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Ethylenediamine

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Ethylenediamine
Skeletal formula of ethylenediamine
Ball and stick model of ethylenediamine
Ball and stick model of ethylenediamine
Space-filling model of ethylenediamine
Space-filling model of ethylenediamine
Names
Preferred IUPAC name
Ethane-1,2-diamine[2]
Other names
Edamine,[1] 1,2-Diaminoethane, 'en' when a ligand
Identifiers
3D model (JSmol)
Abbreviations en
605263
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.003.154 Edit this at Wikidata
EC Number
  • 203-468-6
1098
KEGG
MeSH ethylenediamine
RTECS number
  • KH8575000
UNII
UN number 1604
  • InChI=1S/C2H8N2/c3-1-2-4/h1-4H2 checkY
    Key: PIICEJLVQHRZGT-UHFFFAOYSA-N checkY
  • NCCN
Properties
C2H8N2
Molar mass 60.100 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]
miscible
log P −2.057
Vapor pressure 1.3 kPa (at 20 °C)
5.8 mol Pa−1 kg−1
  • −46.26×10−6 cm3 mol−1
  • −76.2×10−6 cm3 mol−1 (HCl salt)
1.4565
Thermochemistry
172.59 J K−1 mol−1
202.42 J K−1 mol−1
−63.55 to −62.47 kJ mol−1
−1.8678 to −1.8668 MJ mol−1
Hazards
GHS labelling:
GHS02: Flammable GHS06: Toxic GHS05: Corrosive GHS08: Health hazard
Danger
H226, H302, H311, H314, H317, H332, H334, H412
P101, P102, P260, P273, P280, P305+P351+P338, P308+P313, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
2
0
Flash point 34 °C (93 °F; 307 K)[3]
385 °C (725 °F; 658 K)[3]
Explosive limits 2.7–16%
Lethal dose or concentration (LD, LC):
500 mg/kg (oral, rat)
470 mg/kg (oral, guinea pig)
1160 mg/kg (oral, rat)[5]
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 10 ppm (25 mg/m3)[4]
REL (Recommended)
TWA 10 ppm (25 mg/m3)[4]
IDLH (Immediate danger)
1000 ppm[4]
Related compounds
Related alkanamines
1,2-Diaminopropane, 1,3-Diaminopropane
Related compounds
Ethylamine, Ethylenedinitramine
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

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 basic amine. It is a widely used building block in chemical synthesis, with approximately 500,000 tonnes produced in 1998.[6] Ethylenediamine is the first member of the so-called polyethylene amines.

Synthesis

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Ethylenediamine is produced industrially by treating 1,2-dichloroethane with ammonia under pressure at 180 °C in an aqueous medium:[6][7]

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 [de]. Diethylenetriamine (DETA) and triethylenetetramine (TETA) are formed as by-products.

Another industrial route to ethylenediamine involves the reaction of ethanolamine and ammonia:[8]

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

It can be produced in the lab by the reaction of ethylene glycol and urea.[citation needed]

Ethylenediamine can be purified by treatment with sodium hydroxide to remove water followed by distillation.[9]

Applications

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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 amino groups, it readily forms heterocycles such as imidazolidines.

Precursor to chelation agents, drugs, and agrochemicals

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A most prominent derivative of ethylenediamine is the chelating agent EDTA, which is derived from ethylenediamine via a Strecker synthesis involving cyanide and formaldehyde. Hydroxyethylethylenediamine is another commercially significant chelating agent.[6] Numerous bio-active compounds and drugs contain the N–CH2–CH2–N linkage, including some antihistamines.[10] Salts of ethylenebisdithiocarbamate are commercially significant fungicides under the brand names Maneb, Mancozeb, Zineb, and Metiram. Some imidazoline-containing fungicides are derived from ethylenediamine.[6]

Pharmaceutical ingredient

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Ethylenediamine is an ingredient in the common bronchodilator drug aminophylline, where it serves to solubilize the active ingredient theophylline. Ethylenediamine has also been used in dermatologic preparations, but has been removed from some because of causing contact dermatitis.[11] When used as a pharmaceutical excipient, after oral administration its bioavailability is about 0.34, due to a substantial first-pass effect. Less than 20% is eliminated by renal excretion.[12]

Ethylenediamine-derived antihistamines are the oldest of the five classes of first-generation antihistamines, beginning with piperoxan aka benodain, discovered in 1933 at the Pasteur Institute in France, and also including mepyramine, tripelennamine, and antazoline. The other classes are derivatives of ethanolamine, alkylamine, piperazine, and others (primarily tricyclic and tetracyclic compounds related to phenothiazines, tricyclic antidepressants, as well as the cyproheptadine-phenindamine family)

Role in polymers

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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.[6]

Tetraacetylethylenediamine

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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.

