Optical and electrochemical properties of oligo(1,5‐dialkoxynaphthalene‐2,6‐diyl)s with self‐assembled ordered structures in solid state

Oligo(1,5‐dialkoxynaphthalene‐2,6‐diyl)s were synthesized by Ni(cod)₂ (cod = 1,5‐cyclooctadiene)‐promoted condensation reactions of 1,5‐dialkoxy‐2,6‐dibromonaphthalenes. The UV–Vis, photoluminescence (PL), and powder X‐ray diffraction (XRD) measurements suggested that the oligomers have a self‐assembling ordered structure in the solid state. The oligomers underwent electrochemical oxidation (p‐doping), which occurred at lower potentials for films than for acetonitrile solutions containing Et₄N]BF₄. This effect is caused by the longer π‐conjugation lengths of the oligomers in films, which was attributed to molecular self‐assembly leading to ordered structures in the solid state. The electrochemical reaction of the oligomers was accompanied by electrochromism. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41840.