Triethylsilane → (S)-2-amino-4,4-difluoro-pentanoic acid methyl ester

Temperature

25 °C

In a flask under argon was placed (S)-2-benzyloxycarbonylamino-4,4-difluoro-pentanoic acid methyl ester (626 mg, 2.08 mmol), methanol (8 mL) and 10% palladium on activated carbon (100 mg). Triethylsilane (3 mL) was added slowly and the mixture stirred at 25° C. for 30 min. Another portion of 10% palladium on activated carbon (100 mg) and triethylsilane (3 mL) was added and the mixture was stirred for 30 min. A third portion of 10% palladium on activated carbon (100 mg) and triethylsilane (3 mL) was added and the mixture was stirred for 30 min. The mixture was filtered to remove the catalyst and the solids washed with methanol. The filterate was concentrated in vacuo, azeotroped with toluene, dissolved in dichloromethane and concentrated in vacuo with silica gel (2 g). Purification by Biotage flash chromatography (Aspire 40 g column, 100% ethyl acetate) afforded (S)-2-amino-4,4-difluoro-pentanoic acid methyl ester (151 mg) as a clear colorless liquid.

1. customIn a flask under argon was placed
2. stirringthe mixture was stirred for 30 min
3. stirringthe mixture was stirred for 30 min
4. filtrationThe mixture was filtered
5. customto remove the catalyst
6. washthe solids washed with methanol
7. concentrationThe filterate was concentrated in vacuo
8. customazeotroped with toluene
9. dissolutiondissolved in dichloromethane
10. concentrationconcentrated in vacuo with silica gel (2 g)
11. customPurification by Biotage flash chromatography (Aspire 40 g column, 100% ethyl acetate)

ORD record

ord-a5f207c3c18646ceb932bfd46a4ee98e

Source dataset

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07741327B2