Photooxidation of Hantzsch 1,4-dihydropyridines by molecular oxygen
Photooxidation of Hantzsch 1,4-dihydropyridines (1,4-DHP, 1a–1d) by direct irradiation (λ > 300 nm) under an oxygen atmosphere has been carefully examined in this work. Spectroscopic and electrochemical studies demonstrate that photoinduced singlet electron transfer from 1,4-DHP to molecular oxygen occurs. The generated superoxide radical anion (O2 −·) is responsible for this typical photochemical oxidation.
KeywordsHantzsch 1,4-dihydropyridines molecular oxygen photoinduced electron transfer superoxide (O2−·)
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