:2-Nitroaniline

{{chembox

| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 477214789

| Name = 2-Nitroaniline

| ImageFileL1 = 2-nitroaniline chemical structure.png

| ImageSizeL1 = 130

| ImageAltL1 = Skeletal formula of 2-nitroaniline

| ImageFileR1 = 2-Nitroaniline-3D-balls.png

| ImageSizeR1 = 130

| ImageAltR1 = Ball-and-stick model of the 2-nitroaniline molecule

| ImageName = 2-Nitroaniline

| PIN = 2-Nitroaniline

| SystematicName = 2-Nitrobenzenamine

| OtherNames = ortho-Nitroaniline
o-Nitroaniline

|Section1={{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo = 88-74-4

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 274009

| ChemSpiderID = 13853943

| PubChem = 6946

| EC_number = 201-855-4

| RTECS = BY6650000

| UNNumber = 1661

| UNII = 2519U0541L

| SMILES = O=[N+]([O-])c1ccccc1N

| InChI = 1/C6H6N2O2/c7-5-3-1-2-4-6(5)8(9)10/h1-4H,7H2

| InChIKey = DPJCXCZTLWNFOH-UHFFFAOYAV

| StdInChI_Ref = {{stdinchicite|changed|chemspider}}

| StdInChI = 1S/C6H6N2O2/c7-5-3-1-2-4-6(5)8(9)10/h1-4H,7H2

| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}

| StdInChIKey = DPJCXCZTLWNFOH-UHFFFAOYSA-N

}}

|Section2={{Chembox Properties

| C=6 | H=6 | N=2 | O=2

| Appearance = Orange solid

| Density = 1.442 g/ml

| MeltingPtC = 71.5

| BoilingPtC = 284

| Solubility = 0.117 g/100 ml (20°C) (SIDS)

| pKa = −0.3 (of anilinium salt)

| MagSus = −66.47·10−6 cm3/mol

}}

|Section7={{Chembox Hazards

| GHSPictograms = {{GHS06}}{{GHS08}}

| GHSSignalWord = Danger

| HPhrases = {{H-phrases|301|311|331|373|412}}

| PPhrases = {{P-phrases|260|261|264|270|271|273|280|301+310|302+352|304+340|311|312|314|321|322|330|361|363|403+233|405|501}}

| FlashPtC = 168

}}

|Section8={{Chembox Related

| OtherCompounds = 3-Nitroaniline, 4-Nitroaniline

}}

}}

2-Nitroaniline is an organic compound with the formula H2NC6H4NO2. It is a derivative of aniline, carrying a nitro functional group in position 2.{{cite web |url=http://msds.chem.ox.ac.uk/NI/o-nitroaniline.html |title=Safety data for o-nitroaniline |access-date=2011-01-17 |archive-date=2009-06-28 |archive-url=https://web.archive.org/web/20090628152854/http://msds.chem.ox.ac.uk/NI/o-nitroaniline.html |url-status=dead }} It is mainly used as a precursor to o-phenylenediamine.

Synthesis

2-Nitroaniline is prepared commercially by the reaction of 2-nitrochlorobenzene with ammonia:

:ClC6H4NO2 + 2 NH3 → H2NC6H4NO2 + NH4Cl

Many other methods exist for the synthesis of this compound. Direct nitration of aniline is inefficient since anilinium is produced instead. Nitration of acetanilide gives only traces of 2-nitro isomer is obtained due to the great steric effect of the amide. Sulfonation is usually used to block the 4 position and increases the effectiveness to 56%.{{cite book|title=Organic chemistry|last1=T. W. Grahan|first1=Solomons|last2=Craig|first2=B. Fryhle|last3=Scott|first3=A. Snyder|year=2011|isbn=978-1119077251|edition= 11|pages= 606–607|publisher=John Wiley & Sons }}{{cite journal |author=Louis Ehrenfeld, Milton Puterbaugh|doi=10.15227/orgsyn.009.0064|title=o-Nitrianiline|journal=Organic Syntheses|year=1929|volume=9|page=64}}

File:2-nitroaniline synthesis.svg

Uses and reactions

2-Nitroaniline is the main precursor to phenylenediamines, which are converted to benzimidazoles, a family of heterocycles that are key components in pharmaceuticals.{{Ullmann|author=Gerald Booth|title=Nitro Compounds, Aromatic|year=2007|doi=10.1002/14356007.a17_411}}

File:O-Nitroanilin_Wasserstoffbrücke.svg

Aside from its reduction to phenylenediamine, 2-nitroaniline undergoes other reactions anticipated for aromatic amines. It is protonated to give the anilinium salts. Owing to the influence of the nitro substituent, the amine exhibits a basicity nearly 100,000x lower than aniline itself. Diazotization gives diazonium derivative,{{cite journal|title=1,2,3-Benzothiadiazole 1,1-Dioxide|author1=G. Wittig |author2=R. W. Hoffmann|journal=Org. Synth.|year=1967|volume=47|page=4|doi=10.15227/orgsyn.047.0004}} which is a precursor to some diazo dyes. Acetylation affords 2-nitroacetanilide.

See also

References

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