1-methoxypiperidin-4-one

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 10 g of N-methoxy-4-piperidone (J. Org. Chem. 1961, 26, 1867-74) in 240 ml ammoniumhydroxide 25% in water there are added 6.2 g of ammoniumchloride and 4.6 g of sodium cyanide. After stirring for 18 h at 25° C. the reaction mixture is diluted with 200 ml water and extracted with ethyl acetate. The organic phase is separated, dried over sodium sulphate, filtered and evaporated. 8.25 g of 4-amino-1-methoxy-piperidine-4-carbonitrile is obtained as light brow oil, which is used without further purification in the next step. extracted with ethyl acetate The organic phase is separated dried over sodium sulphate filtered evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of cyclopropylamine (1.4 ml, 1.14 g, 20.0 mmol) in methanol (20 ml) at 0° C. was added 1N hydrochloric acid (20 ml, 20.0 mmol) dropwise and the mixture was stirred at room temperature for 30 minutes. 1-Methoxy-piperidin-4-one [prepared according to Journal of Organic Chemistry (1961), 26, 1867-74] (2.58 g, 20.0 mmol), followed 10 minutes later by potassium cyanide (1.3 g, 20.0 mmol) in water (10 ml) were then added dropwise at 0° C. The reaction mixture was warmed to room temperature and stirred overnight, diluted with water and diethyl ether, the layers separated and the aqueous phase thoroughly extracted with diethyl ether. The combined organic layers were washed with brine, dried over sodium sulfate and evaporated. Yield: 3.19 g of 4-cyclopropylamino-1-methoxy-piperidine-4-carbonitrile (title compound P5.2) as an oil. This material was used without further purification in the next step. were then added dropwise at 0° C The reaction mixture was warmed to room temperature stirred overnight the layers separated the aqueous phase thoroughly extracted with diethyl ether The combined organic layers were washed with brine dried over sodium sulfate evaporated This material was used without further purification in the next step

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1-methoxy-piperidin-4-one [prepared according to Journal of Organic Chemistry (1961), 26, 1867-74] (100 g, 0.77 mol), aqueous methylamine (40 wt. % in H2O, 86 ml) and methylamine hydrochloride (57.5 g, 0.85 mol) in water (700 ml) at 0° C. was added a solution of potassium cyanide (55.5 g, 0.85 mol) in water (150 ml) dropwise over one hour. The reaction mixture was stirred at room temperature for two days. Over the next five days, the mixture was further treated with methylamine hydrochloride (5×2.6 g, total 13.0 g), aqueous methylamine (5×4.3 ml, total 21.5 ml) and potassium cyanide (5×2.5 g, total 12.5 g), and stirring continued at room temperature until the reaction was judged complete by thin layer chromatography. The aqueous reaction mixture was extracted with dichloromethane (1×500 ml, and 4×200 ml), the combined organic phases dried over sodium sulfate and evaporated. Yield: 113.0 g of 1-methoxy-4-methylamino-piperidine-4-carbonitrile (compound P5.1) as a red liquid. This material was used without further purification in the next step. stirring continued at room temperature until the reaction The aqueous reaction mixture was extracted with dichloromethane (1×500 ml, and 4×200 ml) the combined organic phases dried over sodium sulfate evaporated This material was used without further purification in the next step

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1-methoxy-piperidin-4-one [prepared according to Journal of Organic Chemistry (1961), 26, 1867-74] (100 g, 0.77 mol), aqueous methylamine (40 wt. % in H2O, 86 ml) and methylamine hydrochloride (57.5 g, 0.85 mol) in water (700 ml) at 0° C. was added a solution of potassium cyanide (55.5 g, 0.85 mol) in water (150 ml) dropwise over one hour. The reaction mixture was stirred at room temperature for two days. Over the next five days, the mixture was further treated with methylamine hydrochloride (5×2.6 g, total 13.0 g), aqueous methylamine (5×4.3 ml, total 21.5 ml) and potassium cyanide (5×2.5 g, total 12.5 g), and stirring continued at room temperature until the reaction was judged complete by thin layer chromatography. The aqueous reaction mixture was extracted with dichloromethane (1×500 ml, and 4×200 ml), the combined organic phases dried over sodium sulfate and evaporated. Yield: 113.0 g of 1-methoxy-4-methylamino-piperidine-4-carbonitrile (compound P5.1) as a red liquid. This material was used without further purification in the next step. stirring continued at room temperature until the reaction The aqueous reaction mixture was extracted with dichloromethane (1×500 ml, and 4×200 ml) the combined organic phases dried over sodium sulfate evaporated This material was used without further purification in the next step

