5-[(1R)-1-phenylethyl]-5-azaspiro[2.4]heptane-4,7-dione

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of LiAlH4 (0.995 g, 26.2 mmol) in THF (40 mL) was added a solution of 5-((R)-α-methylbenzyl)-4,7-dioxo-5-azaspiro[2.4]heptane (3.0 g, 13.1 mmol) in THF (10 mL) at 0° C. The reaction mixture was stirred at 0° C. for 2 hrs, then warmed up to 50° C. and continued to stir for 6 hrs. The reaction mixture was then cooled to 0° C. and ethyl acetate (10 mL) and water (10 mL) were added. The suspension was filtered and the filtrate was concentrated in vacuo. The residue was purified by a silica gel column chromatography (1:3 (v/v) 2-butanol/n-hexane) to afford the title compound as colorless oil (2.4 g, 85%). warmed up to 50° C. to stir for 6 hrs The reaction mixture was then cooled to 0° C. The suspension was filtered the filtrate was concentrated in vacuo The residue was purified by a silica gel column chromatography (1:3 (v/v) 2-butanol/n-hexane)

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

Procedure: To a solution of ethyl 1-(2-bromoacetyl)cyclopropanecarboxylate (4.7 g, 20 mmol) in THF (60 mL) was added (R)-α-methylbenzylamine (2.9 g, 24 mmol) and Et3N (4.04 g, 40 mmol). After stirring at rt for 3 days, the reaction mixture was concentrated in vacuo, and the residue was extracted with ethyl acetate (50 mL×2) and washed with water (30 mL). The combined organic phases were dried over anhydrous Na2SO4, filtered and the filtrate was concentrated in vacuo. The residue was purified by a silica gel column chromatography (EtOAc) to afford the title compound as a light yellow solid (3.66 g, 80%). the reaction mixture was concentrated in vacuo the residue was extracted with ethyl acetate (50 mL×2) washed with water (30 mL) The combined organic phases were dried over anhydrous Na2SO4 filtered the filtrate was concentrated in vacuo The residue was purified by a silica gel column chromatography (EtOAc)

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

Procedure: A suspension of 1.5 g of compound 12 and 500 mg of lithium aluminum hydride in 30 ml of tetrahydrofuran was refluxed for 16 hours. 0.5 ml of water, 0.5 ml of 15% aqueous sodium hydroxide and 1.5 ml of water were added to the mixture in the mentioned order, and the mixture was stirred at room temperature for 30 minutes. The insoluble material was removed by filtration and the filtrate was concentrated to dryness to yield 1.4 g of 7-hydroxy-5-[1-(R)-phenylethyl]-5-azaspiro[2,4]heptane as a pale yellow oil. 5 ml of acetic anhydride and 5 ml of pyridine were added to 1.4 g of 7-hydroxy-5-[1-(R)-phenylethyl]-5-azaspiro[2,4]heptane which was cooled on an ice-bath. The mixture was stirred at room temperature for 3 hours. Ethyl acetate was added thereto and the solution was washed with saturated aqueous sodium bicarbonate and water, then, dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure to yield 1.6 g of 7-acetoxy-5-[1-(R)-phenylethyl]-5-azaspiro[2,4]heptane as a yellow oil. A mixture of 1.6 g of 7-acetoxy-5-[1-(R)-phenylethyl]-5-azaspiro[2,4]heptane and 1.2 g of palladium-on-carbon (50% water wet) in 20 ml of ethanol was shaken under 3.8 atm of pressured hydrogen atmosphere for 5 hours. During the reduction reaction, the reaction vessel was warmed by a tungsten lamp. The catalyst was removed by filtration and the solvent was removed under reduced pressure to give 880 mg of title compound 69 as an oil. was refluxed for 16 hours The insoluble material was removed by filtration the filtrate was concentrated to dryness

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of LiAlH4 (0.995 g, 26.2 mmol) in THF (40 mL) was added a solution of 5-((R)-α-methylbenzyl)-4,7-dioxo-5-azaspiro[2.4]heptane (3.0 g, 13.1 mmol) in THF (10 mL) at 0° C. The reaction mixture was stirred at 0° C. for 2 hrs, then warmed up to 50° C. and continued to stir for 6 hrs. The reaction mixture was then cooled to 0° C. and ethyl acetate (10 mL) and water (10 mL) were added. The suspension was filtered and the filtrate was concentrated in vacuo. The residue was purified by a silica gel column chromatography (1:3 (v/v) 2-butanol/n-hexane) to afford the title compound as colorless oil (2.4 g, 85%). warmed up to 50° C. to stir for 6 hrs The reaction mixture was then cooled to 0° C. The suspension was filtered the filtrate was concentrated in vacuo The residue was purified by a silica gel column chromatography (1:3 (v/v) 2-butanol/n-hexane)

