3-Dimethylaminopropyl chalcogenolate complexes of palladium(II): Syntheses and characterization, including the crystal structures of [Pd(OAc)(ECH2CH2CH2NMe2)]2 · H2O (E = S, Se) and [PdCl(TeCH2CH2CH2NMe2)]2

The reactions of the sodium salts of 3-dimethylamino-1-propylchalcogenolates, prepared by sodium borohydride reduction of (Me2NCH2CH2CH2E)2 in methanol, with Na2PdCl4 yielded homoleptic [Pd(ECH2CH2CH2NMe2)2]6 (1) (E = S (1a); Se (1b); Te (1c)). When treated with [Pd(OAc)2]3 or Na2PdCl4, compounds 1 readily gave binuclear redistribution products [PdX(ECH2CH2CH2NMe2)]2 where X = OAc (2) (E = S (2a); Se (2b); or Cl (3)) (E = S (3a); Se (3b); Te (3c)), respectively. The terminal acetate/chloride ligands in 2b/3b can be substituted by other ionic ligands like PhSe−. The complexes were characterized by elemental analysis, UV–Vis, IR and NMR spectroscopy. The structures of 2a, 2b and 3c were established by X-ray crystallography. Each molecule has a dimeric structure in which there are two chalcogenolate bridges from the chelating 3-dimethylamino-1-propylchalcogenolate ligands. On pyrolysis, compound 2b affords Pd17Se15.