Titanium Dioxide Nanoparticles Functionalized with Pd and W Complexes of a Catecholphosphane Ligand

Abstract

Palladium and tungsten complexes containing the bifunctional ligand 4-diphenylphosphanylcatechol (L1) have been synthesized. The catecholate functionality strongly binds to titanium dioxide nanoparticles, effectively anchoring the complexes to the TiO2 surface. Solid-state 31P NMR spectroscopy was used to probe the surface-bound compounds. Diffuse reflectance infrared spectroscopy also provided data on surface-bound tungsten carbonyl complexes. Preliminary experiments show that the palladium phosphane complex [PdBr2(L1)2] supported on TiO2 catalyzes the Sonogashira coupling of phenylacetylene with 4-iodonitrobenzene.