Allyl bromide → N,N-Diethylbenzamide

HRID 538269

Reaction equation

HRID 538269 reaction equation
[CH:1]([N:14]1[CH2:19][CH2:18]N[CH2:16][CH2:15]1)(C1C=CC=CC=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(Br)C=C.C(=O)([O-])[O-:25].[Na+].[Na+]>O1CCCC1>[CH2:15]([N:14]([CH2:19][CH3:18])[C:1](=[O:25])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1)[CH3:16]

Participants

5

Reactant 3

HCID 7841Allyl bromideHCID 10340Sodium CarbonateHCID 70048Benzhydrylpiperazine

Product 1

HCID 15542N,N-Diethylbenzamide

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

The mixture of benzhydrylpiperazine epimers (7.6 g, 14.9 mmol) was dissolved in 50 mL of dry tetrahydrofuran with 1.6 mL (18.6 mmol) of allyl bromide and 5.1 g (36.9 mmol) of sodium carbonate and stirred at room temperature under nitrogen for 2 days. The reaction solution was poured into ice water/ethyl acetate and separated. The organic layer was dried over sodium sulfate, and concentrated in vacuo. The residue was dissolved in a small amount of dichloromethane and placed on a column of silica gel. The diastereomers were separated by elution with a stepwise gradient of ethanol in dichloromethane. The first isomer was eluted with 1.3% ethanol in dichloromethane, and the second isomer was obtained with 1.6% ethanol in dichloromethane. Fractions containing the second isomer were combined and the solvent removed in vacuo to give 1.44 g of 4-(αR)-α-((2R,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-(tert-butyldimethylsilyloxy)benzyl)-N,N-diethylbenzamide as a brown oil.

Workup

  1. customseparated
  2. dry with materialThe organic layer was dried over sodium sulfate
  3. concentrationconcentrated in vacuo
  4. dissolutionThe residue was dissolved in a small amount of dichloromethane
  5. customThe diastereomers were separated by elution with a stepwise gradient of ethanol in dichloromethane
  6. washThe first isomer was eluted with 1.3% ethanol in dichloromethane
  7. customthe second isomer was obtained with 1.6% ethanol in dichloromethane
  8. additionFractions containing the second isomer
  9. customthe solvent removed in vacuo

Sources & evidence

ORD record
ord-405eaa2d14644a6b99fa266ea55b0770
Source dataset
uspto-grants-2014_10
Patent number
US08865721B2

Linked notes

Loading…