Synthesis, Fluorescence Properties, and Head-to-Tail Regioselectivity in the Photodimerization of a Donor–Acceptor-Substituted Anthracene

The novel 2,6-donor–acceptor-substituted anthracene, namely 6-methoxy-2-anthracene carboxylic acid (7), was synthesized. The emission of this compound exhibits significant solvatochromism. The fluorescence band position and intensity are also remarkably sensitive to H+. Irradiation of the anthracene 7 in solution yields the syn and anti head-to-tail dimers exclusively. A synergistic electronic effect between the donor and acceptor substituents is proposed to operate on the photophysical and photochemical properties of anthracene 7.