Other applications

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Coordination chemistry

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Ethylenediamine is a well-known bidentate chelating ligand for coordination compounds, with the two nitrogen atoms donating their lone pairs of electrons when ethylenediamine acts as a ligand. It is often abbreviated "en" in inorganic chemistry. The complex [Co(en)3]3+ is a well studied example. Schiff base ligands easily form from ethylenediamine. For example, the diamine condenses with 4-Trifluoromethylbenzaldehyde to give to the diimine.[13] The salen ligands, some of which are used in catalysis, are derived from the condensation of salicylaldehydes and ethylenediamine.

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Related derivatives of ethylenediamine include ethylenediaminetetraacetic acid (EDTA), tetramethylethylenediamine (TMEDA), and tetraethylethylenediamine (TEEDA). Chiral analogs of ethylenediamine include 1,2-diaminopropane and trans-diaminocyclohexane.

Safety

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Ethylenediamine, like ammonia and other low-molecular weight amines, is a skin and respiratory irritant. Unless tightly contained, liquid ethylenediamine will release toxic and irritating vapors into its surroundings, especially on heating. The vapors absorb moisture from humid air to form a characteristic white mist, which is extremely irritating to skin, eyes, lungs and mucous membranes.

References

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  1. ^ "32007R0129". European Union. 12 February 2007. Annex II. Retrieved 3 May 2012.
  2. ^ International Union of Pure and Applied Chemistry (2014). Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013. The Royal Society of Chemistry. p. 676. doi:10.1039/9781849733069. ISBN 978-0-85404-182-4.
  3. ^ a b c d e f g Record in the GESTIS Substance Database of the Institute for Occupational Safety and Health
  4. ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0269". National Institute for Occupational Safety and Health (NIOSH).
  5. ^ "Ethylenediamine". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  6. ^ a b c d e Eller, Karsten; Henkes, Erhard; Rossbacher, Roland; Höke, Hartmut (2005). "Amines, Aliphatic". Amines, Aliphatic. Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH Verlag. doi:10.1002/14356007.a02_001. ISBN 3-527-30673-0.
  7. ^ Arpe, Hans-Jürgen (2007). Industrielle Organische Chemie (6th ed.). Wiley VCH. p. 245.{{cite book}}: CS1 maint: location missing publisher (link)
  8. ^ Hans-Jürgen Arpe, Industrielle Organische Chemie, 6. Auflage (2007), Seite 275, Wiley VCH
  9. ^ Rollinson, Carl L.; Bailar, John C. Jr. (1946). "Tris(ethylenediamine)chromium(III) Salts". Inorganic Syntheses. Vol. 2. pp. 196–200. doi:10.1002/9780470132333.ch60. ISBN 978-0-470-13233-3.
  10. ^ Kotti, S. R. S. S.; Timmons, C.; 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. S2CID 37177899.
  11. ^ Hogan DJ (January 1990). "Allergic contact dermatitis to ethylenediamine. A continuing problem". Dermatol Clin. 8 (1): 133–6. doi:10.1016/S0733-8635(18)30536-9. PMID 2137392.
  12. ^ Zuidema, J. (1985-08-23). "Ethylenediamine, profile of a sensitizing excipient". Pharmacy World & Science. 7 (4): 134–140. doi:10.1007/BF02097249. PMID 3900925. S2CID 11016366.
  13. ^ Habibi, Mohammad Hossein; Montazerozohori, Morteza; Lalegani, Arash; Harrington, Ross W.; Clegg, William (2006). "Synthesis, structural and spectroscopic properties of a new Schiff base ligand N,N′-bis(trifluoromethylbenzylidene)ethylenediamine". Journal of Fluorine Chemistry. 127 (6): 769–773. doi:10.1016/j.jfluchem.2006.02.014.
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