(2S)-2-Amino-4,4-dimethylpentanoic acid → 2-Hydroxy-4,4-dimethylpentanoic acid

Temperature

0 °C

805 mg (5.54 mmol) of 4-methylleucine (racemate) were initially charged in 11 ml of sulphuric acid (1M) and cooled to 0° C. 2.30 g (33.3 mmol) of sodium nitrite as a solution in 6.5 ml of water were then slowly added dropwise over a period of 90 min. The solution was stirred at RT for another 24 h. The mixture was carefully diluted with 10 ml of water and the aqueous phase was extracted five times with 10 ml of methyl tert-butyl ether. The combined organic phases were washed with 25 ml of saturated aqueous sodium chloride solution, dried over sodium sulphate and filtered, and the solvent was removed under reduced pressure. The crude product was used for the next step without further purification. Yield: 667 mg (82% of theory)

1. extractionthe aqueous phase was extracted five times with 10 ml of methyl tert-butyl ether
2. washThe combined organic phases were washed with 25 ml of saturated aqueous sodium chloride solution
3. dry with materialdried over sodium sulphate
4. filtrationfiltered
5. customthe solvent was removed under reduced pressure
6. customThe crude product was used for the next step without further purification

ORD record

ord-d72472775a0a461a8daa0768d46eef91

Source dataset

uspto-grants-2016_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09434690B2