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 10 g of N-methoxy-4-piperidone (Journal of Organic Chemistry (1961), 26, 1867-74) in 240 ml of ammonium hydroxide (25% in water) was added 6.2 g of ammonium chloride and 4.6 g of sodium cyanide. After stirring for 18 hours at 25° C. the reaction mixture was diluted with 200 ml of water and extracted with ethyl acetate. The organic phase was separated, dried over sodium sulfate and evaporated. 8.25 g of 4-amino-1-methoxy-piperidine-4-carbonitrile was obtained as a light brown oil, which was used without further purification in the next step. extracted with ethyl acetate The organic phase was separated dried over sodium sulfate evaporated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1-methoxy-piperidin-4-one [prepared according to Journal of Organic Chemistry (1961), 26, 1867-74] (15.0 g, 116.1 mmol) in ethanol (430 ml) was added sodium borohydride 96% (2.29 g, 58.1 mmol) in portions. The reaction mixture was stirred at room temperature for 5 hours, evaporated to half of its volume, poured on cold saturated aqueous ammonium chloride and thoroughly extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate and concentrated. The residue was purified by chromatography on silica gel (ethyl acetate). Yield: 10.9 g of 1-methoxy-piperidin-4-ol as a liquid. evaporated to half of its volume poured on cold saturated aqueous ammonium chloride thoroughly extracted with ethyl acetate The combined organic layers were washed with brine dried over sodium sulfate concentrated The residue was purified by chromatography on silica gel (ethyl acetate)

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of cyclopropylamine (1.4 ml, 1.14 g, 20.0 mmol) in methanol (20 ml) at 0° C. was added 1N hydrochloric acid (20 ml, 20.0 mmol) dropwise and the mixture was stirred at room temperature for 30 minutes. 1-Methoxy-piperidin-4-one [prepared according to Journal of Organic Chemistry (1961), 26, 1867-74] (2.58 g, 20.0 mmol), followed 10 minutes later by potassium cyanide (1.3 g, 20.0 mmol) in water (10 ml) were then added dropwise at 0° C. The reaction mixture was warmed to room temperature and stirred overnight, diluted with water and diethyl ether, the layers separated and the aqueous phase thoroughly extracted with diethyl ether. The combined organic layers were washed with brine, dried over sodium sulfate and evaporated. Yield: 3.19 g of 4-cyclopropylamino-1-methoxy-piperidine-4-carbonitrile (title compound P5.2) as an oil. This material was used without further purification in the next step. were then added dropwise at 0° C The reaction mixture was warmed to room temperature stirred overnight the layers separated the aqueous phase thoroughly extracted with diethyl ether The combined organic layers were washed with brine dried over sodium sulfate evaporated This material was used without further purification in the next step

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1-methoxy-piperidin-4-one [prepared according to Journal of Organic Chemistry (1961), 26, 1867-74] (100 g, 0.77 mol), aqueous methylamine (40 wt. % in H2O, 86 ml) and methylamine hydrochloride (57.5 g, 0.85 mol) in water (700 ml) at 0° C. was added a solution of potassium cyanide (55.5 g, 0.85 mol) in water (150 ml) dropwise over one hour. The reaction mixture was stirred at room temperature for two days. Over the next five days, the mixture was further treated with methylamine hydrochloride (5×2.6 g, total 13.0 g), aqueous methylamine (5×4.3 ml, total 21.5 ml) and potassium cyanide (5×2.5 g, total 12.5 g), and stirring continued at room temperature until the reaction was judged complete by thin layer chromatography. The aqueous reaction mixture was extracted with dichloromethane (1×500 ml, and 4×200 ml), the combined organic phases dried over sodium sulfate and evaporated. Yield: 113.0 g of 1-methoxy-4-methylamino-piperidine-4-carbonitrile (compound P5.1) as a red liquid. This material was used without further purification in the next step. stirring continued at room temperature until the reaction The aqueous reaction mixture was extracted with dichloromethane (1×500 ml, and 4×200 ml) the combined organic phases dried over sodium sulfate evaporated This material was used without further purification in the next step

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Under an atmosphere of argon, 200 ml ethanol was cooled to 10° C. and 3.7 g sodium borohydride was added. A solution of 25 g 1-methoxy-piperidin-4-one (prepared according to J. Org. Chem. 1961, 26, 1867-74) in 200 ml ethanol was added to the stirred suspension, while the temperature was kept in the range of 15-20° C. Then the mixture was stirred at ambient temperature for 3 hours. 50 ml aqueous ammonium chloride was added slowly and then the solvent evaporated. The residue was purified by chromatography on silica gel, using ethyl acetate as a solvent. Thus, 22.8 g 1-methoxy-piperidin-4-ol was obtained. was kept in the range of 15-20° C the solvent evaporated The residue was purified by chromatography on silica gel

Conditions: temp:-60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of (methoxymethyl)triphenylphosphonium chloride (35.8 g, 104 mmol) in THF (160 mL) was cooled to −60° C. and treated with a 2.5M solution of n-BuLi in hexane (42 mL, 105 mmol). After 20 min, a solution of 1-methoxy-piperidin-4-one [prepared according to Journal of Organic Chemistry (1961), 26, 1867-74] (9 g, 70 mmol) in THF (80 mL) was added, and the reaction mixture was allowed to warm to 10° C. over 2 h. The reaction was quenched with saturated ammonium chloride, and the solvent was removed under reduced pressure. The residue was partitioned between water and chloroform and the organic layer dried with sodium sulfate and evaporated. The residue was purified by column chromatography on silica gel. Yield: 9.2 g of 1-methoxy-4-methoxymethylene-piperidine as an oil. to warm to 10° C. over 2 h The reaction was quenched with saturated ammonium chloride the solvent was removed under reduced pressure The residue was partitioned between water and chloroform the organic layer dried with sodium sulfate evaporated The residue was purified by column chromatography on silica gel