tert-butyl 4-oxoazepane-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:

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

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

Procedure: Thiazole (21.3 g, 250 mmol) in THF (160 mL) was cooled to −70° C. and then n-BuLi (100 mL, 250 mmol) was added slowly over 5 minutes, keeping the temperature at −60° C. or lower. The resulting slurry was stirred for 45 minutes at this temperature and then the product of Step 1 (48.55 g, 228 mmol) in THF (50 mL) was added dropwise, maintaining the temperature at −60° C. The solution was stirred for one hour and then the cooling bath removed. At −20° C., 2M HCl (114 mL) was added and upon warming to RT the homogeneous solution was diluted with EtOAc (150 mL). The phases were separated and the aqueous layer was extracted with EtOAc (150 mL). The combined organic layers were washed with aqueous saturated NaHCO3 (150 mL), brine (150 mL) and then concentrated to a thick syrup. This was dissolved in EtOAc (140 mL) and then treated with hexane (210 mL) and the slurry filtered to afford tert-butyl 4-hydroxy-4-(1,3-thiazol-2-yl)azepane-1-carboxylate as a white solid (68.0 g, 220 mmol) and the material was then subjected to chiral chromatography to afford tert-butyl (4R)-4-hydroxy-4-(1,3-thiazol-2-yl)azepane-1-carboxylate (14.5 g, 48.6 mmol). at −60° C. The solution was stirred for one hour the cooling bath removed At −20° C., 2M HCl (114 mL) was added upon warming to RT the homogeneous solution was diluted with EtOAc (150 mL) The phases were separated the aqueous layer was extracted with EtOAc (150 mL) The combined organic layers were washed with aqueous saturated NaHCO3 (150 mL), brine (150 mL) concentrated to a thick syrup This was dissolved in EtOAc (140 mL) treated with hexane (210 mL) the slurry filtered

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

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

Procedure: To a cold (0° C.) stirred solution of 1-t-butoxycarbonyl-4-oxohomopiperidine (1.42 g, 6.07 mmol) in anhydrous THF (50 mL) under argon was added dropwise 1.0 M 4-chlorophenylmagnesium bromide in diethyl ether (10 mL, 10 mmol). The reaction was warmed to RT for 2 hrs then quenched with sat'd aqueous NH4Cl (5 mL). The reaction mixture was extracted with EtOAc (2×50 mL), the organic layers combined and dried over Na2SO4. Pure 1-t-butoxycarbonyl-4-(4-chlorophenyl)-4-hydroxyhomopiperidine (2.1 g, 96%) was isolated via silica gel flash chromatography eluting with 50% EtOAc/hexane. 1H NMR CDCl3 δ 1.43 (9H, s), 1.61-2.22 (6H, m), 3.21-3031 (2H, m), 3.48-3.82 (2H, m). then quenched with sat'd aqueous NH4Cl (5 mL) The reaction mixture was extracted with EtOAc (2×50 mL) dried over Na2SO4

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

Procedure: To a cold (0° C.) stirred solution of 1-t-butoxycarbonyl-4-oxohomopiperidine (1.42 g, 6.07 mmol) in anhydrous THF (50 mL) under argon was added dropwise 1.0 M 4-chlorophenylmagnesium bromide in diethyl ether (10 mL, 10 mmol). The reaction was warmed to RT for 2 hrs then quenched with sat'd aqueous NH4Cl (5 mL). The reaction mixture was extracted with EtOAc (2×50 mL), the organic layers combined and dried over Na2SO4. Pure 1-t-butoxycarbonyl-4-(4-chlorophenyl)-4-hydroxyhomopiperidine (2.1 g, 96%) was isolated via silica gel flash chromatography eluting with 50% EtOAc/hexane. 1H NMR CDCl3 δ 1.43 (9H, s), 1.61-2.22 (6H, m), 3.21-3031 (2H, m), 3.48-3.82 (2H, m). then quenched with sat'd aqueous NH4Cl (5 mL) The reaction mixture was extracted with EtOAc (2×50 mL) dried over Na2SO4

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

Procedure: To a stirred solution of 4-oxohomopiperidine.HCl (1.2 g, 8.05 mmol), NaOH (0.68 g, 16.9 mmol) in t-BuOH/H2O (1:1, 10 mL) was added t-butyldicarbonate (1.93 mL, 8.9 mmol) drop-wise. The reaction was stirred at RT overnight, extracted with EtOAc (2×10 mL) and the organic layer separated. The organic layer was dried over Na2SO4 and concentrated under vacuo. Pure 1-t-butoxycarbonyl-4-oxohomopiperidine (1.42 g, 84%) was isolated via silica gel flash chromatography eluting with 50% EtOAc/hexane. extracted with EtOAc (2×10 mL) the organic layer separated The organic layer was dried over Na2SO4 concentrated under vacuo