Methyl acetate

Last updated
Methyl acetate [1]
Methyl acetate.svg
Methyl acetate 3D ball.png
Names
Preferred IUPAC name
Methyl acetate
Systematic IUPAC name
Methyl ethanoate
Other names
Methyl ester of acetic acid
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.001.078
KEGG
PubChem CID
UNII
Properties
C3H6O2
Molar mass 74.079 g·mol−1
AppearanceColorless liquid
Odor Fragrant, fruity [2]
Density 0.932 g cm−3
Melting point −98 °C (−144 °F; 175 K)
Boiling point 56.9 °C (134.4 °F; 330.0 K)
~25% (20 °C)
Vapor pressure 173 mmHg (20°C) [2]
-42.60·10−6 cm3/mol
1.361
Hazards
Safety data sheet External MSDS
NFPA 704
Flammability code 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g., gasolineHealth code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentineReactivity (yellow): no hazard codeSpecial hazards (white): no codeMethyl acetate
3
1
Flash point −10 °C; 14 °F; 263 K [2]
Explosive limits 3.1%-16% [2]
Lethal dose or concentration (LD, LC):
3700 mg/kg (oral, rabbit) [3]
11,039 ppm (mouse, 4 hr)
21,753 ppm (cat, 1 hr)
32,000 ppm (rat, 4 hr) [3]
US health exposure limits (NIOSH):
PEL (Permissible)
TWA 200 ppm (610 mg/m3) [2]
REL (Recommended)
TWA 200 ppm (610 mg/m3) ST 250 ppm (760 mg/m3) [2]
IDLH (Immediate danger)
3100 ppm [2]
Related compounds
Related esters
Methyl formate
Ethyl acetate
Methyl fluoroacetate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

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 not considered as a VOC in the USA. [4] [5]

Ester chemical compounds consisting of a carbonyl adjacent to an ether linkage

In chemistry, an ester is a chemical compound derived from an acid in which at least one –OH (hydroxyl) group is replaced by an –O–alkyl (alkoxy) group. Usually, esters are derived from a carboxylic acid and an alcohol. Glycerides, which are fatty acid esters of glycerol, are important esters in biology, being one of the main classes of lipids, and making up the bulk of animal fats and vegetable oils. Esters with low molecular weight are commonly used as fragrances and found in essential oils and pheromones. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties, while polyesters are important plastics, with monomers linked by ester moieties. Esters usually have a sweet smell and are considered high-quality solvents for a broad array of plastics, plasticizers, resins, and lacquers. They are also one of the largest classes of synthetic lubricants on the commercial market.

Solvent substance that dissolves a solute (a chemically different liquid, solid or gas), resulting in a solution

A solvent is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Common uses for organic solvents are in dry cleaning, as paint thinners, as nail polish removers and glue solvents, in spot removers, in detergents and in perfumes (ethanol). Water is a solvent for polar molecules and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within a cell. Solvents find various applications in chemical, pharmaceutical, oil, and gas industries, including in chemical syntheses and purification processes.

Ethyl acetate chemical compound

Ethyl acetate is the organic compound with the formula CH
3
–COO–CH
2
–CH
3
, simplified to C
4
H
8
O
2
. This colorless liquid has a characteristic sweet smell and is used in glues, nail polish removers, decaffeinating tea and coffee. Ethyl acetate is the ester of ethanol and acetic acid; it is manufactured on a large scale for use as a solvent. The combined annual production in 1985 of Japan, North America, and Europe was about 400,000 tonnes. In 2004, an estimated 1.3 million tonnes were produced worldwide.

Contents

Preparation and reactions

Methyl acetate is produced industrially via the carbonylation of methanol as a byproduct of the production of acetic acid. [6] 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.

Carbonylation refers to reactions that introduce carbon monoxide into organic and inorganic substrates. Carbon monoxide is abundantly available and conveniently reactive, so it is widely used as a reactant in industrial chemistry. The term carbonylation also refers to oxidation of protein side chains.

Methanol, also known as methyl alcohol among others, is a chemical with the formula CH3OH (a methyl group linked to a hydroxyl group, often abbreviated MeOH). Methanol acquired the name wood alcohol because it was once produced chiefly by the destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide.

Acetic acid A colourless liquid organic compound found in vinegar

Acetic acid, systematically named ethanoic acid, is a colourless liquid organic compound with the chemical formula CH3COOH (also written as CH3CO2H or C2H4O2). When undiluted, it is sometimes called glacial acetic acid. Vinegar is no less than 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water. Acetic acid has a distinctive sour taste and pungent smell. In addition to household vinegar, it is mainly produced as a precursor to polyvinyl acetate and cellulose acetate. It is classified as a weak acid since it only partially dissociates in solution, but concentrated acetic acid is corrosive and can attack the skin.

