Difference between revisions of "Methyl acetate"
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| pKb = | | pKb = | ||
| Solubility = 24.4 g/100 ml (at 20 °C) | | Solubility = 24.4 g/100 ml (at 20 °C) | ||
| − | | SolubleOther = Miscible with alcohols, ethers | + | | SolubleOther = Miscible with alcohols, ethers, ketones |
| Solvent = | | Solvent = | ||
| VaporPressure = 173 mmHg (at 20°C) | | VaporPressure = 173 mmHg (at 20°C) | ||
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| − | '''Methyl acetate''' (or '''MeOAc''') is an organic compound which is liquid at room temperature and widely used as a solvent. It has the chemical formula '''CH<sub>3</sub>COOCH<sub>3</sub>'''. | + | '''Methyl acetate''' (or '''MeOAc''') is an organic compound which is liquid at room temperature and widely used as a solvent. It has the chemical formula '''CH<sub>3</sub>COOCH<sub>3</sub>'''. Methyl acetate is the ester of [[acetic acid]] and [[methanol]]. |
==Properties== | ==Properties== | ||
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===Physical=== | ===Physical=== | ||
| − | Methyl acetate is a volatile colorless liquid, somewhat soluble in water (25%) and miscible with other organic solvents such as alcohols and ethers. Methyl acetate has a melting point of −98 °C. Its boiling point of 56.9 °C is very close to that of [[acetone]] (56.05 °C). | + | Methyl acetate is a volatile colorless liquid, somewhat soluble in water (25%) and miscible with other organic solvents such as alcohols and ethers. Methyl acetate has a melting point of −98 °C. Its boiling point of 56.9 °C is very close to that of [[acetone]] (56.05 °C), making the separation of a mixture of the two compounds via fractional distillation complicated. |
==Availability== | ==Availability== | ||
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==Preparation== | ==Preparation== | ||
| − | Methyl acetate can be made via Fischer esterification, between anhydrous [[methanol]] and glacial [[acetic acid]]. A catalyst such as [[sulfuric acid]] is used, though [[iron(III) sulfate]] can also be used. The process takes place under reflux. | + | Methyl acetate can be made via Fischer esterification, between anhydrous [[methanol]] and glacial [[acetic acid]]. A catalyst such as [[sulfuric acid]] is used, though [[iron(III) sulfate]] can also be used. The process takes place under reflux. After the reaction has ended, leftover acetic acid is neutralized using sodium bicarbonate. The crude methyl acetate is extracted using a separatory funnel and dried using [[calcium chloride]]. If required, the methyl acetate can be further purified via fractionated distillation. |
| + | |||
| + | For better yield, [[acetic anhydride]] can be used instead of acetic acid. | ||
==Projects== | ==Projects== | ||
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===Disposal=== | ===Disposal=== | ||
| − | Methyl acetate can be safely burned, preferably outside. Hydrolysis yields acetic acid and methanol. | + | Methyl acetate can be safely burned, preferably outside. Hydrolysis yields acetic acid and methanol which can either be recovered or destroyed. |
==References== | ==References== | ||
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[[Category:Acetates]] | [[Category:Acetates]] | ||
[[Category:Solvents]] | [[Category:Solvents]] | ||
| + | [[Category:Polar solvents]] | ||
[[Category:Aprotic solvents]] | [[Category:Aprotic solvents]] | ||
[[Category:Fragrant compounds]] | [[Category:Fragrant compounds]] | ||
Latest revision as of 11:29, 5 May 2018
| Names | |
|---|---|
| IUPAC name
Methyl acetate
| |
| Systematic IUPAC name
Methyl ethanoate | |
| Other names
MeOAc
Methyl ethanoate Methyl ester of acetic acid | |
| Identifiers | |
| Jmol-3D images | Image |
| |
| Properties | |
| CH3COOCH3 C3H6O2 | |
| Molar mass | 74.08 g/mol |
| Appearance | Colorless liquid |
| Odor | Fragrant, fruity, nail polisher-like |
| Density | 0.9342 g/cm3 (at 20 °C) |
| Melting point | −98 °C (−144 °F; 175 K) |
| Boiling point | 56.9 °C (134.4 °F; 330.0 K) |
| 24.4 g/100 ml (at 20 °C) | |
| Solubility | Miscible with alcohols, ethers, ketones |
| Vapor pressure | 173 mmHg (at 20°C) |
| Hazards | |
| Safety data sheet | ScienceLab |
| Flash point | −10 °C |
| Lethal dose or concentration (LD, LC): | |
| LD50 (Median dose)
|
3700 mg/kg (oral, rabbit) |
| LC50 (Median concentration)
|
11,039 ppm (mouse, 4 hr) 21,753 ppm (cat, 1 hr) 32,000 ppm (rat, 4 hr) |
| Related compounds | |
| Related compounds
|
Methyl formate Ethyl formate Ethyl acetate |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Methyl acetate (or MeOAc) is an organic compound which is liquid at room temperature and widely used as a solvent. It has the chemical formula CH3COOCH3. Methyl acetate is the ester of acetic acid and methanol.
Contents
Properties
Chemical
Methyl acetate is carbonylated under high pressure (50 atm) and temperature (190 °C) to yield acetic anhydride:
- CH3CO2CH3 + CO → (CH3CO)2O
This reaction takes place in the presence of various catalysts.
Physical
Methyl acetate is a volatile colorless liquid, somewhat soluble in water (25%) and miscible with other organic solvents such as alcohols and ethers. Methyl acetate has a melting point of −98 °C. Its boiling point of 56.9 °C is very close to that of acetone (56.05 °C), making the separation of a mixture of the two compounds via fractional distillation complicated.
Availability
Methyl acetate is found in various paint thinners and sometimes in nail polishers. Fractional distillation is required to separate it.
Methyl acetate is sometimes found mixed with ethyl acetate, in certain (poly)urethane strippers.
Preparation
Methyl acetate can be made via Fischer esterification, between anhydrous methanol and glacial acetic acid. A catalyst such as sulfuric acid is used, though iron(III) sulfate can also be used. The process takes place under reflux. After the reaction has ended, leftover acetic acid is neutralized using sodium bicarbonate. The crude methyl acetate is extracted using a separatory funnel and dried using calcium chloride. If required, the methyl acetate can be further purified via fractionated distillation.
For better yield, acetic anhydride can be used instead of acetic acid.
Projects
- Organic extractions
- Acetic anhydride synthesis
Handling
Safety
Methyl acetate is flammable. While it is considered a mild skin irritant, methyl acetate poses little toxicity.
Storage
Methyl acetate should be stored in closed bottles, and kept away from moisture, acidic vapors and bases. Due to its relative low boiling point, it's best to keep it in a cool place, especially during summer.
Disposal
Methyl acetate can be safely burned, preferably outside. Hydrolysis yields acetic acid and methanol which can either be recovered or destroyed.
References
Relevant Sciencemadness threads
- Chemical pages without CAS Registry Number
- Articles without EBI source
- Chemical pages without ChemSpiderID
- Chemical pages without DrugBank identifier
- Articles without KEGG source
- Articles without InChI source
- Articles without UNII source
- Articles containing unverified chemical infoboxes
- Chembox articles without image
- Chemical compounds
- Organic compounds
- Esters
- Acetates
- Solvents
- Polar solvents
- Aprotic solvents
- Fragrant compounds
- Materials unstable in basic solution
- Readily available chemicals
- Liquids
