tert-butyl piperidine-4-carboxylate

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

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

Conditions: temp:170.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1-Chloro-4-(3-chloro-4-methoxybenzyl)amino-6-cyanophthalazine (2 g) prepared in Example 1 and t-butyl isonipecotate (2 g) were dissolved in 20 ml of N-methyl-2-pyrrolidone. The obtained solution was heated at 170° C. for 5 hours and cooled, followed by the addition of water. The obtained mixture was extracted with ethyl acetate. The organic phase was washed with water, dried over anhydrous magnesium sulfate and concentrated in a vacuum. The obtained residue was subjected to silica gel column chromatography and eluted with toluene/tetrahydrofuran (10:1) to give 1.6 g of 1-(4-tert-butoxycarbonyl-piperidino)-4-(3-chloro-4-methoxybenzyl)amino-6-cyanophthalazine. cooled The obtained mixture was extracted with ethyl acetate The organic phase was washed with water dried over anhydrous magnesium sulfate concentrated in a vacuum eluted with toluene/tetrahydrofuran (10:1)

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

Procedure: 3.03 g of N-methylmorpholine are added to a solution of 2.91 g of 3-[4-(5-oxo-1,2,4-oxadiazolin-3-yl)phenyl]-2-oxo-5-oxazolidinecarboxylic acid [obtainable according to Example 3], 2.77 g of tert-butyl piperidine-4-carboxylate, 2.02 g of 1-hydroxybenzotriazole and 2.86 g of N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride in 20 ml of DMF, and the mixture is stirred at room temperature for 5 h. 200 ml of water are subsequently added dropwise with intensive stirring, the crystalline precipitate formed is separated off and taken up in 90 ml of dichloromethane, and the mixture is dried over Na2SO4. The solution is concentrated in vacuo, and the resulting oil is triturated with diethyl ether to give tert-butyl 1-{3-[4-(5-oxo-1,2,4-oxadiazolin-3-yl)phenyl]-2-oxo-5-oxazolidinylcarbonyl}piperidine-4carboxylate, m.p. 171°-175°. the crystalline precipitate formed is separated off the mixture is dried over Na2SO4 The solution is concentrated in vacuo the resulting oil is triturated with diethyl ether

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

Procedure: 3.03 g of N-methylmorpholine are added to a solution of 2.91 g of 3-[4-(5-oxo-1,2,4-oxadiazolin-3-yl)phenyl]-2-oxo-5-oxazolidinecarboxylic acid [obtainable according to Example 3], 2.77 g of tert-butyl piperidine-4-carboxylate, 2.02 g of 1-hydroxybenzotriazole and 2.86 g of N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride in 20 ml of DMF, and the mixture is stirred at room temperature for 5 h. 200 ml of water are subsequently added dropwise with intensive stirring, the crystalline precipitate formed is separated off and taken up in 90 ml of dichloromethane, and the mixture is dried over Na2SO4. The solution is concentrated in vacuo, and the resulting oil is triturated with diethyl ether to give tert-butyl 1-{3-[4-(5-oxo-1,2,4-oxadiazolin-3-yl)phenyl]-2-oxo-5-oxazolidinylcarbonyl}piperidine-4carboxylate, m.p. 171°-175°. the crystalline precipitate formed is separated off the mixture is dried over Na2SO4 The solution is concentrated in vacuo the resulting oil is triturated with diethyl ether

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

Procedure: To a solution of 1-benzyl 4-tert-butyl piperidine-1,4-dicarboxylate in EtOAc (0.1 M), a catalytic amount of Pd/C (5%) was added and the atmosphere in the reaction vessel charged with H2 (1 atmosphere). The reaction mixture was stirred vigorously at RT for 8 h. The solution was filtered and the filtrate concentrated in vacuo to afford the title compound (76%); MS (ES+) m/z 186(M+H)+ the atmosphere in the reaction vessel charged with H2 (1 atmosphere) The solution was filtered the filtrate concentrated in vacuo

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

Procedure: To a solution of 1-benzyl 4-tert-butyl piperidine-1,4-dicarboxylate in EtOAc (0.1 M), a catalytic amount of Pd/C (5%) was added and the atmosphere in the reaction vessel charged with H2 (1 atmosphere). The reaction mixture was stirred vigorously at RT for 8 h. The solution was filtered and the filtrate concentrated in vacuo to afford the title compound (76%); MS (ES+) m/z 186(M+H)+ the atmosphere in the reaction vessel charged with H2 (1 atmosphere) The solution was filtered the filtrate concentrated in vacuo

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

Procedure: To a suspension (39 mL) of tert-butyl piperidine-4-carboxylate (2.6 g) in acetonitrile was added diisopropylethylamine (4.4 mL), subsequently, benzyl bromoacetate (2.0 mL) was added at room temperature in portions, and the mixture was stirred for 4 hours. To the reaction mixture was added water, followed by extraction with ethyl acetate. This was washed with an aqueous saturated sodium chloride solution, dried with anhydrous sodium sulfate, and concentrated. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=1:3→0:1) to obtain the title compound (3.4 g) having the following physical property values. followed by extraction with ethyl acetate This was washed with an aqueous saturated sodium chloride solution dried with anhydrous sodium sulfate concentrated The residue was purified by silica gel column chromatography (hexane:ethyl acetate=1:3→0:1)

