Potassium Carbonate → 2-(4-Benzylpiperidino)-2'-methylpropiophenone

HRID 2308754Notes

Reaction equation

HRID 2308754 reaction equation
Br[CH:2]([CH3:12])[C:3]([C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=1[CH3:11])=[O:4].C(=O)([O-])[O-].[K+].[K+].[CH2:19]([CH:26]1[CH2:31][CH2:30][NH:29][CH2:28][CH2:27]1)[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1>C(#N)C>[CH2:19]([CH:26]1[CH2:31][CH2:30][N:29]([CH:2]([CH3:12])[C:3]([C:5]2[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=2[CH3:11])=[O:4])[CH2:28][CH2:27]1)[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 317384-BenzylpiperidineHCID 235027102-Bromo-1-o-tolyl-propan-1-one

Product 1

HCID 201874922-(4-Benzylpiperidino)-2'-methylpropiophenone

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

A mixture of 25 g of 2-bromo-2'-methylpropiophenone, 70 ml of dry acetonitrile, 30 g of potassium carbonate and 19 g of 4-benzylpiperidine is stirred for 4 hours at ambient temperature. It is filtered in order to separate off the inorganic residue, and the filtrate is diluted with 200 ml of diethyl ether, which causes precipitation of 4-benzylpiperidine hydrobromide. This is filtered off; the filtrate deposits a second crop of hydrobromide, which is also separated off. The filtrate is then acidified with 300 ml of 3N hydrochloric acid. The intermediate propiophenone hydrochloride is an oil which is insoluble in both phases. The acid aqueous phase is extracted twice with methylene chloride, the extract is washed with water, and aqueous ammonia solution is added. The mixture is stirred and left to separate, the organic phase is dried, filtered and treated with about 100 g of silica in order to retain the traces of 4-benzylpiperidine, the mixture is filtered and the filtrate is evaporated. 10.9 g of an oil are collected.

Workup

  1. filtrationIt is filtered in order
  2. customto separate off the inorganic residue
  3. additionthe filtrate is diluted with 200 ml of diethyl ether, which
  4. customprecipitation of 4-benzylpiperidine hydrobromide
  5. filtrationThis is filtered off
  6. customthe filtrate deposits a second crop of hydrobromide, which is also separated off
  7. extractionThe acid aqueous phase is extracted twice with methylene chloride
  8. washthe extract is washed with water, and aqueous ammonia solution
  9. additionis added
  10. stirringThe mixture is stirred
  11. waitleft
  12. customto separate
  13. customthe organic phase is dried
  14. filtrationfiltered
  15. additiontreated with about 100 g of silica in order
  16. filtrationthe mixture is filtered
  17. customthe filtrate is evaporated
  18. custom10.9 g of an oil are collected

Sources & evidence

ORD record
ord-4b867292afba4269ad16dbfc8ffb7e6d
Source dataset
uspto-grants-1987_09
Patent number
US04690931

Reaction notes

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