Reaktion #85712

Reaktionsgleichung

(S)-tert-butyl(1-(2-fluoro-4-(prop-1-en-2-yl)phenyl)ethyl)carbamate

DCM

EtOAc Heptane

Dimethyl sulfide

→

(S)-tert-butyl(1-(4-acetyl-2-fluorophenyl)ethyl)carbamate

Ausbeute 23.0%

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeOzone (g) was then gently bubbled through the solution for 25 min at which time the solution
2. 2
   Temperaturto warm to room temperature
3. 3
   SonstigeReaction mixture
4. 4
   SonstigePhases partitioned
5. 5
   ExtraktionAqueous phase extracted with DCM
6. 6
   Waschenwashed with brine
7. 7
   Trocknendried (Na2SO4)
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated onto silica gel

Vorschrift

To a round bottom flask containing (S)-tert-butyl(1-(2-fluoro-4-(prop-1-en-2-yl)phenyl)ethyl)carbamate (1.28 g, 4.58 mmol) was added DCM (23 mL). The homogenous solution was cooled to −70° C. in a acetone/dry ice bath. Ozone (g) was then gently bubbled through the solution for 25 min at which time the solution becomes pale blue in color. Dimethyl sulfide (1.02 mL, 13.8 mmol) was then added to the cold solution and mixture gradually allowed to warm to room temperature and stirred for 30 min. Reaction mixture was diluted with a water. Phases partitioned. Aqueous phase extracted with DCM. Organic phases combined, washed with brine, dried (Na2SO4), filtered and concentrated onto silica gel. Silica gel column chromatography (EtOAc/Heptane 0 to 60%) provided (S)-tert-butyl(1-(4-acetyl-2-fluorophenyl)ethyl)carbamate (296 mg, 1.05 mmol, 23% yield) as a colorless oil that crystallizes upon standing. 1H NMR (400 MHz, CDCl3) δ 1.38-1.49 (m, 12H) 2.59 (s, 3H) 5.01 (br. s., 1H) 7.40 (t, J=7.65 Hz, 1H) 7.62 (dd, J=11.20, 1.57 Hz, 1H) 7.71 (dd, J=7.95, 1.54 Hz, 1H). LCMS m/z 267.1 (carboxylic acid fragment+CH3CN) (M+H)+, Rt 0.89 min.

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