Jump to content

2-Nitrochlorobenzene: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
OS ref
tidy up some of my own excessive language
 
(4 intermediate revisions by 4 users not shown)
Line 1: Line 1:
{{Chembox
{{Chembox
| ImageFile = 1-chloor-2-nitrobenzeen.png
| ImageFile = 2-Chlornitrobenzol.svg
| ImageSize = 150px
| ImageSize = 150px
| PIN = 1-Chloro-2-nitrobenzene
| PIN = 1-Chloro-2-nitrobenzene
Line 41: Line 41:
}}
}}


'''2-Nitrochlorobenzene''' is an [[organic compound]] with the formula ClC<sub>6</sub>H<sub>4</sub>NO<sub>2</sub>. It is one of three isomeric [[nitrochlorobenzene]]s.<ref name=Ullmann>Gerald Booth, "Nitro Compounds, Aromatic" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH: Weinheim, 2005. {{doi|10.1002/14356007.a17_411}}</ref> It is a yellow crystalline solid that is important as a precursor to other compounds due to its two functional groups.
'''2-Nitrochlorobenzene''' is an [[organic compound]] with the formula ClC<sub>6</sub>H<sub>4</sub>NO<sub>2</sub>. It is one of three isomeric [[nitrochlorobenzene]]s.<ref name=Ullmann>{{cite book|doi=10.1002/14356007.a17_411 |chapter=Nitro Compounds, Aromatic |title=Ullmann's Encyclopedia of Industrial Chemistry |date=2000 |last1=Booth |first1=Gerald |isbn=978-3-527-30385-4|publisher= Wiley-VCH|location=Weinheim}}</ref> It is a yellow crystalline solid that is important as a precursor to other compounds due to its two functional groups.


==Synthesis==
==Synthesis==
Line 47: Line 47:
:C<sub>6</sub>H<sub>5</sub>Cl + HNO<sub>3</sub> → O<sub>2</sub>NC<sub>6</sub>H<sub>4</sub>Cl + H<sub>2</sub>O
:C<sub>6</sub>H<sub>5</sub>Cl + HNO<sub>3</sub> → O<sub>2</sub>NC<sub>6</sub>H<sub>4</sub>Cl + H<sub>2</sub>O


This reaction affords a mixture of isomers. Using an acid ratio of 30% nitric acid, 56% sulfuric acid and 14% water, the product mix is typically 34-36% 2-nitrochlorobenzene and 63-65% [[4-nitrochlorobenzene]], with only about 1% [[3-nitrochlorobenzene]].
This reaction affords a mixture of isomers. Using an acid ratio of 30% nitric acid, 56% sulfuric acid and 14% water, the product mix is typically 34-36% 2-nitrochlorobenzene and 63-65% [[4-nitrochlorobenzene]], with only about 1% [[3-nitrochlorobenzene]].<ref name=Ullmann/>


==Reactions==
==Reactions==
Alkylation and electrophilic aromatic substitution can occur at the chlorinated carbon center, and a diverse array of reactions can be carried out using the nitro group.<ref name=Ullmann/> 2-Nitrochlorobenzene can be reduced to the [[chloroaniline|2-chloroaniline]] with Fe/HCl mixture, the [[Bechamp reduction]].
2-Nitrochlorobenzene can be reduced to the [[chloroaniline|2-chloroaniline]] with Fe/HCl mixture, the [[Bechamp reduction]].<ref name=Ullmann/>


2-Nitrochlorobenzene, like its isomers, is reactive toward nucleophiles, resulting in chloride substitution. With [[polysulfide]], it reacts to give di-orthonitrophenyl disulfide:<ref>{{cite journal |doi=10.15227/orgsyn.008.0064 |title=Di-''o''-Nitrophenyl Disulfide |journal=Organic Syntheses |year=1928 |volume=8 |page=64|first1= Marston T. |last1=Bogert|first2=Arthur|last2=Stull }}</ref>
2-Nitrochlorobenzene, like its isomers, is reactive toward nucleophiles, resulting in chloride substitution. With [[polysulfide]], it reacts to give di-orthonitrophenyl disulfide:<ref>{{cite journal |doi=10.15227/orgsyn.008.0064 |title=Di-''o''-Nitrophenyl Disulfide |journal=Organic Syntheses |year=1928 |volume=8 |page=64|first1= Marston T. |last1=Bogert|first2=Arthur|last2=Stull }}</ref>
:{{chem2|2 O2NC6H4Cl + Na2S2 -> (O2NC6H4S)2 + 2 NaCl}}
:{{chem2|2 O2NC6H4Cl + Na2S2 -> (O2NC6H4S)2 + 2 NaCl}}
Similarly, it reacts with [[sodium methoxide]] to give [[O-Nitroanisole|2-nitroanisole]].
Similarly, it reacts with [[sodium methoxide]] to give [[O-Nitroanisole|2-nitroanisole]].

