Nitrobenzene

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Nitrobenzene
Nitrobenzene, distances in picometers PhNO2&metric.png
Nitrobenzene, distances in picometers
Nitrobenzene Nitrobenzene-3D-vdW.png
Nitrobenzene
Sample of Nitrobenzene.jpg
Names
Preferred IUPAC name
Nitrobenzene
Other names
Nitrobenzol
Nitritebenzene
Oil of mirbane
Identifiers
3D model (JSmol)
507540
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.002.469 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 202-716-0
50357
KEGG
PubChem CID
RTECS number
  • DA6475000
UNII
  • InChI=1S/C6H5NO2/c8-7(9)6-4-2-1-3-5-6/h1-5H Yes check.svgY
    Key: LQNUZADURLCDLV-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C6H5NO2/c8-7(9)6-4-2-1-3-5-6/h1-5H
    Key: LQNUZADURLCDLV-UHFFFAOYAA
  • c1ccc(cc1)[N+](=O)[O-]
Properties
C6H5NO2
Molar mass 123.11 g/mol
Appearanceyellowish, oily liquid [1]
Odor pungent, like paste shoe polish [1] to almond-like
Density 1.199 g/cm3
Melting point 5.7 °C (42.3 °F; 278.8 K)
Boiling point 210.9 °C (411.6 °F; 484.0 K)
0.19 g/100 ml at 20 °C
Vapor pressure 0.3 mmHg (25°C) [1]
-61.80·10−6 cm3/mol
1.5215
Viscosity 1.8112 mPa·s [2]
Hazards
GHS labelling:
GHS-pictogram-skull.svg GHS-pictogram-silhouette.svg
Danger
H301, H311, H331, H351, H360, H372, H412
P201, P202, P260, P261, P264, P270, P271, P273, P280, P281, P301+P310, P302+P352, P304+P340, P308+P313, P311, P312, P314, P321, P322, P330, P361, P363, P403+P233, P405, P501
NFPA 704 (fire diamond)
NFPA 704.svgHealth 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 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g. calciumSpecial hazards (white): no code
3
2
1
Flash point 88 °C (190 °F; 361 K)
480 °C (896 °F; 753 K)
Explosive limits 1.8%-? [1]
Lethal dose or concentration (LD, LC):
780 mg/kg (rat, oral)
600 mg/kg (rat, oral)
590 mg/kg (mouse, oral)
[3]
750 mg/kg (dog, oral) [3]
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 1 ppm (5 mg/m3) [skin] [1]
REL (Recommended)
TWA 1 ppm (5 mg/m3) [skin] [1]
IDLH (Immediate danger)
200 ppm [1]
Related compounds
Related compounds
 Aniline
Benzenediazonium chloride
Nitrosobenzene
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Nitrobenzene is an aromatic nitro compound and the simplest of the nitrobenzenes, with the chemical formula C6H5 NO2. It is a water-insoluble pale yellow oil with an almond-like odor. It freezes to give greenish-yellow crystals. It is produced on a large scale from benzene as a precursor to aniline. In the laboratory, it is occasionally used as a solvent, especially for electrophilic reagents. As confirmed by X-ray crystallography, nitrobenzene is a planar molecule. [4]

Contents

Production

Nitrobenzene is prepared by nitration of benzene with a mixture of concentrated sulfuric acid, water, and nitric acid. This mixture is sometimes called "mixed acid." The production of nitrobenzene is one of the most dangerous processes conducted in the chemical industry because of the exothermicity of the reaction (ΔH = −117 kJ/mol). [5]

Benzol.svg + Nitronium ion vert.svg
 
 H+
Biochem reaction arrow forward NYNN horiz med.svg
Nitrobenzol.svg

World capacity for nitrobenzene in 1985 was about 1,700,000 tonnes. [5]

The nitration process involves formation of the nitronium ion (NO2+), followed by an electrophilic aromatic substitution reaction of it with benzene. The nitronium ion is generated by the reaction of nitric acid and an acidic dehydration agent, typically sulfuric acid:

HNO3 + H+⇌ NO2+ + H2O

Uses

Approximately 95% of nitrobenzene industrially produced is hydrogenated to aniline: [5]

C6H5NO2 + 3 H2 → C6H5NH2 + 2 H2O

Aniline is a precursor to urethane polymers, rubber chemicals, pesticides, dyes (particularly azo dyes), explosives, and pharmaceuticals.

