In 2003,Chan et al reported the epoxidation reaction of olefin catalyzed by MnSO in ionic liquids. The results showed that tetramethylammonium bicarbonate 4 must be substituted for sodium bicarbonate to have a satisfactory reaction effect. This is because sodium bicarbonate is insoluble in the ionic liquid used [bmim][BF], and the latter is not only easily soluble in it, but may also serve as a phase transfer catalyst.
Chemical wholesaler Ionic liquid [bmim][PF] is [hexafluorophosphate (1-butyl-3-methyl-imidazole) onium salt] is insoluble with water. When 6 it is combined with the water-soluble ionic liquid [bmim][BF] is tetrafluoroborate (1-butyl-3-methyl-imidazole) onium salt 4, not only epoxidation can occur, In addition, the products after the reaction are easier to be extracted and separated. [42]Bortolini et al. In the above two ionic liquids, 30% hydrogen peroxide can epoxidize the electron-deficient ketene substrates at room temperature under the catalysis of sodium hydroxide aqueous solution. It is found that the epoxidation rate is faster than the similar reaction in water, and no epoxy hydrolysis occurs. For α,β-[43] unsaturated cycloketones with more substituents, excessive oxidizing agents are required, and the reaction time needs to be prolonged. 3.7 Oxidation Reaction in supercritical Carbon dioxide Organic reaction in supercritical carbon dioxide is a hot topic in organic chemistry in recent years, and it is also an important content of green chemistry [44]. Eckert et al. studied in detail the chemical behavior of hydrogen peroxide in supercritical carbon dioxide and the epoxidation of cyclohexene and sodium 3-cyclohexene-1-carboxylate. In this chemical wholesaler epoxidation system, carbon dioxide is both the reaction medium and the reactant, and it can interact with hydrogen peroxide to form peroxycarbonic acid intermediates. It is found that the addition of bicarbonate is essential, which can affect the reaction balance of carbon dioxide and hydrogen peroxide and effectively increase the concentration of peroxybicarbonate ion, thereby increasing the yield of epoxide (Scheme 10). Beckman et al. also studied epoxidation in supercritical carbon dioxide (Scheme 10). It is found that the effect of adding proper concentration of sodium hydroxide is better than that of adding sodium bicarbonate. The yield of epoxide can be improved by adding surfactant or phase transfer catalyst. The resulting epoxide is then chemical wholesaler hydrolyzed to obtain diol. Chemical Encyclopedia Introduction and Index The Chemical Encyclopedia is a comprehensive and systematic introduction to the field of chemical engineering and chemical process knowledge, covering all aspects of chemical engineering, including principles, applications, equipment, processes and other content.
