Acetaldehyde → 2-Methylchromone

HRID 1004779Notes

Reaction equation

HRID 1004779 reaction equation
[OH:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[C:8](=[O:13])[CH2:9]S(C)=O.[CH:14](=O)[CH3:15].N1CCCCC1>C1(C)C=CC=CC=1.C(OCC)(=O)C>[CH3:14][C:15]1[O:1][C:2]2[C:3]([C:8](=[O:13])[CH:9]=1)=[CH:4][CH:5]=[CH:6][CH:7]=2

Participants

6

Reactant 3

HCID 177AcetaldehydeHCID 8082PiperidineHCID 578088HCID 578088, compound

Product 1

HCID 2526902-MethylchromoneYield 86%

Reagents, catalysts & solvents 2

HCID 1140TolueneSolventHCID 8857Ethyl AcetateSolvent

Procedure

In an atmosphere of argon, 19.5 g (107.0 mmols) of 2'-hydroxy-2-(methylsulfinyl)acetophenone, 5.65 g (3.4 equivalent) of acetaldehyde and 5.0 ml (0.05 equivalent) of piperidine were dissolved in 500 ml of toluene, and the mixture obtained was refluxed with heating for 1 hour and 45 minutes. The reaction solution was cooled to room temperature and concentrated under reduced pressure to remove the toluene. The residue thus obtained was dissolved in 300 ml of ethyl acetate and washed twice with 200 ml of water. The organic layer thus formed was dried with anhydrous sodium sulfate, followed by concentration under reduced pressure. The residue thus obtained was purified by silica gel column chromatography (developing system: hexane/ethyl acetate=4/6) to obtain 14.7 g of 2-methylchromone (yield: 86%; a pale-white pink solid). 1H-NMR Spectrum [δ(ppm)]: 2.39(s, 3H), 6.17(s, 1H), 7.37(m, 2H), 7.64(dt, 1H, J=1.7 Hz, 8.1 Hz), 8.18(dd, 1H, J=1.7 Hz, 8.1 Hz)

Workup

  1. customthe mixture obtained
  2. temperaturewas refluxed
  3. temperaturewith heating for 1 hour and 45 minutes
  4. concentrationconcentrated under reduced pressure
  5. customto remove the toluene
  6. customThe residue thus obtained
  7. washwashed twice with 200 ml of water
  8. customThe organic layer thus formed
  9. dry with materialwas dried with anhydrous sodium sulfate
  10. concentrationfollowed by concentration under reduced pressure
  11. customThe residue thus obtained
  12. customwas purified by silica gel column chromatography (developing system: hexane/ethyl acetate=4/6)

Sources & evidence

ORD record
ord-3167ccc862a045f9a5d7b2823a3b7dca
Source dataset
uspto-grants-2000_04
Patent number
US06051722

Reaction notes

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