Reaktion #432699

Reaktionsgleichung

3-bromo-1-propene

magnesium

cyclopropyl (4-fluorophenyl)methanone

ammonium chloride

2-propanone CO2

→

α-cyclopropyl-4-fluoro-α-(2-propenyl)benzenemethanol

Ausbeute 62.0%

Lösungsmittel

1,1'-oxybisethane

1,1'-oxybisethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigepreviously prepared
2. 2
   workup.ADDITIONwas added dropwise, during a 1 hour-period
3. 3
   Sonstigeat a temperature below -5° C
4. 4
   Sonstigeto reach room temperature
5. 5
   workup.STIRRINGstirring
6. 6
   SonstigeThe 1,1'-oxybisethane was decanted
7. 7
   SonstigeThe latter was decanted
8. 8
   Waschenthe combined 1,1'-oxybisethane-phases were washed with 500 parts of water
9. 9
   SonstigeThe organic phase was dried
10. 10
    Filtrationfiltered
11. 11
    Sonstigeevaporated
12. 12
    workup.DISTILLATIONFrom the residue, the forerun was distilled off by "

Vorschrift

To a stirred and cooled (2-propanone/CO2 -bath)Grignard complex previously prepared starting from 254.1 parts of 3-bromo-1-propene, 54.7 parts of magnesium and 1540 parts of anhydrous 1,1'-oxybisethane was added dropwise, during a 1 hour-period, a solution of 330 parts of cyclopropyl (4-fluorophenyl)methanone in 280 parts of anhydrous 1,1'-oxybisethane at a temperature below -5° C. The reaction mixture was allowed to reach room temperature and stirring was continued overnight at room temperature. The mixture was cooled to 0° C. and decomposed with 350 parts of a saturated ammonium chloride solution. The 1,1'-oxybisethane was decanted and the residual salts were suspended twice in 140 parts of 1,1'-oxybisethane. The latter was decanted and the combined 1,1'-oxybisethane-phases were washed with 500 parts of water. The organic phase was dried, filtered and evaporated. From the residue, the forerun was distilled off by "Spinning Band". The distillation residue yielded 255.7 parts (62 %) of α-cyclopropyl-4-fluoro-α-(2-propenyl)benzenemethanol (intermediate 1).

Quelle