Propargyl bromide → HCID 23468929, compound

HRID 128305Notes

Reaction equation

HRID 128305 reaction equation
[CH3:1][C:2]1[O:3][C:4]2[CH:10]=[CH:9][C:8]([CH:11]3[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]3)=[CH:7][C:5]=2[CH:6]=1.[CH2:17](Br)[C:18]#[CH:19]>C(=O)([O-])[O-].[K+].[K+].CO>[CH2:19]([N:14]1[CH2:15][CH2:16][CH:11]([C:8]2[CH:9]=[CH:10][C:4]3[O:3][C:2]([CH3:1])=[CH:6][C:5]=3[CH:7]=2)[CH2:12][CH2:13]1)[C:18]#[CH:17]

Participants

5

Reactant 2

HCID 7842Propargyl bromide2×HCID 23468881HCID 23468881, compound

Product 1

HCID 23468929HCID 23468929, compound

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 11430Potassium CarbonateSolvent

Procedure

2.8 g (0.013 mol) of 4-(2-methyl-5-benzofuranyl)-piperidine (c.f. Example 12) and 2.4 g (0.02 mol) of 2-propynyl bromide are dissolved in a suspension of 10 g of potassium carbonate in 120 ml of methanol and the solution is stirred at room temperature. After 24 hours, a further 0.24 g of 2-propynyl bromide is added and the reaction mixture is stirred at room temperature for a further 24 hours. Thereafter, it is filtered, the residue on the filter is washed with ethyl acetate and the combined filtrates are evaporated to dryness under a waterpump vacuum. The residue is dissolved again in ethyl acetate and the solution is washed three times with water, dried over sodium sulfate and evaporated to dryness under a waterpump vacuum. The resulting residue is chromatographed on 200 g of aluminium oxide (eluting agent: methylene chloride), whereupon, after evaporating off the solvent, crystalline 1-(2-propynyl)-4-(2-methyl-5-benzofuranyl)-piperidine is obtained. The hydrochloride, prepared from the base in a conventional manner, melts at 185°-187°.

Workup

  1. stirringthe reaction mixture is stirred at room temperature for a further 24 hours
  2. filtrationThereafter, it is filtered
  3. washthe residue on the filter is washed with ethyl acetate
  4. customthe combined filtrates are evaporated to dryness under a waterpump vacuum
  5. dissolutionThe residue is dissolved again in ethyl acetate
  6. washthe solution is washed three times with water
  7. dry with materialdried over sodium sulfate
  8. customevaporated to dryness under a waterpump vacuum
  9. customThe resulting residue is chromatographed on 200 g of aluminium oxide (eluting agent: methylene chloride), whereupon
  10. customafter evaporating off the solvent

Sources & evidence

ORD record
ord-a73dc486dac84a0f84d8c2fa29d3c92b
Source dataset
uspto-grants-1981_03
Patent number
US04259338

Reaction notes

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