2,3-Diethoxydiphenyl Ether-5,4´-dicarboxylic Acidの合成

抄録

2, 3-Diethoxydiphenyl ether-5, 4′-dicarboxylic acid (VIII), m.p. 229-230°, and its dimethyl ester (VII), m.p. 72-73°, were prepared. The starting material for such synthesis, 3, 4-dimethoxy-6-bromobenzoic acid (III) or the corresponding diethoxy compound, when treated with hydrogen bromide and glacial acetic acid, undergoes dealkylation to form 3, 4-dihydroxy-6-bromobenzoic acid, as well as the transition of the bromine from 6- to 5-position and to form 3, 4-dihydroxy-5-bromobenzoic acid (IV).