Name | 4-Aminobenzoic acid |
Synonyms | PABA H-4-Abz-OH The aMino acid 4-carboxyanilin 4-aminobenzoate p-Aminobenzoic acid Folic acid Impurity 4-Aminobenzoic acid Acid 4-aminobenzoico P-amino benzoic acid 4-Aminobenzonic acid Aminobenzoic acid, 4- p-Amino Benzonic Acid Conivaptan hydrochkoride Impurity B |
CAS | 150-13-0 |
EINECS | 205-753-0 |
InChI | InChI=1/C7H7NO2/c8-6-3-1-5(2-4-6)7(9)10/h1-4H,8H2,(H,9,10)/p-1 |
InChIKey | ALYNCZNDIQEVRV-UHFFFAOYSA-N |
Molecular Formula | C7H7NO2 |
Molar Mass | 137.14 |
Density | 1.374g/mLat 25°C(lit.) |
Melting Point | 187-189°C(lit.) |
Boling Point | 251.96°C (rough estimate) |
Flash Point | 250 °C |
Water Solubility | 4.7 g/L (20 ºC) |
Solubility | ethanol: 50 mg/mL. Soluble in hot water, ether, ethyl acetate, ethanol and glacial acetic acid, insoluble in water, benzene, insoluble in petroleum ether. |
Vapor Presure | 0Pa at 25℃ |
Appearance | Colorless needle crystal |
Color | White to light yellow |
Odor | Odorless |
Merck | 14,423 |
BRN | 471605 |
pKa | 2.50, 4.87(at 25℃) |
PH | 3.5 (5g/l, H2O, 20℃) |
Storage Condition | 2-8°C |
Stability | Stable. Incompatible with strong oxidizing agents. Combustible. Sensitive to light and air. May discolour on exposure to light. |
Sensitive | Air & Light Sensitive |
Refractive Index | 1.5323 (estimate) |
MDL | MFCD00007894 |
Physical and Chemical Properties | character: colorless needle-like crystals. Turn pale yellow in air or light. |
Use | Used as pharmaceutical and dye intermediates |
Risk Codes | R22 - Harmful if swallowed R36/37/38 - Irritating to eyes, respiratory system and skin. R43 - May cause sensitization by skin contact |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36 - Wear suitable protective clothing. S37/39 - Wear suitable gloves and eye/face protection |
WGK Germany | 3 |
RTECS | DG1400000 |
TSCA | Yes |
HS Code | 29224995 |
Toxicity | LD50 in mice, rats (g/kg): 2.85, >6.0 orally (Scott, Robbins); LD50 in rabbits (g/kg): 2.0 i.v. (Richards); 1.83 orally (Cronheim) |
Raw Materials | 4-Nitrobenzoic acid 4-Nitrobenzoic acid |
Downstream Products | Methyl Orange Ethyl 4-aminobenzoate |
Reference Show more | 1. [IF=5.811] Jiang XL et al."Hepatoprotective Effect of Oplopanax elatus Nakai Adventitious Roots Extract by Regulating CYP450 and PPAR Signaling Pathway.."Frontiers in Pharmacology. 2022 May;13:761618-761618 |
colorless needle-like crystals. Melting Point 187~187.5 deg C, in the air or light to light yellow. Soluble in hot water, ether, ethyl acetate, ethanol and acetic acid, insoluble in water, benzene, insoluble in petroleum ether.
used as reactive dyes and azo dye intermediates, organic chemical and pharmaceutical (carboxyl benzyl amine) raw materials, Analytical reagents (copper). Sunscreen agents can also be prepared.
low toxicity. Rat oral LD50 6000mg/kg. lookg lined with plastic bags, external iron drum packaging. Store in a cool, dry, ventilated warehouse. To prevent heat, moisture, avoid sun exposure. Light loading and light unloading during handling to prevent package breakage. According to the general provisions of the storage and transportation of chemicals.