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.

Sodium hydroxide chemical compound

Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations Na+
and hydroxide anions OH
.

Hydrochloric acid strong mineral acid

Hydrochloric acid or muriatic acid is a colorless inorganic chemical system with the formula H
2
O:HCl
. Hydrochloric acid has a distinctive pungent smell. It is classified as strongly acidic and can attack the skin over a wide composition range, since the hydrogen chloride completely dissociates in aqueous solution.

Hydrolysis is a term used for both an electro-chemical process and a biological one. The hydrolysis of water is the separation of water molecules into hydrogen and oxygen atoms using electricity (electrolysis).

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. [7]

Acetic anhydride chemical compound

Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula (CH3CO)2O. Commonly abbreviated Ac2O, it is the simplest isolable anhydride of a carboxylic acid and is widely used as a reagent in organic synthesis. It is a colorless liquid that smells strongly of acetic acid, which is formed by its reaction with moisture in the air.

The Monsanto process is an industrial method for the manufacture of acetic acid by catalytic carbonylation of methanol. The Monsanto process has largely been supplanted by the Cativa process, a similar iridium-based process developed by BP Chemicals Ltd which is more economical and environmentally friendly.

See also

Related Research Articles

Carboxylic acid oxoacid having the structure RC(=O)OH, used as a suffix in systematic name formation to denote the –C(=O)OH group including its carbon atom

A carboxylic acid is an organic compound that contains a carboxyl group. The general formula of a carboxylic acid is R–COOH, with R referring to the rest of the molecule. Carboxylic acids occur widely. Important examples include the amino acids and acetic acid. Deprotonation of a carboxyl group gives a carboxylate anion. Important carboxylate salts are soaps.

Formic acid chemical compound

Formic acid, systematically named methanoic acid, is the simplest carboxylic acid. The chemical formula is HCOOH or HCO2H. It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. The word "formic" comes from the Latin word for ant, formica, referring to its early isolation by the distillation of ant bodies. Esters, salts, and the anion derived from formic acid are called formates. Industrially formic acid is produced from methanol.

Fischer–Speier esterification

Fischer esterification or Fischer–Speier esterification is a special type of esterification by refluxing a carboxylic acid and an alcohol in the presence of an acid catalyst. The reaction was first described by Emil Fischer and Arthur Speier in 1895. Most carboxylic acids are suitable for the reaction, but the alcohol should generally be a primary or secondary alkyl. Tertiary alcohols are prone to elimination. Contrary to common misconception found in organic chemistry textbooks, phenols can also be esterified to give good to near quantitative yield of products. Commonly used catalysts for a Fischer esterification include sulfuric acid, tosylic acid, and Lewis acids such as scandium(III) triflate. For more valuable or sensitive substrates, dicyclohexylcarbodiimide is often used. The reaction is often carried out without a solvent or in a non-polar solvent to facilitate the Dean-Stark method. Typical reaction times vary from 1–10 hours at temperatures of 60-110 °C.

Cinnamic acid chemical compound

Cinnamic acid is an organic compound with the formula C6H5CH=CHCOOH. It is a white crystalline compound that is slightly soluble in water, and freely soluble in many organic solvents. Classified as an unsaturated carboxylic acid, it occurs naturally in a number of plants. It exists as both a cis and a trans isomer, although the latter is more common.

Cellulose triacetate chemical compound

Cellulose triacetate, is a chemical compound produced from cellulose and a source of acetate esters, typically acetic anhydride. Triacetate is commonly used for the creation of fibres and film base. It is chemically similar to cellulose acetate. Its distinguishing characteristic is that in triacetate, at least "92 percent of the hydroxyl groups are acetylated." During the manufacture of triacetate, the cellulose is completely acetylated; whereas in normal cellulose acetate or cellulose diacetate, it is only partially acetylated. Triacetate is significantly more heat resistant than cellulose acetate.

Organic acid anhydride any chemical compound having two acyl groups bonded to the same oxygen atom

An organic acid anhydride is an acid anhydride that is an organic compound. An acid anhydride is a compound that has two acyl groups bonded to the same oxygen atom. A common type of organic acid anhydride is a carboxylic anhydride, where the parent acid is a carboxylic acid, the formula of the anhydride being (RC(O))2O. Symmetrical acid anhydrides of this type are named by replacing the word acid in the name of the parent carboxylic acid by the word anhydride. Thus, (CH3CO)2O is called acetic anhydride. Mixed (or unsymmetrical) acid anhydrides, such as acetic formic anhydride (see below), are known.

