Y. Kawase, Matsuko Takashima
May 1, 1967
Citations
0
Influential Citations
6
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
Acetyl derivatives of 2, 3-dimethylbenzofuran and their methyl homologs were derived into the corresponding carboxylic acids by the haloform reaction, and the acetylation of thier esters by the Friedel-Crafts reaction was studied. The keto-esters obtained were hydrolyzed to give keto-acids, which were then further oxidized into dicarboxylic acids by the haloform reaction and decarboxylated to acetylbenzofurans. On the other hand, the dicarboxylic acids were also obtained by the oxidation of diacetylbenzofurans. By the haloform reaction of hindered acetyl compounds, we obtained only halogenated ketones, which it was difficult to hydrolyze to give carboxylic acids. After the structures of these products had been determined and compared, it became clear that the acetylation of 5-alkoxycarbonyl-2, 3-dimethylbenzofurans furnished the 6-acetylated compounds, while that of 6-alkoxycarbonyl compounds and their methyl homologs furnished the 4-acetylated compounds.