methyl 2-piperidin-4-ylacetate

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

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

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 N-Boc-β-n-butyl-α,α-dimethyl-β-alanine (1.68 g, 6.13 mmol) in dichloromethane (30 ml) was added HATU reagent (2.8 g, 7.37 mmol) and di-i-propylethylamine (6.58 ml, 36.8 mmol) under cooling with ice. After being stirred for 30 min, to the reaction mixture was added 4-piperidineacetic acid methyl ester (1.45 g, 9.19 mmol) and stirred overnight at room temperature. After the solvent was distilled off, the resulting residue was dissolved into ethyl acetate and washed with 5% aqueous citric acid, 5% aqueous sodium bicarbonate, and brine for three times respectively. The organic layer was dried over anhydrous sodium sulfate. After the solvent was distilled off, the residue was subjected to the silica gel column chromatography (2.2×20 cm) and eluted with hexane:ethyl acetate=2:1 to give powder of N-Boc-β-n-butyl-α,α-dimethyl-β-alanyl-piperidineacetic acid methyl ester (1.70 g, 67.2%). under cooling with ice stirred overnight at room temperature After the solvent was distilled off the resulting residue was dissolved into ethyl acetate washed with 5% aqueous citric acid, 5% aqueous sodium bicarbonate, and brine for three times respectively The organic layer was dried over anhydrous sodium sulfate After the solvent was distilled off eluted with hexane

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

Procedure: N-4-Cyanobenzoyl-β-m-chlorophenyl-α,α-dimethyl-β-alanine (300 mg, 0.84 mmol) was dissolved in methylene chloride (30 ml). To the resulting solution, BOP reagent (409 mg, 0.92 mmol) and triethylamine (1 ml) were added under cooling with ice and the mixture was stirred for 30 minutes. To the reaction mixture was added 4-piperidineacetic acid methyl ester (572 mg, 3.36 mmol) and the resulting mixture was stirred overnight. After the solvent was distilled off, the residue was applied to a silica gel column (2.2×20 cm) and eluted with a mixed solution (hexane:ethyl acetate=3:1). The desired fractions were collected and the solvents were distilled off to yield an oil of N-4-cyanobenzoyl-β-m-chlorophenyl-α,α-dimethyl-β-alanyl-4-piperidineacetic acid methyl ester (270 mg, 65.0%). under cooling with ice the resulting mixture was stirred overnight After the solvent was distilled off eluted with a mixed solution (hexane:ethyl acetate=3:1) The desired fractions were collected the solvents were distilled off

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

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

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

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

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 4-{4-[(2-phenyl-5-trifluoromethyl-oxazole-4-carbonyl)-amino]-phenyl}-piperidine-1-carboxylic acid 4-nitro-phenyl ester (150 mg, 0.26 mmol) in 1-methyl-pyrrolidin-2-one (10 mL) at room temperature was added piperidin-4-yl-acetic acid methyl ester (0.04 g, 0.25 mmol) followed by N,N-diisopropylethylamine (0.14 mL, 0.8 mmol). The mixture was stirred in a 90° C. oil bath overnight. The mixture was blown to dryness and the crude was purified by flash chromatography (Merck silica gel 60, 230-400 mesh, gradient elution with 0%-60% ethyl acetate in hexane) to give [1-(4-{4-[(2-phenyl-5-trifluoromethyl-oxazole-4-carbonyl)-amino]-phenyl}-piperidine-1-carbonyl)-piperidin-4-yl]-acetic acid methyl ester (70 mg). LCMS calcd for C31H33F3N4O5 (m/e) 598, obsd 599 (M+H). the crude was purified by flash chromatography (Merck silica gel 60, 230-400 mesh, gradient elution with 0%-60% ethyl acetate in hexane)

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 2-chloro-5-nitropyridine (476 mg, 3.0 mmol) and 4-piperidine acetic acid methyl ester (471 mg, 3.0 mmol) in tetrahydrofuran (10 mL) was added diisopropylethylamine (1.0 mL, 5.74 mmol). The mixture was heated in a microwave at 120° C. for 30 minutes. The mixture was evaporated to dryness and extracted with ethyl acetate and water. The organic layer was dried over sodium sulfate and solvents were evaporated. The residue was purified using flash chromatography (eluting with ethyl acetate and hexanes) to give (5′-nitro-3,4,5,6-tetrahydro-2H-[1,2′]bipyridinyl-4-yl)-acetic acid methyl ester as a yellow solid. The NMR spectrum obtained on the sample is compatible with its structure. The mixture was evaporated to dryness extracted with ethyl acetate and water The organic layer was dried over sodium sulfate and solvents were evaporated The residue was purified flash chromatography (eluting with ethyl acetate and hexanes)

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 2-chloro-5-nitropyridine (476 mg, 3.0 mmol) and 4-piperidine acetic acid methyl ester (471 mg, 3.0 mmol) in tetrahydrofuran (10 mL) was added diisopropylethylamine (1.0 mL, 5.74 mmol). The mixture was heated in a microwave at 120° C. for 30 minutes. The mixture was evaporated to dryness and extracted with ethyl acetate and water. The organic layer was dried over sodium sulfate and solvents were evaporated. The residue was purified using flash chromatography (eluting with ethyl acetate and hexanes) to give (5′-nitro-3,4,5,6-tetrahydro-2H-[1,2′]bipyridinyl-4-yl)-acetic acid methyl ester as a yellow solid. The NMR spectrum obtained on the sample is compatible with its structure. The mixture was evaporated to dryness extracted with ethyl acetate and water The organic layer was dried over sodium sulfate and solvents were evaporated The residue was purified flash chromatography (eluting with ethyl acetate and hexanes)