Ethylamine

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Ethylamine
Names
IUPAC name
Ethanamine
Other names
Aminoethane
Monoethylamine
Properties
C2H7N
CH3CH2NH2
Molar mass 45.085 g/mol
Appearance Colorless gas/liquid
Odor Fishy, ammoniacal
Density 688 g/cm3 (15 °C) (liquid)
1.61 g/cm3 (20 °C) (gas)
0.81 g/cm3 (20 °C) (70% aq. sol.)
Melting point −81.2 °C (−114.2 °F; 192.0 K)
Boiling point 16.6 °C (61.9 °F; 289.8 K)
Miscible
Solubility Reacts with acids
Miscible with acetone, benzene, diethyl ether, ethanol, isopropanol, methanol, pyridine, toluene
Vapor pressure 874 mmHg (20 °C)
Acidity (pKa) 10.8
Thermochemistry
−57.7 kJ/mol
Hazards
Safety data sheet Sigma-Aldrich (anhydrous)
Sigma-Aldrich (70% aq. solution)
Flash point −37 °C (−35 °F; 236 K)
Lethal dose or concentration (LD, LC):
400 mg/kg (rat, oral)
265 mg/kg (rabbit, dermal)
1230 ppm (mammal)
Related compounds
Related compounds
Methylamine
Propylamine
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Ethylamine is an organic compound with the formula CH3CH2NH2 or just EtNH2.

Properties

Chemical

Like other simple aliphatic amines, ethylamine is a weak base, with a pKa of 10.8.

Ethylamine reacts with acids to form their respective salts.

Reaction with sulfuryl chloride followed by oxidation of the sulfonamide gives diethyldiazene or azoethane (EtN=NEt).[1]

Ethylamine may be oxidized using a strong oxidizer such as potassium permanganate to form acetaldehyde.

Physical

Ethylamine is a colorless gas that condenses just below room temperature to a liquid. It has a strong fish-like odor. Ethylamine is miscible with a variety of solvents, but reacts with acids. Sol. of 70% aq. ethylamine have a density of 0.81 g/mL at 20 °C.

Availability

Ethylamine is sold by chemical suppliers. Since it's classified as List I drug precursor in most countries, it's almost impossible to be acquired by the hobby chemist without a permit. In the United States it is classified as a DEA List I chemical.

Preparation

Ethylamine is produced industrially from the reaction of ethanol and ammonia, in the presence of an oxide catalyst:

CH3CH2OH + NH3 → CH3CH2NH2 + H2O

In this reaction, ethylamine is coproduced together with diethylamine and triethylamine. Fractional distillation is often used to purify the components.

A simpler route involves reductive amination of acetaldehyde:

CH3CHO + NH3 + H2 → CH3CH2NH2 + H2O

Other routes involve reacting ethylene and ammonia in the presence of catalyst, such as sodium amide or other related basic catalysts.[2]

H2C=CH2 + NH3 → CH3CH2NH2

Hydrogenation of acetonitrile, acetamide and nitroethane will also yield ethylamine. These reactions can be effected stoichiometrically using lithium aluminium hydride.

In another route, ethylamine can be synthesized via nucleophilic substitution of a haloethane (such as chloroethane or bromoethane) with ammonia, utilizing a strong base such as potassium hydroxide. Side products, such as diethylamine and triethylamine are also produced.[3]

CH3CH2Cl + NH3 + KOH → CH3CH2NH2 + KCl + H2O

Projects

  • Make ethylammonium salts
  • Make simazine

Handling

Safety

Ethylamine is toxic in high concentrations. It's also flammable and mixtures with air in a confined place can be explosive.

Storage

Ethylamine can be stored in compressed cylinders at standard conditions. Alternatively, it may be stored as salt or dissolved in a solvent of choice. Storing it in a fridge or freezer as liquid in a bottle is not recommended.

Disposal

Ethylamine and its salts aren't harmful to the environment and usually don't require special disposal. If you have small amounts, you can dilute the salt and pour it down the drain or in the ground, where it will break down into less harmful products.

References

  1. https://web.archive.org/web/20070930230511/http://www.orgsyn.org/orgsyn/pdfs/CV6P0078.pdf
  2. https://www.freepatentsonline.com/7161039.pdf
  3. http://www.docbrown.info/page06/OrgMechs2b.htm

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