Mononitrobenzene

Mononitrobenzene is an organic compound consisting of a benzene ring with a nitro group (-NO2) attached. It occurs as two different isomers, o-nitrotoluene and p-nitrotoluene, which have similar but distinct chemical and physical properties. The two isomers differ in the position of the nitro group and the methyl group on the benzene ring.

The o-nitrotoluene isomer has the nitro group and methyl group located ortho (next to each other) to each other, while the p-nitrotoluene isomer has them located para (far apart) from each other. Both isomers are industrial chemicals and have significant market presence.

Mononitrobenzene is a colorless or pale yellowish liquid at room temperature, having a pungent and distinctive odor, similar to nitrobenzol. It is readily soluble in organic solvents but poorly soluble in water. Mononitrobenzene is also known under the common names o-nitrotoluene or PNB.

The chemical properties of mononitrobenzene exhibit somewhat unique characteristics, compared to other nitroaromatic compounds. This property influences its application in industrial processes, where its reactivity to various nucleophiles provides a selective advantage. It is also a key intermediate in the manufacture of various pharmaceutical and pesticide chemicals.

Under standard conditions, mononitrobenzene consists of isomers that belong to the Category 1 explosive properties as per the EU's Dangerous Substances Directive. Handling and safety precautions for the substances should be taken as a standard practice.