| 摘要 |
PURPOSE:To obtain the subject compound free from coloring, useful as an antioxidant by subjecting a (3,5-dialkyl-4-hydroxyphenyl)propionic acid lower alkyl ester to ester exchange in the presence of an alkali metal hydroxide. CONSTITUTION:A 2,6-dialkylphenol and potassium hydroxide are heated to 90 deg.C while stirring, the system is made into a state of reduced pressure and retained for 30 minutes to distill away formed water. Methyl acrylate is dripped to the system under normal pressure at 130 deg.C and reacted for two hours to give a (3,5-dialkyl-4-hydroxyphenyl)propionic acid lower alkyl ester. Then this compound is subjected to transesterification with a higher alcohol such as n- octadecyl alcohol in the presence of an alkaline (earth) metal hydroxide or carbonate to give the objective alkyl-3-(3,5-dialkyl-4-hydroxyphenyl)-propionate. |
