Bromocyclopentane → 3-Cyclopentyloxy-4-methoxybenzaldehyde

HRID 1377530Notes

Reaction equation

HRID 1377530 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH:7]=[CH:8][C:9]=1[O:10][CH3:11])[CH:5]=[O:6].C(=O)([O-])[O-].[K+].[K+].Br[CH:19]1[CH2:23][CH2:22][CH2:21][CH2:20]1>CN(C)C=O>[CH:19]1([O:1][C:2]2[CH:3]=[C:4]([CH:7]=[CH:8][C:9]=2[O:10][CH3:11])[CH:5]=[O:6])[CH2:23][CH2:22][CH2:21][CH2:20]1

Participants

5

Reactant 3

HCID 8728Bromocyclopentane2×HCID 11430Potassium CarbonateHCID 12127Isovanillin

Product 1

HCID 27358933-Cyclopentyloxy-4-methoxybenzaldehydeYield 90.8%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
100 °C

Procedure

A mixture of 3-hydroxy-4-methoxybenzaldehyde (40 g, 0.26 mol), potassium carbonate (40 g, 0.29 mol) and bromocyclopentane (32 ml, 0.31 mol) in dimethylformamide (0.25 l) was heated under an argon atmosphere at 100° C. After 4 hours, additional bromocyclopentane (8.5 ml, 0.08 mol) was added and heating was continued for 4 hours. The mixture was allowed to cool and was filtered. The filtrate was concentrated under reduced pressure and the residue was partitioned between ether and aqueous sodium bicarbonate. The organic extract was washed with aqueous sodium carbonate and was dried (potassium carbonate). The solvent was removed in-vacuo and the residue was purified by flash chromatography, eluting with 2:1 [may also be distilled at ~0.02 mm Hg] hexanes/ether to provide a pale yellow oil (52 g, 89%).

Workup

  1. temperatureheating
  2. waitwas continued for 4 hours
  3. temperatureto cool
  4. filtrationwas filtered
  5. concentrationThe filtrate was concentrated under reduced pressure
  6. customthe residue was partitioned between ether and aqueous sodium bicarbonate
  7. extractionThe organic extract
  8. washwas washed with aqueous sodium carbonate
  9. dry with materialwas dried (potassium carbonate)
  10. customThe solvent was removed in-vacuo
  11. customthe residue was purified by flash chromatography
  12. washeluting with 2:1 [
  13. distillationmay also be distilled at ~0.02 mm Hg] hexanes/ether

Sources & evidence

ORD record
ord-0d7932def94a41e89423c0c475c334f5
Source dataset
uspto-grants-1997_09
Patent number
US05665737

Reaction notes

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