Development of Electro Recyclable System by Use of Ruthenium Compound as a Redox Reagent

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A practically viable procedure for the oxidation of 1, 2 ; 5, 6-0-indirect isopropylidene-alpha-D-glucofuranose to the corresponding ulose has been developed by using the indriect electrooxidation method with two redox couples of RuO_4/RuO_2 and [Cl^+]/Cl^-. The conditions were optimized as follows : an aqueous phase at pH ca. 10 ; a mixture of carbon tetrachloride and tert-butyl alcohol (ca. 9 : 1 v/v) as an organic phase ; current densities at 10-40 mA/cm^2 ; temperature at 20-40 ^0 ; the use of 2 mol% of RuO_2.2H_2O. Thus, the electrolysis under the above conditions afforded the desired ulose in 90% yield. The method was successfully applied to a facile synthesis of isopropyl 3-amino-4-cyclohexyl-2-hydroxybutanoate from D-glucose diacetonide with chiral integrity of the C (4), C (5) carbons.The synthesis of 1, 3-dichloroacetone which is one of the most important synthetic intermediates in the production of N^2-sulfamoyl-3- [[(2-guanidino-4-thiazolyl) methyl] thio] -propionamidine (a … More histamine H_2 recepter) was investigated. The conditions for the indirect electrooxidation of 1, 3-dichloro-2-propanol were optimized in detail by examining various factors. Thus, the electrolysis of 1, 3-dichloro-2-propanol was carried out in an AcOEt-aqueous NaCl (2 : 3 V/V) system buffered at pH 3-4 in a divided cell as 0-5 ^OC, giving the desired ketone in 96% yield and, consequently, hence the formation of 1, 1, 3-trichloroacetone was suppressed to less than 1%. The method has proven to be useful for the oxidation of cyclohexane-1, 4-diol to cyclohexane-1, 4-dione, an important intermediate for electronics material such as TCNQ.In conclusion, as a result of the present Developmental Scientific Research, the ruthenium mediated indirect electrooxidation method can be extended, in a preparative scale, to the oxidation of a variety of alcohols including halohydrins and carbohydrates through making a proper choice of various factors, in particular, an electrolysis cell, pH value, and electrolysis medium. Less