P10 超音波照射によるマレイン酸とフマル酸の相互異性化

抄録

In this paper, we demonstrate the isomerization of unsaturated dicarboxylic acids during sonication. Almost all trials were carried out under irradiation of 200 kHz, 200W. Before sonication, pure argon gas (Ar) was passed through the reactant solution in order to expel the air. Concentrations and volumes of trial samples were 8-10 mM and 30-100 cm^3, respectively. Fumaric acid and maleic acid made isomerization under sonication each other. Because of obtaining similar amounts of CO and CO_2 each other, cleavage of reactants occurred and reactivities of both acids would almost the same. Higher stability trans type had higher yield, namely fumaric acid. So far, isomerization under ultrasonic irradiation was shown. However, additives were needed for isomerizaiton in those reports. In our system, on the other hand, isomerization occurred without additives. We also demonstrated dehydrogenation and forming double bond. In the case of sonolysis of succinic acid, unsaturated dicarboxylic acids were detected; those are fumaric acid and maleic acid. They are isomer each other and the carbon number of them are the same as succinic acid, namely 4. Succinic acid could be produced from acetic acid under sonication as reported Poster presentation (P-9) in this conference. Thus, continuous reactions under ultrasonic irradiation; those are carbon chain elongation from acetic acid, dehydrogenation from succinic acid and isomerization of their products might occur.