Nickel Nanoparticles Supported on Diphenylphosphinated Poly(Vinyl Alcohol-Co-ethylene) as a New Heterogeneous and Recyclable Catalyst for Mizoroki–Heck Reactions

Abstract

Nickel nanoparticles (NiNPs) supported on diphenylphosphinated poly(vinyl alcohol- co-ethylene) (DPP-PVA- co-PE) were synthesised by first reacting poly(vinyl alcohol- co-ethylene) with chlorodiphenylphosphine (ClPPh2) under basic conditions and then treating the product with Ni(OAc)2 followed by reduction with NaBH4. (DPP-PVA- co-PE)-NiNPs, a new metallised polymer, was then shown to efficiently catalyse Mizoroki–Heck reactions of aryl iodides, bromides or activated chlorides with olefins such as styrene and n-butyl acrylate in dimethylformamide. In contrast with other polymer-supported catalysts, the main advantage of this method is the low cost of the catalyst due to the simple synthetic route using easily obtained materials and good recoverability. Transmission electron microscopy and X-ray diffraction measurements were used to show the high metal dispersion and small sizes of Ni nanoparticle on the surface of the modified polymer. DPP-PVA- co-PE-NiNPs could be recycled several times.

Role of Polymer Structures in Catalysis by Transition Metal and Metal Oxide Nanoparticle Composites

“…In another example, Ni-containing catalysts have been synthesized by the NaBH 4 reduction of the Ni precursor on diphenylphosphinated poly­(vinyl alcohol- co -ethylene) and studied in Mizoroki–Heck reactions of aryl iodides, bromides, or activated chlorides with olefins . Despite the low cost of the metal used and high yields (up to 90–95%) of target products for some substrates in optimized reaction conditions, a poor characterization of these catalysts make it difficult to judge the outcome of this work.…”