onitroanisole

2‑Nitroanisole, commonly abbreviated onitroanisole, is an organic compound with the formula C7H7NO3. It is a colorless liquid and belongs to the nitroanisole family of aromatic Nitro derivatives. The compound consists of a benzene ring bearing a methoxy group (OCH3) and a nitro group (NO2) in the ortho position relative to each other. Its systematic name is 2‑nitro‑1‑methoxybenzene, and it is sometimes referred to as ortho‑nitroanisole or o‑nitroanisole.

Physical properties of 2‑nitroanisole include a boiling point around 165–168 °C, a density of 0.881 g cm‑3 at 20 °C, and limited solubility in water (≈0.75 g L‑1). It is miscible with common organic solvents such as ethanol, acetone, and dichloromethane. Infrared spectra display characteristic nitro stretching bands near 1520 and 1350 cm‑1, while ^1H NMR shows signals for the aromatic protons around 6.8–7.4 ppm and the methoxy methyl protons at 3.7 ppm.

Atypical synthesis of onitroanisole is usually achieved by controlled nitration of anisole using a mixture of concentrated nitric and sulfuric acids or by oxidative nitration with silver salts, yielding the ortho isomer preferentially due to steric orientation. Purification is typically performed by recrystallization from ethanol.

In organic synthesis, onitroanisole serves as a useful electrophilic aromatic substitution partner and as an intermediate for the preparation of arylamines, dyes, and agrochemicals. Its nitro group can be reduced to an amine or further transformed by coupling reactions. The compound is handled with care, as it is flammable, can form explosive peroxides, and may exhibit acute toxicity upon ingestion or inhalation.

Safety guidelines recommend performing all manipulations in a fume hood, using appropriate personal protective equipment, and storing the material in a cool, dry, well‑ventilated area away from oxidizing agents and strong acids.