Enhanced head-to-head photodimers in the photocyclodimerization of anthracenecarboxylic acid with a cationic pillar[6]arene

The complexation behaviors of anthracenecarboxylic acid and water-soluble cationic pillararenes have been investigated by 1H NMR, UV–vis and ITC methods. The cationic pillar[6]arene was found to stepwise form 1:1 and 1:2 complexes, having a large K1 and a relatively small K2 values. Photocyclodimerization of AC within the pillar[6]arene improved the yield of the head-to-head photodimers. Up to 4.97 HH/HT ratio has been reached by optimizing the reaction conditions.

Graphical abstractPhotocyclodimerization of anthracenecarboxylic acid within a cationic pillar[6]arene improved the yield of the head-to-head photodimers.Figure optionsDownload full-size imageDownload as PowerPoint slide