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 dichalcogetioamidodiphosphinate anions are reported. The complexes [Pd (eta(3)-CH2C(R)CH2){R-2'P(E)NP(E)R'(2)-E,E'}] [R'-H, R'= Pr-i, E = S (1a); R = H, R'= Pr-i, E = Se (1b); R = H, R'= Ph, E = S (1c); R = H, R' = Ph, E = Se (1d); R = Me, R'= Pr-i, E = S (2a); R = Me, R'= Pr-i, 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(eta(3) -CH2C(R)CH2)(acac)] (acac = acetylacetonate) with dichalcogenoimidodiphosphinic acids in acetonitrile solution. The complexes have been characterized by multinuclear NMR (H-1, C-13 {H-1), P-31{H-1}, Se-77(H-1)), FT-IR and elemental analyses. The crystal structures of complexes la, Id and 2d have been reported and they consist of a six-membered PdE2P2N ring (E = S for la 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. (c) 2006 Elsevier B.V. All rights reserved.