Most aniline is consumed in the production of methylenedianiline, a precursor to polyurethanes. Synthesis of 4,4'-diaminodiphenylmethane.svg
Most aniline is consumed in the production of methylenedianiline, a precursor to polyurethanes.

Specialized applications

Nitrobenzene is used to mask unpleasant odors in shoe and floor polishes, leather dressings, paint solvents, and other materials. Redistilled, as oil of mirbane, nitrobenzene had been used as an inexpensive perfume for soaps. It has been replaced by less toxic chemicals for this purpose. [6] A significant merchant market for nitrobenzene is its use in the production of the analgesic paracetamol (also known as acetaminophen). [7] Nitrobenzene is also used in Kerr cells, as it has an unusually large Kerr constant. Evidence suggests its use in agriculture as a plant growth/flowering stimulant. [8]

Organic reactions

Aside from its conversion to aniline, nitrobenzene can be selectively reduced to azoxybenzene, [9] azobenzene, [10] nitrosobenzene, [11] hydrazobenzene, [12] and phenylhydroxylamine. [13] It has been used as a mild oxidant in reactions like the Skraup quinoline synthesis. [14]

Safety

Nitrobenzene is highly toxic (Threshold Limit Value 5 mg/m3) and readily absorbed through the skin.

Prolonged exposure may cause serious damage to the central nervous system, impair vision, cause liver or kidney damage, anemia and lung irritation. Inhalation of vapors may induce headache, nausea, fatigue, dizziness, cyanosis, weakness in the arms and legs, and in rare cases may be fatal. The oil is readily absorbed through the skin and may increase heart rate, cause convulsions or rarely death. Ingestion may similarly cause headaches, dizziness, nausea, vomiting and gastrointestinal irritation, loss of sensation/use in limbs and also causes internal bleeding. [11]

Nitrobenzene is considered a likely human carcinogen by the United States Environmental Protection Agency, [15] and is classified by the IARC as a Group 2B carcinogen which is "possibly carcinogenic to humans". [16] It has been shown to cause liver, kidney, and thyroid adenomas and carcinomas in rats. [17]

It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities. [18]

Related Research Articles

<span class="mw-page-title-main">Naphthalene</span> Chemical compound

Naphthalene is an organic compound with formula C
10H
8. It is the simplest polycyclic aromatic hydrocarbon, and is a white crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass. As an aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings. It is the main ingredient of traditional mothballs.

<span class="mw-page-title-main">Aniline</span> Organic compound (C₆H₅NH₂); simplest aromatic amine

Aniline is an organic compound with the formula C6H5NH2. Consisting of a phenyl group attached to an amino group, aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans.

Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen atom. Chemical compounds containing such rings are also referred to as furans.

<span class="mw-page-title-main">Phenanthrene</span> Polycyclic aromatic hydrocarbon composed of three fused benzene rings

Phenanthrene is a polycyclic aromatic hydrocarbon (PAH) with formula C14H10, consisting of three fused benzene rings. It is a colorless, crystal-like solid, but can also appear yellow. Phenanthrene is used to make dyes, plastics, pesticides, explosives, and drugs. It has also been used to make bile acids, cholesterol and steroids.

<span class="mw-page-title-main">Nitration</span> Chemical reaction which adds a nitro (–NO₂) group onto a molecule

In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group into an organic compound. The term also is applied incorrectly to the different process of forming nitrate esters between alcohols and nitric acid. The difference between the resulting molecular structures of nitro compounds and nitrates is that the nitrogen atom in nitro compounds is directly bonded to a non-oxygen atom, whereas in nitrate esters, the nitrogen is bonded to an oxygen atom that in turn usually is bonded to a carbon atom.

<span class="mw-page-title-main">Nitro compound</span> Organic compound containing an −NO₂ group

In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups. The nitro group is one of the most common explosophores used globally. The nitro group is also strongly electron-withdrawing. Because of this property, C−H bonds alpha (adjacent) to the nitro group can be acidic. For similar reasons, the presence of nitro groups in aromatic compounds retards electrophilic aromatic substitution but facilitates nucleophilic aromatic substitution. Nitro groups are rarely found in nature. They are almost invariably produced by nitration reactions starting with nitric acid.

