ぎ酸

解説CH2O2(46.03)．HCOOH．メタン酸ともいう．アリの蒸留ではじめて見いだされ，この名称がつけられた．少量ではあるが広く植物界(イラクサ，松葉，果実など)に分布する．天然にはアリのほかにイラクサなどの植物にも含まれていて、イラクサに触れると皮膚がひりひりするのはギ酸によるといわれている。分子内にカルボキシ基（カルボキシル基）とアルデヒド基の両方をもつので、酸性と還元性を持ち合わせている。酸性は酢酸よりはるかに強い。無色の刺激臭の液体．融点8.4 ℃，沸点100.8 ℃．d2041.220．n20D1.371．pKa 3.77．水との共沸混合物(沸点107.2 ℃)はギ酸77.4％ である．引火点68.9 ℃(開放式)．水，エタノール，エーテル，グリセリンなどに可溶．高濃度のギ酸は皮膚を腐食する．カルボン酸であると同時に，カルボキシル基に直接水素が結合しているため，アルデヒド的性質をもち還元性を示す．アンモニア性硝酸銀を銀に還元し，また過マンガン酸カリウムで容易に酸化される．合成原料，染色，ゴム工業などに用途がある．LD50 1100 mg/kg(ラット，経口)．森北出版「化学辞典（第2版）

用途Edman法によるアミノ酸配列分析用試薬。

用途悪臭物質の分析における試料又は標準物質の脱着、空試験用。

用途分析試薬、溶剤、有機合成原料等。脱灰剤としての用途もある。

用途無機及び有機化合物溶剤

用途有機合成原料、溶剤等。

用途染色助剤、皮なめし剤、医薬中間体原料、溶剤。中間物、洗剤等、繊維用添加剤、紙用添加剤、その他添加剤、電池、蓄電池、触媒。医薬·食品添加物などの中間体原料

用途HPLC用溶離液の調製、試料の前処理剤。

説明Formic acid is a clear, colorless liquid with a pungent odor. Formic acid was first isolated from certain ants and was named after the Latin formica, meaning ant. It is made by the action of sulfuric acid on sodium formate, which is produced from carbon monoxide and sodium hydroxide. It is also produced as a by-product in the manufacture of other chemicals such as acetic acid. It can be anticipated that use of formic acid will continuously increase as it replaces inorganic acids and has a potential role in new energy technology. Formic acid toxicity is of a special interest as the acid is the toxic metabolite of methanol.

天然物の起源Widespread in a large variety of plants; reported identifed in Cistus labdanum and the oil of Artemisia trans- iliensis; also found among the constituents of petit grain lemon and bitter orange essential oil; reported found in strawberry aroma Reported found in apple, sweet cherry, papaya, pear, raspberry, strawberry, peas, cheeses, breads, yogurt, milk, cream, buttermilk, raw fsh, cognac, rum, whiskey, cider, white wine, tea, coffee and roasted chicory root

来歴Formic acid is taken from the Latin word forant, formica. Naturalists had observed the acrid vapor from ant hills for hundreds of years. One of the earliest descriptions of formic acid was reported in an extract of a letter written from John Wray (1627–1705) to the publisher of Philosophical Transactions published in 1670. Wray’s letter reported on “uncommon Observations and Experiments made with an Acid Juyce to be Found in Ants” and noted the acid was previously obtained by Samuel Fisher from the dry distillation of wood ants. Formic acid is found in stinging insects, plants, unripe fruit, foods, and muscle tissue. Jns Jacob Berzelius (1779–1848) characterized formic acid in the early 19th century, and it wasfirst synthesized from hydrocyanic acid by Joseph Louis Gay-Lussac (1778–1850) at about the same time. A number of synthetic preparations of formic acid were found in the first half of the 19th century. Marcellin Berthelot (1827–1907) discovered a popular synthesis using oxalic acid and glycerin in 1856; he and several other chemists from his period found syntheses of formic acid by heating carbon monoxide in alkaline solutions.