Optically pure P-stereogenic methylphosphine− boranes P(BH 3 )PhArMe (Ar = 1-naphthyl (1-Np), 9-phenanthryl (1-Phen), 2-biphenylyl (1-Biph)) have been used to prepare six diphosphines of the type PPhAr−CH 2 −PR 2 (R = Ph or i-Pr; 3-ArR) with a methylene bridge between the phosphorus atoms and a single P-stereogenic moiety. The ligands have been reacted with [PdCl 2 (COD)] to furnish the corresponding [PdCl 2 (P−P′)] complexes. The reaction with [PdCl(η 3 -2-methylallyl)] 2 and NH 4 PF 6 has produced the expected [Pd(η 3 -2-methylallyl)(P− P′)]PF 6 complexes as stable species in solution only for the ligands containing the diisopropylphosphino group. The other ligands produced a mixture of species in solution, from which the dimeric complex [Pd 2 (η 3 -2-methylallyl) 2 (PNpPh-CH 2 -PPh 2 ) 2 ](PF 6 ) 2 , and the coordination compound [Pd(PBiphPh-CH 2 -PPh 2 ) 2 ](PF 6 ) 2 could be crystallographically characterized.

Enantiopure P-stereogenic methylphosphane-boranes (SP)-P(BH3)PhArMe (ArMe; Ar = 1-naphthyl (NpMe), and 2-biphenylyl (BiphMe)) have been used to prepare diphosphanes of the type ArPhPCH2PR2 (R = Ph, iPr or tBu; ArR). The...