甲基 (2R,4S)-4-羟基哌啶-2-羧酸乙酯

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a solution of the title compound of Example 1, Step E (4.54 g, 15.2 mmol) in dichloromethane (20 mL) was added dropwise a solution of methyl cis-4-hydroxy-2-piperidinecarboxylate (2.41 g, 15.2 mmol, prepared as described in J. Org. Chem. (1991), 4084) in dichloromethane (20 mL) at room temperature. The reaction was stirred at room temperature for 20 hours, quenched by the addition of water, and the aqueous layer was extracted with dichloromethane. The combined organic layers were washed with water and dried over magnesium sulfate. The solvent was removed under reduced pressure and the title compound of Step A, a compound of this invention, was isolated as a foam by flash chromatography (4.98 g). 1H NMR (Me2SO-d6) δ 10.1 (br s, 1H), 7.75 (m, 1H), 7.4 (dd, 1H), 5.1 (m, 1H), 4.9 (s, 2H), 4.1-3.9 (m, 3H), 3.75 (m, 1H), 2.95 (m, 1H), 2.05 (m, 1H), 1.9 (br d, 1H), 1.2 (m, 1H). quenched by the addition of water the aqueous layer was extracted with dichloromethane The combined organic layers were washed with water dried over magnesium sulfate The solvent was removed under reduced pressure

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of (1S,5R)-2-((S)-1-phenylethyl)-6-oxa-2-azabicyclo[3.2.1]octan-7-one (2.95 g) and 10% palladium on activated carbon (570 mg) in methanol (75 mL) was stirred at room temperature for 6 hr under hydrogen (3.5 kgf/cm2). The catalysts were removed by filtration and washed with methanol. The combined organic layers were evaporated in vacuo. A mixture of the residue and 10% palladium on activated carbon (500 mg) in methanol (75 mL) was stirred at room temperature for 8 hr under hydrogen (3.5 kgf/cm2). The catalysts were removed by filtration and washed with methanol. The combined organic layers were evaporated in vacuo. The mixture of the residue and 10% palladium on activated carbon (504 mg) in methanol (75 mL) was stirred at room temperature for 8 hr under hydrogen (4.0 kgf/cm2). The catalysts were removed by filtration and washed with methanol. The combined organic layers were evaporated in vacuo to give the title compound (2.11 g): 1H NMR (400 MHz, CDCl3) δ 1.32-1.49 (m, 2H), 1.83 (br s, 2H), 1.93-1.95 (m, 1H), 2.27-2.32 (m, 1H), 2.61-2.69 (m, 1H), 3.22 (dt, J=12.7, 3.9 Hz, 1H), 3.39 (dd, J=2.9, 10.7 Hz, 1H), 3.71-3.78 (m, 1H), and 3.75 (m, 3H). The catalysts were removed by filtration washed with methanol The combined organic layers were evaporated in vacuo A mixture of the residue and 10% palladium on activated carbon (500 mg) in methanol (75 mL) was stirred at room temperature for 8 hr under hydrogen (3.5 kgf/cm2) The catalysts were removed by filtration washed with methanol The combined organic layers were evaporated in vacuo The mixture of the residue and 10% palladium on activated carbon (504 mg) in methanol (75 mL) was stirred at room temperature for 8 hr under hydrogen (4.0 kgf/cm2) The catalysts were removed by filtration washed with methanol The combined organic layers were evaporated in vacuo

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a solution of the title compound of Example 1, Step E (4.54 g, 15.2 mmol) in dichloromethane (20 mL) was added dropwise a solution of methyl cis-4-hydroxy-2-piperidinecarboxylate (2.41 g, 15.2 mmol, prepared as described in J. Org. Chem. (1991), 4084) in dichloromethane (20 mL) at room temperature. The reaction was stirred at room temperature for 20 hours, quenched by the addition of water, and the aqueous layer was extracted with dichloromethane. The combined organic layers were washed with water and dried over magnesium sulfate. The solvent was removed under reduced pressure and the title compound of Step A, a compound of this invention, was isolated as a foam by flash chromatography (4.98 g). 1H NMR (Me2SO-d6) δ 10.1 (br s, 1H), 7.75 (m, 1H), 7.4 (dd, 1H), 5.1 (m, 1H), 4.9 (s, 2H), 4.1-3.9 (m, 3H), 3.75 (m, 1H), 2.95 (m, 1H), 2.05 (m, 1H), 1.9 (br d, 1H), 1.2 (m, 1H). quenched by the addition of water the aqueous layer was extracted with dichloromethane The combined organic layers were washed with water dried over magnesium sulfate The solvent was removed under reduced pressure