Method of producing n-alkylaminophenols

Abstract

N-alkyl amino phenols, such as N-ethyl-m-amino phenol are produced in high yield and with high purity by reacting a divalent phenol, such as resorcinol, with an alkylamine, such as ethylamine, in the absence of catalyst and solvent, at a temperature of 120.degree.-210.degree. C. under elevated pressure in an inert gas atmosphere. In a first embodiment, the resulting reaction mixture is acidified to convert the N-alkylaminophenol to its water soluble salt and the resulting aqueous layer is separated from the oily layer. The aqueous layer is rendered alkaline to liberate N-alkylaminophenol as an oily layer. The N-alkyl-aminophenol oily layer is then separated from the aqueous layer and distilled. In an alternative embodiment, the reaction mixture resulting from the reaction between the divalent phenol and alkylamine is combined with an aqueous solution of an alkali to convert unreacted phenol to its water soluble salt while the product N-alkylaminophenol remains in an oily phase which is separated from the aqueous phase. An organic solvent is used as an extractant. The recovered N-alkylaminophenol organic solution is then distilled to recover N-alkylaminophenol. Purities of the recovered N-alkylaminophenol in excess of 95% can be achieved.