Cyanogen Bromide → 4-(4-Fluorobenzyl)-3-oxopiperazine-1-carbonitrile
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.[N:16]#[C:17]Br>C(Cl)Cl>[F:1][C:2]1[CH:15]=[CH:14][C:5]([CH2:6][N:7]2[CH2:12][CH2:11][N:10]([C:17]#[N:16])[CH2:9][C:8]2=[O:13])=[CH:4][CH:3]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To 1-(4-Fluorobenzyl)piperazin-2-one (0.50 g, 2.40 mmol, Example 1, Step 4) dissolved in methylene chloride (75 mL) was added diisopropylethylaime (0.84 mL, 4.80 mmol) and cyanogen bromide (0.28 g, 2.64 mmol) and the resultant solution was stirred overnight 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. The pure fractions were concentrated to yield the title compound as a white solid. 1H NMR (400 MHz, d6 DMSO) δ 7.31 (m, 2H), 7.18 (m, 2H), 4.54 (s, 2H), 3.98 (s, 2H), 3.49 (m, 2H), and 3.33 (m, 2H); ES MS (M+1)=234.3.