Synthesis of donor–acceptor conjugated polymers based on benzo[1,2-b:4,5-b′]dithiophene and 2,1,3-benzothiadiazole via direct arylation polycondensation: towards efficient C–H activation in nonpolar solvents

摘要: This article describes the synthesis of donor–acceptor (D–A) type copolymers based on benzo[1,2-b:4,5-b′]dithiophene and 2,1,3-benzothiadiazole via direct-arylation cross-coupling polycondensation. To achieve high performance polymerization, we have systematically investigated reaction factors including catalysts, solvents, ligands, bases, additives, concentration reactants phase transfer agents. In particular, 1,2-dimethylbenzene (ODMB), as a nonpolar boiling point solvent, is superior medium to perform this polymerization. aromatic Pd2dba3/(o-MeOPh)3P, accompanied with base potassium carbonate an additive pivalic acid, serves efficient catalyst system obtain high-quality polymers. Our optimized condition gave polymer weight-average molecular weight (Mw) 60 kg mol−1 in nearly quantitative yield excellent C–H selectivity.