Chemical Properties
light yellow crystalline powder
Uses
4-Nitrobenzoic Acid is used in the synthesis of anti-Trypanosoma cruzi agents in the treatment of chagas disease.
Definition
ChEBI: A nitrobenzoic acid having the nitro group at the 4-position.
Production Methods
p-Nitrobenzoic acid is produced commercially by the oxidation of 4-nitrotoluene with molecular oxygen. Oxidation with 15 % nitric acid at 175 ℃ produces the acid in 88.5 % yield. An interesting method involves the nitration and subsequent oxidation of polystyrene. This method uses the steric hindrance of the polymer chain to improve the para to ortho ratio of the product.
General Description
Odorless pale yellow crystals.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
p-Nitrobenzoic acid is incompatible with strong oxidizers. p-Nitrobenzoic acid is also incompatible with strong bases (potassium hydroxide). p-Nitrobenzoic acid may react with cyanides.
Fire Hazard
p-Nitrobenzoic acid is combustible.
Toxicology
Among various nitroaromatics, 4-nitrobenzoic acid (4-NBA) is one of the simplest and basic derivates of the explosives. Moreover, 4-NBA harms human health and causes severe water and atmosphere pollution. 4-Nitrobenzoic acid is stable, toxic, and non-biodegradable. US/Zn0 was found to degrade more than 85% of 4-nitrobenzoic acid in 30 min. There was an apparent synergistic effect between ultrasound and Zn[1-2].
Purification Methods
Purify it as for 3-nitrobenzoic acid above. The amide has m 201.6o (from H2O). [Beilstein 9 III 1537, 9 IV 1072.]
References
[1] Shan Chong. “Ultrasound/Zn0 for aqueous 4-nitrobenzoic acid degradation.” Desalination and Water Treatment 322 1 (2016): 24990–24998.
[2] Xue-Huan Xin . “A luminescent barium-based metal-organic framework: Synthesis, structure and efficient detection of 4-nitrobenzoic acid.” Inorganic Chemistry Communications 97 (2018): Pages 129-133.