Direct Arylation Polycondensation Using Click‐Generated 1,2,3‐Triazole Monomers

ABSTRACT

Direct arylation polycondensation (DArP) offers a promising route to π‐conjugated polymers while avoiding the use of organometallic monomers and minimizing environmentally hazardous by‐products. However, the scope of applicable monomers remains limited because efficient CH activation requires highly reactive substrates. In this study, we explore the use of click‐derived 1,2,3‐triazole units as reactive sites for DArP. Bistriazole monomers were synthesized via azide–alkyne cycloaddition and subjected to polycondensation with dibromoarenes. Optimization of the reaction conditions revealed that pivalic acid as a carboxylic acid additive, palladium chloride as the catalyst, and DMAc as the solvent enabled successful polymerization with moderate molecular weights and isolated yields. Structural variations in the bistriazole monomers significantly influenced reactivity, with flexible alkyl linkers suppressing polymerization and certain triazole structures inhibiting the direct arylation process. Substrate studies further demonstrated that electronic and steric effects of dibromoarenes strongly affect polymerization efficiency. A rigid bistriazole monomer afforded an alternating copolymer, whose optical properties indicated disrupted π‐conjugation due to torsional twisting at triazole–aryl linkages. This work demonstrates that click‐derived triazole structures can serve as viable building blocks for direct arylation polycondensation and provides design guidelines for expanding monomer scope and structural diversity in DArP‐derived polymers.