Unsymmetrical anthracene derivatives have been synthetized and demonstrated a good ability to capture, store and release singlet oxygen (¹O₂). Kinetic studies performed by UV-visible spectroscopy revealed the influence of the substituents on the photooxygenation and the thermal cycloreversion steps. These derivatives appeared as promising ¹O₂ batteries for dark photooxygenation.

Abstract

Aromatic architectures able to capture, store and release singlet oxygen have sparked the interest of the scientific community as an attractive strategy to generate singlet oxygen. Among these structures, anthracenes are efficient singlet oxygen batteries with applications in various fields such as chemistry, materials science or medicine. Until now, studies have mainly focused on symmetrical 9,10-disubstituted anthracenes bearing (hetero)aryl groups or substituted alkyne motifs. In this work, we investigated unsymmetrical anthracene molecules to explore their propensity to trap and to release singlet oxygen. Kinetic studies confirmed the impact of electron-rich and electron-deficient substituents on the photooxygenation step and on the release of singlet oxygen triggered by thermolysis of the endoperoxides.