PRODUCTION OF ANILINE DERIVATIVE

PURPOSE:To produce an aniline derivative useful as a starting raw material for herbicide in one step and high yield by reacting an aminophenol derivative with an alkylation agent under specific condition without protecting the amino group of the aminophenol derivative. CONSTITUTION:The aniline derivative of formula III (e.g. 2-fluoro-4-chloro-5- cyclopentyloxyaniline) is produced by reacting a halogen-substituted aminophenol of formula I (X and X are halogen) (e.g. 2-chloro-4-fluoro-5-aminophenol) with an alkylation agent of formula II [R is (substituted) cycloalkyl; Y is eliminable group] (e.g. cyclopentyl bromide) in a binary phase system consisting of an aqueous solution of an alkali metal hydroxide and an organic solvent in the presence of a phase-transfer catalyst (especially preferably quaternary ammonium salt) or in an organic solvent in the presence of an alkali metal carbonate.