Photooxidation of oxazolidine molecular switches: uncovering an intramolecular ionization facilitated cyclization process

Abstract

Photooxidation of oxazoline (OXA) molecular switches through media-induced intramolecular ionization is reported. The formation of the photooxidation product occurs by attack of the flexible donor group (–CH₂CH₂OH) to the adjacent CC with ¹O₂ as the oxidant. The novel seven-membered ring sub-structure of the photooxidation product was inferred by HRMS, IR and ¹H NMR spectroscopy. Additionally, acid released from solvent photolysis was found to affect the product formation and efficiency of the photooxidation.