Ozone hydrotrioxide formation

Corey and coworkers have shown that trimethylsilyl hydrotrioxide, produced by the low-temperature (—78°C) ozonization of triethylsilane, decomposes at higher temperatures to give singlet oxygen. The formation of singlet oxygen was confirmed by the change in the IR emission at 1278 nm with time ( O2 2). ... 

The relationship between the conformation of the acetal function and its reactivity towards ozone has been described in detail (cf p. 41 ). It was shown that the insertion of ozone into the C —H bond of the acetal function to form the corresponding hydrotrioxide tetrahedral intermediate is subject to stereoelectronic control. This section deals with the next step of this reaction, i,e., the decomposition of the hydrotrioxide tetrahedral intermediate to yield the ester product. Experimental results will be presented to show that this step is also controlled by stereoelectronic effects. These results can therefore be used as evidence for the principle of stereoelectronic control in ester formation. 

Dioxin, M. Ebb, E. Ferments. Mir, Moscow, 1966, p. 277 Cerkovnik, J. , Eizen, E. Roller, J. Plesni ar, B. Evidence for HOOO. radicals in the formation of alkyl hydrotrioxides (ROOOH) and hydrogen trioxide (HOOOH) in the ozonation of C-H. bonds in hydrocarhons. Journal of the American Chemical SodetylQQl, 124(3), 404-409. Kamogitzkii, V. Organic Peroxides. IL, Moscow, 1961, p. 115. 

Preparative Methods addition of triethylsilane (2 equiv) to a cold (—78 °C), saturated methylene chloride solution of ozone (ca. 0.04 M) results in discharge of the color with formation of triethylsilyl hydrotrioxide within 45 s. ... 

Alkene Oxidation Reactions. The reaction of triethylsilane with ozone and use of the intermediate triethylsilyl hydrotrioxide in oxidation reactions have been described. Initial oxidation reactions reported included the formation of the 9,10-endoperoxide from 9,10-dimethylanthracene (eq 1), and an allyUc hydroperoxide from 2,3-dimethyl-2-butene (eq 2). Researchers also observed a near-IR emission from triethylsilyl hydrotrioxide as it decomposed at —60°C, consistent with generation of singlet oxygen. Other workers have characterized triethylsilyl hydrotrioxide by NMR spectroscopy and and measured the kinetics of its decomposition in deuterated acetone. ... 

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