Mechanistic aspects of monomer, polymer formation, and synthesis of PQ-alt-dialkyl-fluorene conjugated copolymer

Suzuki coupling reaction is widely used in the construction of conjugated polymers; however, there is still no report describing the mechanism and coupling of 9, 10-phenanthrenequinone(PQ) building blocks via Suzuki reaction because PQ is sensitive to bases and light. Herein is reported the efficient Suzuki coupling of PQ with 9,lO-dialkylfluorene with Na₂C0₃ as basic species and high molecular weight PQ-Alt-Dialkyl-Fluorene conjugated copolymer obtained in an yield of 42%. Based on the characterization data and well-accepted literature, we proposed a step-by-step mechanistic explanation for the formation of the PQ containing alternating conjugated copolymer.