Ethylenediamine

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Ethylenediamine
Skeletal formula of ethylenediamine
Ball and stick model of ethylenediamine Space-filling model of ethylenediamine
Sample of ethylenediamine in a jar
Identifiers
Abbreviations en
CAS number 107-15-3 YesY
PubChem 3301
ChemSpider 13835550 YesY
UNII 60V9STC53F YesY
EC number 203-468-6
UN number 1604
KEGG D01114 YesY
MeSH ethylenediamine
ChEBI CHEBI:30347 YesY
ChEMBL CHEMBL816 YesY
RTECS number KH8575000
Beilstein Reference 605263
Gmelin Reference 1098
Jmol-3D images Image 1
Properties
Molecular formula C2H8N2
Molar mass 60.10 g mol−1
Appearance Colorless liquid[3]
Odor Ammoniacal[3]
Density 0.90 g/cm3[3]
Melting point 8 °C (46 °F; 281 K)[3]
Boiling point 116 °C (241 °F; 389 K)[3]
log P −2.057
Vapor pressure 1.3 kPa (at 20 °C)
kH 5.8 mol Pa−1 kg−1
Refractive index (nD) 1.4565
Thermochemistry
Specific
heat capacity
C
172.59 J K−1 mol−1
Std molar
entropy
So298
202.42 J K−1 mol−1
Std enthalpy of
formation
ΔfHo298
−63.55–−62.47 kJ mol−1
Std enthalpy of
combustion
ΔcHo298
−1.8678–−1.8668 MJ mol−1
Hazards
GHS pictograms The flame pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) The corrosion pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) The exclamation-mark pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) The health hazard pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)
GHS signal word DANGER
GHS hazard statements H226, H302, H312, H314, H317, H334
GHS precautionary statements P261, P280, P305+351+338, P310
EU Index 612-006-00-6
EU classification Corrosive C
R-phrases R10, R21/22, R34, R42/43
S-phrases (S1/2), S26, S36/37/39, S45
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., gasoline) Health code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gas Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point 34 °C (93 °F; 307 K)[3]
Autoignition temperature 385 °C (725 °F; 658 K)[3]
Explosive limits 2.7–16%
LD50 1.2 g kg−1 (oral, rat)
Related compounds
Related alkanamines 1,2-Diaminopropane, 1,3-Diaminopropane
Related compounds ethylamine
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
Infobox references

Ethylenediamine (abbreviated as en when a ligand) is the organic compound with the formula C2H4(NH2)2. This colorless liquid with an ammonia-like odor is a strongly basic amine. It is a widely used building block in chemical synthesis, with approximately 500000000 kg being produced in 1998.[4] Ethylenediamine readily reacts with moisture in humid air to produce a corrosive, toxic and irritating mist, to which even short exposures can cause serious damage to health (see safety).

Synthesis[edit]

Ethylenediamine is manufactured industrially from 1,2-dichloroethane and ammonia under pressure at 180 °C in an aqueous medium:[4][5]

Ethylendiamin Darstellung.svg

In this reaction hydrogen chloride is generated, which forms a salt with the amine. The amine is liberated by addition of sodium hydroxide and can then be recovered by rectification. Diethylenetriamine (DETA) and triethylenetetramine (TETA) are formed as by-products.

Another industrial route to ethylenediamine involves the reaction of ethanolamine and ammonia:[6]

EDA synthesis from MEOA.svg

This process involves passing the gaseous reactants over a bed of nickel heterogeneous catalysts.

Applications[edit]

Ethylenediamine is used in large quantities for production of many industrial chemicals. It forms derivatives with carboxylic acids (including fatty acids), nitriles, alcohols (at elevated temperatures), alkylating agents, carbon disulfide, and aldehydes and ketones. Because of its bifunctional nature, having two amines, it readily forms heterocycles such as imidazolidines.

