Synthesis of Poly(phenylene ethynylene) Using an Easily Recyclable Pd-Functionalized Magnetite Nanoparticle Catalyst

Abstract

An easily recyclable catalyst has already been used in several cross-coupling reactions, resulting in many advantages compared to commonly used homogeneous catalysts. Despite all these implementations of such removable catalysts, it has never been performed in the synthesis of conjugated polymers. Therefore, a Pd-functionalized magnetite nanoparticle was succesfully 2 synthesized and implemented in the synthesis of poly(phenylene ethynylene). The polymerization was performed using either an AB-monomer or A2/B2 monomers, and occurred in a classical stepgrowth fashion. Mn values over 10 kg/mol were obtained. Due to the presence of the magnetite nanoparticle, the catalyst could be removed and reused up to five times using magnetic precipitation. In addition, it reduces the amount of impurities present in the polymer, as a result of the Pd-catalyst, for up to 10 times compared to a commonly used homogeneous catalyst such as Pd(PPh3)4.

Recent Progress of Metal Nanoparticle Catalysts for C–C Bond Forming Reactions

“…A Fe 3 O 4 /oleic acid/Pd NPs catalyst was used for the Sonogashira polymerization. The polymerization occurred by a step-growth mechanism and resulted in a molar mass of 3.8 kg/mol [128]. The sequential Knoevenagel condensation/1,3-dipolar cycloaddition reactions proceeded using Fe 3 O 4 @SiO 2 @Au catalyst to give substituted spiroisoxazoines and oxadiazoles with good regio-and stereoselectivity under mild reaction conditions (Scheme 10) [129].…”

Preparation of Functionalized Superparamagnetic Fe3O4@Dopamine@Metal Ions (Cu+,Ru2+) Nanocomposites and its Catalytic Applications

“…To overcome this issue, the concept of introducing a linker between catalyst and solid support was presented by various research groups. This has helped in improving the long-term stability as well as the dispersity of the catalyst in reaction medium to obtain better catalytic efficiency [1,[8][9][10][11][12][13].…”