Methyl Isocyanate → 4-(4-Fluorobenzyl)-N-methyl-3-oxopiperazine-1-carboxamide
Reaction equation
[F:1][C:2]1[CH:15]=[CH:14][C:5]([CH2:6][N:7]2[CH2:12][CH2:11][NH:10][CH2:9][C:8]2=[O:13])=[CH:4][CH:3]=1.[CH3:16][N:17]=[C:18]=[O:19]>C1COCC1>[F:1][C:2]1[CH:15]=[CH:14][C:5]([CH2:6][N:7]2[CH2:12][CH2:11][N:10]([C:18]([NH:17][CH3:16])=[O:19])[CH2:9][C:8]2=[O:13])=[CH:4][CH:3]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
1-(4-Fluorobenzyl)piperazin-2-one (0.40 g, 1.9 mmol, Example 1, Step 4) was dissolved in anhydrous THF (20 mL) under nitrogen and methyl isocyanate (0.96 mL, 1.9 mmol, 2M solution in THF) was added. The reaction was allowed to stir for two hours at room temperature. The solvent was removed in vacuo and the residue was purified by flash chromatography on silica gel using a 0-5% MeOH/CHCl3 gradient elution. Collection and concentration of the appropriate fractions provided the title compound as a white solid. 1H NMR (400 MHz, d6 DMSO) δ 7.29 (m, 2H), 7.16 (m, 2H), 6.55 (d, 1H, J=4.2 Hz), 4.51 (s, 2H), 3.97 (s, 2H), 3.50 (t, 2H, J=5.4 Hz), 3.22 (t, 2H, J=5.4 Hz), and 2.56 (d, 3H, J=4.4 Hz); ES MS (M+1)=266.