Aziridine: Difference between revisions
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'''Aziridines''' are [[organic compound]]s containing the three-membered [[heterocycle]] (CH<sub> |
'''Aziridines''' are [[organic compound]]s containing the three-membered [[heterocycle]] (CH<sub>2</sub>)<sub>2</sub>NH.<ref>{{cite book |author=Gilchrist, T.L. |title=Heterocyclic chemistry |isbn=978-0-582-01421-3 }}</ref><ref>''Epoxides and aziridines – A mini review'' Albert Padwaa and S. Shaun Murphreeb [[Arkivoc]] (JC-1522R) pp. 6–33 [http://www.arkat-usa.org/ark/journal/2006/I03_Coxon/1522/JC-1522R.asp Online article]</ref> It is a colorless, highly toxic gas that is mainly of theoretical interest. The class of [[aziridines]] |
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are of broader interest. |
are of broader interest. |
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Revision as of 19:58, 24 November 2019
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| Names | |||
|---|---|---|---|
| Preferred IUPAC name
Aziridine | |||
| Systematic IUPAC name
Azacyclopropane | |||
| Other names
Azirane
Ethylene imine Aminoethylene Dimethyleneimine Dimethylenimine Ethylimine | |||
| Identifiers | |||
3D model (JSmol)
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| 102380 | |||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider | |||
| ECHA InfoCard | 100.005.268 | ||
| EC Number |
| ||
| 616 | |||
| KEGG | |||
PubChem CID
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| RTECS number |
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| UNII | |||
| UN number | 1185 | ||
CompTox Dashboard (EPA)
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| Properties | |||
| C2H5N | |||
| Molar mass | 43.069 g·mol−1 | ||
| Appearance | Clear colorless oily liquid[1] | ||
| Odor | ammonia-like[2] | ||
| Density | 0.8321 g/mL 20 °C[3] | ||
| Melting point | −77.9 °C (−108.2 °F; 195.2 K) | ||
| Boiling point | 56 °C (133 °F; 329 K) | ||
| miscible | |||
| Vapor pressure | 160 mmHg (20° C)[2] | ||
| Hazards | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards
|
highly flammable and toxic | ||
| GHS labelling: | |||
    
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| Danger | |||
| H225, H300, H310, H314, H330, H340, H350, H411 | |||
| P201, P202, P210, P233, P240, P241, P242, P243, P260, P262, P264, P270, P271, P273, P280, P281, P284, P301+P310, P301+P330+P331, P302+P350, P303+P361+P353, P304+P340, P305+P351+P338, P308+P313, P310, P320, P321, P322, P330, P361, P363, P370+P378, P391, P403+P233, P403+P235, P405, P501 | |||
| NFPA 704 (fire diamond) | |||
| Flash point | −11 °C (12 °F; 262 K) | ||
| 322 °C (612 °F; 595 K) | |||
| Explosive limits | 3.6–46% | ||
| Lethal dose or concentration (LD, LC): | |||
LC50 (median concentration)
|
250 ppm (rat, 1 hr) 250 ppm (guinea pig, 1 hr) 62 ppm (rat, 4 hr) 223 ppm (mouse, 2 hr) 56 ppm (rat, 2 hr) 2236 ppm (mouse, 10 min)[4] | ||
LCLo (lowest published)
|
25 ppm (guinea pig, 8 hr) 56 ppm (rabbit, 2 hr)[4] | ||
| NIOSH (US health exposure limits): | |||
PEL (Permissible)
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OSHA-Regulated Carcinogen[2] | ||
REL (Recommended)
|
Ca[2] | ||
IDLH (Immediate danger)
|
Ca [100 ppm][2] | ||
| Related compounds | |||
Related heterocycles
|
Borirane Ethylene oxide Thiirane | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Aziridines are organic compounds containing the three-membered heterocycle (CH2)2NH.[5][6] It is a colorless, highly toxic gas that is mainly of theoretical interest. The class of aziridines are of broader interest.
Structure
The bond angles in aziridine are approximately 60°, considerably less than the normal hydrocarbon bond angle of 109.5°, which results in angle strain as in the comparable cyclopropane and ethylene oxide molecules. A banana bond model explains bonding in such compounds. Aziridine is less basic than acyclic aliphatic amines, with a pKa of 7.9 for the conjugate acid, due to increased s character of the nitrogen free electron pair. Angle strain in aziridine also increases the barrier to nitrogen inversion. This barrier height permits the isolation of separate invertomers, for example the cis and trans invertomers of N-chloro-2-methylaziridine.
Synthesis
An amine functional group displaces the adjacent halide in an intramolecular nucleophilic substitution reaction to generate an aziridine. Amino alcohols have the same reactivity, but the hydroxy group must first be converted into a good leaving group. The cyclization of an amino alcohol is called a Wenker synthesis (1935), and that of a haloamine the Gabriel ethylenimine method (1888).[citation needed]
Safety
Aziridines are subject to attack and ring-opening by endogenous nucleophiles such as nitrogenous bases in DNA base pairs, resulting in potential mutagenicity.[7][8][9]
See also
- Binary ethylenimine, a dimeric form of aziridine
References
- ^ "Aziridine" (PDF). Re-evaluation of Some Organic Chemicals, Hydrazine and Hydrogen Peroxide. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Vol. 71. 1999.
- ^ a b c d e NIOSH Pocket Guide to Chemical Hazards. "#0274". National Institute for Occupational Safety and Health (NIOSH).
- ^ Weast, Robert C.; et al. (1978). CRC Handbook of Chemistry and Physics (59th ed.). West Palm Beach, FL: CRC Press. ISBN 0-8493-0549-7.
- ^ a b "Ethyleneimine". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ Gilchrist, T.L. Heterocyclic chemistry. ISBN 978-0-582-01421-3.
- ^ Epoxides and aziridines – A mini review Albert Padwaa and S. Shaun Murphreeb Arkivoc (JC-1522R) pp. 6–33 Online article
- ^ Kanerva L, Keskinen H, Autio P, Estlander T, Tuppurainen M, Jolanki R (May 1995). "Occupational respiratory and skin sensitization caused by polyfunctional aziridine hardener". Clin Exp Allergy. 25 (5): 432–9. doi:10.1111/j.1365-2222.1995.tb01074.x. PMID 7553246.
- ^ Sartorelli P, Pistolesi P, Cioni F, Napoli R, Sisinni AG, Bellussi L, Passali GC, Cherubini Di Simplicio E, Flori L (2003). "Skin and respiratory allergic disease caused by polyfunctional aziridine". Med Lav. 94 (3): 285–95. PMID 12918320.
- ^ Mapp CE (2001). "Agents, old and new, causing occupational asthma". Occup. Environ. Med. 58 (5): 354–60. doi:10.1136/oem.58.5.354. PMC 1740131. PMID 11303086.