Methyl iodide → 4-Benzyl-1-methylpiperazin-2-one

Reaction equation

[H-].[Na+].[C:3]1([CH2:9][N:10]2[CH2:15][CH2:14][NH:13][C:12](=[O:16])[CH2:11]2)[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.[CH3:17]I>C1COCC1>[CH3:17][N:13]1[CH2:14][CH2:15][N:10]([CH2:9][C:3]2[CH:4]=[CH:5][CH:6]=[CH:7][CH:8]=2)[CH2:11][C:12]1=[O:16]

Participants

Procedure

Sodium hydride (50% in oil, 10.4 g., 0.22 mole) is added to a stirred solution of 4-(phenylmethyl)piperazinone (Example 45, 38.0 g., 0.20 mole) in THF (2.0 l.). After 1 hour mehyl iodide (80.0 g., 0.75 mole) is added and the reaction solution is refluxed for 2.5 hours. The THF is removed under reduced pressure and the residual oil is partitioned between chloroform and water. Evaporation of the chloroform gives an oil which is chromatographed on silica gel to give the title compound, which is converted to the p-TSA salt, m.p. 138°-140°.