Synthesis of unsymmetrical 2,3-diaryl- and 2,4-diarylthiophenes starting from 2,5-dichlorothiophene

Article abstract of DOI:10.1246/bcsj.67.2187

Unsymmetrically substituted 2,4-diaryl- and 2,3-diarylthiophenes were synthesized from 2,5-dichlorothiophene via 4-aryl-2-chlorothiophenes in two and four steps including Ni-mediated cross-coupling, respectively. Aluminum chloride-catalyzed reaction of 3-aryl-2-chlorothiophenes with some aromatic ethers unexpectedly led to the formation of the corresponding 2,4-isomers.