反应详情

To an ice cooled solution of ethyl 4-(piperazin-1-yl)benzoate (1.23 g) and 1-methoxy-1,1′-bicyclohexane-4-one (916 mg) in a mixed solvent of methanol (20 ml), tetrahydrofuran (15 ml) and acetic acid (0.74 ml) was added sodium cyanoborohydride (301 mg) in a stream of nitrogen. The mixture was stirred at this temperature for 1.5 hours and at room temperature for 7.5 hours. The reaction mixture was quenched with saturated aqueous sodium hydrogen carbonate solution. Dichloromethane was added to the solution. The organic layer was taken, washed with sodium hydrogen carbonate solution and dried over magnesium sulfate. The magnesium sulfate was filtered off, and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel chromatography (3:1 hexane-methanol elution) to give 4-[4-(1-methoxy-1,1′-bicyclohexan-4-yl)piperazinyl]benzoic acid ethyl ester (801 mg).

1. customThe reaction mixture was quenched with saturated aqueous sodium hydrogen carbonate solution
2. additionDichloromethane was added to the solution
3. washwashed with sodium hydrogen carbonate solution
4. dry with materialdried over magnesium sulfate
5. filtrationThe magnesium sulfate was filtered off
6. concentrationthe filtrate was concentrated under reduced pressure
7. customThe residue was purified by silica gel chromatography (3:1 hexane-methanol elution)