(2R)-2-Bromopropanoic acid → (S)-2-(Acetylthio)-propanoic Acid

To a light green solution of potassium thioacetate (3.94 g, 34.5 mmol) in acetonitrile (150 ml) was added a solution of (R)-2-bromopropanoic acid (4.8 g, 31 mmol) in acetonitrile (12 ml) at room temperature under an argon atomosphere. The resulting white slurry was stirred at room temperature for 2 hours then filtered. The filtrate was concentrated in vacuo. The,residue was diluted in ethyl acetate (100 ml), washed with a 10% aqueous solution of potassium bisulfate (50 ml) and brine, dried (sodium sulfate), and concentrated in vacuo. The crude product (4.61 g) was purified by flash chromatography (60 g--Merck silica gel, 1:45:54 acetic acid/ethyl acetate/hexane) to afford 3.7 g of the title product as a light yellow oil; [α]D =-114° (c=0.50, methanol).

1. filtrationthen filtered
2. concentrationThe filtrate was concentrated in vacuo
3. additionThe,residue was diluted in ethyl acetate (100 ml)
4. washwashed with a 10% aqueous solution of potassium bisulfate (50 ml) and brine
5. dry with materialdried (sodium sulfate)
6. concentrationconcentrated in vacuo
7. customThe crude product (4.61 g) was purified by flash chromatography (60 g--Merck silica gel, 1:45:54 acetic acid/ethyl acetate/hexane)

ORD record

ord-511ecf457667449cb7f786247bef41ae

Source dataset

uspto-grants-1997_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05627278