Sodium Hydroxide → 1-[(4-Methoxyphenyl)methyl]-3-methylidenepiperidin-2-one

HRID 894858Notes

Reaction equation

HRID 894858 reaction equation
Cl.[CH3:2][O:3][C:4]1[CH:20]=[CH:19][C:7]([CH2:8][N:9]2[CH2:18][CH2:17][CH2:16][CH:11]([C:12](OC)=O)[CH2:10]2)=[CH:6][CH:5]=1.[OH-:21].[Na+]>CO.O>[CH3:2][O:3][C:4]1[CH:20]=[CH:19][C:7]([CH2:8][N:9]2[CH2:18][CH2:17][CH2:16][C:11](=[CH2:12])[C:10]2=[O:21])=[CH:6][CH:5]=1

Participants

5

Reactant 2

HCID 14798Sodium HydroxideHCID 14181476methyl N-(p-methoxybenzyl)nipecotate hydrochloride

Product 1

HCID 127744231-[(4-Methoxyphenyl)methyl]-3-methylidenepiperidin-2-oneYield 71.4%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

A solution of methyl N-(p-methoxybenzyl)nipecotate hydrochloride (30.7 g) and 8.4 g of sodium hydroxide in 900 ml of methanol and 45 ml of water is stirred at room temperature for seventeen hours. The solution is evaporated to dryness in vacuo, the residue diluted with toluene, and this again evaporated to dryness in vacuo. To the residue is added 1 liter of acetic anhydride and 140 ml of triethylamine, and the resulting mixture is heated under reflux for four hours. The reaction mixture is evaporated to dryness in vacuo, the residue taken up in chloroform, washed with water, dried, and concentrated in vacuo. The residual oil is chromatographed on silica gel using 1:1 hexane-ethyl acetate as the eluant, and yields 16.9 g of 1-(p-methoxybenzyl)-3-methylene-2-piperidone as a chromatographically pure yellow oil. Alternatively, the oil can be distilled to give analytically pure 1-(p-methoxybenzyl)-3-methylene-2-piperidone, b.p. 145°-155°/0.05 mm.

Workup

  1. customThe solution is evaporated to dryness in vacuo
  2. additionthe residue diluted with toluene
  3. customthis again evaporated to dryness in vacuo
  4. additionTo the residue is added 1 liter of acetic anhydride and 140 ml of triethylamine
  5. temperaturethe resulting mixture is heated
  6. temperatureunder reflux for four hours
  7. customThe reaction mixture is evaporated to dryness in vacuo
  8. washwashed with water
  9. customdried
  10. concentrationconcentrated in vacuo
  11. customThe residual oil is chromatographed on silica gel using 1:1 hexane-ethyl acetate as the eluant

Sources & evidence

ORD record
ord-3f58f1c1ea0a4014971ba94220bb9819
Source dataset
uspto-grants-1981_08
Patent number
US04284780

Reaction notes

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