₂]₂(CH₂Cl)Br, (2), and the X-ray structure of (2), shows a close contact between one Au centre and the Cl of the co-ordinated CH₂Cl [2.895(16)Ă]; this interaction is consistent with the observed further oxidative addition of the CH₂Cl to form the bridging methylene A-frame complex, and suggests that a carbene intermediate may be involved.