Controlled radical polymerization and conventional radical polymerization were used to prepare alkane-soluble poly(4-alkylstyrene) polymers and copolymers. Products containing 4-tert-butyl, 4-octadecylstyrene and 4-dodecylstyrene monomers were then used to prepare a dye-labeled homo- and copolymers. When these polymers were prepared with dye labels, they exhibited quantitative phase selective solubility in nonpolar phase in mixtures containing nonpolar solvent and immiscible polar solvent at 25o C making them good polymer candidates for recycling of catalysts as shown in Figure1. When these polymers were prepared with 5-10 mol% of 4-chloromethylstyrene to give poly(4-alkylstyrene-co-vinylbenzyl chloride) polymers that can undergo substitution of the benzylic chlorine they afforded useful precursors for catalyst ligands. For example, substitution with dicyclohexylphosphinobiphenyl ligand yields an electron-rich air stable polystyrene-bound phosphine ligand. Palladium complexes of poly(4-alkylstyrene)-bound phosphines were compared to those formed with a polyisobutylene (PIB), whose terminus was also converted into a dicyclohexylphosphinobiphenyl ligand. Both complexes were active and recyclable catalysts in haloarene-amine and haloarene-arylboronic acid couplings. Additionally, a diphenylstyrylphosphine ligand was incorporated onto the poly(4-dodecylstyrene) polymer via RAFT chemistry. The catalytic activity of these polymer-supported phosphine ligands and their recycling will be discussed.

Synthesis of a family of highly phase selectively soluble poly(4-alkylpolystyrene) supports for palladium-mediated homogeneous catalysis

247th National Meeting (2014)

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