pH indicator color change ph range | 3.5 |
LogP | 0.96 at 25℃ |
(IARC) carcinogen classification | 3 (Vol. 16, Sup 7) 1987 |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
overview | 4-aminobenzoic acid is one of the most important aromatic amino acids and an important part of substances necessary for the growth and division of body cells. it plays an irreplaceable role in the metabolism of life and has a high content in yeast, liver, bran and malt. 4-Aminobenzoic acid can relieve anemia caused by red blood cell deficiency, viral anemia, inflammatory diarrhea and anemia during pregnancy. 4-aminobenzoic acid as the main ingredient of high-efficiency nutrition-multivitamin B- 100, can effectively improve the body's three major metabolism, comprehensively fight fatigue and relieve stress. The compatibility of 4-aminobenzoic acid and penicillin or streptomycin can effectively improve the antibacterial effect. |
Application | 4-aminobenzoic acid is also an important fine chemical raw material. In medicine, it is a synthetic blood tonic-folic acid, procoagulant-p-carboxybenzylamine The key intermediate is also used to make drugs for the treatment of rickets, rheumatism, arthritis, and tuberculosis. In the cosmetics industry, it is an important intermediate for human sunscreen and hair growth agent; in the organic chemical industry, it is used to prepare various ester products, which can be used as resin modifiers, and can also be used to synthesize reactive dyes, special intermediates of azo dyes. |
the preparation method of | 4-aminobenzoic acid is as follows: 38.0g of p-nitrobenzoic acid, 200mL of water, 20mL of tetrahydrofuran, 0.4g of sodium dodecyl sulfonate and 1.9g of raney nickel are added to the autoclave, replaced three times of nitrogen, filled with hydrogen, adjusted the pressure to 0.9±0.1MPa, adjusted the temperature to 100±2 ℃, and the heat preservation and pressure maintaining reaction is 4 hours to complete. After the reaction is over, the catalyst is filtered and recovered, the catalyst is separated by standing, the water layer is directly applied, the tetrahydrofuran layer is distilled and recovered, and then 1.5g of activated carbon is added to the mother liquor of 4-aminobenzoic acid, heated and refluxed under the protection of nitrogen for 20min, filtered, the mother liquor is cooled and crystallized, filtered, and dried at 80~85 ℃ under vacuum to obtain 30.3g of 4-aminobenzoic acid with a yield of 97.2% and a melting point of 187.1~187.6 ℃, the content is 100.2% (permanent titration). |
Use | Used as an intermediate in medicine and dye Dyes and pharmaceutical intermediates. It is used for the production of reactive red M-80,M-10B, reactive red purple X-2R and other dyes and the production of cyanobenzoic acid to produce drug p-carboxybenzylamine. p-aminobenzoic acid can be used as a sunscreen, and its derivative p-dimethylcarbamate is an excellent sunscreen. the trade name Padimate o. Widely distributed in nature as a B complex factor. Baker holmium east contains 5 to 6 ppm, brewer holmium east from 10 to 100 ppm. Occurs free and in ester form. used as a reagent for the determination of copper. Used for the synthesis of esters, folic acid and azo dyes. Used as an analytical reagent, sunscreen, and also used in the pharmaceutical and dye industries |
production method | add water, sodium chloride and hydrochloric acid in sequence into the reaction pot. Stir and raise the temperature to 50-60 ℃, add 9/10 amount of iron powder, continue to raise the temperature to 98-102 ℃, keep the temperature for 1h, stop heating, slowly add p-nitrobenzoic acid at 95 ℃, add about 1-1.5h, add iron powder, keep the temperature at 98-102 ℃ for 1h, cool to 80 ℃, add 30% liquid alkali to adjust pH = 8.5-9, press filtration, wash with a small amount of water, and combine the filtrate with a small amount of lotion, press into the acid analysis pot, cool to 30-34 ℃, add sodium sulfite to decolorise, and filter. Add acid to adjust pH = 3.5-4, continue to cool to below 10 ℃, throw water and dry to obtain finished product. Yield 84-88%. (2) The industrial product p-nitrobenzoic acid and water are added to a 1000ml beaker obtained by catalytic hydrogenation of p-nitrobenzoic acid, the pH = 6-7 is adjusted with 22% sodium hydroxide under stirring, and then Ruan Ni is added. The feed liquid is pumped into a swing autoclave under stirring, replaced twice with hydrogen and nitrogen respectively, then charged to 3.43MPa, and reacted at a pressure of 3.43-2.54MPa and a temperature of 134-140 ℃ for about 5 hours, until the hydrogen pressure does not drop to the end point. After the reaction, filter and dry to obtain the finished product. The yield is over 80%. |
category | toxic substances |
toxicity classification | poisoning |
acute toxicity | oral administration-mouse LD50: 2850 mg/kg; Oral administration-rabbit LD50: 1000 mg/kg |
flammability hazard characteristics | combustible; combustion produces toxic nitrogen oxide smoke |
storage and transportation characteristics | warehouse ventilation and low temperature drying |
fire extinguishing agent | dry powder, foam, sand, carbon dioxide, mist water |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |