Effects of Regioregularity of pi-Conjugated Polymers Composed of Boron beta-Diketiminate on Their Stimuli-Responsive Luminescence

π-Conjugated polymers composed of a boron β-diketiminate complex with different regioregularity are synthesized by using Suzuki–Miyaura and Yamamoto couplings. The films formed with the polymers show luminescence chromism upon exposure to solvent vapors. Most importantly, the chromic behavior depends on the regioregularity of the polymers. Wide-angle X-ray diffraction, thermal analysis, and density functional theory calculations suggest that the chromism can originate from the morphological change in the films and the alternation of the electronic nature of the main chains