<span class="mw-page-title-main">Ethylbenzene</span> Hydrocarbon compound; precursor to styrene and polystyrene

Ethylbenzene is an organic compound with the formula C6H5CH2CH3. It is a highly flammable, colorless liquid with an odor similar to that of gasoline. This monocyclic aromatic hydrocarbon is important in the petrochemical industry as a reaction intermediate in the production of styrene, the precursor to polystyrene, a common plastic material. In 2012, more than 99% of ethylbenzene produced was consumed in the production of styrene.

The Skraup synthesis is a chemical reaction used to synthesize quinolines. It is named after the Czech chemist Zdenko Hans Skraup (1850-1910). In the archetypal Skraup reaction, aniline is heated with sulfuric acid, glycerol, and an oxidizing agent such as nitrobenzene to yield quinoline.

<span class="mw-page-title-main">1,4-Benzoquinone</span> Chemical compound

1,4-Benzoquinone, commonly known as para-quinone, is a chemical compound with the formula C6H4O2. In a pure state, it forms bright-yellow crystals with a characteristic irritating odor, resembling that of chlorine, bleach, and hot plastic or formaldehyde. This six-membered ring compound is the oxidized derivative of 1,4-hydroquinone. The molecule is multifunctional: it exhibits properties of a ketone, being able to form oximes; an oxidant, forming the dihydroxy derivative; and an alkene, undergoing addition reactions, especially those typical for α,β-unsaturated ketones. 1,4-Benzoquinone is sensitive toward both strong mineral acids and alkali, which cause condensation and decomposition of the compound.

<span class="mw-page-title-main">Benzidine</span> Chemical compound

Benzidine (trivial name), also called 1,1'-biphenyl-4,4'-diamine (systematic name), is an organic compound with the formula (C6H4NH2)2. It is an aromatic amine. It is a component of a test for cyanide. Related derivatives are used in the production of dyes. Benzidine has been linked to bladder and pancreatic cancer.

<span class="mw-page-title-main">Azoxy compounds</span> Chemical compound of the form R–N=N(–O)–R

In chemistry, azoxy compounds are a group of organic compounds sharing a common functional group with the general structure R−N=N+(−O−)−R. They are considered N-oxides of azo compounds. Azoxy compounds are 1,3-dipoles and cycloadd to double bonds. Most azoxy-containing compounds have aryl substituents.

<span class="mw-page-title-main">Nitrosobenzene</span> Chemical compound

Nitrosobenzene is the organic compound with the formula C6H5NO. It is one of the prototypical organic nitroso compounds. Characteristic of its functional group, it is a dark green species that exists in equilibrium with its pale yellow dimer. Both monomer and dimer are diamagnetic.

<span class="mw-page-title-main">4-Aminophenol</span> Chemical compound

4-Aminophenol (or para-aminophenol or p-aminophenol) is an organic compound with the formula H2NC6H4OH. Typically available as a white powder, it is commonly used as a developer for black-and-white film, marketed under the name Rodinal.

The Blanc chloromethylation is the chemical reaction of aromatic rings with formaldehyde and hydrogen chloride to form chloromethyl arenes. The reaction is catalyzed by Lewis acids such as zinc chloride. The reaction was discovered by Gustave Louis Blanc (1872-1927) in 1923.

The Béchamp reduction is a chemical reaction that converts aromatic nitro compounds to their corresponding anilines using iron as the reductant:

<span class="mw-page-title-main">4-Nitroaniline</span> Chemical compound

4-Nitroaniline, p-nitroaniline or 1-amino-4-nitrobenzene is an organic compound with the formula C6H6N2O2. A yellow solid, it is one of three isomers of nitroaniline. It is an intermediate in the production of dyes, antioxidants, pharmaceuticals, gasoline, gum inhibitors, poultry medicines, and as a corrosion inhibitor.

<i>o</i>-Anisidine Chemical compound

o-Anisidine (2-anisidine) is an organic compound with the formula CH3OC6H4NH2. A colorless liquid, commercial samples can appear yellow owing to air oxidation. It is one of three isomers of the methoxy-containing aniline derivative.

<span class="mw-page-title-main">Benzene</span> Hydrocarbon compound

Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon.

<span class="mw-page-title-main">4-Nitrochlorobenzene</span> Chemical compound

4-Nitrochlorobenzene is the organic compound with the formula ClC6H4NO2. It is a pale yellow solid. 4-Nitrochlorobenzene is a common intermediate in the production of a number of industrially useful compounds, including antioxidants commonly found in rubber. Other isomers with the formula ClC6H4NO2 include 2-nitrochlorobenzene and 3-nitrochlorobenzene.

