Immobilized Pd metal-complex on polymeric resin with high surface areas for recyclable catalyst: Effect of the immobilization method on nature of palladium species

A critical query on literature is the approach used to immobilize homogeneous catalysts to improve their efficiency and recyclability. This work aims to compare the immobilization level of a kind of Pd-N,N & PRIME;-bis(salicylidene)-o-phenylenediamine complex on high surfaces of polymeric resins to provide heterogenous catalysts for Mizorocki-Heck reaction. The preparation method involves two strategies: (i) polymerization of the ligand before the complex-synthesis in a "multi-step (MS) " approach and (ii) a direct "one-step " (OS) immobilization by polymerization of the metal-containing monomers (MCMs) as co-monomer. Both approaches effectively yield polymers with a larger surface area, over 700 m(2) g(-1), and suitable thermic properties to use in the proposed reaction. In addition, the characterization of the polymers by XRD, XPS, and TEM demonstrates notable differences in Pd species on polymer support associated with the methodological approach to immobilizing the metal complex.