O-Anisidine

o-Anisidine
Skeletal formula of o-anisidine
Ball-and-stick model of the o-anisidine molecule
Names
Preferred IUPAC name
2-Methoxyaniline[1]
Other names
ortho-Anisidine
2-Anisidine
ortho-Aminoanisole
o-Methoxyaniline
2-Methoxy-1-aminobenzene
2-Methoxyphenylamine
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.001.785 Edit this at Wikidata
EC Number
  • 201-963-1
KEGG
RTECS number
  • BZ5410000
UNII
UN number 2431
  • InChI=1S/C7H9NO/c1-9-7-5-3-2-4-6(7)8/h2-5H,8H2,1H3 checkY
    Key: VMPITZXILSNTON-UHFFFAOYSA-N checkY
  • InChI=1/C7H9NO/c1-9-7-5-3-2-4-6(7)8/h2-5H,8H2,1H3
  • Nc1ccccc1OC
Properties[2]
C7H9NO
Molar mass 123.155 g·mol−1
Appearance Yellow liquid, turns brown upon exposure to air
Density 1.0923 g/cm3
Melting point 6.2 °C (43.2 °F; 279.3 K)
Boiling point 224 °C (435 °F; 497 K)
1.5 g/100 ml
Solubility soluble in ethanol, diethyl ether, acetone, benzene
-80.44·10−6 cm3/mol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 potential occupational carcinogen[3]
GHS labelling:
GHS06: ToxicGHS08: Health hazard
Danger
H301, H311, H331, H341, H350
P201, P202, P261, P264, P270, P271, P280, P281, P301+P310, P302+P352, P304+P340, P308+P313, P311, P312, P321, P322, P330, P361, P363, P403+P233, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
1
0
Flash point 118 °C (244 °F; 391 K) (open cup)
415 °C (779 °F; 688 K)
Lethal dose or concentration (LD, LC):
2000 mg/kg (rat, oral)
1400 mg/kg (mouse, oral)
870 mg/kg (rabbit, oral)[4]
NIOSH (US health exposure limits):
PEL (Permissible)
 TWA 0.5 mg/m3 [skin][3]
REL (Recommended)
 : Ca TWA 0.5 mg/m3 [skin][3]
IDLH (Immediate danger)
 50 mg/m3[3]
Related compounds
Related compounds
 m-Anisidine
p-Anisidine
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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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.

Production and use

It is prepared via methanolysis of 2-chloronitrobenzene:[5]

NaOCH3 + ClC6H4NO2 → CH3OC6H4NO2 + NaCl

The resulting o-nitroanisole is reduced to o-anisidine.

o-Anisidine is used in the manufacture of dyes. It is nitrated to give 4-nitroanisidine. It is also a precursor to o-dianisidine.

One special use is as a heartwood indicator. An acid solution of o-anisidine is diazotized by adding a sodium nitrite solution. This mixture is applied to the wood and by reaction with polyphenols in the heartwood a reddish brown azo dye is formed.

Direct Blue 15 is an azo dye produced from o-anisidine

Safety and environmental aspects

o-Anisidine is a dangerous pollutant from the production of dyes. It is listed as RCRA hazardous waste, with the code K181.[6] The International Agency for Research on Cancer (IARC) has classified o-anisidine as a Group 2B, possible human carcinogen.[7]

References

  1. ^ Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. p. 669. doi:10.1039/9781849733069-00648. ISBN 978-0-85404-182-4. The names 'toluidine', 'anisidine', and 'phenetidine' for which o-, m-, and p- have been used to distinguish isomers, and 'xylidine' for which numerical locants, such as 2,3-, have been used, are no longer recommended, nor are the corresponding prefixes 'toluidine', 'anisidino', 'phenetidine', and 'xylidino'.
  2. ^ Weast, Robert C., ed. (1981). CRC Handbook of Chemistry and Physics (62nd ed.). Boca Raton, Florida: CRC Press. p. C-98. ISBN 0-8493-0462-8.
  3. ^ a b c d NIOSH Pocket Guide to Chemical Hazards. "#0034". National Institute for Occupational Safety and Health (NIOSH).
  4. ^ "o-Anisidine". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  5. ^ Gerald Booth (2007). "Nitro Compounds, Aromatic". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a17_411. ISBN 978-3527306732.
  6. ^ "Hazardous Waste". 2015-07-23.
  7. ^ "o-Anisidine".