Trimethylstannyl (diphenylphosphino)acetate: a source of (diphenylphosphino)acetate ligand in the synthesis of coordination compounds

Trimethylstannyl (diphenylphosphino)acetate (1), which is readily accessible from potassium (diphenylphosphino)acetate and trimethylstannyl chloride, may serve as the source of (diphenylphosphino)acetate anion in the preparation of coordination compounds. Thus, the reactions between [M(cod)Cl2] (M = Pd and Pt; cod = η2:η2-cycloocta-1,5-diene) and two equivalents of 1 give [M(Ph2PCH2CO2-κ2O,P)2] (2 and 3), while the reaction of [{Pd(μ-Cl)Cl(PFur3)}2] (4; Fur = 2-furyl) with one equivalent of 1 yields [SP-4-3]-[PdCl(Ph2PCH2CO2-κ2O,P)(PFur3)] (5). The reactions of 1 with the dimers [{Rh(η5-C5Me5)Cl(μ-Cl)}2] and [{Ru(η6-1,4-MeC6H4(CHMe2))Cl(μ-Cl)}2] (at 1-to-metal ratio 1:1) produce O,P-chelated complexes as well, albeit as stable adducts with the liberated Me3SnCl: [RhCl(η5-C5Me5)(Ph2PCH2CO2-κ2O,P)] · Me3SnCl (6) and[RuCl(η6-1,4-MeC6H4(CHMe2))(Ph2PCH2CO2-κ2O,P)] · Me3SnCl (8). The related complexes with P-monodentate (diphenylphosphino)acetic acid, [RhCl2(η5-C5Me5)(Ph2PCH2CO2H-κ,P)] (7) and [RuCl2(η6-1,4-MeC6H4(CHMe2))(Ph2PCH2CO2H-κP)] (9), were obtained by bridge splitting in the dimers with the phosphinocarboxylic ligand. All new compounds were characterized by spectral methods and combustion analyses, and the structures of 2 · 3CH2Cl2, 3, 4, 5, 6 and 8 were determined by X-ray crystallography.