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The formation of dihydrogen trioxide (HOOOH) is reported as indeed the characteristic feature of the decomposition of various silyl as well as germyl hydrotrioxides, generated by the low-temperature ozonation of the corresponding silanes and germanes. Results of the detailed experimental and theoretical studies of the NMR and IR spectral characterization of the polyoxides under investigation as well as of the mechanism of their formation and decomposition are presented.

A thorough evaluation of the estimated power indicates that the gas-phase mechanism of the reaction is governed by radical or biradical mediators, whilst the solution-phase mechanism is distinguished by hydride transfer and the creation of a transitional ion pair which comprises of HOOO- anion. Finally, the amount of ozonation of alcohols and toxicity of ozone consumed in the blood can be determined.

The functioning of the sulfonic acid comprising of SBA-15 silica materials are evaluated as catalysts for the effect of compressing phenol and acetone to bisphenol A. It seems that a coordinated effort between the two close performing groups could be working in this reaction.

The ozonation of cumene in acetone, methyl acetate, and tert-butyl methyl ether at -70degree centigrade at low temperature produced the corresponding hydrotrioxide along with hydrogen trioxide, HOOOH. Ozonation of triphenylmethane produced only triphenylmethyl hydrotrioxide, (C6H5)3COOOH, which further supports the radical mechanism for the first step of ozonation of the C- H bonds in hydrocarbons.

Research has been conducted on the thianthrene 5-oxide. The oxidation of this oxide with peroxybenzoic acids has been investigated in different oxygen bases as solvents and the results are discussed.

Nuclear magnetic resonance spectrometry was done to study the kinetics of deiodination of o-iodocumyl alcohols by cyclohexyl radicals. The results revealed that the homolytic cleavage of the I-O bond in (tert-butylperoxy)iodanes with the formation of iodanyl (9-I-2) and tert-butylperoxyl radicals is the primary decomposition step. It was also indicated that the deiodination of o-iodocumyl alcohols by cyclohexyl radicals occurs via the SH2 type mechanism.

The role of water in the decomposition of hydrogen trioxide (HOOOH) on a singlet potential energy surface was investigated. Specifically, the quantum mechanics underpinning intramolecular 1,3-proton transfer in HOOOH was analyzed via ab initio self-consistent field calculations. The computations showed that the inclusion of water as a bifunctional catalyst lowered the energy barrier for the decomposition reaction.

The various mechanisms involved in the low temperature, methyltrioxohenium(VII)-catalyzed transformation of the hydrotrioxides (ROOOH) into dihydrogen trioxide (HOOOH) are discussed. The approach is shown to be extremely efficient and effective for a quantitative preparation of HOOH.

Various density functional methods were employed to study the hydrogen-bonded gas-phase molecular clusters of dihydrogen trioxide (HOOOH). The results obtained demonstrated that HOOOH could form relatively strong hydrogen-bonded cyclic dimers, trimers and tetramer with organic bases such as acetone and dimethyl ether and retard the decomposition in these bases as solvents by preventing a proton transfer.

The effect of ortho substituents in iodobenzenes on the rate of the abstraction of iodine by cyclohexyl radicals is examined. The stabilization of the transition state, resembling a 9-I-2 iodanyl radical, by electron-withdrawing groups describes a positive sign of the Hammett rho value in the radical abstraction of halogen atoms.

Ozonation of norcarane (1) yielded endo and exo norcarane hydrotrioxides(2a, 2b), which is characterized by 1H and 13C NMR spectroscopy. The main focus of intense investigations is on Hydrogen trioxide (HOOOH) and its organic derivatives, that is, alkyl hydrotrioxides (ROOOH).

The ozonation of 1,2-diphenylhydrazine and 1,2-dimethylhydrazine is examined. The abstraction of a methyl H atom of the Ch3NNHCh3 radical by HOOO in the solvent cage results in the formation of formic acid and nitromethane in the ozonolysis of 1,2-dimethylhydrazine.

H atom (HO(sub 3)(super -)) formation by using dioxolanes as suitable model systems that support hydride abstraction by ozone due to the fact that generation of a dioxolyl cation is electronically supported, is studied. The low-temperature ozonation of 2-methyl-1,3-dioxolane in an acetone-d(sub 6), methyl acetate, and tert-butyl methyl ether produced both the corresponding acetal hydrotrioxide ROOOH and the hemiortho ester in molar ratio 1:5 (-78 degree C) is reported.

The HOOO(super -) anion, which can adopt a triplet state (T-1) or a singlet state (S-1), where the former was 9.8 kcal/mol (delta H(298) = 10.3 kcal/mol), which was more stable than the later is reported. The modes of generating S-1 in aqueous solution was discussed, which shows that S-1 represents an important intermediate in ozonation reactions.

The hydrotioxide of isopropyl alcohol and hydrogen trioxide (HOOOH) were observed to form in the low-temperature ozonation of the alcohol. Both polyoxides were characterized for the first time by 17O nuclear magnetic resonance spectroscopy. Results elucidated on the transition structure for the ozonation of isopropyl alcohol. Also, it showed the role of radical intermediates in the reaction.

Ozonation of 2-ethylanthrahydroquinone with an ozone-nitrogen or ozone-oxygen mixture in acetone-d6 and methyl acetate at -78 degrees Celsius generated an oxygen-rich intermediate with a characteristic OOOH absorption. This was used to find new ways to synthesize and characterize hydrogen trioxide (HOOOH). The oxidation of anthrahydroquinone by using ozone rather than oxygen provides HOOOH and the associated quinone as the primary products.

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