Synthesis of Wholly Aromatic Polymers Possessing Tetra-aryl-substituted Vinylene Units by Palladium-catalyzed Three-component Coupling Polymerization

The synthesis of novel wholly aromatic poly(arylenevinylene)s containing tetra-aryl-substituted olefin units in the main chain by the three-component coupling polymerization of aryl dihalides, aryl diboronic acids, and acetylene derivatives is described. For instance, a polymer (Mn = 2600, Mw/Mn = 1.6) was obtained in a 76% yield by the polymerization of 1,4-diiodobenzene, diphenylacetylene, and 1,4-phenylenediboronic acid in DMF/H2O at 100 °C for 24 h in the presence of PdCl2(PhCN)2 (1 mol %) and KHCO3. The obtained polymer is soluble in organic solvents such as CHCl3, THF, and toluene, although it does not have any soft lateral segments.