Methyl iodide → 4-Benzyl-1-methyl-2-oxo-3-phenylpiperazine

HRID 1824451Notes

Reaction equation

HRID 1824451 reaction equation
[H-].[Na+].[CH2:3]([N:10]1[CH2:15][CH2:14][NH:13][C:12](=[O:16])[CH:11]1[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1)[C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1.[CH3:23]I>CN(C)C=O.O>[CH2:3]([N:10]1[CH2:15][CH2:14][N:13]([CH3:23])[C:12](=[O:16])[CH:11]1[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1)[C:4]1[CH:5]=[CH:6][CH:7]=[CH:8][CH:9]=1

Participants

6

Reactant 3

HCID 6328Methyl iodideHCID 24758Sodium hydrideHCID 2506754-Benzyl-3-phenylpiperazin-2-one

Product 1

HCID 113465264-Benzyl-1-methyl-2-oxo-3-phenylpiperazineYield 93.8%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent2×

Conditions

Temperature
10 °C

Procedure

15.3 g of sodium hydride (65% dispersion in mineral oil, 0.414 moles) was suspended in 250 ml of N,N-dimethylformamide at 10° C. To this suspension, 100 g of 4-benzyl-2-oxo-3-phenylpiperazine (0.376 moles) was added portionwise over a period of 30 min and stirred for 15 min. A solution of 64 g of methyl iodide (0.45 moles) in 50 ml of N,N-dimethylformamide was added slowly in 45 min maintaining the temperature below 25° C. and maintained for 1 hour. After completion of the reaction, mass was poured slowly in 1000 ml of cold water (15° C.). The product was extracted with toluene (1×500 ml, 1×300 ml) from aqueous phase. Toluene layer was washed with water (2×200 ml) and concentrated. To the residue, 250 ml of cyclohexane was added and cooled to 10° C. with stirring. Filtered the product and washed with precooled cyclohexane to obtain 98.5 g of 4-benzyl-1-methyl-2-oxo-3-phenylpiperazine product (yield: 93.8%, purity: 99.15 by HPLC)

Workup

  1. temperaturemaintaining the temperature below 25° C.
  2. temperaturemaintained for 1 hour
  3. customAfter completion of the reaction, mass
  4. extractionThe product was extracted with toluene (1×500 ml, 1×300 ml) from aqueous phase
  5. washToluene layer was washed with water (2×200 ml)
  6. concentrationconcentrated
  7. additionTo the residue, 250 ml of cyclohexane was added
  8. stirringwith stirring
  9. filtrationFiltered the product
  10. washwashed with precooled cyclohexane

Sources & evidence

ORD record
ord-96051f4f3ac74123abbdc943e26c6ef7
Source dataset
uspto-grants-2006_05
Patent number
US07041826B2

Reaction notes

Loading…