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

Procedure: To a 3 L florentine under nitrogen was charged Pd on C, wet, Degussa (10% Pd, 50% WATER) (8.120 g, 76.30 mmol) then EtOAc (1.706 L). The mixture was degassed via N2/vacuum cycles (3×), then a solution of O1-benzyl O4-tert-butyl piperidine-1,4-dicarboxylate 21 (243.7 g, 763.0 mmol) in EtOAc (243.7 mL) was added. Mixture was stirred under a hydrogen atmosphere overnight. Hydrogen was replenished and mixture was stirred for a further 3.5 h. Methanol (60 mL) was added to aid dissolution of precipitate then filtered through celite, washing through with methanol. Filtrate concentrated in vacuo to leave a brown oil with a slight suspension of a white solid, 138.6 g. Solid removed by filtration, and washed with minimal EtOAc. Filtrate was concentrated in vacuo to leave desired product as a light brown oil (129 g, 91%). 1H NMR (500 MHz, DMSO-d6) δ 2.88 (dt, 2H), 2.44 (td, 2H), 2.23 (tt, 1H), 1.69-1.64 (m, 2H) and 1.41-1.33 (m, 11H). The mixture was degassed via N2/vacuum cycles (3×) mixture was stirred for a further 3.5 h dissolution of precipitate then filtered through celite washing through with methanol Filtrate concentrated in vacuo to leave a brown oil with a slight suspension of a white solid, 138.6 g Solid removed by filtration washed with minimal EtOAc Filtrate was concentrated in vacuo

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 3 L flange flask equipped with a thermometer, condensor, nitrogen line and overhead stirrer was heated at 40° C. (external) then charged with cyclohexanol (750 mL), disodium carbonate (129.8 g, 1.225 mol), 3-bromo-4-chloro-5-fluoro-pyridine (Hydrochloric Acid 18) (137.5 g, 556.8 mmol) and tert-butyl piperidine-4-carboxylate (123.8 g, 668.2 mmol) rinsed in with cyclohexanol (350 mL). Mixture was heated to 120° C. internal temperature overnight (18 h). Reaction mixture was removed from hotplate and allowed to cool to room temperature. Water (687.5 mL) and EtOAc (687.5 mL) were added, stirred for 10 mins then transferred to separating funnel Additional EtOAc (1.238 L) was added, mixed and aqueous phase was removed. Organic phase was further washed with water (687 mL), aqueous phase removed, organic layer collected. Aqueous phases were combined and back extracted with EtOAc (687.5 mL), aqueous layer removed and organic phase combined with other organics. Organics concentrated in vacuo (water bath temp=60° C., vacuum down to 2 mBar) leaving a viscous brown oil. A 3 L flange flask equipped with a thermometer, condensor, nitrogen line and overhead stirrer rinsed in with cyclohexanol (350 mL) Mixture was heated to 120° C. internal temperature overnight (18 h) Reaction mixture was removed from hotplate to cool to room temperature Water (687.5 mL) and EtOAc (687.5 mL) were added to separating funnel Additional EtOAc (1.238 L) was added mixed aqueous phase was removed Organic phase was further washed with water (687 mL), aqueous phase removed organic layer collected back extracted with EtOAc (687.5 mL), aqueous layer removed Organics concentrated in vacuo (water bath temp=60° C., vacuum down to 2 mBar) leaving a viscous brown oil

Conditions: temp:170.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1-Chloro-4-(3-chloro-4-methoxybenzyl)amino-6-cyanophthalazine (2 g) prepared in Example 1 and t-butyl isonipecotate (2 g) were dissolved in 20 ml of N-methyl-2-pyrrolidone. The obtained solution was heated at 170° C. for 5 hours and cooled, followed by the addition of water. The obtained mixture was extracted with ethyl acetate. The organic phase was washed with water, dried over anhydrous magnesium sulfate and concentrated in a vacuum. The obtained residue was subjected to silica gel column chromatography and eluted with toluene/tetrahydrofuran (10:1) to give 1.6 g of 1-(4-tert-butoxycarbonyl-piperidino)-4-(3-chloro-4-methoxybenzyl)amino-6-cyanophthalazine. cooled The obtained mixture was extracted with ethyl acetate The organic phase was washed with water dried over anhydrous magnesium sulfate concentrated in a vacuum eluted with toluene/tetrahydrofuran (10:1)

Conditions: temp:170.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1-Chloro-4-(3-chloro-4-methoxybenzyl)amino-6-cyanophthalazine (2 g) prepared in Example 1 and t-butyl isonipecotate (2 g) were dissolved in 20 ml of N-methyl-2-pyrrolidone. The obtained solution was heated at 170° C. for 5 hours and cooled, followed by the addition of water. The obtained mixture was extracted with ethyl acetate. The organic phase was washed with water, dried over anhydrous magnesium sulfate and concentrated in a vacuum. The obtained residue was subjected to silica gel column chromatography and eluted with toluene/tetrahydrofuran (10:1) to give 1.6 g of 1-(4-tert-butoxycarbonyl-piperidino)-4-(3-chloro-4-methoxybenzyl)amino-6-cyanophthalazine. cooled The obtained mixture was extracted with ethyl acetate The organic phase was washed with water dried over anhydrous magnesium sulfate concentrated in a vacuum eluted with toluene/tetrahydrofuran (10:1)