Suzuki route to regioregular polyalkylthiophenes using Ir-catalysed borylation to make the monomer, and Pd complexes of bulky phosphanes as coupling catalysts for …
We have applied palladium complexes of bulky, electron-rich phosphane ligands as catalysts for the Suzuki synthesis of highly head-to-tail regioregular polyalkylthiophenes from 2-(5-bromo-4-n-alkyl-thiophen-2-yl)-4, 4, 5, 5-tetramethyl-[1, 3, 2] dioxaborolane. The monomer can be prepared in high yield by Ir-catalysed borylation of 2-bromo-3- hexylthiophene, without the need for organolithium reagents or strong bases.
