反应详情

温度

0 °C

To a solution of lithium aluminium hydride (0.96 g, 0.025 mol) in tetrahydrofuran (100 mL) was added dropwise at room temperature a solution of ethyl 4-amino-5-chloro-2-methoxybenzoate (intermediate 37; 4.4 g, 0.019 mol) in tetrahydrofuran (25 mL). Then the mixture was refluxed for 2 hours. The excess of hydride was destroyed by successive addition of 1 ml of water, 1 ml of 4N NaOH solution and 2 ml of water, filtered through celite and washed with ethyl acetate. The organic solvent was reduced and hexane was added. The mixture was cooled at 0° C. during 1 hour and then the precipitate was filtrated and washed with hexane. The title compound was obtained as a pale yellow solid (80%) which was used in the next step without further purification.

1. temperatureThen the mixture was refluxed for 2 hours
2. customThe excess of hydride was destroyed by successive addition of 1 ml of water, 1 ml of 4N NaOH solution and 2 ml of water
3. filtrationfiltered through celite
4. washwashed with ethyl acetate
5. additionhexane was added
6. filtrationthe precipitate was filtrated
7. washwashed with hexane