22. "Synthesis and Structure of Dinuclear Palladium(II) Complexes with Bridging Hydrido and Phosphido Ligands," Michael A. Zhuravel, Jillian R. Moncarz, David S. Glueck, Kin-Chung Lam, and Arnold L. Rheingold, Organometallics 2000, 19, 3447-3454.

Abstract The reaction of Pd(dppf)(Ph)(I) (1, dppf = Ph₂PC₅H₄FeC₅H₄PPh₂) with 1.5 equiv of PPh₂H leads to the formation of the Pd(II) dinuclear complex Pd₂I₂(m-dppf)(m-H)(m-PPh₂) (2) and the phosphines PPh₃ and dppf. The reaction of 1 with 1 equiv of PCy₂H (Cy = cyclo-C₆H₁₁) slowly gives Pd₂I₂(m-dppf)(m-H)(m-PCy2) (3). Complex 2 reacts further with PPh₂H to give the known [Pd(m-PPh₂)(I)(PPh₂H)]₂ (4). Reaction of Pd(dcpm)(Ph)(I) (dcpm = Cy₂PCH₂PCy₂) with PPh₂H gives [Pd₂(PPh₂H)₂(m-dcpm)(m-PPh₂)][I] (5). Treatment of Pd(dmpe)(Me)(Cl) (dmpe = Me₂PCH₂CH₂PMe₂) with AgOTf and PPh₂H gives [Pd(dmpe)(m-PPh₂)]₂[OTf]₂ (6, OTf = OSO₂CF₃) as well as a small amount of [Pd₂(dmpe)₂(m-H)(m-PPh₂)][OTf]₂ (7). Slow decomposition of [Pd(dmpe)(Me)(PCy₂H)]⁺, prepared by the reaction of Pd(dmpe)(Me)(Cl), AgOTf and PCy₂H, gives [Pd₂(dmpe)₂(m-H)(m-PCy₂)][OTf]₂ (8), which was also prepared from Pd(dmpe)Cl₂, AgOTf, Pd(dmpe)(dba) (dba = dibenzylideneacetone) and PCy₂H. Complexes 3, 4, 5, and 8 were structurally characterized by X-ray crystallography.