ベンゾイルぎ酸 化学特性,用途語,生産方法
外観
白色～うすい黄色粉末～結晶
溶解性
エタノール、アセトン及び水に溶ける。
解説
C8H6O3(150.13)．C6H5COCOOH．ベンゾイルギ酸は，フェニルグリオキシル酸ともいう．アセトフェノンを酸化するか，ベンゼンにシュウ酸モノエステルクロリドをフリーデル-クラフツ縮合させたのち，加水分解するなどの方法でつくられる．結晶．融点66 ℃，沸点147～151 ℃(1.6 kPa)．水に易溶．濃硫酸により安息香酸とCOに分解する．森北出版「化学辞典（第2版）
用途
フェニルグリオキシル酸は、過マンガン酸カリウムによるマンデル酸の酸化によって合成できる。ベンゾイルシアニドの加水分解でも得られる。
用途
共役塩基は、ベンゾイルギ酸として知られ、チアミン二リン酸依存性酵素であるベンゾイルギ酸デカルボキシラーゼの基質となる。
用途
有機合成原料。
化学的特性
white to light yellow adhering crystals,
使用
Phenylglyoxylic Acid (cas# 611-73-4) is a compound useful in organic synthesis.
定義
ChEBI: A 2-oxo monocarboxylic acid that is glyoxylic acid in which the aldehyde hydrogen is substituted by a phenyl group.
安全性プロファイル
A poison by intravenous route. When heated to decomposition it emits acrid smoke and irritating vapors.
合成
The synthesis of Benzoylformic acid is as follows:Acetophenone (120 g, 1 mol) was dissolved in 2000 ml of pyridine, and 165 g (1.5 mol) of selenium dioxide was added under stirring.The mixture was refluxed for 3 hours and left to cool overnight.Filter through celite, wash the filter cake with xylene, and combine the filtrate and washings with azeotropic evaporation.The evaporated residue was dissolved in 1 L of ethyl acetate and washed with 300 ml of 10% dilute hydrochloric acid.The organic layer was washed with 400 ml of 5% sodium hydroxide solution, and the washed aqueous layer was adjusted to pH 2-3 with 10% dilute hydrochloric acid.A white solid precipitates, is filtered, the filter cake is washed with water, and dried to obtain 120 g of a white solid.Yield: 87%, purity: 99.2%.
純化方法
If the sample is oily, then it may contain H2O. In this case dry it in a vacuum desiccator over P2O5 or KOH until crisp. For further purification dissolve 5.5g in hot CCl4 (750mL), add charcoal (2g, this is necessary otherwise the acid may separate as an oil), filter, cool in ice-water until crystallisation is complete. Filter the acid off, and the solvent on the crystals is removed by keeping the acid (4.5g) in a vacuum desiccator for 2 days. Slightly yellow crystals are obtained. It can be recrystallised also from *C6H6/pet ether, and can be distilled in a vacuum. The acid is estimated by titration with standard NaOH. The phenylhydrazone is recrystallised from EtOH, m 163-164o, and the semicarbazone acid has m 259o(dec) (from EtOH). The methyl ester distils at 137o/14mm, 110-111o/2mm, n 20 1.5850. [Baert & Kates J Am Chem Soc 67 1482 1945, Schaffer & Corey J Org Chem 24 1825 1959, Beilstein 10 H 654, 10 IV 2737.]
ベンゾイルぎ酸 上流と下流の製品情報
原材料
準備製品