[CH:1]([C:3]1[CH:4]=[C:5]([B:9]([OH:11])[OH:10])[CH:6]=[CH:7][CH:8]=1)=O.[CH3:12][N:13]1[CH2:18][CH2:17][NH:16][CH2:15][CH2:14]1.C(O)(=O)C.[BH-](OC(C)=O)(OC(C)=O)OC(C)=O.[Na+]>C(Cl)Cl>[CH3:12][N:13]1[CH2:18][CH2:17][N:16]([CH2:1][C:3]2[CH:4]=[C:5]([B:9]([OH:11])[OH:10])[CH:6]=[CH:7][CH:8]=2)[CH2:15][CH2:14]1A solution of 3-Formylphenylboronic acid (1 eq, 2 mmol, 0.3 g) in dry DCM (7 ml) under an inert atmosphere of argon is treated with 1-methyl-piperazine (1.2 eq, 2.4 mmol, 0.266 ml) followed by acetic acid (1.2 eq, 2.4 mmol, 0.14 ml) and NaBH(OAc)3 (1.6 eq, 3.2 mmol, 0.678 mg) and the resulting mixture is stirred at room temperature for 3 hours. The reaction is quenched by addition of water and is then extracted with DCM. The organic extracts are concentrated in vacuo and the crude residue is purified by flash chromatography on silica eluting with MeOH/DCM (0 to 100% MeOH in DCM) followed by 2M NH3 in MeOH. The appropriate fractions are combined and concentrated in vacuo to afford the title compound; [M+H]+=235.
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