Reaktion #85458

Reaktionsgleichung

2,2-difluoro-1,3-benzodioxole-5-carboxylic acid

Vitride

NaOH

→

(2,2-difluoro-1,3-benzodioxol-5-yl)-methanol

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONAt the end of addition the temperature
2. 2
   Temperaturis increased to 40° C. for 2 h
3. 3
   Temperaturmaintaining the temperature at 40-50° C
4. 4
   Sonstigeto separate at 40° C
5. 5
   TemperaturThe organic phase is cooled to 20° C.
6. 6
   Waschenthen washed with water (2×1.5 vol)
7. 7
   Trocknendried (Na2SO4)
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated

Vorschrift

Commercially available 2,2-difluoro-1,3-benzodioxole-5-carboxylic acid (1.0 eq) is slurried in toluene (10 vol). Vitride® (2 eq) is added via addition funnel at a rate to maintain the temperature at 15-25° C. At the end of addition the temperature is increased to 40° C. for 2 h then 10% (w/w) aq. NaOH (4.0 eq) is carefully added via addition funnel maintaining the temperature at 40-50° C. After stirring for an additional 30 minutes, the layers are allowed to separate at 40° C. The organic phase is cooled to 20° C. then washed with water (2×1.5 vol), dried (Na2SO4), filtered, and concentrated to afford crude (2,2-difluoro-1,3-benzodioxol-5-yl)-methanol that is used directly in the next step.

Quelle