p-Anisidine Chemical Properties

Melting point:

56-59 °C(lit.)

Boiling point:

240-243 °C(lit.)

Density 

1.06

vapor density 

4.28

vapor pressure 

0.02 hPa (20 °C)

refractive index 

1.5559

Flash point:

122 °C

storage temp. 

Store below +30°C.

solubility 

21g/l

pka

5.34(at 25℃)

form 

crystalline

color 

dark gray to brown

Specific Gravity

1.07

PH

7.7 (1g/l, H2O, 20℃)

Water Solubility 

21 g/L (20 ºC)

Merck 

14,667

BRN 

471556

Henry's Law Constant

(x 10^-8 atm?m³/mol): 6.62 at 25 °C (thermodynamic method-GC/UV spectrophotometry, Altschuh et al., 1999)

Exposure limits

NIOSH REL: TWA 0.5 mg/m³, IDLH 50 mg/m³; OSHA PEL: TWA 0.5 mg/m³; ACGIH TLV: TWA 0.1 ppm (adopted).

Dielectric constant

8.8399999999999999

Stability:

Hygroscopic, Material Darkens In Storage With No Loss In Purity

LogP

0.950

CAS DataBase Reference

104-94-9(CAS DataBase Reference)

IARC

3 (Vol. 27, Sup 7) 1987

NIST Chemistry Reference

Benzenamine, 4-methoxy-(104-94-9)

EPA Substance Registry System

p-Anisidine (104-94-9)

Safety Information

Hazard Codes 

T+,N,Xi

Risk Statements 

45-26/27/28-33-50

Safety Statements 

53-28-36/37-45-61-28A

OEB

C

OEL

TWA: 0.5 mg/m3 [skin]

RIDADR 

UN 2811 6.1/PG 3

WGK Germany 

2

RTECS 

BZ5450000

F 

8

Autoignition Temperature

959 °F

TSCA 

Yes

HazardClass 

6.1

PackingGroup 

III

HS Code 

29222200

Hazardous Substances Data

104-94-9(Hazardous Substances Data)

Toxicity

Acute oral LD₅₀ for rats 1,400 mg/kg, mice 810 mg/kg, rabbits 2,900 mg/kg (quoted, RTECS, 1985).

IDLA

50 mg/m3

MSDS

• Language:English Provider:4-Methoxybenzeneamine
• Language:English Provider:SigmaAldrich
• Language:English Provider:ACROS
• Language:English Provider:ALFA

p-Anisidine Usage And Synthesis

Anisidine value

Anisidine value (AV) is a measure of the aldehyde levels in an oil or fat, in particular those that are unsaturated (and principally the 2–alkenals). To determine AV, a solution of the oil or fat in iso-octane is reacted with p-anisidine in glacial acetic acid to form yellowish reaction proucts. The AV is then determined from the absorbance measured at 350 nm, both before and after reaction.

Chemical Properties

Anisidine exists as ortho-, meta-, and paraisomers. They have characteristic amine (fishy) odors. releases toxic nitrogen oxides when heated to decomposition (Sax and Lewis, 1987).

Physical properties

Yellow to light brown powder, leaflets, solid or crystals with a characteristic amine or ammonialike odor. soluble in ethanol and ether, slightly soluble in water.

Uses

p-Anisidine is used mostly for producing dyes, and some smaller quantities are employed in making pharmaceuticals and liquid crystals.

Definition

ChEBI: P-anisidine is a substituted aniline that is aniline in which the hydrogen para to the amino group has been replaced by a methoxy group. It is used as a reagent for the detection of oxidation products such as aldehydes and ketones in fats and oils. It has a role as a reagent and a genotoxin. It is a member of methoxybenzenes, a substituted aniline and a primary amino compound.

