Multinuclear magnetic resonance studies of the reactions of bidentate ligands with Pt(S2P(OEt)2)2. Crystal and molecular structure of (apeS)Pt(S2P(OEt)2)2 (ApeS = Ph2AsCH2CH2P(S)Ph2)

The interactions in dichloromethane solution of Pt(S2P(OEt)2)2 (I) with a number of potentially bidentate ligands have been studied by multinuclear (31P, 77Se, 195Pt) magnetic resonance techniques. The ligands used (L-L') were Ph2PCH2CH2PPh2 (dpe), Ph2AsCH2CH2PPh2 (ape), Ph2PCH2PPh2 (dpm), Ph2PCH2P(E)Ph2 (E = S, Se to give dpmS, dpmSe), and Ph2PCH2CH2P(E)Ph2 (apeS, apeSe). All the ligands except apeS and apeSe react with (I) in 1:1 proportions to give initially ((L-L')Pt(S2P(OEt)2))+ and free (S2P(OEt)2)-, but a slower reaction gives (L-L')Pt(S2P(O)OEt) and EtS2P(OEt)2 by attack of the free anion on the coordinated dithiophosphate ligand. In 1:2 proportions these ligands give (Pt(L-L')2)2+ and free (S2P(OEt)2)-, except for dpm which gives ((η1-dpm)(η2-dpm)Pt(η1-S2P(OEt)2))+. The same products are obtained by reacting 1 mol of L-L' with 1 mol of ((L-L')Pt(S2P(OEt)2))+, but the (L-L')Pt(S2P(O)OEt) compounds do not react with further L-L' ligand. The ligands apeE react with to give only (η1-apeE)Pt(η1-S2P(OEt)2)(η2-S2P(OEt)2). The structures of all the complexes in solution were determined by multinuclear magnetic resonance studies and that of (η1-apeS)Pt(η1-S2P(OEt)2)(η2-S2P(OEt)2) in the solid state was confirmed by a single-crystal x-ray diffraction study. 21 references, 4 figures, 8 tables