Methyl Acetate

化学的特性Methyl acetate has a pleasant, fruity odor and slightly bitter flavor. May be prepared by boiling acetic acid and methanol in the presence of acid catalysts; or by heating methanol with an excess carbon monoxide under pressure in the presence of a catalyst (phosphoric acid, cobalt salts). Methyl acetate occurs naturally in low concentrations in mint, fungus,grapes, banana, coffee (Furia and Bellanca, 1975) and is a volatile constituent of nectarines (Takeoka et al., 1988). It is also present in some distilled alcoholic beverages (Shimoda et al., 1993). It is produced industrially via the carbonylation of methanol as a byproduct of acetic acid production or by esterification of acetic acid with methanol in the presence of strong acid such as sulfuric acid.

解説酢酸メチル メタノールと酢酸とを硫酸触媒の存在下で加熱すると得られる．果実の芳香をもつ無色の液体．融点－98 ℃，沸点56.9 ℃．0.9342．1.3614．引火点－10 ℃．水に可溶．エタノール（エチルアルコール）、エーテルなどの有機溶媒と任意の割合で混じり合うほか、水にもかなり溶ける。合成樹脂、ペイント、香料などの溶剤としての用途をもつ。

用途溶剤（香料、ニトロセルロース、合成樹脂、塗料他）

用途環境ホルモン物質であるアルキルフェノール類およびビスフェノールAを分析する際に、抽出溶媒として用いられます。

用途合成反応用溶剤、塗料?印刷インキ用溶剤、マニキュア、ラッカー、香料の溶剤

説明Methyl acetate, also known as MeOAc , acetic acid methyl ester or methyl ethanoate, is a carboxylate ester with the formula CH3COOCH3. It is a flammable liquid with a characteristically pleasant smell reminiscent of some glues and nail polish removers. Methyl acetate is occasionally used as a solvent, being weakly polar and lipophilic, but its close relative ethyl acetate is a more common solvent being less toxic and less soluble in water. Methyl acetate has a solubility of 25% in water at room temperature. At elevated temperature its solubility in water is much higher. Methyl acetate is not stable in the presence of strong aqueous bases or aqueous acids. Methyl acetate is VOC exempt.

天然物の起源Reported found in apple, banana, sweet and sour cherry, tangerine juice, black currants, guava, grapes, melon, peach, pear, pineapple, strawberry, cabbage, tomato, clove bud, peppermint oil, vinegar, bread, cheeses, butter, yogurt, beef, beer, cognac, rum, whiskies, cider, sherry, grape wines, cocoa, coffee, filbert, peanut, honey, soybean, olive, passion fruit, fruit brandies, fig, gin, kiwifruit, clary sage, arrack and nectarine.

使用Methyl acetate is used as a solvent forlacquers, resins, oils, and nitrocellulose; inpaint removers; as a flavoring agent; and inthe manufacture of artificial leather.

一般的な説明Methyl acetate appears as a clear colorless liquid with a fragrant odor. Moderately toxic. Flash point 14 °F. Vapors heavier than air.

製造方法Methyl acetate is produced industrially via the carbonylation of methanol as a byproduct of the production of acetic acid.Methyl acetate also arises by esterification of acetic acid with methanol in the presence of strong acids such as sulfuric acid, this production process is famous because of Eastman Kodak's intensified process using a reactive distillation. 2–1-Reactions In the presence of strong bases such as sodium hydroxide or strong acids such as hydrochloric acid or sulfuric acid it is hydrolyzed back into methanol and acetic acid, especially at elevated temperature. The conversion of methyl acetate back into its components, by an acid , is a first-order reaction with respect to the ester. The reaction of methyl acetate and a base, for example sodium hydroxide, is a second-order reaction with respect to both reactants. 3-Applications A major use of methyl acetate is as a volatile low toxicity solvent in glues, paints, and nail polish removers. Acetic anhydride is produced by carbonylation of methyl acetate in a process that was inspired by the Monsanto acetic acid synthesis.

純化方法Methanol in methyl acetate can be detected by measuring its solubility in water. At 20o, the solubility of methyl acetate in water is ca 35g per 100mL, but 1% MeOH confers complete miscibility. Methanol can be removed by conversion to methyl acetate, by refluxing for 6hours with acetic anhydride (85mL/L), followed by fractional distillation. Acidic impurities can be removed by shaking with anhydrous K2CO3 and distilling. An alternative treatment is with acetyl chloride, followed by washing with concentrated NaCl and drying with CaO or MgSO4. (Solid CaCl2 cannot be used because it forms a crystalline addition compound.) Distillation from copper stearate destroys peroxides. Free alcohol or acid can be eliminated from methyl acetate by shaking with strong aqueous Na2CO3 or K2CO3 (three times), then with aqueous 50% CaCl2 (three times), saturated aqueous NaCl (twice), drying with K2CO3 and distilling it from P2O5. [Beilstein 2 IV 122.]

定義本品は、酢酸とメタノールのエステルであり、次の化学式で表される。

定義ChEBI: Methyl acetate is an acetate ester resulting from the formal condensation of acetic acid with methanol. A low-boiling (57°C) colourless, flammable liquid, it is used as a solvent for many resins and oils. It has a role as a polar aprotic solvent, a fragrance and an EC 3.4.19.3 (pyroglutamyl-peptidase I) inhibitor. It is an acetate ester, a methyl ester and a volatile organic compound.