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

Abstract

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.

Substituent Effects on the Absorption and Fluorescence Properties of Anthracene

“…This is in agreement with our calculated oscillator strength for this molecule, which is 0.13 compared to 0.10 for anthracene. Experimentally, 6-methoxyanthracene-2-carboxylic acid (2-carboxy-6-methoxyanthracene) has an absorption maximum at 3.31 eV, , which also compares well with our calculated value of 3.22 eV.…”

“…A more recent study focused on 2,6 doubly substituted anthracenes, and specifically 6-methoxyanthracene-2-carboxylic acid . The absorption maximum of this compound in methanol is 3.31 eV, whereas our calculated value in aqueous solution is 3.22 eV, in quite good agreement.…”

“…A more recent study focused on 2,6 doubly substituted anthracenes, and specifically 6-methoxyanthracene-2-carboxylic acid. 33 The absorption maximum of this compound in methanol is 3.31 eV, whereas our calculated value in aqueous solution is 3.22 eV, in quite good agreement. In a different study, 9-bromoanthracene in CCl 4 has a first peak at 3.16 eV whereas anthracene in the same solvent has a first peak at 3.27 eV, resulting in a red shift of 0.11 eV for 9-bromoanthracene.…”

Supramolecular Architecture of an Amphiphilic Amino Alcohol as a Versatile Chiral Environment for Stereocontrolled Photoreaction of Various Anthracenes

“…As a new series of photoreactants that meets the requisites (i)‐(iv) as described above, we designed and synthesized a series of anthracenecarboxylic acids (Figure 1b) by substituting the 6‐ or 7‐position of 2‐anthracenecarboxylic acid 2 a with bulky (6‐ t ‐Bu; 2 b ), electron‐donating (6‐MeO; 2 c ), [18] and electron‐withdrawing (7‐NO 2 ; 2 d ) groups. As the electron‐withdrawn type, we originally designed the 6‐substituted one (6‐NO 2 ; 2 d’ ).…”

“…So far, the photocyclodimerization of 2 a and its derivatives has been extensively studied, and the separation and quantification of the regio‐ and enantio‐isomers were well established based on the technique of high‐performance liquid chromatography (HPLC) [4–14] . Meanwhile, there has been one report on the photocyclodimerization of 2 c , where the regioisomers were separated by a preliminary method, i. e. by selective crystallization of a particular regioisomer [18] . In contrast, the photocyclodimerization of 2 b and 2 d has never been studied.…”