Insights Into the Mechanism of Energy Transfer with Poly(Heptazine Imide)s in a Deoximation Reaction

Abstract

Abstract Following our previous studies on potassium poly(heptazine imide) (K‐PHI), that is, catalyzed photooxidative [3+2] aldoxime‐to‐nitrile addition to form 1,2,4‐oxadiazoles, we discovered that electron‐rich oximes yield the parent aldehydes instead of target products. In this work, the mechanism of this singlet oxygen‐mediated deoximation process was established using a series of control reactions and spectroscopic measurements such as steady‐state and time‐resolved fluorescence quenching experiments. Additionally, the singlet‐triplet energy gap value was obtained for K‐PHI in suspension, and the reaction scope was broadened to include ketoximes.