反应详情

温度

0 °C

The 2-amino-3-bromo-5-methylbenzoic acid (20.0 g, 86.0 mmol) was dissolved in tetrahydrofuran (200 ml) and cooled to 0° C. A solution of borane dimethylsulfide complex (15.6 mL, 156.0 mmol) was dissolved in tetrahydrofuran (40 mL) and added dropwise. The solution was kept at 0° C. for an additional 30 minutes, warmed to room temperature for 2 h and finally refluxed for 16 h. The solution was cooled to room temperature and methanol (10 mL) added slowly to control the gas evolution. The solution was stirred for 30 minutes at room temperature and 1 N hydrochloric acid added. The solution was stirred for 3 h and solvent removed to a volume of about 100 mL. Water (200 mL) was added and the solution extracted with diethylether (200 mL). The aqueous layer was collected, adjusted to pH=12 with 1N sodium hydroxide which formed a solid in the solution. The solid was collected, dissolved in ethyl acetate (100 mL), dried over sodium sulfate and solvent removed at reduced pressure. The (2-amino-3-bromo-5-methylphenyl)methanol (9.5 g, 43.9 mmol) was obtained as a off white solid. (51% yield): HRMS m/z 216.0047; calcd for M+H 216.0024.

1. additionadded dropwise
2. temperaturewarmed to room temperature for 2 h
3. temperaturefinally refluxed for 16 h
4. temperatureThe solution was cooled to room temperature
5. stirringThe solution was stirred for 3 h
6. customsolvent removed to a volume of about 100 mL
7. additionWater (200 mL) was added
8. extractionthe solution extracted with diethylether (200 mL)
9. customThe aqueous layer was collected
10. customformed a solid in the solution
11. customThe solid was collected
12. dissolutiondissolved in ethyl acetate (100 mL)
13. dry with materialdried over sodium sulfate and solvent
14. customremoved at reduced pressure