(3,4-Dimethoxyphenyl)acetic acid → 3,4-Dimethoxy-2-phenylacetophenone

HRID 893317Notes

Reaction equation

HRID 893317 reaction equation
[C:1](Cl)(=O)[C:2](Cl)=O.[CH3:7][O:8][C:9]1[CH:10]=[C:11]([CH2:17][C:18]([OH:20])=O)[CH:12]=[CH:13][C:14]=1[O:15][CH3:16]>C1C=CC=CC=1>[CH3:7][O:8][C:9]1[CH:10]=[C:11]([CH2:17][C:18]([C:2]2[CH:1]=[CH:13][CH:14]=[CH:9][CH:10]=2)=[O:20])[CH:12]=[CH:13][C:14]=1[O:15][CH3:16]

Participants

4

Reactant 2

HCID 7139(3,4-Dimethoxyphenyl)acetic acidHCID 65578Oxalyl chloride

Product 1

HCID 123366833,4-Dimethoxy-2-phenylacetophenoneYield 64.8%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

Combine 3.9 g of oxalyl chloride, 2.0 g of 3,4-dimethoxyphenylacetic acid and 50 mL of benzene and stir the mixture at 60° C. for 2.5 h. Remove the excess oxalyl chloride by distillation and concentrate the solution to a volume of 20 mL. Cool the solution to room temperature and add slowly to a suspension of anhydrous aluminium chloride (1.6 g) in 300 mL of benzene over 12 h. Stir the reaction mixture for 6 h., pour into a mixture of ice and conc. hydrochloric acid, then extract with ethyl acetate. Dry the organic extract over Na2SO4, filter and concentrate the filtrate to a residue. Chromatograph the residue on silica gel using 3:7 ethyl acetate/hexane to give 847 mg of α-(3,4-dimethoxyphenyl)-acetophenone. 1H NMR (CDCl3): δ8.1-7.98 (2H, m); 7.62-7.4 (3H, m); 6.76-6.9 (3H, m); 4.24 (2H, s); 3.85 (6H, s).

Workup

  1. customRemove the excess oxalyl chloride
  2. distillationby distillation
  3. concentrationconcentrate the solution to a volume of 20 mL
  4. additionadd slowly to a suspension of anhydrous aluminium chloride (1.6 g) in 300 mL of benzene over 12 h
  5. additionpour into a mixture of ice and conc. hydrochloric acid
  6. extractionextract with ethyl acetate
  7. customDry the
  8. extractionorganic extract over Na2SO4
  9. filtrationfilter
  10. concentrationconcentrate the filtrate to a residue

Sources & evidence

ORD record
ord-5038d819fd144824a0f40d443c36c65e
Source dataset
uspto-grants-1992_06
Patent number
US05124337

Reaction notes

Loading…