溶融金属カリウムを用いる夕張炭の還元的アルキル化反応における添加物効果

Abstract

Effects of additives, such as 18-crown-6 and potassium iodide, on improv-ed reductive alkylation of coal were investigated, where coal anion was prepared by molten potassium metal under refluxing tetrahydrofuran. Extent of anionization was affected by the ad-ditives at 0.5 h of anionization period, while little influence was observed at 2 h. Addition of 18-crown-6 to the solvent accelerated the reaction at 0.5 h. Ethylated Yubari coal, thus obtained, contained about 6 ethyl groups per 100 carbon atoms, 69wt% of which was solubilized in benzene. On the other hand, addition of potassium iodide decelerated the reaction. These obser-vations may result from acceleration and deceleration of formation of solvated electrons by the respective additives. Structural parameters of benzene soluble materials form the ethylated coals and results of reductive alkylation of diphenyl ether indicate that presence of the crown ether enhance the alkylation reaction at aromatic nuclei whereas presence of the potassium iodide cause relatively preferential ether cleavage.