4-Nitrotoluene or para-nitrotoluene is an organic compound with the formula CH3C6H4NO2. It is a pale yellow solid. It is one of three isomers of nitrotoluene.

References

  1. 1 2 3 4 5 6 7 NIOSH Pocket Guide to Chemical Hazards. "#0450". National Institute for Occupational Safety and Health (NIOSH).
  2. ↑ Ahluwalia, R.; Wanchoo, R. K.; Sharma, S. K.; Vashisht, J. L. (1996). "Density, viscosity, and surface tension of binary liquid systems: Ethanoic acid, propanoic acid, and butanoic acid with nitrobenzene". Journal of Solution Chemistry. 25 (9): 905–917. doi:10.1007/BF00972581. ISSN   0095-9782. S2CID   95126469.
  3. 1 2 "Nitrobenzene". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  4. ↑ Olga V. Dorofeeva; Yuriy V. Vishnevskiy; Natalja Vogt; Jürgen Vogt; Lyudmila V. Khristenko; Sergey V. Krasnoshchekov; Igor F. Shishkov; István Hargittai; Lev V. Vilkov (2007). "Molecular Structure and Conformation of Nitrobenzene Reinvestigated by Combined Analysis of Gas-Phase Electron Diffraction, Rotational Constants, and Theoretical Calculations". Structural Chemistry. 18 (6): 739–753. doi:10.1007/s11224-007-9186-6. S2CID   98746905.
  5. 1 2 3 Booth G (2007). "Nitro Compounds, Aromatic". Ullmann's Encyclopedia of Industrial Chemistry (6th ed.). Weinheim: Wiley-VCH. doi:10.1002/14356007.a17_411. ISBN   978-3-527-30385-4.
  6. ↑ Hogarth CW (January 1912). "a case of poisoning by oil of mirbane (nitro-benzol)". British Medical Journal. 1 (2665): 183. doi:10.1136/bmj.1.2665.183. PMC   2344391 . PMID   20765985.
  7. ↑ Bhattacharya A, Purohit VC, Suarez V, Tichkule R, Parmer G, Rinaldi F (March 2006). "One-step reductive amidation of nitro arenes: application in the synthesis of Acetaminophen". Tetrahedron Letters. 47 (11): 1861–1864. doi:10.1016/j.tetlet.2005.09.196.
  8. ↑ "Flowering stimulant composition using nitrobenzene".
  9. ↑ Bigelow, H. E.; Palmer, Albert (1931). "Azoxybenzene". Organic Syntheses. 11: 16. doi:10.15227/orgsyn.011.0016.
  10. ↑ Bigelow HE, Robinson DB (1955). "Azobenzene". Organic Syntheses ; Collected Volumes, vol. 3, p. 103.
  11. 1 2 Coleman GH, McCloskey CM, Stuart FA. "Nitrosobenzene". Organic Syntheses ; Collected Volumes, vol. 3, p. 668.
  12. ↑ Karwa, Shrikant L.; Rajadhyaksha, Rajeev A. (January 1988). "Selective catalytic hydrogenation of nitrobenzene to hydrazobenzene". Industrial & Engineering Chemistry Research. 27 (1): 21–24. doi:10.1021/ie00073a005. ISSN   0888-5885.
  13. ↑ Kamm O. "β-Phenylhydroxylamine". Organic Syntheses ; Collected Volumes, vol. 1, p. 445.
  14. ↑ Clarke, HT; Davis, AW. "Quinoline". Organic Syntheses. 1: 478.
  15. ↑ Division, US EPA, ORD, Integrated Risk Information System. "Nitrobenzene CASRN 98-95-3 - IRIS - US EPA, ORD". cfpub.epa.gov. Retrieved 10 August 2017.{{cite web}}: CS1 maint: multiple names: authors list (link)
  16. ↑ "Agents Classified by the IARC Monographs, International Agency for Research on Cancer" (PDF). Retrieved 10 August 2017.
  17. ↑ National Institutes of Health · U.S. Department of Health and Human Services, Nomination: Nitrobenzene Review committee, 02/02/2010
  18. ↑ "40 C.F.R.: Appendix A to Part 355—The List of Extremely Hazardous Substances and Their Threshold Planning Quantities" (PDF) (July 1, 2008 ed.). Government Printing Office. Archived from the original (PDF) on February 25, 2012. Retrieved October 29, 2011.
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