Synthetic Studies on the Benzofuran Derivatives. II. Reactions of Aromatic o-Hydroxyaldehyde Derivatives and Ethyl Bromomalonate
作者:Takashi Matsumoto、Kenji Fukui
DOI:10.1246/bcsj.30.3
日期:1957.1
ne (V) and 2,2-dicarbethoxy-3-hydroxy-6-benzyloxycoumaran (XII) were synthesized respectively from 2,6-dihydroxy-3-carbomethoxybenzaldehyde (IV) or 4-benzyloxy-2-hydroxybenzaldehyde (X) and ethyl bromomalonate by the method of Tanaka for benzofuran synthesis. 2-Carbethoxy-4-hydroxy-5-carbomethoxycoumarone (V) was hydrolysed to 4-hydroxycoumarone-2,5-dicarboxylic acid (VI). This dibasic acid VI was
2-Carbethoxy-4-hydroxy-5-carbomethoxycoumarone (V) 和 2,2-dicarbethoxy-3-hydroxy-6-benzyloxycoumaran (XII) 分别由 2,6-dihydroxy-3-carbomethoxybenzaldehyde (IV) 或 4-苯甲氧基-2-羟基苯甲醛(X)和溴丙二酸乙酯通过Tanaka的方法合成苯并呋喃。2-Carbethoxy-4-hydroxy-5-carbomethoxycoumarone (V) 被水解成 4-hydroxycoumarone-2,5-二羧酸 (VI)。这种二元酸 VI 在喹啉中用铜粉脱羧成卡兰卓尔 (VIII) 和卡兰吉酸 (IX) 的混合物。2,2-Dicarbethoxy-3-hydroxy-6-benzyloxy-coumaran (XII) 被水解成 6-benzyloxycoumarone-2-