Symmetrical η1–, or σ–π-acetylide bridges in bimetallic µ-Ph2PCH2PPh2(dppm) complexes: crystal structures of [MePt(µ-η1–CCMe)(µ-dppm)2PtMe][BF4] and [CIPT(µ-σ–π-CCMe)(µ-dppm)2Rh(CO)][PF6]

Abstract

[MePt(µ-dppm)₂PtMe]²⁺[dppm = bis(diphenylphosphino)methane; Ph₂PCH₂PPh₂] reacts with terminal acetylenes to give a µ-η^2–HCCR complex, which readily deprotonates to give the symmetrically bonded µ-η¹-CCR complex: in contrast, in the platinum-rhodium complex, the acetylide is σ-bonded to the platinum and sideways (π) bonded to the rhodium.