Triphenylphosphine → Methyl 3(S)-(acetylthio)butanoate

Temperatur

-23 °C

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).

1. customwas obtained
2. temperatureto slowly warm to 25° C.
3. stirringwas stirred 16 h at 25° C
4. customMost of the THF was removed in vacuo and EtOAc (10 mL) and hexanes (100 mL)
5. additionwere added
6. customInsolubles were removed by filtration
7. customthe residue was purified by chromatography on silica gel

ORD-Eintrag

ord-48412e81f973400d93c728694e5f5413

Quelldatensatz

uspto-grants-1995_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05428033