2,6-Lutidine → (S)-2-(Trifluoromethylsulfonyloxy)propionic acid tert-butyl ester

Temperature

0 °C

In a 500 ml round-bottomed flask, 3.00 g of tert-butyl L-lactate (ee>99%) was dissolved in 165 ml of absolute dichloromethane and cooled to 0° C. under argon. Thereafter, first 3.10 ml of 2.6-lutidine and then slowly 4.15 ml of trifluoromethanesulphonic anhydride were added in succession and the reaction was stirred for 50 min at 0° C. Thereafter, the reaction mixture was diluted with 400 ml of petroleum ether, washed 4 times with 250 ml of a 3:1 mixture of saturated aqueous sodium chloride solution and 1 N hydrochloric acid, dried over MgSO4 and concentrated in vacuo. The residue was applied to a silica gel filter and washed off said filter with a 1:1 mixture of petroleum ether and dichloromethane. After removal of the solvent, the pure tert-butyl (S)-2-trifluoromethanesulphonyloxypropionate (ee>99%) was obtained in a yield of 90%.

1. washwashed 4 times
2. additionwith 250 ml of a 3:1 mixture of saturated aqueous sodium chloride solution and 1 N hydrochloric acid
3. dry with materialdried over MgSO4
4. concentrationconcentrated in vacuo
5. filtrationfilter
6. washwashed off
7. filtrationsaid filter with a 1:1 mixture of petroleum ether and dichloromethane
8. customAfter removal of the solvent

ORD record

ord-62f45721b50c4106890fa070058b87f4

Source dataset

uspto-grants-2012_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08212065B2