Substitution of chloride by fluoride is also practiced commercially to convert 2-nitrochlorobenzene to [[2-Fluoronitrobenzene|2-fluoronitrobenzene]]. The [[Halex process]] uses [[potassium fluoride]] in polar solvents like [[sulfolane]] :
:{{chem2|O2NC6H4Cl + KF -> O2NC6H4F + KCl}}


==Applications==
==Applications==
2-Nitrochlorobenzene is not valuable in itself but is a precursor to other useful compounds. The compound is particularly useful because both of its reactive sites can be utilized to create further compounds that are mutually ''ortho''. Its derivative 2-chloroaniline is a precursor to [[3,3’-dichlorobenzidine]], itself a precursor to many dyes and pesticides.
2-Nitrochlorobenzene is useful because both of its reactive sites can be utilized to create further compounds that are mutually ''ortho''. Its derivative 2-chloroaniline is a precursor to [[3,3’-dichlorobenzidine]], a precursor to dyes and pesticides.


==References==
==References==
Line 63: Line 66:


{{DEFAULTSORT:Nitrochlorobenzene, 2-}}
{{DEFAULTSORT:Nitrochlorobenzene, 2-}}
[[Category:Nitrobenzenes]]
[[Category:Nitrobenzene derivatives]]
[[Category:Chloroarenes]]
[[Category:2-Chlorophenyl compounds]]

Latest revision as of 18:27, 9 September 2024

2-Nitrochlorobenzene
Names
Preferred IUPAC name
1-Chloro-2-nitrobenzene
Other names
2-Chloronitrobenzene
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.001.686 Edit this at Wikidata
EC Number
  • 201-854-9
KEGG
RTECS number
  • CZ0875000
UNII
UN number 1578
  • InChI=1S/C6H4ClNO2/c7-5-3-1-2-4-6(5)8(9)10/h1-4H
    Key: BFCFYVKQTRLZHA-UHFFFAOYSA-N
  • InChI=1/C6H4ClNO2/c7-5-3-1-2-4-6(5)8(9)10/h1-4H
    Key: BFCFYVKQTRLZHA-UHFFFAOYAA
  • C1=CC=C(C(=C1)[N+](=O)[O-])Cl
Properties
C6H4ClNO2
Molar mass 157.55 g·mol−1
Appearance Yellow crystals
Density 1.368 g/mL
Melting point 33 °C (91 °F; 306 K)
Boiling point 245.5 °C (473.9 °F; 518.6 K)
Insoluble
Solubility in other solvents Highly soluble in diethyl ether, benzene, and hot ethanol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Toxic, Irritant
GHS labelling:
GHS06: ToxicGHS07: Exclamation markGHS08: Health hazardGHS09: Environmental hazard
Danger
H301, H302, H311, H312, H317, H331, H332, H350, H351, H361, H372, H411
P201, P202, P260, P261, P264, P270, P271, P272, P273, P280, P281, P301+P310, P301+P312, P302+P352, P304+P312, P304+P340, P308+P313, P311, P312, P314, P321, P322, P330, P333+P313, P361, P363, P391, P403+P233, P405, P501
Flash point 124 °C (255 °F; 397 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

2-Nitrochlorobenzene is an organic compound with the formula ClC6H4NO2. It is one of three isomeric nitrochlorobenzenes.[1] It is a yellow crystalline solid that is important as a precursor to other compounds due to its two functional groups.

Synthesis

[edit]

Nitrochlorobenzene is typically synthesized by nitration of chlorobenzene in the presence of sulfuric acid:

C6H5Cl + HNO3 → O2NC6H4Cl + H2O

This reaction affords a mixture of isomers. Using an acid ratio of 30% nitric acid, 56% sulfuric acid and 14% water, the product mix is typically 34-36% 2-nitrochlorobenzene and 63-65% 4-nitrochlorobenzene, with only about 1% 3-nitrochlorobenzene.[1]

Reactions

[edit]

2-Nitrochlorobenzene can be reduced to the 2-chloroaniline with Fe/HCl mixture, the Bechamp reduction.[1]

2-Nitrochlorobenzene, like its isomers, is reactive toward nucleophiles, resulting in chloride substitution. With polysulfide, it reacts to give di-orthonitrophenyl disulfide:[2]

2 O2NC6H4Cl + Na2S2 → (O2NC6H4S)2 + 2 NaCl

Similarly, it reacts with sodium methoxide to give 2-nitroanisole.

Substitution of chloride by fluoride is also practiced commercially to convert 2-nitrochlorobenzene to 2-fluoronitrobenzene. The Halex process uses potassium fluoride in polar solvents like sulfolane :

O2NC6H4Cl + KF → O2NC6H4F + KCl

Applications

[edit]

2-Nitrochlorobenzene is useful because both of its reactive sites can be utilized to create further compounds that are mutually ortho. Its derivative 2-chloroaniline is a precursor to 3,3’-dichlorobenzidine, a precursor to dyes and pesticides.

References

[edit]
  1. ^ a b c Booth, Gerald (2000). "Nitro Compounds, Aromatic". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a17_411. ISBN 978-3-527-30385-4.
  2. ^ Bogert, Marston T.; Stull, Arthur (1928). "Di-o-Nitrophenyl Disulfide". Organic Syntheses. 8: 64. doi:10.15227/orgsyn.008.0064.