Synthesis of 4,4′-Dibutyl-5,5′-di(thiophen-3-yl)-2,2′-bithiazole for applications toward organic electronic material

Abstract

Except a few examples, solution-processable π-conjugated small molecules with both positive and negative type doping abilities are rare. This is a very important requirement for synthesizing ambipolar organic electronic materials. So, here a new bithiazole based small molecule 4,4′-dibutyl-5,5′-di(thiophen-3-yl)-2,2′-bithiazole (3TBTz) was synthesized and characterized by 1H NMR, 13C NMR and HRMS. An optimized (DFT-6-31G(d)-B3LYP) cation radical of 3TBTz attained completely planar geometry from a non-planar parent molecule optimized at the same level. Both, computationally (TD-DFT/CAM-B3LYP) and experimentally obtained UV–vis spectra found a decent match. The theoretically obtained reorganization energy for 3TBTz claimed superiority in comparison to its terthiophene analogue. The ambipolar red/ox profile observed in cyclic voltammetry was supported by DFT calculation.