Murray and Jeyaraman

Dioxirane chemistry is well documented . Extensive kinetic, stereochemical and 0-labeling data suggested that dimethyldioxirane is the oxygen-atom transfer reagent in the Oxone-acetone system . Murray and Jeyaraman have shown that dialkyl dioxiranes can be isolated by low-temperature distillation from the reaction mixture of oxone and ketone . 

Dioxirane (RR C02) compounds are relatively new in the arsenal of the synthetic chemist, however since the isolation of dimethyldioxirane by Murray and Jeyaraman in 1985,146 it has become a very important oxidant for preparative oxygen transfer chemistry.147 The dioxiranes are ideal oxidants in that they are efficient in their oxygen atom transfer, exhibit high chemio- and regio-selectivities, act catalytically, are mild towards the substrate and oxidized product, and perform under strictly neutral conditions. The compounds are prepared from peroxymonosulfate and ketones under neutral to mildly alkaline conditions (Figure 2.46). 

Since its isolation in 1985 by Murray and Jeyaraman [2], dimethyldioxirane (DMD), as acetone solutions, has become a very important oxidant for preparative oxidation chemistry [3]. This novel three-membered ring cyclic peroxide constitutes an ideal oxidant in that it is efficient in its oxygen atom transfer, exhibits high chemo- and regioselectivity, acts catalytically, is mild towards the substrate and oxidized product, performs under strictly neutral conditions, and can be conveniently prepared from readily available commercial materials (Table 1). Dimethyldioxirane is prepared from the reaction of acetone with caroate [Eq. (1)] under buffered conditions and subsequently isolated by distillation in the form... 

The system developed by Edwards and Curci to generate dimethyl-dioxirane in situ has been modified by Murray and Jeyaraman to allow the distillation of a number of dioxiranes (12) as solutions, thus allowing spectroscopic characterization and a study of their chemical properties. 

The synthetically most useful method for the preparation of dioxiranes is the reaction of appropriate ketones (acetone, trill uoroacetone, 2-butanone, cyclohexanone etc.) with Caroate, commercially available as the triple salt of potassium monoperoxysul-fate (KHSOs). The catalytic cycle of the dioxirane formation and oxidation is shown in Scheme 1 in general form. For acetone as the ketone, by simple distillation at a slightly reduced pressure ca 100 torr) at room temperature ca 20 °C), Jeyaraman and Murray successfully isolated dimethyldioxirane (DMD) as a pale yellow solution in acetone (maximally ca 0.1 M). This pivotal achievement in 1985 fomented the subsequent intensive research activity in dioxirane chemistry, mainly the synthetic applications but also the mechanistic and theoretical aspects. The more reactive (up to a thousandfold ) fluorinated dioxirane, methyl(trifluoromethyl)dioxirane (TFD), was later isolated in a similar manner by Curd, Mello and coworkers". For dioxirane derived from less volatile ketones, e.g. cyclohexanone, the salting-out technique has been developed by Murray and coworkers to obtain the corresponding dioxirane solution. 

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