| Περίληψη: | The synthesis, as well as the structural and spectroscopic characterization of the palladium(II) complex [Pd{(Ph2P)2N(CH2)3Si(OCH3)3-κP,P′}I2], bearing the bis(phosphino)amine ligand (P,P) = (Ph2P)2N(CH2)3Si(OCH3)3, is described. X-ray crystallography studies revealed a square planar PdP2I2 coordination sphere, the structural features of which are compared with those of analogous nickel(II), palladium(II) and platinum(II) complexes. The three complexes [Pd(P,P)X2], X = Cl, Br, I, along with [Pd{(Ph2P)2N((S)-CHPhMe)-κP,P′}Cl2] and [Pd{(Ph2PSe)(Ph2P)N((S)-CHMePh)-κP,Se}Cl2], were tested as catalysts in homogeneous hydroalkoxycarbonylation reactions. The hydroalkoxycarbonylation of styrene proved to be perfectly regioselective towards the branched ester. Complex [Pd(P,P)Cl2] showed remarkably higher activity compared with that of [Pd(P,P)X2], X = Br, I. Furthermore, complex [Pd(P,P)I2] was studied as a homogeneous catalyst precursor in the Suzuki–Miyaura C−C coupling reaction between aryl bromides and phenylboronic acid. Complex [Pd(P,P)I2] was immobilized onto STx–1 montmorillonite clay and the catalytic reactivity of the heterogenized catalyst was also investigated in both hydroalkoxycarbonylation and Suzuki–Miyaura reactions. |
