Ethyl (3R)-2-azido-4,4,4-trifluoro-3-methylbutanoate → Ethyl (3R)-4,4,4-trifluorovalinate

32.8 g of crude ethyl (3R)-2-azido-4,4,4-trifluoro-3-methylbutanoate (diastereomer mixture) were dissolved in 110 ml of ethanol and, after inertizing with argon, 6.98 g of palladium on carbon (5%) were added. The mixture was stirred overnight at standard pressure under an atmosphere of hydrogen, with the reaction vessel repeatedly being vented and filled with fresh hydrogen. The reaction mixture was then filtered off through Celite, the filter residue was washed with 50 ml of ethanol and the filtrate was concentrated under reduced pressure (up to about 20 mmHg). The slightly yellowish liquid that remained was briefly freed from residual solvent under high vacuum. This gave 23.5 g of the target compound as an about 70% pure crude product which was not purified any further (yield over three steps about 38% of theory).

1. additionwere added
2. filtrationThe reaction mixture was then filtered off through Celite
3. washthe filter residue was washed with 50 ml of ethanol
4. concentrationthe filtrate was concentrated under reduced pressure (up to about 20 mmHg)
5. customThis gave 23.5 g of the target compound as an about 70% pure crude product which was not purified
6. customany further (yield over three steps about 38% of theory)

ORD record

ord-d45ecd8194224e82839b9bf3de7bea70

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09309198B2