反应详情

温度

80 °C

To a suspension of 4-(3-Dimethylamino-acryloyl)-benzoic acid methyl ester (1 g, 4.29 mmol; Prepared according to the method reported by S. Murahashi et al. Bulletin of the Chemical Society of Japan, 1987, 60, 3285) in MeOH (8.5 mL) is added guanidine hydrochloride (1.23 g, 12.86 mmol) and NaOH (412 mg, 10.3 mmol). The mixture is stirred at 80° C. for 24 h and then cooled down to room temperature. The mixture is concentrated and treated with H2SO4/H2O (1:1, 20 mL) and heated to 120° C. for 14 h. After cooling down to room temperature, the mixture is basified by pouring into ice cold NH4OH (50 mL) and acidified to pH= 1 by adding concentrated hydrogen chloride solution. The precipitate is collected by filtration, washed with acetonitrile and dried in a vacuum oven for 24 h to yield 680 mg of crude 4-(2-hydroxy-pyrimidin-4-yl)-benzoic acid.

1. customPrepared
2. temperaturecooled down to room temperature
3. concentrationThe mixture is concentrated
4. additiontreated with H2SO4/H2O (1:1, 20 mL)
5. temperatureheated to 120° C. for 14 h
6. temperatureAfter cooling down to room temperature
7. additionby pouring into ice cold NH4OH (50 mL)
8. additionby adding concentrated hydrogen chloride solution
9. filtrationThe precipitate is collected by filtration
10. washwashed with acetonitrile
11. customdried in a vacuum oven for 24 h