| 摘要 |
PURPOSE:To prepare the titled compound in high yield, by reacting aniline with acetones in the presence of an acidic catalyst while adding an aliphatic hydrocarbon having an azeotropic boiling point with water of lower than a specific temperature, thereby azeotropically removing the produced water from the reaction system. CONSTITUTION:2,2,4-Trimethyl-1,2-dihydroquinoline useful as an age resistor for polymers, is prepared by reacting aniline with aceton, diacetone alcohol or mesityloxide in the presence of an acidic catalyst such as p-toluenesulfonic acid. In the above reaction, an aliphatic hydrocarbon having an azeotropic boiling point with water of <=80 deg.C, e.g. n-hexane, cyclohexane, n-heptane, isooctane, etc. is added to the reaction system, and the produced water is azeotropically removed from the system during the reaction. The formation of polymers and other by-products can be suppressed and the yield of the objective compound is improved. |
