Poly(thiophene iminoborane): A Poly(thiophene vinylene) (PTV) Analogue with a Fully BN‐Doped Backbone

Abstract

AbstractAn unprecedented poly(thiophene iminoborane)—a boron–nitrogen analogue of the well‐established conjugated organic polymer poly(thiophene vinylene)—is presented. The polymer synthesis is achieved by selective Si/B exchange polycondensation of a 2,5‐diborylthiophene with a 2,5‐diaminothiophene derivative. For the latter, a facile synthetic strategy is devised, which makes this versatile, strongly electron‐releasing building block easily accessible. The novel polymer and a series of monodisperse thiophene iminoborane oligomers reveal systematic bathochromic shifts in their absorption with increasing chain length, and thus extended π‐conjugation over the BN units along the backbone, which is further supported by TD‐DFT calculations.