Benzofuran Derivatives. II. Synthesis of 2,3-Dihydrobenzofurans from Ethyl 2-Acylphenoxyacetates
作者:Tsuneo Suzuki
DOI:10.1246/bcsj.58.2821
日期:1985.10
and 3-hydroxyl groups are cis) were exclusively obtained in high yields. On the other hand, a nearly equimolecular amount of the cis and trans isomers was obtained from the reaction of 2-formyl derivatives under the same conditions.
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