Dinitrobenzenes are nitrobenzenes composed of a benzene ring and two nitro group (-NO2) substituents. The three possible arrangements of the nitro groups afford three isomers, 1,2-dinitrobenzene, 1,3-dinitrobenzene, and 1,4-dinitrobenzene. Each isomer has the chemical formula C6H4N2O4 and a molar mass of about 168.11 g/mol. 1,3-Dinitrobenzene is the most common isomer. It is used as a precursor to 1,3-diaminobenzene and 3-nitroaniline.
Properties The dinitrobenzenes are all crystalline solids. The boiling points of the three isomers are relatively close; however, the melting points significantly differ. 1,4-Dinitrobenzene, which has the highest symmetry, has the highest melting point.
+ Dinitrobenzenes IUPAC name 1,2-Dinitrobenzene 1,3-Dinitrobenzene 1,4-Dinitrobenzene Other names o-Dinitrobenzene m-Dinitrobenzene p-Dinitrobenzene Chemical structure CAS number 528-29-0 99-65-0 100-25-4 25154-54-5 (Unspecified isomers) PubChem Chemical formula C6H4N2O4 Molar mass 168.11 g/molMagnetic Susceptibility -65.98·10−6 cm3/mol -70.53·10−6 cm3/mol -68.30·10−6 cm3/mol Physical state solid Appearance white solid yellowish solid pale yellow solid Melting point 118 °C 89.6 °C 174 °C Boiling point 318 °C 297 °C 299 °CBrockhaus ABC Chemie, VEB F.A. Brockhaus Verlag, Leipzig 1971. Density 1.565 g/cm3 (17 °C) 1.575 g/cm3 (18 °C) 1.625 g/cm3 (18 °C) Vapor pressure 0.08 Pa (30 °C)) 0.07 Pa (30 °C) 0.34 Pa (50 °C) 0.23 Pa (50 °C) Solubility Insoluble in water GHS hazards H phrases P phrases
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