Benzofuran Derivatives. I. On the Effects of Substituents in Benzofuran Syntheses
作者:Tsuneo Suzuki、Takaaki Horaguchi、Takahachi Shimizu、Teishiro Abe
DOI:10.1246/bcsj.56.2762
日期:1983.9
of 4-substituted 2-acylphenoxyacetic acids give a mixture of benzofurans and 2-benzofurancarboxylic acids. The relative yields of benzofurans and 2-benzofurancarboxylic acids depend on the substituents on the benzene ring of the 2-acylphenoxyacetic acids. Electron-withdrawing substituents such as nitro groups favor the formation of 2-benzofurancarboxylic acids. On the other hand, the formation of benzofurans
4-取代的2-酰基苯氧基乙酸的Rossing反应得到苯并呋喃和2-苯并呋喃甲酸的混合物。苯并呋喃和 2-苯并呋喃甲酸的相对产率取决于 2-酰基苯氧乙酸苯环上的取代基。吸电子取代基如硝基有利于形成 2-苯并呋喃甲酸。另一方面,在 2-酰基-4-硝基苯氧乙酸与无水乙酸钠和乙酸酐的反应中,2-酰基的空间位阻有利于苯并呋喃的形成。