2-Nitrochlorobenzene

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.

2-Nitrochlorobenzene

Names
Preferred IUPAC name 1-Chloro-2-nitrobenzene
Other names 2-Chloronitrobenzene
Identifiers
CAS Number	88-73-3
3D model (JSmol)	Interactive image
ChEBI	CHEBI:34270
ChEMBL	ChEMBL53330
ChemSpider	13853953
ECHA InfoCard	100.001.686
EC Number	201-854-9
KEGG	C14407
PubChem CID	6945
RTECS number	CZ0875000
UNII	D1YI9R2K8O
UN number	1578
CompTox Dashboard (EPA)	DTXSID0020280
InChI 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
SMILES C1=CC=C(C(=C1)[N+](=O)[O-])Cl
Properties
Chemical formula	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)
Solubility in water	Insoluble
Solubility in other solvents	Highly soluble in diethyl ether, benzene, and hot ethanol
Hazards
Main hazards	Toxic, Irritant
GHS pictograms
GHS Signal word	Danger
GHS hazard statements	H301, H302, H311, H312, H317, H331, H332, H350, H351, H361, H372, H411
GHS precautionary statements	P201, P202, P260, P261, P264, P270, P271, P272, P273, P280, P281, P301+310, P301+312, P302+352, P304+312, P304+340, P308+313, P311, P312, P314, P321, P322, P330, P333+313, P361
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).
Infobox references

Synthesis

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 30/56/14, the product mix is typically 34-36% 2-nitrochlorobenzene and 63-65% 4-nitrochlorobenzene, with only about 1% 3-nitrochlorobenzene.

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.[1] 2-Nitrochlorobenzene can be reduced to the 2-chloroaniline with Fe/HCl mixture, the Bechamp reduction. Treatment of 2-nitrochlorobenzene with sodium methoxide gives 2-nitroanisole.

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.

It is used in the synthesis of quetiapine & Clotiapine.

References

1. Gerald Booth, "Nitro Compounds, Aromatic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH: Weinheim, 2005. doi:10.1002/14356007.a17_411