Copper-Catalyzed Direct C-H Arylation of Thieno[3,4-c]pyrrole-4,6-dione (TPD): Toward Efficient and Low-Cost Synthesis of π-Functional Small Molecules

A series of thieno[3,4-c] pyrrole-4,6-dione (TPD)-based functional small molecules were efficiently synthesized through direct C-H arylations using inexpensive copper salts. In this study, we examined all required reaction parameters including various copper complexes, ligands, bases, and (co)-solvents. Under the optimum reaction conditions, the C-H arylation proceeded smoothly and a variety of functional groups such as ester, nitrile, fluoride, chloride, triazene, and amine were tolerated. This method provides a step-economical and relatively low-cost synthetic alternative to presently used coupling reactions for the preparation of TPD-containing p-functional materials.