Synthesis of Conjugated Polymers Containing Octafluorobiphenylene Unit via Pd-Catalyzed Cross-Dehydrogenative-Coupling Reaction

ACS Macro Lett. 2018 Jan 16;7(1):90-94. doi: 10.1021/acsmacrolett.7b00887. Epub 2017 Dec 26.

Abstract

Polycondensation via Pd-catalyzed cross-dehydrogenative-coupling reaction of 2,2',3,3',5,5',6,6'-octafluorobiphenyl with thiophene analogues was studied. The synthetic protocol, in which employment of prefunctionalized starting monomers was fully avoided, allowed straightforward access to an alternating π-conjugated polymer. The addition of K2CO3 to the catalytic system promotes the cross-coupling reaction and suppresses the undesired homocoupling reaction, producing the corresponding donor-acceptor type π-conjugated polymers with minor homocoupling defects. The reaction also proceeded using O2 as the terminal oxidant, resulting in lower loading of the Ag oxidant. The obtained polymer was evaluated as an emitting material for an organic light-emitting diode.