Hydrochloric Acid → (2-Bromopyridin-4-yl)methanol

17.4 g of sodium borohydride was suspended in 1.6 liters of tetrahydrofuran, and the suspension was stirred by a mechanical stirrer. The suspension was cooled with ice-water, and 62.2 g of 2-bromo-4-pyridinecarboxylic acid was added little by little. The mixture was heated to room temperature, and stirred until evolution of hydrogen ceased. A solution of 75.8 ml of boron trifluoride etherate in 500 ml of tetrahydrofuran was added dropwise at room temperature for 3 hours. After the addition, the mixture was stirred for 20 hours. The reaction solution was cooled with ice-water, and acidified to a pH of 1 to 2 by adding 1.5N hydrochloric acid. Tetrahydrofuran was evaporated under reduced pressure. A 4N aqueous solution of sodium hydroxide was added to adjust the pH of the mixture to 10 to 11. It was extracted with ethyl acetate, and the organic layer was washed with a saturated aqueous solution of sodium chloride. The aqueous layer was further extracted with ethyl acetate twice. The organic layers were combined, and dried over anhydrous sodium sulfate. The dried product was concentrated under reduced pressure to give 51.3 g of 2-bromo-4-pyridinemethanol in a yield of 88%.

1. additionwas added little by little
2. additionAfter the addition
3. stirringthe mixture was stirred for 20 hours
4. customTetrahydrofuran was evaporated under reduced pressure
5. additionA 4N aqueous solution of sodium hydroxide was added
6. extractionIt was extracted with ethyl acetate
7. washthe organic layer was washed with a saturated aqueous solution of sodium chloride
8. extractionThe aqueous layer was further extracted with ethyl acetate twice
9. dry with materialdried over anhydrous sodium sulfate
10. concentrationThe dried product was concentrated under reduced pressure

ORD record

ord-c386aad5aad64658b846aeaab7598d6c

Source dataset

uspto-grants-1990_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04912101