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

Procedure: To a solution of ethyl 1-(2-bromoacetyl)cyclopropanecarboxylate (4.7 g, 20 mmol) in THF (60 mL) was added (R)-α-methylbenzylamine (2.9 g, 24 mmol) and Et3N (4.04 g, 40 mmol). After stirring at rt for 3 days, the reaction mixture was concentrated in vacuo, and the residue was extracted with ethyl acetate (50 mL×2) and washed with water (30 mL). The combined organic phases were dried over anhydrous Na2SO4, filtered and the filtrate was concentrated in vacuo. The residue was purified by a silica gel column chromatography (EtOAc) to afford the title compound as a light yellow solid (3.66 g, 80%). the reaction mixture was concentrated in vacuo the residue was extracted with ethyl acetate (50 mL×2) washed with water (30 mL) The combined organic phases were dried over anhydrous Na2SO4 filtered the filtrate was concentrated in vacuo The residue was purified by a silica gel column chromatography (EtOAc)

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

Procedure: A suspension of 1.5 g of compound 12 and 500 mg of lithium aluminum hydride in 30 ml of tetrahydrofuran was refluxed for 16 hours. 0.5 ml of water, 0.5 ml of 15% aqueous sodium hydroxide and 1.5 ml of water were added to the mixture in the mentioned order, and the mixture was stirred at room temperature for 30 minutes. The insoluble material was removed by filtration and the filtrate was concentrated to dryness to yield 1.4 g of 7-hydroxy-5-[1-(R)-phenylethyl]-5-azaspiro[2.4]heptane as a pale yellow oil. 5 ml of acetic anhydride and 5 ml of pyridine were added to 1.4 g of 7-hydroxy-5-[1-(R)-phenylethyl]-5-azaspiro[2.4]heptane which was cooled on an ice-bath. The mixture was stirred at room temperature for 3 hours. Ethyl acetate was added thereto and the solution was washed with saturated aqueous sodium bicarbonate and water, then, dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure to yield 1.6 g of 7-acetoxy-5-[1-(R)-phenylethyl]-5-azaspiro[2.4]heptane as a yellow oil. A mixture of 1.6 g of 7-acetoxy-5-[1-(R)-phenylethyl]-5-azaspiro[2.4]heptane and 1.2 g of palladium-on-carbon (50% water wet) in 20 ml of ethanol was shaken under 3.8 atm of pressured hydrogen atmosphere for 5 hours. During the reduction reaction, the reaction vessel was warmed by a tungsten lamp. The catalyst was removed by filtration and the solvent was removed under reduced pressure to give 880 mg of title compound 69 as an oil. was refluxed for 16 hours The insoluble material was removed by filtration the filtrate was concentrated to dryness

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of LiAlH4 (0.995 g, 26.2 mmol) in THF (40 mL) was added a solution of 5-((R)-α-methylbenzyl)-4,7-dioxo-5-azaspiro[2.4]heptane (3.0 g, 13.1 mmol) in THF (10 mL) at 0° C. The reaction mixture was stirred at 0° C. for 2 hrs, then warmed up to 50° C. and continued to stir for 6 hrs. The reaction mixture was then cooled to 0° C. and EtOAc (10 mL) and H2O (10 mL) were added. The suspension was filtered and the filtrate was concentrated in vacuo. The residue was purified by a silica gel column chromatography (1:3 (v/v) 2-butanol/n-hexane) to afford the title compound as colorless oil (2.4 g, 85%). warmed up to 50° C. to stir for 6 hrs The reaction mixture was then cooled to 0° C. The suspension was filtered the filtrate was concentrated in vacuo The residue was purified by a silica gel column chromatography (1:3 (v/v) 2-butanol/n-hexane)

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

Procedure: To a solution of ethyl 1-(2-bromoacetyl)cyclopropanecarboxylate (4.7 g, 20 mmol) in THF (60 mL) was added (R)-α-methylbenzylamine (2.9 g, 24 mmol) and Et3N (4.04 g, 40 mmol). After stirring at rt for 3 days, the reaction mixture was concentrated in vacuo, and the residue was extracted with EtOAc (50 mL×2) and washed with water (30 mL). The combined organic phases were dried over anhydrous Na2SO4, filtered and the filtrate was concentrated in vacuo. The residue was purified by a silica gel column chromatography (EtOAc) to afford the title compound as a yellow solid (3.66 g, 80%). the reaction mixture was concentrated in vacuo the residue was extracted with EtOAc (50 mL×2) washed with water (30 mL) The combined organic phases were dried over anhydrous Na2SO4 filtered the filtrate was concentrated in vacuo The residue was purified by a silica gel column chromatography (EtOAc)