[CH3:1][CH:2]([O:4][C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=1[N:11]1[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]1)[CH3:3].[C:17]([C:20]1[CH:21]=[C:22]([CH:25]=[CH:26][CH:27]=1)[C:23]#[N:24])(=O)[CH3:18].[BH4-].[Na+]>CC(C)[O-].[Ti+4].CC(C)[O-].CC(C)[O-].CC(C)[O-].CO>[CH3:3][CH:2]([O:4][C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=1[N:11]1[CH2:12][CH2:13][N:14]([CH:17]([C:20]2[CH:21]=[C:22]([CH:25]=[CH:26][CH:27]=2)[C:23]#[N:24])[CH3:18])[CH2:15][CH2:16]1)[CH3:1]A mixture of 1-[2-(methylethoxy)phenyl]piperazine (IPP, 7.28 g, 0.033 mol), 3-acetylbenzonitrile (4.80 g, 0.033 mol), and titanium isopropoxide (11.74 g, 0.041 mol) was stirred at room temperature for 2 h, heated to 80° C. for several minutes, and then cooled to room temperature. Methanol (150 mL) was added and the mixture was heated to dissolve most of the solids. After cooling to room temperature, sodium borohydride (2.27 g, 0.060 mol) was added in portions and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated on a rotary evaporator and the residue was partitioned between 3N NaOH/CH2Cl2. The organic layer was separated, dried (K2CO3), filtered, and evaporated to an oily residue which was passed through flash grade silica using 4:1 hexane:EtOAc as eluant to give 3-[1-[4-[2-(1-methylethoxy)phenyl]-1-piperazinyl]ethyl]benzonitrile as an oil (1.55 g, 13.5%).
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