4methoxyaniline

4-methoxyaniline, commonly known as p-anisidine, is an organic compound used principally as an intermediate in the synthesis of dyes, pigments, and pharmaceutical compounds. Its molecular formula is C7H9NO2 and its molecular weight is about 139.15 g/mol. The structure features a benzene ring bearing an amino group (NH2) para to a methoxy group (OCH3), giving the para-substituted aniline derivative.

At room temperature it is typically a colorless to pale yellow liquid with a characteristic sharp, amine-like odor. It is soluble in many organic solvents and has limited water solubility. Its physical properties make it convenient for use in organic synthesis and in formulations requiring a stable arylamino ether.

Industrial production routes for 4-methoxyaniline include O-methylation of suitable aminophenol precursors or other methods that introduce the methoxy substituent onto a para-aminated aromatic framework. It serves as a versatile starting material for constructing more complex anisidine derivatives and azo dyes, contributing to applications in textile coloration and related industries, as well as serving as an intermediate in certain pharmaceutical and agrochemical syntheses.

Safety and handling notes are important: 4-methoxyaniline is an irritant to skin, eyes, and the respiratory tract and can be harmful if inhaled or ingested. Prolonged or repeated exposure should be avoided, and handling should occur in a well-ventilated area with appropriate personal protective equipment. It should be stored in a tightly closed container, away from oxidizers and sources of heat. Regulatory controls for aniline derivatives typically apply to occupational exposure and handling practices.