Polyphenylens, Cross‐Linked Through Pd‐Carbene Complexes Formation, for Catalysis in Suzuki‐Miyaura Reactions

Abstract

AbstractPolyphenylenes supported N‐heterocyclic carbene Pd‐complexes were synthesized for catalysis of cross‐coupling Suzuki‐Miyaura reactions. Starting polyphenylenes were prepared by cyclocondensation reaction of diacetylaromatic with monoacetylaromatic compounds. N‐metylimidazole has been involved to the polymer through the mono‐functional acetyl monomer, in which in p‐position to acetyl group the group of haloalkyl was situated, and haloalkyl group interacted with N‐methylimidazole. N‐heterocyclic carbene complexes of Pd were synthesized usually by the reaction of imidazolium salts with the salts of transition metals in the presence of a base, obtaining the complex (N‐heterocyclic carbene)2PdX2. The catalysis reaction was carried out between arylhalides (iodo‐ or bromobenzene) and phenylboronic acid with the presence of 1 mol% of Pd. The yields of biphenyl are from 70 to 95%, which is comparable with homogeneous catalysis.