Reaktion #48110

Reaktionsgleichung

sodium hydroxide

potassium tert butoxide

ethyl (4-methoxy-phenyl)-acetate

1-bromo-4-cyano-3-fluoro-benzene

→

1-Bromo-4-cyano-3-(4-methoxy-benzyl)-benzene

Lösungsmittel

methanol

N-methyl-pyrrolidin-2-one

N-methyl-pyrrolidin-2-one

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe mixture is stirred overnight at room temperature
2. 2
   SonstigeThe methanol fraction is evaporated
3. 3
   Extraktionextracted with tert butyl-methyl ether
4. 4
   Extraktionextracted with ethyl acetate several times
5. 5
   SonstigeThe combined ethyl acetate extracts are evaporated
6. 6
   Temperaturthe residue together with 120 mL of N,N-dimethyl formamide and 24.9 g of potassium carbonate heated at 100° C. for 1 hour
7. 7
   workup.ADDITIONThe reaction mixture is diluted with aqueous sodium bicarbonate
8. 8
   Extraktionextracted several times with ethyl acetate
9. 9
   SonstigeThe combined extracts are evaporated
10. 10
    Sonstigethe residue crystallized from methanol

Vorschrift

A mixture of 25 g of ethyl (4-methoxy-phenyl)-acetate, 27.4 g of 1-bromo-4-cyano-3-fluoro-benzene and 20 mL of N-methyl-pyrrolidin-2-one is slowly added to 31.4 g of potassium tert butoxide in 130 mL of N-methyl-pyrrolidin-2-one keeping the temperature below 10° C. After stirring for 1 hour at room temperature, 100 mL of methanol and 137 mL of 1 M aqueous sodium hydroxide are added and the mixture is stirred overnight at room temperature. The methanol fraction is evaporated, the residue is basified with 1 M aqueous sodium hydroxide and extracted with tert butyl-methyl ether. The aqueous phase is acidified with 4 M hydrochloric acid and extracted with ethyl acetate several times. The combined ethyl acetate extracts are evaporated and the residue together with 120 mL of N,N-dimethyl formamide and 24.9 g of potassium carbonate heated at 100° C. for 1 hour. The reaction mixture is diluted with aqueous sodium bicarbonate and extracted several times with ethyl acetate. The combined extracts are evaporated and the residue crystallized from methanol.

Quelle