Reaktion #50704

Reaktionsgleichung

methyl 3(R)-hydroxybutyrate

thiolacetic acid

PPh3

DEAD

→

title compound

Ausbeute 45.0%

Methyl 3(S)-(acetylthio)butanoate

Ausbeute 45.0%

Lösungsmittel

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas obtained
2. 2
   Temperaturto slowly warm to 25° C.
3. 3
   workup.STIRRINGwas stirred 16 h at 25° C
4. 4
   SonstigeMost of the THF was removed in vacuo and EtOAc (10 mL) and hexanes (100 mL)
5. 5
   workup.ADDITIONwere added
6. 6
   SonstigeInsolubles were removed by filtration
7. 7
   Sonstigethe residue was purified by chromatography on silica gel

Vorschrift

To a -23° C. solution of PPh3 (40 mmol, 10.48 g) in THF (100 mL) was added DEAD (diethylazodicarboxylate) (40 mmol, 6.28 mL) dropwise and the mixture was stirred at -23° C. for 16 h, during which time a white precipitate was obtained. A THF (30 mL) solution of methyl 3(R)-hydroxybutyrate (20 mmol, 2.36 g) and thiolacetic acid (40 mmol, 2.85 mL) was slowly added and the mixture was allowed to slowly warm to 25° C. and was stirred 16 h at 25° C. Most of the THF was removed in vacuo and EtOAc (10 mL) and hexanes (100 mL) were added. Insolubles were removed by filtration and the residue was purified by chromatography on silica gel to afford the title compound (yield: 45%). [α]D25 =-21 ° (c=3, CHCl3 ). 1H NMR (acetone d6) δ1.30 (3H, d), 2.25 (3H, s), 2.45-2.80 (2H, m), 3.62 (3H, s), 3.75-3.95 (1H, m).

Quelle