Reaktion #10396

Reaktionsgleichung

sodium cyanoborohydride

4,5-difluoroanthranilic acid

acetic acid

[(1-ethoxycyclopropyl)oxy]trimethylsilane

→

solid

Ausbeute 94.8%

2-Cyclopropylamino-4,5-difluorobenzoic acid

Ausbeute 94.8%

Lösungsmittel

ethyl acetate

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe reaction mixture is heated to reflux
2. 2
   workup.WAITAfter 16 hours
3. 3
   Filtrationfiltered
4. 4
   Waschenwashed with methanol
5. 5
   Einengenthe combined filtrate concentrated under vacuum
6. 6
   Sonstigeto afford a viscous oil
7. 7
   Waschenwashed with 1.0 M hydrochloric acid, water, and brine
8. 8
   TrocknenThe organic layer is dried over MgSO4
9. 9
   Filtrationfiltered
10. 10
    Einengenthe filtrate is concentrated under vacuum

Vorschrift

To a solution of 4,5-difluoroanthranilic acid (1.13 g, 6.53 mmol) in anhydrous methanol (40 mL) is added molecular sieves (3 Å), acetic acid (3.70 mL, 65.3 mmol) and [(1-ethoxycyclopropyl)oxy]trimethylsilane (5.25 mL, 26.11 mmol). After 30 minutes, sodium cyanoborohydride (2.08 g, 32.64 mmol) is added, and the reaction mixture is heated to reflux. After 16 hours, the reaction is cooled to room temperature, filtered, washed with methanol, and the combined filtrate concentrated under vacuum to afford a viscous oil. The resulting oil is dissolved in ethyl acetate and washed with 1.0 M hydrochloric acid, water, and brine. The organic layer is dried over MgSO4, filtered, and the filtrate is concentrated under vacuum to afford as a beige solid (1.32 g). MS CI: m/z 212 (M+).

Quelle