Reaktion #94395

Reaktionsgleichung

3-bromomethylbiphenyl

3-Bromomethylbiphenyl

heptane

3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylic acid

Potassium hydroxide

→

[1,1'-biphenyl]-3-ylmethyl 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate

Ausbeute 54.4%

Lösungsmittel

acetonitrile

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigemay be prepared
2. 2
   workup.ADDITIONwas added
3. 3
   Temperaturthe mixture was heated
4. 4
   Temperaturunder reflux
5. 5
   Sonstigeto remove the water from the mixture
6. 6
   TemperaturThe dry mixture was then cooled to 60°
7. 7
   TemperaturThe mixture was then heated
8. 8
   Temperaturunder reflux for 5.5 hours
9. 9
   Sonstigewere separated
10. 10
    Extraktionbefore being extracted twice with 100 ml portions of heptane
11. 11
    Waschenthe combined organic phase was washed with one 200 ml portion of a saturated sodium chloride solution
12. 12
    SonstigeThe solvent was removed from the organic phase
13. 13
    Sonstigea rotary evaporator
14. 14
    Sonstigeleaving an oily, straw-colored residue
15. 15
    workup.DISTILLATIONThe oil was distilled in a short path, air-bath
16. 16
    Temperaturheated
17. 17
    workup.DISTILLATIONKugelrohr distillation apparatus at a pressure of 0.25 mm
18. 18
    SonstigeAfter removing low boilers from the oil at a temperature below 145°

Vorschrift

Potassium hydroxide (2.0 g, 0.032 mole) was dissolved in 7 ml of water. To this solution was added 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylic acid (6.6 g, 0.032 mole), which may be prepared according to the method of Farkas, et al., loc. cit. After dissolution, 100 ml of heptane was added, and the mixture was heated under reflux using a DeanStarke trap to remove the water from the mixture. The dry mixture was then cooled to 60°, and a solution of 3-bromomethylbiphenyl (7.5 g, 0.032 mole) and 0.1 g of 1,4-diazabicyclo[2.2.2]octane in 60 ml of acetonitrile was added. 3-Bromomethylbiphenyl may be prepared according to the method of M. Gomberg and J. C. Pernert, J. Am. Chem. Soc., 48, 1372 (1926) and H. O. Huisman, et al., Rec. Trav. Chim., 71, 899 (1951). The mixture was then heated under reflux for 5.5 hours. After cooling to room temperature, the reaction mixture was contacted with 100 g of ice in a separatory funnel, and when the ice had melted the phases were separated. The aqueous phase was saturated with sodium chloride before being extracted twice with 100 ml portions of heptane. The heptane extracts and the organic phase were combined, and the combined organic phase was washed with one 200 ml portion of a saturated sodium chloride solution. The solvent was removed from the organic phase using a rotary evaporator, leaving an oily, straw-colored residue weighing 9.9 g. The oil was distilled in a short path, air-bath heated Kugelrohr distillation apparatus at a pressure of 0.25 mm. After removing low boilers from the oil at a temperature below 145°, [1,1'-biphenyl]-3-ylmethyl 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate (6.5 g, 54.4% yield) was obtained at a temperature of 165°-175°.

Quelle