Thermal properties of metal-metal bonded Pd(I) complexes supported onto porous Vycor glass

Abstract

Thermal behavior of the complexes Pd 2 (dppm) 2 Cl 2 , Pd 2 (dppm) 2 (SnCl 3 )Cl and Pd 2 (dppm) 2 (SnCl 3 ) 2 (dppm = bis[diphenylphosphino(methane)], ((C 6 H 5 ) 2 PCH 2 P(C 6 H 5 ) 2 ) in the solid state and immobilized onto porous Vycor glass was studied. Similar decomposition mechanisms were observed for the solid and immobilized complexes, with a small thermal stabilization upon immobilization. The decomposition products were characterized by X-ray diffractometry, Raman and diffuse reflectance infrared spectroscopy, which indicated the presence of a mixture of metallic palladium and oxidized species such as PdO, condensed phosphates, SnO 2 and SnP 2 O 7 . According to X-ray diffractometry, the decomposition products of the immobilized complexes presented higher amounts of PdO than the solid-state residues, probably as an effect of interactions with silanol groups present in the glass surface.