p-Toluenesulfonic acid → HCID 15078438, compound

HRID 981969Notes

Reaction equation

HRID 981969 reaction equation
[C:1]1([CH2:7][N:8]2[CH2:13][CH2:12][C:11](OC)([O:14]C)[CH:10]([O:18][CH3:19])[CH2:9]2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C1(C)C=CC(S(O)(=O)=O)=CC=1>CC(C)=O>[C:1]1([CH2:7][N:8]2[CH2:13][CH2:12][C:11](=[O:14])[CH:10]([O:18][CH3:19])[CH2:9]2)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

4

Reactant 2

HCID 6101p-Toluenesulfonic acidHCID 15096756HCID 15096756, compound

Product 1

HCID 15078438HCID 15078438, compoundYield 90.6%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

1-phenylmethyl-3-methoxy-4,4-dimethoxypiperidine (4b, 2.22g, 8.36 mmol) from Example 2 and p-toluenesulfonic acid (3.15 g, 16.6 mmol) was heated to reflux in acetone (100ml) for three hours. After being cooled, the reaction solution was concentrated under vacuum, then slurried in 40ml of 10% sodium hydroxide solution. The aqueous mixture was extracted with 2×60 ml of ether, the combined organic layers were dried over magnesium sulfate, then concentrated under vacuum. The crude residue was purified by chromatography (silica gel; ethyl acetate/hexane; 1:1) to provide the intermediate 1-phenylmethyl-3-methoxy-4-piperidone (5b, 1.66 g, 90%).

Workup

  1. temperatureAfter being cooled
  2. concentrationthe reaction solution was concentrated under vacuum
  3. extractionThe aqueous mixture was extracted with 2×60 ml of ether
  4. dry with materialthe combined organic layers were dried over magnesium sulfate
  5. concentrationconcentrated under vacuum
  6. customThe crude residue was purified by chromatography (silica gel; ethyl acetate/hexane; 1:1)

Sources & evidence

ORD record
ord-2bb149b5b22844639c078df81700a640
Source dataset
uspto-grants-1991_02
Patent number
US04994471

Reaction notes

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