2-(Dimethylamino)ethaneselenolates of palladium(II): synthesis, structure, spectroscopy and transformation into palladium selenide

Bis[2-(dimethylamino)ethyl] diselenide was prepared by the reaction of Na2Se2 with ClCH2CH2NMe2. 2-(Dimethylamino)ethaneselenolate complexes of palladium(II) of the type [PdCl(SeCH2CH2NMe2)](3) 1, [PdCl(SeCH2CH2NMe2)(PR3)] 2, [Pd2Cl3(SeCH2CH2NMe2)(PR3)(2)] 3 and [Pd(SeCH2CH2NMe2)(2)(PPh3)(2)] 4 have been synthesized and characterized by elemental analysis, IR and NMR (H-1, P-31, Se-77) spectroscopy. The structures of orange 1 and of violet (lambda (max)=514 nm) 2c have been established by single crystal X-ray diffraction analyses. The trimer 1 contains a six-membered Pd3Se3 ring in twist conformation. The thermal behaviour of three complexes, yielding Pd17Se15 has been investigated.