Chinese name: p-aminobenzoic acid
English name: 4-Aminobenzoic acid
CAS: 150-13-0
EINECS: 205-753-0
Chemical formula: C7H7NO2
Molecular weight: 137.14
InChI InChI = 1 / C7H7NO2 / c8-6-3-1-5 (2-4-6) 7 (9) 10 / h1-4 H, 8 h2, (H, 9, 10)/p - 1
InChIKey ALYNCZNDIQEVRV-UHFFFAOYSA-N
Density: 1.374g/mLat 25°C(lit.)
Melting point: 187-189°C(lit.)
Boiling point: 251.96°C (rough estimate)
Flash point: 250 °C
Water solubility: 4.7g /L (20 ºC)
Steam pressure: 0Pa at 25℃
Solubility: 95% ethanol: soluble 5%, transparent to slightly hazy, colorless to yellow
Refractive index: 1.5323 (estimate)
Acidity factor: 2.50, 4.87(at 25℃)
PH value: 3.5 (5g/l, H2O, 20℃)
Storage condition: 2-8°C
Stability Stability. Incompatible with strong oxidants. Combustible. Sensitive to light and air. It may change color when exposed to light.
Sensitivity: Air & Light Sensitive
Appearance: crystalline powder
Color: White to light yellow
Odor: Odorless
Merck: 14,423
BRN: 471605
Physical and chemical properties: colorless acicular crystal. Turns pale yellow in air or light. Soluble in hot water, ether, ethyl acetate, ethanol and glacial acetic acid, insoluble in water, benzene, insoluble in petroleum ether.
Purpose:
1. Medical field: Aminobenzoic acid is a commonly used ingredient in over-the-counter medications, often used to treat symptoms such as headaches, fever, and arthritis.
2. Cosmetics: Aminobenzoic acid can be used as a sunscreen ingredient in cosmetics, which has the effect of preventing ultraviolet damage.
3. Dyes and pigments industry: aminobenzoic acid is often used in synthetic dyes and pigments, for dyeing textiles, leather and paint materials.
Preparation:
Aminobenzoic acid can be obtained by reducing nitrobenzoic acid. Specific methods include:
1. Nitrobenzoic acid is reacted with reducing agents, such as sulfites or iron powder, under appropriate conditions to obtain aminobenzoic acid.
2. Alternatively, nitrobenzoic acid is reacted with reducing metals (such as iron, zinc, etc.) under acidic conditions.