Diethylamine (DEA) – C4H11N, 109-89-7

Diethylamine (DEA) is a chemical compound that has a strong odor similar to ammonia. It is used in the production of pesticides, pharmaceuticals, and rubber accelerators. It can cause irritation to the skin, eyes, and respiratory system.

IUPAC NameN,N-diethylmethanamine
Molecular FormulaC4H11N
CAS Number109-89-7
SynonymsN-ethyl-ethanamine, DEA, Diethylamino, N,N-diethylamine, N-ethylethanamine, Diethylamine

Diethylamine Properties

Diethylamine Formula

The formula for diethylamine is C4H11N. It is a primary aliphatic amine with two ethyl groups attached to the nitrogen atom. The molecular structure of diethylamine contains a central nitrogen atom that is bonded to two ethyl groups and a hydrogen atom.

Diethylamine Molar Mass

The molar mass of DEA is 73.14 g/mol. This is calculated by adding the atomic masses of all the atoms present in one molecule of DEA. The molar mass is an important parameter that is used to calculate the amount of DEA required for a given chemical reaction.

Diethylamine Boiling Point

The boiling point of DEA is 55.8°C. This means that at this temperature, the liquid form of DEA will begin to vaporize and turn into a gas. The boiling point is an important parameter that determines the conditions required for a chemical reaction to take place.

Diethylamine Melting Point

The melting point of DEA is -49.8°C. This means that at this temperature, the solid form of DEA will start to melt and turn into a liquid. The melting point is an important parameter that is used to determine the purity of DEA.

Diethylamine Density g/mL

The density of DEA is 0.707 g/mL. This means that one milliliter of DEA weighs 0.707 grams. The density is an important parameter that is used to calculate the amount of DEA required for a given chemical reaction.

Diethylamine Molecular Weight

The molecular weight of DEA is 73.14 g/mol. This is the sum of the atomic weights of all the atoms in one molecule of DEA. The molecular weight is an important parameter that is used to calculate the amount of DEA required for a given chemical reaction.

Diethylamine Structure

Diethylamine

DEA has a linear molecular structure, with the central nitrogen atom bonded to two ethyl groups and a hydrogen atom. The molecule has a trigonal pyramidal shape due to the lone pair of electrons on the nitrogen atom. This structure is important in determining the reactivity and properties of DEA.

Diethylamine Solubility

DEA is soluble in water and many organic solvents. It has a pKa of 10.75, which means it is a weak base. The solubility of DEA is dependent on factors such as the temperature, pH, and polarity of the solvent. Its solubility in water is 100 g/L at 25°C.

AppearanceColorless liquid
Specific Gravity0.707 g/mL
ColorColorless
OdorAmmonia-like
Molar Mass73.14 g/mol
Density0.707 g/mL
Melting Point-49.8°C
Boiling Point55.8°C
Flash Point-15°C
Water SolubilitySoluble
SolubilitySoluble in many organic solvents
Vapour Pressure94.7 mmHg at 25°C
Vapour Density2.5
pKa10.75
pHBasic

Diethylamine Safety and Hazards

DEA can be hazardous to human health if not handled properly. It is corrosive and can cause skin, eye, and respiratory irritation upon contact. Prolonged exposure to DEA can cause damage to the liver and kidneys. It is flammable and can form explosive mixtures with air. Special precautions such as proper ventilation, personal protective equipment, and fire-resistant storage containers should be taken when handling DEA. In case of accidental exposure, immediate medical attention should be sought. It is important to follow all safety guidelines and protocols when working with DEA to ensure the safety of oneself and others.

Hazard SymbolsCorrosive, Flammable
Safety DescriptionKeep away from heat, sparks, open flames, and hot surfaces. Avoid breathing vapors, mist, or gas. Wear protective gloves, eye protection, and face protection. Use in a well-ventilated area.
UN IDsUN 1154
HS Code29211990
Hazard Class3
Packing GroupII
ToxicityMay cause skin, eye, and respiratory irritation. Prolonged exposure can cause damage to the liver and kidneys.

Diethylamine Synthesis Methods

Several methods exist to synthesize DEA, including reacting ethanol and ammonia or reacting diethyl sulfate and ammonia.

One method involves heating a mixture of ethanol and ammonia in the presence of a catalyst, such as alumina or silica gel. The reaction produces DEA and water, which can be separated through distillation.

Another method involves the reaction of diethyl sulfate with ammonia. The reaction takes place in a solvent, such as methanol or ethanol, and produces DEA sulfate. To produce DEA and sodium sulfate, one can treat the DEA sulfate with a strong base, such as sodium hydroxide.

To synthesize DEA, one can react ethylene with ammonia in the presence of a catalyst, such as iron oxide. The reaction produces a mixture of DEA and triethylamine, which can be separated through distillation.

When synthesizing DEA, one must exercise caution since the reactants and products can pose risks to both human health and the environment. Therefore, it is necessary to use appropriate safety measures and equipment during the synthesis process.

Diethylamine Uses

DEA has several uses across different industries due to its unique properties. Here are some of its common uses:

  • Pharmaceuticals: Used as a building block in the synthesis of pharmaceuticals, such as local anesthetics and antihistamines.
  • Agricultural chemicals: Used as raw material in the production of herbicides, such as glyphosate.
  • Rubber industry: Used in the production of accelerators for the vulcanization of rubber.
  • Dye industry: Used in the production of dyes and pigments, such as acid dyes and reactive dyes.
  • Corrosion inhibitors: Used as a corrosion inhibitor in the petroleum industry to protect pipelines and storage tanks from corrosion.
  • Solvents: Used as a solvent in the production of synthetic resins and polymers.
  • Chemical synthesis: Also used as a reagent in a wide range of chemical synthesis reactions.

Questions:

Q: Which is more basic, triethylamine or diethylamine?

A: Triethylamine is more basic than DEA due to its larger size and the presence of three ethyl groups which contribute to increased electron density.

Q: What is the pH of 0.10 M diethylamine, (CH3CH2)2NH, (Kb = 8.6 × 10−4)?

A: The pH of a 0.10 M DEA solution can be calculated using the Kb value and the equation for the base dissociation constant. The pH of the solution is approximately 10.49.

Q: What is the pH of 0.11 M diethylamine, (CH3CH2)2NH, (Kb = 8.6 × 10−4)?

A: The pH of a 0.11 M DEA solution can be calculated using the Kb value and the equation for the base dissociation constant. The pH of the solution is approximately 10.50.

Q: What is the standard enthalpy of formation of liquid diethylamine, (CH3CH2)2NH?

A: The standard enthalpy of formation of liquid DEA is -42.52 kJ/mol.

Q: Is diethylamine polar?

A: Yes, DEA is polar due to the presence of a nitrogen atom with a lone pair of electrons and the difference in electronegativity between nitrogen and carbon.

Q: Which is more basic, diethylamine or triethylamine?

A: Triethylamine is more basic than DEA due to the presence of three ethyl groups which contribute to increased electron density.

Q: What is the pH of a 0.10 M diethylamine solution?

A: The pH of a 0.10 M DEA solution can be calculated using the Kb value and the equation for the base dissociation constant. The pH of the solution is approximately 10.49.

Q: Is diethylamine a strong or weak acid?

A: DEA is a weak base, not a strong acid. It reacts with water to produce hydroxide ions and diethylammonium ions.