Photochemistry of trimethylene oxide and trimethylene sulfide radical cations in freonic matrices at 77 K

Abstract

It was shown that trimethylene oxide (oxetane) radical cations were converted at 77 K into either distonic radical cations ·CH2CH2CH=OH+ or 2-oxetanyl radicals, depending on the freonic matrix used, by the action of light at λ = 546 nm and trimethylene sulfide radical cations transformed into distonic radical cations CH2CHSH+CH2· under 436-nm irradiation. The quantum yields of the photochemical reactions were determined. Quantum-chemical calculations on the structure and HFC constants of the radical cations and possible paramagnetic products of their transformation were performed. The reasons behind the observed difference in reactivity between the radical cations under the action of light are discussed.