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Amyl nitrite

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Amyl nitrite
Chemical structure of amyl nitrite
Ball-and-stick model of amyl nitrite
General
Systematic name 3-methyl-1-nitrosooxybutane
Other names Isoamyl nitrite
Nitramyl
3-methyl-1-nitrosooxybutane
Pentyl alcohol nitrite(ambiguous)
Nitrous acid, pentyl ester(ambiguous)
Molecular formula C5H11NO2
SMILES CC(C)CCON=O
Molar mass 117.15 g/mol
Appearance Colourless liquid
CAS number [110-46-3]
Properties
Density and phase 0.872 g/cm3, liquid (25 °C)
Solubility in water Low
Other solvents soluble in organic solvents
Melting point ?? °C
Boiling point 99 °C
Hazards
MSDS External MSDS
Main hazards vasodialator
NFPA 704 ?
R/S statement R: 11-20/22
S: 16-24-46
RTECS number NT0187500
Flash point 21 °C
Supplementary data page
Structure and
properties]]
n = 1.386
Spectral data UV, IR, NMR, MS
Related compounds
Related compounds nitroglycerine
isopentanol
Butyl nitrite
Isobutyl nitrite
Ethyl nitrite


Methyl nitrite
Isopropyl nitrite
Cyclohexyl nitrite

Except where noted otherwise, data are given for
materials in their standard state (at 25°C, 100 kPa)
Infobox disclaimer and references

Amyl nitrite is the chemical compound with the formula C5H11ONO. A variety of isomers are known, but they all feature an amyl group attached to the nitrito functional group. The alkyl substituent is not reactive, but the ON=O group behaves as other nitrites. Like other alkyl nitrites, amyl nitrite is bioactive in mammals, being a vasodilator which is the basis of its use in medicine and as a recreational drug.

Nomenclature

The term "amyl nitrite" encompasses a several isomers. For example, a common form of amyl nitrite with the formula (CH3)2CHCH2CH2ONO may be more specifically referred to as isoamyl nitrite. When the amyl chain consists of five carbon atoms in a row, the resulting "amyl nitrite" would be described with the structural formula CH3(CH2)4ONO. Sometimes the latter isomer is called n-amyl nitrite, n denoting normal. Also, the five carbon chain is sometimes referred to as a straight chain, although chains of carbon atoms are usually zig-zag in conformation.

Amyl nitrite is often confused with amyl nitrate, a substance with a different chemical composition and different properties.

Synthesis and reactions

Alkyl nitrites are prepared by the reaction of alcohols with nitrous acid:[1]

C5H11OH + HONO →→ C5H11ONO + H2O

The reaction is analogous to esterification. The resulting isoamyl nitrite decomposes in the presence of base to give nitrite salts and the isoamyl alcohol:

C5H11ONO + NaOH → C5H11OH + NaNO2

Amyl nitrite, like other alkyl nitrites, reacts with carbanions to give oximes.[2]

Physiological effects

Amyl nitrite, in common with other alkyl nitrites[3], is a potent vasodilator, i.e. it expands blood vessels, resulting in lowering of the blood pressure. Alkyl nitrites function as a source of nitric oxide, which signals for relaxation of the involuntary muscles. Physical effects include decrease in blood pressure, headache, flushing of the face, increased heart rate, dizziness, and relaxation of involuntary muscles, especially the blood vessel walls and the anal sphincter. There are no withdrawal symptoms. Overdose symptoms include nausea, emesis (vomiting), hypotension, hypoventilation, dyspnea (shortness of breath), and syncope (fainting).

It induces the formation of methemoglobin, which sequesters cyanide as non-toxic cyanomethemoglobin.[4]

Applications

Amyl nitrite is employed medically to treat heart diseases such as angina and to treat cyanide poisoning.[5] It is also used as a recreational inhalant drug that induces a brief euphoria. See Poppers.

References

  1. ^ Noyes, W. A. “n-Butyl Nitrite” Organic Syntheses, Collected Volume 2, p.108 (1943). [1] (PDF)
  2. ^ Chen, Y. K.; Jeon, S.-J; Walsh, P. J.; Nugent, W. A. “(2S)-(-)-3-exo-(Morpholino)isoborneol ((-)-MIB)” Organic Syntheses, Volume 82, pp. 87 (2005). [2] (PDF)
  3. ^ Nickerson, Mark, John O Parker, Thomas P Lowry, and Edward W Swenson. Isobutyl Nitrite and Related Compounds. 1st ed. San Francisco: Pharmex, Ltd, 1979. [3]PDF
  4. ^ Vale, J. A. (2001). "Cyanide Antidotes: from Amyl Nitrite to Hydroxocobalamin - Which Antidote is Best?". Toxicology. 168 (1): 37–38.
  5. ^ Cheng, L.; Goodwin, C. A.; Schully, M. F.; Kakkar, V. V.; Claeson, G. (1965). "The Effects of Nitroglycerin and Amyl Nitrite on Arteriolar and Venous Tone in the Human Forearm". Circulation. 3 (2): 755.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  • Abstract for an article in the Journal of Chemical Education (1996, volume 73, page 1127) by Richard A. Kjonaas on the use of the word "amyl".