Isoamyl acetate chemical compound

Isoamyl acetate, also known as isopentyl acetate, is an organic compound that is the ester formed from isoamyl alcohol and acetic acid. It is a colorless liquid that is only slightly soluble in water, but very soluble in most organic solvents. Isoamyl acetate has a strong odor which is also described as similar to both banana and pear. Pure isoamyl acetate, or mixtures of isoamyl acetate, amyl acetate, and other flavors may be referred to as Banana oil.

Acetoxy group, abbreviated AcO or OAc, is a chemical functional group of the structure CH3-C(=O)-O-. It differs from the acetyl group CH3-C(=O)- by the presence of one additional oxygen atom. The name acetoxy is the short form of acetyl-oxy.

Dimethyl carbonate chemical compound

Dimethyl carbonate (DMC) is an organic compound with the formula OC(OCH3)2. It is a colourless, flammable liquid. It is classified as a carbonate ester. This compound has found use as a methylating agent and more recently as a solvent that is exempt from the restrictions placed on most volatile organic compounds (VOCs) in the US. Dimethyl carbonate is often considered to be a green reagent.

Cellulose acetate phthalate (CAP), also known as cellacefate (INN) and cellulosi acetas phthalas, is a commonly used polymer phthalate in the formulation of pharmaceuticals, such as the enteric coating of tablets or capsules and for controlled release formulations. It is a cellulose polymer where about half of the hydroxyls are esterified with acetyls, a quarter are esterified with one or two carboxyls of a phthalic acid, and the remainder are unchanged. It is a hygroscopic white to off-white free-flowing powder, granules, or flakes. It is tasteless and odorless, though may have a weak odor of acetic acid. Its main use in pharmaceutics is with enteric formulations. It can be used together with other coating agents, e.g. ethyl cellulose. Cellulose acetate phthalate is commonly plasticized with diethyl phthalate, a hydrophobic compound, or triethyl citrate, a hydrophilic compound; other compatible plasticizers are various phthalates, triacetin, dibutyl tartrate, glycerol, propylene glycol, tripropionin, triacetin citrate, acetylated monoglycerides, etc.

Acetyl iodide is an organoiodine compound with the formula CH3COI. It is a colourless liquid. It is formally derived from acetic acid. Although far rarer in the laboratory than the related acetyl bromide and acetyl chloride, acetyl iodide is produced, transiently at least, on a far larger scale than any other acid halide. Specifically, it is generated by the carbonylation of methyl iodide in the Cativa and Monsanto processes that are the main industrial route to acetic acid. It is also an intermediate in the production of acetic anhydride from methyl acetate.

Potassium methoxide is the alkoxide of methanol with the counterion potassium and is used as a strong base and as a catalyst for transesterification, in particular for the production of biodiesel.

11-Aminoundecanoic acid is an organic compound with the formula H2N(CH2)10CO2H. This white solid is classified as an amine and a fatty acid. 11-Aminoundecanoic acid is a precursor to Nylon-11.

2-Ethoxyethyl acetate is an organic compound with the formula CH3CH2OCH2CH2O2CCH3. It is the ester of ethoxyethanol and acetic acid. A colorless liquid, it is partially soluble in water.

References

  1. Merck Index , 12th Edition, 6089.
  2. 1 2 3 4 5 6 7 NIOSH Pocket Guide to Chemical Hazards. "#0391". National Institute for Occupational Safety and Health (NIOSH).
  3. 1 2 "Methyl acetate". Immediately Dangerous to Life and Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  4. Zeno, W. Wicks, JR, Frank N. Jones, S. Peter Pappas, and Douglas A. Wicks (2007). Organic Coatings. Hoboken, New Jersey: Wiley. ISBN   978-0-471-69806-7.CS1 maint: Multiple names: authors list (link)
  5. "Update: U.S. EPA Exempt Volatile Organic Compounds". American Coatings Association. 2018-01-30. Retrieved 2019-03-20.
  6. Hosea Cheung, Robin S. Tanke, G. Paul Torrence “Acetic Acid” in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim. doi : 10.1002/14356007.a01_045
  7. Zoeller, J. R.; Agreda, V. H.; Cook, S. L.; Lafferty, N. L.; Polichnowski, S. W.; Pond, D. M. (1992). "Eastman Chemical Company Acetic Anhydride Process". Catalysis Today . 13: 73–91. doi:10.1016/0920-5861(92)80188-S.