endo/exo Isomerism in Norcarane and 2-Norcaranol Hydrotrioxides (ROOOH)

Abstract

Ozonation of norcarane (1) yielded endo and exo norcarane hydrotrioxides (2a, 2b), as characterized by (1)H and (13)C NMR spectroscopy. Further ozonation of the primary decomposition products of these hydrotrioxides, i.e., 2-norcaranols (3), produced the corresponding isomeric 2-norcaranol hydrotrioxides (4a, 4b), and hydrogen trioxide (HOOOH).

Recent Advances in the Chemistry of Hydrogen Trioxide (HOOOH)

“…Similarly, experimental observations made by studying the low-temperature ozonation of 2-ethylanthrahydroquinone, cumene, norcaranol, tetraline, α-methylbenzyl alcohol, and methyl α-methylbenzyl ether support the radical mechanism for formation of HOOOH.…”

“…In the last four decades, ozonations of several saturated organic compounds with activated C–H bonds, that is, alcohols, ethers, acetals, and some hydrocarbons as well, were studied in various organic solvents . Surprisingly, in recent years some of these compounds2-ethylanthrahydroquinone, isopropyl alcohol, , isopropyl methyl ether, cumene, norcaranol, tetraline, α-methylbenzyl alcohol, methyl α-methylbenzyl ether, and hydrazines , were found to react with ozone as reducing agents (AH 2 ) at low temperatures to form, among other products, hydrogen trioxide (HOOOH) as a metastable intermediate (eq ). AH 2 + normalO 3 → HOOOH + normalA …”

A Singlet Oxygen Priming Mechanism: Disentangling of Photooxidative and Downstream Dark Effects

“…A previous DFT study has identified the low-energy dimerization behavior of peroxyl radicals to hydrotrioxide with a 12.3 kcal/mol saddle point. Avzyanova et al and Plesničar et al , have reported the synthesis of organic hydrotrioxides, which like other peroxide decomposition can be accompanied by 1 O 2 formation. , Paths C and E: the Hock rearrangement can arise by a proton transfer to 2 and 3 , leading to water adducts 2 (+H + ) and 3 (+H + ). The conversion of 3 (+H + ) to cation 12 and water would lead to the 3° hydroperoxide rearrangement, which is easier than the 2° hydroperoxide rearrangement.…”

H2O3 as a Reactive Oxygen Species: Formation of 8-Oxoguanine from Its Reaction with Guanine

“…Giguere and co-workers , were the first who presented evidence for the existence of H 2 O 3 from IR and Raman spectra of an electrically dissociated mixture of water, hydrogen peroxide, and oxygen. It has been found that ozonation of several compounds, for example, 1,2-diphenylhydrazine, 2-ethylanthrahydroquinone, isopropyl alcohol, isopropyl methyl ether, and cumine in various organic solvents at low temperatures produces H 2 O 3 in large amounts. − Engdahl and Nelander showed that a significant amount of H 2 O 3 can be produced by photolyzing the ozone−hydrogen peroxide mixture in argon matrixes and established the IR spectroscopic identification for it . Nyffleler et al showed that significant amounts of H 2 O 3 produced in thermal reactions of H 2 O 2 and oxygen could be detected using 1 H NMR spectroscopy.…”