Palladium and platinum pyrimidine-2-thionate complexes with diphosphines

[MCl2(P–P)] (M = Pd and Pt; P–P = dppe and dppm) reacts with NaC4H3SN2, in a 1:2 molar ratio at room temperature, to give [M(S-C4H3SN2)2(dppe)] [M = Pd (1); M = Pt, (2)], [Pd(S-C4H3SN2)2(dppm)2] (3) and trans-[Pt(S-C4H3SN2)2(dppm)] (5), as well as other by-products such as [Pd2(S,N-C4H3SN2)4] (4) and trans-[Pt(S-C4H3SN2)2(PPh2Me)2] (6). A possible mechanism for the formation of 6, which requires cleavage of P–C bonds of the dppm ligands, is proposed.

Graphical abstract[MCl2(P–P)] (M = Pd and Pt; P–P = dppe) reacts with pyrimidine-2-thionate NaC4H3SN2, in a 1:2 molar, to give [M(S-C4H3SN2)2(dppe)] although with P–P = dppm and depending on the metal, Pt or Pd different complexes are obtained as represented on the scheme, including the formation of PPh2Me complex from dppm derivative.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Synthesis and X-ray structure of dppm and dppe complexes of palladium, platinum with pyrimidine-2-thionate. ► Formation of of PPh2Me complex from dppm derivatives which requires the cleavage of P–C bond. ► A plausible mechanism for the P–C cleavage is proposed.