Ortho Nitro Chloro Benzene

Ortho Nitro Chloro Benzene (ONCB), also known as 2-Nitrochlorobenzene, is an aromatic nitro compound with the molecular formula C₆H₄ClNO₂ and CAS No. 88-73-3. It appears as a light yellow crystalline solid or liquid, depending on temperature and purity. ONCB is a key intermediate in the production of dyes, pigments, agrochemicals, and pharmaceuticals. It is synthesized via nitration of chlorobenzene, yielding a mixture of isomers, with ONCB comprising approximately 34–36% of the output. Its dual functional groups—nitro and chloro—make it highly reactive in nucleophilic substitution and reduction reactions, enabling conversion to 2-chloroaniline and other derivatives. ONCB is insoluble in water but soluble in organic solvents like benzene, ether, and hot ethanol. Indian manufacturers supply ONCB in technical and high-purity grades, supporting applications in basic pharma, dye intermediates, and specialty chemicals. It must be handled with care due to its toxic and irritant properties, with strict adherence to safety protocols.