Weiss-Cook Condensations for the Synthesis of Bridged Bithiophene Monomers and Polymers

We report on the design, synthesis and properties of innovative π-conjugated compounds in which a 2,2’-bithiophene ring system embeds a functionality-rich C(sp3)-C(sp3) carbon bridge. The synthesis is achieved in high yields making use of a one-pot sequence of Weiss-Cook condensation as the key step, followed by decarboxylation. The monomers can be polymerized with appropriate comonomers via Pd-catalyzed crosscoupling, thus rapidly approaching rigid, functionality-rich bithiophene containing conjugated polymers.