Planarization of Conjugated Biaryls through B-N Interactions

Significance

The formation of a boron-nitrogen bond is utilized to constrain conjugated biaryl units in a fully coplanar conformation. Due to the extended conjugation that arises from the locked-in conformation, the resulting quateraryls exhibit improved electron mobility. Intramolecular Lewis acid coordination of the electron-poor thiazole unit also facilitates n-doping by lowering the LUMO levels.