4-Nitrophenol

4-Nitrophenol is a yellowish crystalline substance with moderate toxicity, belonging to the phenolic compound. 4-Nitrophenol has two crystalline forms. The α form is a colorless needle-shaped crystal that is unstable at room temperature but stable under sunlight. The β form is a yellow needle-shaped crystal that is stable at room temperature and gradually turns red under sunlight. 4-Nitrophenol in normal state is a mixture of these two forms. The boiling point of 4-Nitrophenol is 279 degrees Celsius (1013 hPa), the density is 1.48 g/cm3 (20℃), the flash point is 169.0 degrees Celsius, the ignition point is 510 degrees Celsius, and the melting point is 110-114 degrees Celsius.

The preparation method is hydrolytic acidification of p-nitrochlorobenzene to obtain p-nitrophenol. Sodium hydroxide solution with a concentration of 137-140 g/L is added to the hydrolysis kettle, and then molten p-nitrochlorobenzene is added. Heated to 152 ℃, the pressure in the kettle is 0.4 MPa, and then stop heating, the hydrolysis reaction exotherm makes the temperature and pressure naturally rise to 165 ℃, about 0.6 MPa. After holding for 3h, take a sample to check the end of the reaction. After the reaction, the hydrolysate was cooled to 120℃. Add the hydrolysate, a certain amount of concentrated sulfuric acid and water into the crystallization kettle, and cool to about 50 ℃. Add concentrated sulfuric acid to make the Congo red test paper purple, continue to cool to 30 ℃, suction filtration, centrifugal removal of water, that is, the content of more than 90% of p-nitrophenol.

4-Nitrophenol can be prepared by hydrolysis of p-nitrochlorobenzene or p-nitrobromobenzene in a water-DMSO solution of potassium hydroxide. 4-Nitrophenol can be used as a pH indicator, and 4-Nitrophenol is also an intermediate in the production of acetaminophen. In addition, it is used as a precursor for the preparation of phenylethylamine and acetylphenethylamine, as an indicator and as a raw material for fungicides. In peptide synthesis, carboxylate derivatives of 4-Nitrophenol can be used as active components for the construction of amide moieties.

Molecular Weight:139.11
XLogP3:1.9
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Exact Mass:139.026943022
Monoisotopic Mass:139.026943022
Topological Polar Surface Area:66
Heavy Atom Count:10
Complexity:123
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes