PURPOSE: o-Nitrotoluene is reduced with hydrogen in the presence of a noble metal catalyst and dilute sulfuric acid and the reaction is stopped while the organic layer keeps fluidized state, then the organic layer is extracted with a basic aqueous solution to recover a by-product of amine used in dye production and produce the titled compound in high yield.
CONSTITUTION: When o-nitrotoluene is brought into contact with molecular hydrogen in the presence of a noble metal catalyst such as platinum catalyst and dilute sulfuric acid at 50W120°C to produce 4-amino-3-methylphenol, the hydrogenation reaction is stopped while the organic layer keeps sufficient fluidity and the reaction mixture is separated into the dilute sulfuric acid layer and the organic layer. Then, 2,2'-diemthyl-4-hydroxydiphenylamine is extracted from the organic layer with a basic aqueous solution, whereby 2,2'-diemethyl-4-hydroxydiphenylamine is obtained, when 4-amino-3-methylphenol is produced.
NAGATA TERUYUKI
KAJIMOTO NOBUYUKI
WADA MASARU
