Allylpalladium (II) complexes with dichalcogenoimidodiphosphinate ligands: Synthesis, structure, spectroscopy and their transformation into palladium chalcogenides

The synthesis, characterization and thermal behavior of new monomeric allylpalladium (II) complexes with dichalcogenoamidodiphosphinate anions are reported. The complexes View the MathML source[Pd(η3-CH2C(R)CH2){R′2P(E)NP(E)R′2-E,E′}] [R = H, R′ = Pri, E = S (1a); R = H, R′ = Pri, E = Se (1b); R = H, R′ = Ph, E = S (1c); R = H, R′ = Ph, E = Se (1d); R = Me, R′ = Pri, E = S (2a); R = Me, R′ = Pri, E = Se (2b); R = Me, R′ = Ph, E = S (2c); R = Me, R′ = Ph, E = Se (2d)] have been prepared by room temperature reaction of [Pd(η3-CH2C(R)CH2)(acac)] (acac = acetylacetonate) with dichalcogenoimidodiphosphinic acids in acetonitrile solution. The complexes have been characterized by multinuclear NMR (1H, 13C{1H}, 31P{1H}, 77Se{1H}), FT-IR and elemental analyses. The crystal structures of complexes 1a, 1d and 2d have been reported and they consist of a six-membered PdE2P2N ring (E = S for 1a and Se for 1d and 2d) and an allyl group, C3H4R(R = H for 1a and 1d and Me for 2d). Thermogravimetric studies have been carried out for few representative complexes. The complexes thermally decompose in argon atmosphere to leave a residue of palladium chalcogenides, which have been characterized by PXRD, SEM and EDS.