Reaktion #364944

Reaktionsgleichung

bromide

anthranilonitrile

citric acid

1-Bromo-3,4-difluorobenzene

diethyl carbonate

magnesium

→

title compound

4-(3,4-Difluorophenyl)-quinazolin-2-one

Lösungsmittel

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigehad stabilized at 50° C.
2. 2
   workup.ADDITIONAfter complete addition
3. 3
   workup.STIRRINGAfter stirring or two hours at 65° C.
4. 4
   workup.STIRRINGThis solution was stirred for an additional 30 minutes at 65° C.
5. 5
   Temperaturcooled to room temperature
6. 6
   ExtraktionThe mixture was extracted three times with CHCl3 (50 mL)
7. 7
   Waschenthe combined extracts were washed with a 10% Na2CO3 solution
8. 8
   TrocknenThe organics were dried over Na2SO4
9. 9
   Einengenconcentrated
10. 10
    Sonstigetriturated with Et2O

Vorschrift

An oven dried round-bottom flask was charged with magnesium turnings (3.55 g, 146 mmol) in THF (100 mL) under argon. 1-Bromo-3,4-difluorobenzene (4.0 mL, 35.3 mmol) was added to the suspension in one portion. The solution was heated to 40° C. Once the temperature had stabilized at 50° C., the remainder of the bromide (13.52 mL, 155 mmol total) was added dropwise. After complete addition, the solution was stirred for 1 hour at 65° C. A solution of anthranilonitrile (4.95 g, 41.9 mmol) in THF (25 mL) was added dropwise while keeping the internal temperature constant. After stirring or two hours at 65° C., diethyl carbonate (16.3 mL, 135 mmol) was added dropwise to the brownish-red solution . This solution was stirred for an additional 30 minutes at 65° C. and then cooled to room temperature. The solution was poured into a mixture of 250 mL of 1 M citric acid and ice. The mixture was extracted three times with CHCl3 (50 mL) and the combined extracts were washed with a 10% Na2CO3 solution. The organics were dried over Na2SO4, concentrated, and triturated with Et2O to afford the title compound.

Quelle