A Modular and Regioselective Synthesis of Di- and Triarylated Thiophenes: Strategies for Accessing Challenging Isomeric Motifs

This work demonstrates a highly modular, fully regioselective, and high-yielding route to accessing a variety of multiarylated thiophene motifs. Specifically, this method was used to generate unique diarylated (2,5 or 3,5 or 4,5), triarylated (2,3,5 or 2,4,5 or 3,4,5), and tetra-arylated (2,3,4,5) thiophenes, and branched oligothiophenes. Our approach enables independent introduction of each arene, providing full control over the desired molecular structure. Given that 2,5-aryl-substituted thiophenes are highly sought-after and that aryl substitution at the 3 and 4 positions was previously highly challenging to obtain, our approach represents a facile means to generate these attractive molecules for the next generation of thiophene-based technologies.