Synthesis and Platinum Complexes of an Alane‐Appended 1,1′‐Bis(phosphino)ferrocene Ligand

An aryldimethylalane-appended analogue of 1,1'-bis(diphenylphosphino)ferrocene, FcPPAl, was prepared, and reaction with [Pt(nb)3 ] (nb=norbornene) afforded [Pt(η(2) -nb)(FcPPAl)] (1). Heating a solution of 1 to 80 °C resulted in crystallization of [{Pt(FcPPAl)}2 ] (2), whereas treatment of 1 with C2 H4 , C2 Ph2 , H2 , or CO provided [PtL(FcPPAl)] [L=C2 H4 (3), C2 Ph2 (4)], [PtH2 (FcPPAl)] (5), and [Pt(CO)(FcPPAl)] (6). In all complexes, the FcPPAl ligand is coordinated through both phosphines and the alane. Whereas 2 adopts a T-shaped geometry at platinum, 3-5 are square-pyramidal, and 6 is distorted square-planar. The hydride and carbonyl complexes feature unusual multicenter bonding involving platinum, aluminum, and a hydride or carbonyl ligand.