Chelating agent and precursor to other ligands[edit]

Ethylenediamine is a well-known chelating ligand for coordination compounds, such as [Co(ethylenediamine)3]3+. The most prominent derivative of ethylenediamine is EDTA, which is derived from ethylenediamine via a Strecker synthesis involving cyanide and formaldehyde. Hydroxyethylethylenediamine is another commercially significant chelating agent. The salen ligands, derived from the condensation of salicylaldehydes and ethylenediamine, are popular chelating agents in the research laboratory although not commercially significant.[4]

Precursor to pharmaceuticals and agrochemicals[edit]

Numerous bio-active compounds contain the N-CH2-CH2-N linkage, including aminophylline and some antihistamines.[7] Salts of ethylenebisdithiocarbamate are commercially significant fungicides under the brand names Maneb, Mancozeb, Zineb, and Metiram. Some imidazoline-containing fungicides are derived from ethylenediamine.[4]

Role in polymers[edit]

Ethylenediamine, because it contains two amine groups, is a widely used precursor to various polymers. Condensates derived from formaldehyde are plasticizers. It is widely used in the production of polyurethane fibers. The PAMAM class of dendrimers are derived from ethylenediamine.[4]

Tetraacetylethylenediamine[edit]

The bleaching activator tetraacetylethylenediamine is generated from ethylenediamine. The derivative N,N-ethylenebis(stearamide) (EBS) is a commercially significant mold-release agent and a surfactant in gasoline and motor oil.

Specialized applications[edit]

Ethylenamine derivatives[edit]

Ethylenediamine is the first member of the so-called polyethylene amines, other members being:

  • Diethylenetriamine, abbreviated dien or DETA, (H2N-CH2CH2-NH-CH2CH2-NH2, an analog of diethylene glycol)
  • Triethylenetetramine, abbreviated trien or TETA, (H2N-CH2CH2-NH-CH2CH2-NH-CH2CH2-NH2)
  • Tetraethylenepentamine, abbreviated TEPA, (H2N-CH2CH2-NH-CH2CH2-NH-CH2CH2-NH-CH2CH2-NH2),
  • Pentaethylenehexamine, abbreviated PEHA, (H2N-CH2CH2-NH-CH2CH2-NH-CH2CH2-NH-CH2CH2-NH-CH2CH2-NH2), up to polyethylene amine. Similarly piperazine is an analogue of dioxane.

Related derivatives of ethylenediamine include tetramethylethylenediamine (abbreviated TMEDA), (CH3)2N-CH2CH2-N(CH3)2 and tetraethylethylenediamine (abbreviated TEEDA) (C2H5)2N-CH2CH2-N(C2H5)2

Safety[edit]

Ethylenediamine, like most amines, is a skin irritant. It was used in commercially available skin products including Mycolog cream.[8] Unless tightly contained, ethylenediamine will release toxic and irritating vapors into its surroundings, especially on heating. The vapors react with moisture in humid air to form a characteristic white mist, which is extremely irritating to skin, eyes, lungs and mucus membranes. Exposure to a relatively small amount of vapor or mist by inhalation can seriously damage health and may even result in death.[9] Ethylenediamine has a half-life of about 30 minutes and a small volume of distribution of 0.133 liters/kg. After oral administration its bioavailability is about 0.34, due to a substantial first-pass effect. Less than 20% is eliminated by urinal excretion.[10]

References[edit]

  1. ^ "ethylenediamine - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 16 September 2004. Identification and Related Records. Retrieved 3 May 2012. 
  2. ^ "32007R0129". European Union. 12 February 2007. Annex II. Retrieved 3 May 2012. 
  3. ^ a b c d e f g Record in the GESTIS Substance Database from the IFA
  4. ^ a b c d e Karsten Eller, Erhard Henkes, Roland Rossbacher, Hartmut Höke "Amines, Aliphatic" in Ullmann's Encyclopedia of Industrial Chemistry, 2005 Wiley-VCH Verlag, Weinheim. doi:10.1002/14356007.a02_001
  5. ^ Hans-Jürgen Arpe, Industrielle Organische Chemie, 6. Auflage (2007), Seite 245, Wiley VCH
  6. ^ Hans-Jürgen Arpe, Industrielle Organische Chemie, 6. Auflage (2007), Seite 275, Wiley VCH
  7. ^ Kotti, S. R. S. S.; Timmons, C. and Li, G. (2006). "Vicinal diamino functionalities as privileged structural elements in biologically active compounds and exploitation of their synthetic chemistry". Chemical Biology & Drug Design 67 (2): 101–114. doi:10.1111/j.1747-0285.2006.00347.x. PMID 16492158. 
  8. ^ Hogan DJ. (January 1990). "Allergic contact dermatitis to ethylenediamine. A continuing problem.". Dermatol Clin. 8 (1): 133–6. PMID 2137392. 
  9. ^ Material Safety Data Sheet
  10. ^ Zuidema J. (1985-08-23). "Ethylenediamine, profile of a sensitizing excipient.". Pharmacy World & Science 7 (4): 134–40. doi:10.1007/BF02097249. PMID 3900925. 

External links[edit]