Study On Visible And Photocatalytic Reaction Of Three Kinds Of New Oxygen Particles

Molecular oxygen-participated visible-light photoredox reaction is regarded as one of green organic synthetic methods. This type of reaction is usually low catalyst loading and does not involve stoichiometric hazardous oxidants. So it is operationally simple and environmentally-friendly. In the dissertation, aerobic visible-light-mediated oxidation reactions are reviewed and our studies in this field are described.This dissertation is divided into four chapters.Chapter I. The introduction of recent development of aerobic visible-light-mediated oxidation reactions.Chapter II. A simple and efficient visible-light-promoted method for the C-3 thiocyanation of indoles. The transformation used an organic dye, Rose Bengal, as the photocatalyst and air as the terminal oxidant. The reaction is mild, high-yielding, and environmentally-benign.Chapter III. A metal-free visible-light-mediated nitroso Diels-Alder reaction. In this reaction, hydroxylamines were oxidized by molecular oxygen from air using Rose Bengal as catalyst under visible light irradiation. The in situ formed nitroso compounds underwent Diels-Alder reaction with dienes to afford oxazine derivatives. No heavy metal catalysts and hazardous stoichiometric oxidants were involved.Chapter IV. A visible-light-mediated aerobic oxidation of secondary enaminones by singlet oxygen. In this reaction, an unexpected 1,2-acyl migration occured to afford quaternary amino acid derivatives. Unlike the typically reported double bond cleavage by singlet oxygen to form two carbonyl compounds, this reaction is proposed to go through an ene-type pathway.