Chiral Octapalladium Chains Supported by Enantiopure -Stereogenic Linear Tetraphosphines, ()- and ()-PhPCHP(Ph)CHP(Ph)CHPPh.

Binuclear Pd(II) and Pt(II) complexes supported by -dpmppm (bis[(diphenylphosphinomethyl)phenylphosphino]methane) in a triply-bridged -form, [MCl(-dpmppm)] (M = Pd (), Pt ()), readily reacted with 2,6-xylyl isocyanide (XylNC) in the presence of NHPF to afford [MCl(-dpmppm)(XylNC)](PF) (M = Pd (), Pt ()), in which each metal center accommodates one isocyanide ligand at the position to the inner P atom of dpmppm. Similarly, treatment of and with axially chiral ()-1,1'-binaphthyl-2,2'-bisisocyanide (-Binac) in the presence of NHOTf gave cyclic tetranuclear complexes, [{MCl(-dpmppm)(-Binac)}](OTf) (M = Pd (), Pt ()), where two {MCl(-dpmppm)} fragments are connected by two -Binac ligands through chirality sorting of ()-dpmppm and ()-Binac. Complex could be transformed into the halide exchanged tetranuclear complexes, [{PdX(-dpmppm)(-Binac)}](OTf) (X = Br (), I ()), to show that the rectangular arrangement of four Pd(II) ions is elongated by repulsive interaction between halide ligands.