tert-Butyl 4-(3-bromopropyl)piperazine-1-carboxylate

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:0.00; pressure:0.00; stir:

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

Procedure: 4-(3-Bromo-propyl)-piperazine-1-carboxylic acid tert-butyl ester (172 mg) was added to a mixture of 6-(3-chloro-4-hydroxy-5-trifluoromethyl-phenyl)-1-methyl-1H-imidazo[4,5-c]pyridine-4-carbonitrile (165 mg) and potassium carbonate (130 mg) in acetonitrile (15 ml). The mixture was refluxed for 4 hours, then ethyl acetate (50 ml) and water (30 ml) were added and the organic layer was washed with brine, then dried over sodium sulfate, filtered and concentrated under reduced pressure to afford a crude product, 4-{3-[2-chloro-4-(4-cyano-1-methyl-1H-imidazo[4,5-c]pyridin-6-yl)-6-trifluoromethyl-phenoxy]-propyl}-piperazine-1-carboxylic acid tert-butyl ester. The mixture was refluxed for 4 hours the organic layer was washed with brine dried over sodium sulfate filtered concentrated under reduced pressure

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

Procedure: Under nitrogen atmosphere, a solution of triphenylphosphine (0.94 g) in THF (4 ml) was added slowly to a mixture of 4-(3-hydroxy-propyl)-piperazine-1-carboxylic acid tert-butyl ester (0.80 g) and tetrabromomethane (1.19 g) in THF (15 ml). The mixture was stirred at room temperature for 16 hours, then ethyl acetate (100 ml) and a saturated solution of sodium carbonate (30 ml) were added and the organic layer was washed with brine, then dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was chromatographed over silica gel (eluent: Cyclohexane/Ethyl acetate 8/2) to afford 4-(3-bromo-propyl)-piperazine-1-carboxylic acid tert-butyl ester (0.66 g). the organic layer was washed with brine dried over sodium sulfate filtered concentrated under reduced pressure The residue was chromatographed over silica gel (eluent: Cyclohexane/Ethyl acetate 8/2)

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

Procedure: Sodium azide (2.24 g, 34.2 mmol) is added to a stirred solution of 4-(3-bromo-propyl)-piperazine-1-carboxylic acid tert-butyl ester (4.80 g, 15.6 mmol) in anhydrous DMF (DMF) (40 mL). The resultant mixture is heated in an oil bath at 55° C. under nitrogen for 3 days. At ambient temperature, ethyl acetate (160 mL) and half-saturated aqueous sodium chloride (NaCl) (200 mL) are added to the mixture. The organic layer is separated, washed with half-saturated aqueous NaCl (200 mL), dried over magnesium sulfate, filtered, and concentrated to provide the title compound as a dark oil (3.88 g, 92% yield). The organic layer is separated washed with half-saturated aqueous NaCl (200 mL) dried over magnesium sulfate filtered concentrated

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

Procedure: 1,3-Dibromopropane (6.78 mL, 66.8 mmol) is added to a stirred solution of piperazine-1-carboxylic acid tert-butyl ester (4.15 g, 22.2 mmol) and diisopropylethylamine (7.73 mL, 44.4 mmol) in anhydrous 1,4-dioxane (40 mL). The resultant mixture is heated in an oil bath at 90° C. for 20 hours. At ambient temperature ethyl acetate (160 mL) and half-saturated aqueous sodium bicarbonate (NaHCO3) (120 mL) are added to the mixture. The organic layer is separated, dried over magnesium sulfate, filtered, and concentrated. The crude oil is subjected to chromatography on silica gel and eluted with 2 M NH3/MeOH in dichloromethane 0-3% to provide the title compound as a dark oil (4.80 g, 70% yield). The organic layer is separated dried over magnesium sulfate filtered concentrated eluted with 2 M NH3/MeOH in dichloromethane 0-3%