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 (M n = 2600, M w /M n = 1.6) was obtained in a 76% yield by the polymerization of 1,4-diiodobenzene, diphenylacetylene, and 1,4-phenylenediboronic acid in DMF/H 2 Ο at 100°C for 24 h in the presence of PdCl 2 (PhCN) 2 (1 mol%) and KHCO 3 . The obtained polymer is soluble in organic solvents such as CHCl 3 , THF, and toluene, although it does not have any soft lateral segments.