Application

p-Anisidine is used as a reagent to indicate the secondary stage of the oxidation, it is one of the three possible isomers of the Anisidine or methoxyaniline. The other two isomers are o-Anisidine (2-methoxyaniline) and m-Anisidine (3-methoxyaniline).
The p-anisidine is widely used as an intermediate in the production of numerous azo and triphenylmethane dyes, and pigments. It is also used in the production of pharmaceuticals including the guaiacol expectorant, as an antioxidant for polymercaptan resins, and as a corrosion inhibitor for steel. Apart from the beneficial use of p-anisidine, it is toxic for human beings. The acute exposure may cause skin irritation, whereas the chronic exposure may cause headaches, vertigo, and blood complications like sulfhemoglobin, and methemoglobin. The oral exposure to anisidine hydrochloride resulted in cancer of the urinary bladder in male and female rats.
https://www.longdom.org/open-access/physicochemical-and-spectroscopic-characterization-of-biofield-energytreated-panisidine-paco-1000102.pdf

Preparation

p-Anisidine is an important intermediate for synthesis of dye, medicine and perfume. Traditional preparation of p-Anisidine uses iron powder or sodium sulfide as reductant, which produces a large amount of waste and results in serious environment pollution problem. Liquid phase catalytic hydrogenation is not only an environmentally benign technique but also of high yield.
Synthesis of p-Anisidine by Hydrogenation with Raney-RuNiC as Catalyst

Synthesis Reference(s)

Journal of the American Chemical Society, 99, p. 98, 1977 DOI: 10.1021/ja00443a018
The Journal of Organic Chemistry, 49, p. 1434, 1984 DOI: 10.1021/jo00182a023
Tetrahedron Letters, 21, p. 2603, 1980 DOI: 10.1016/S0040-4039(00)92816-8

General Description

P-anisidine appears as brown crystals or dark brown solid. Characteristic amine odor. (NTP, 1992)

Air & Water Reactions

Insoluble in water.

Reactivity Profile

p-Anisidine may be sensitive to heat, light and moisture. Reacts with acids, acid chlorides, acid anhydrides, chloroformates and strong oxidizing agents. Incompatible with alkaline materials. Incompatible with aldehydes, ketones and nitrates.

Hazard

Strong irritant. Toxic when absorbed through the skin. Questionable carcinogen.

Fire Hazard

p-Anisidine is flammable.

Safety Profile

Moderately toxic by several routes. A mild sensitizer. May cause a contact dermatitis. Mutation data reported. Questionable carcinogen. See also ANILINE. When heated to decomposition it emits toxic fumes of Nox

Potential Exposure

Anisidines are used in the manufacture of azo dyes; pharmaceuticals; textile-processing chemicals Incompatibilities: Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine,bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides. Attacks some coatings and some forms of plastic and rubber.

Carcinogenicity

Available data were inadequate to evaluate the carcinogenicity of p-anisidine.

Shipping

UN2431 Anisidines, Hazard Class: 6.1; Labels: 6.1-Poisonous materials

Purification Methods

Crystallise p-anisidine from H2O or aqueous EtOH. Dry it in a vacuum oven at 35o for 6hours and store it in a dry box. [More et al. J Am Chem Soc 108 2257 1986.] Purify it also by vacuum sublimation [Guarr et al. J Am Chem Soc 107 5104 1985]. [Beilstein 13 IV 1015.]

Waste Disposal

Dissolve in combustible solvent (alcohols, benzene, etc.) and spray solution into furnace equipped with afterburner and scrubber, or burn spill residue on sand and soda ash absorbent in a furnace.

p-Anisidine(104-94-9)Related Product Information

• Sulfanilic acid
• Benzocaine
• m-Anisidine
• p-Anisidine-3-sulfonic acid
• Anise oil
• 4-Amino-benzenesulfonic acid monosodium salt
• 4-(Trifluoromethoxy)aniline
• 4-Methoxyphenylacetic acid
• 4-Aminophenylacetic acid
• 4-Methoxybenzoic acid
• 4-Aminoveratrole
• o-Dianisidine
• 4-Aminobenzoic acid
• 2,4-DIAMINOANISOLE
• 4-Dimethylaminobenzoic acid
• 4-Aminobenzaldehyde
• 3-Ethoxyaniline
• 4-Methoxybenzyl alcohol