| 摘要 |
PURPOSE:To suppress the formation of by-products and obtain an acetylbiphenylcarboxylic acid in high selectivity and good yield by oxidizing a readily available ethylbiphenyl compound in the presence of a catalyst containing cobalt and bromine in a solvent containing a lower aliphatic monocarboxylic acid. CONSTITUTION:An ethylbiphenyl compound expressed by formula I (R is methyl or ethyl) is oxidized with molecular oxygen in the presence of a catalyst containing cobalt and bromine in a solvent containing a lower aliphatic monocarboxylic acid such as formic, acetic or propionic acid to afford an acetylbiphenylcarboxylic acid expressed by formula II. The formation of a biphenyldicarboxylic acid which is a by-product can be suppressed according to this method. Although the cobalt in the catalyst may be used as a simple metallic substance, an organic acid salt of the lower aliphatic monocarboxylic acid used as the solvent is especially preferred. Molecular bromine or hydrogen bromide, sodium bromide, etc., are preferably used as the bromine in the catalyst. The acetylbiphenylcarboxylic acid expressed by formula II is useful as an intermediate for liquid crystal compounds or an intermediate raw material for highly functional polymers. |
