Potassium Bromide → (S)-2-bromo-4-methylpentanoic acid

Temperature

-10 °C

Potassium bromide (9.5 g., 80 mmol.) was added to a stirred solution of D-leucine (3.0 g., 23 mmol.) in 2.5N sulfuric acid (47 ml.) at room temperature. The reaction mixture was cooled to -10° C. and solid sodium nitrite (2.4 g., 34 mmol.) was added portionwise, maintaining the temperature between -10° and -5° C. After addition was complete, the reaction was stirred for 1 hour and then warmed to room temperature and stirred for another hour. The reaction mixture was then extracted twice with ether, the ether extracts were washed once with water, dried (magnesium sulfate), filtered and evaporated to give 2.7 g. of crude title product.

1. temperaturemaintaining the temperature between -10° and -5° C
2. additionAfter addition
3. temperaturewarmed to room temperature
4. stirringstirred for another hour
5. extractionThe reaction mixture was then extracted twice with ether
6. washthe ether extracts were washed once with water
7. dry with materialdried (magnesium sulfate)
8. filtrationfiltered
9. customevaporated
10. customto give 2.7 g

ORD record

ord-55b5f556cd574d2388c243a0144f1618

Source dataset

uspto-grants-1998_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05756832