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چکیده
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Gem-dihydroperoxides (DHPs) that are important intermediates in synthesis of a number of classes of peroxides including tetraoxanes, silateraoxans, spirobisperoxyketals, bisperoxyketals, and 1,2,4,5- tetraoxacycloalkanes [1] stable derivatives of ketones and aldehydes [2]. These compounds have been of considerable interest because of their relevance to peroxidic antimalarial drugs [3]. On the other hand, Gem-dihydroperoxides have also been employed as reagents for oxidation reactions such epoxidation of a,ß-unsaturated ketones, enantioselective oxidation of 2-substituted 1,4-naphtoquinones and oxidation of sulfides [4]. because importance of these compounds, some methods have been reported to synthesis of gem-dihydroperoxides, but unfortunately, many of these methods have certain drawbacks including the use of concentrated H2O2 and excess acid, low yield, limited substrate range and production of mixtures of peroxidic products. Also, poor selectivity and the presence of ozone sensitive groups in the substrates are further limitations in ozonolysis reaction. Therefore, we wish to introduce the zirconium tetrachloride as a low-cost, new and effective catalyst for synthesis of gem-dihydroperoxides from ketones and aldehydes with 30% aqueous H2O2 at room temperature (Scheme 1). A variety of aldehydes and ketones have been converted to corresponding gem-dihydroperoxides by this method in excellent yields.
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