Singlet oxygen dioxirane

Sauter, M. and Adam, W. (1995) Oxyfunctionalization of benzofurans by singlet oxygen, dioxiranes, and peracids chemical model studies for the DNA-damaging activity of benzofuran dioxetanes (oxidation) and epoxides (alkylation). Accounts of Chemical Research, 28 (7), 289-298. 

Also, potassium superoxide (KO2) decomposes DMD in acetone solution to release singlet oxygen, as has been detected by the characteristic infrared chemiluminescence . Furthermore, a catalytic amount of n-Bu4NI decomposes TFD into oxygen gas and triflu-oroacetone in high yield . Analogous to the Caroate decomposition by ketones, also the catalytic decomposition of peroxynitrite by ketones, e.g. methyl pyruvate, is rationahzed in terms of peroxynitrite oxidation by in-situ-generated dioxirane. ... 

Singlet oxygen reacts with binaphthylphosphine derivatives such as 1, l -binaphthyldi-/-butylphosphine to form the corresponding binaphthyl-2-oxide phosphine oxides. This intramolecular arene epoxidation reaction proceeds with complete retention of stereochemistry. The binaphthyl-2-oxide di-/-butylphosphine oxide undergoes a slow NIH rearrangement to form the corresponding hydroxylated product. A transient phospha-dioxirane intermediate has been directly observed by low-temperature NMR.241... 

Adam, W. Ahrweiler, M. Sauter, M. Schmiedeskamp, B. Oxidation of indoles by singlet oxygen and dimethyl-dioxirane isolation of indole dioxanes and epoxides by stabilization through nitrogen acylation. Tetrahedron Lett. 1993, 34, 5247-5250. 

ON THE ROLE OF THE SINGLET-OXYGEN DIMOL CHEMILUMINESCENCE IN DIOXIRANE REACTIONS... 

Dioxiranes, three-membered-ring cyclic peroxides, are known as highly efficient and selective oxidants, capable of performing a variety of transformations for synthetic purposes. It is known that some reactions of these peroxides are accompanied by chemiluminescence due to the release of singlet oxygen. For instance, infra-red chemiluminescence (IR-CL) of O2 at A, 1270 nm is emitted in the reaction of tertiary amines and N-oxides with dimethyldioxirane (DMD) and methyl(trifluoromethyl)dioxirane (TFD), as well as during the anion-catalyzed breakdown of the dioxiranes. Furthermore, IR-CL emission is produced in the ketone-catalyzed decomposition of the monoperoxysulfate ion HSOs through the intermediary dioxirane. ... 

Singlet Oxygen Dimol Chemiluminescence in Dioxirane Reactions... 

Ferrer M, Sanchez-Baeza F, Messeguer A, Adam W, Golsch D, GOrth F, Kiefer W, Nagel V. The release of singlet oxygen in the reaction of dioxiranes with amine N-oxides. Eur J Org Chem 1998 2527-32 ... 

Adam W, Kazakov DV, Kazakov VP, Kiefer W, Latypova RR, Schlucker S. Singlet-oxygen generation in the catalytic reaction of dioxiranes with nucleophilic anions. Photochem Photobiol Sci 2004 3 182-8. 

Lange A, Brauer HD. On the formation of dioxiranes and of singlet oxygen by the ketone-catalysed decomposition of Caro s acid. J Chem Soc, Perkin Trans 2 1996 805-11. 

Dihydroxylation of benzofuran and benzothiophene giving d5 -2,3-dihydro-2,3-dihydroxy derivatives can be achieved nsing Pseudomonas putida. Benzofurans can be epoxidised at the hetero-ring double bond with dimethyl dioxirane, or alternatively converted into dioxetanes by reaction of that double bond with singlet oxygen. Both oxidised species are unstable and undergo a variety of complex further processes. ... 

Treatment of TMDO (54) with trimethylamine oxide or nucleophilic anions results in the formation of singlet oxygen. Chloride ion, for example, is first oxidized to hypochlorite ion, which then attacks another molecule of the dioxirane. Fragmentation ensues, producing trifluoroacetone, singlet oxygen, and regenerated chloride ion. 

Silylenes 1 are highly reactive homologues of the carbenes, and we have been interested to compare the reactivity and primary products of the oxidation of these divalent species. In principal one can expect two different primary adducts of a silylene and molecular oxygen the formal "end-on" adducts silanone 0-oxide 2 or "side-on" adducts dioxasilirane 3 (Scheme 1). It was shown by numerous matrix studies [8-12], experiments in solution using time resolved spectroscopy [13-16], and a preparative scale synthesis in solution [17] that triplet as well as singlet carbenes yield carbonyl 0-oxides as the primary oxidation products, while dioxiranes are products of secondary photolysis. Ando et al. reported on the synthesis of the silanone 0-oxide 2e by the reaction of dimesitylsilylene le and O2 in solid argon [1]. This is so far the only experimental evidence for a silanone O-oxide. 

A number of reactions including only first- and second-row atoms have also been studied. Some illustrative examples are the intramolecular transformation of methylene peroxide to dioxirane the photolytic decomposition of oxathiirane the reaction of singlet molecular oxygen with ethene and the dissociation of diimide . 

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