Reaktion #512239

Reaktionsgleichung

5-bromo-2-chlorobenzoic acid

oxalyl chloride

aluminum trichloride

phenethyl acetate

→

4-(5-bromo-2-chlorobenzoyl)phenethyl acetate

Ausbeute 26.0%

Lösungsmittel

DCM

DMF

DCM

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas cooled in an ice-bath
2. 2
   workup.STIRRINGThe mixture was stirred at room temperature for 4 h
3. 3
   Sonstigethe organic layer was isolated
4. 4
   ExtraktionThe aqueous solution was extracted with 25 mL DCM
5. 5
   WaschenThe combined organic solution was washed with brine (25 mL)
6. 6
   Trocknendried (Na2SO4)
7. 7
   Filtrationfiltered
8. 8
   Sonstigeevaporated
9. 9
   SonstigePurification on silica gel using an ISCO column with 5:1 hexane
10. 10
    SonstigeEtOAc gave intermediate BF (2.1 g, yield 26%)

Vorschrift

To a solution of commercially available 5-bromo-2-chlorobenzoic acid (5 g, 21.23 mmol) in 30 mL of anhydrous DCM was added a catalytic amount of DMF followed by oxalyl chloride (1.95 mL, 22.3 mmol) and stirred for 2 h at room temperature. A mixture of aluminum trichloride (3.68 g, 27.6 mmol) and phenethyl acetate (3.38 mL, 21.23 mmol) in 15 mL DCM was cooled in an ice-bath and the acid chloride was transferred to it using a canula. The mixture was stirred at room temperature for 4 h. The mixture was poured into 100 mL of ice-cold water and the organic layer was isolated. The aqueous solution was extracted with 25 mL DCM. The combined organic solution was washed with brine (25 mL) and dried (Na2SO4), filtered and evaporated. Purification on silica gel using an ISCO column with 5:1 hexane:EtOAc followed by 10:1 hexane:EtOAc gave intermediate BF (2.1 g, yield 26%). 1H NMR (300 MHz, CDCl3): δ 8.12 (d, J=2.4 Hz, 1H), 7.71 (d, J=8.4 Hz, 1H), 7.59 (d, J=2.7 Hz, 1H), 7.56 (d, J=8.4 Hz, 1H), 7.36 (s, 1H), 7.33 (d, J=8.4 Hz, 1H), 7.30 (d, J=8.4 Hz, 1H), 4.31 (t, J=6.9, 6.6 Hz, 2H), 3.01 (t, J=6.9, 6.6 Hz, 2H), 2.04 (s, 3H).

Quelle