4-N-Boc-aminocyclohexanone

A methylene chloride solution (6 ml) of dimethyl sulfoxide (2.0 ml, 28.2 mmol) was added dropwise to a methylene chloride solution (30 ml) of oxalyl chloride (1.7 ml, 19.5 mmol) at -60°C over a period of 10 minutes and stirred at -60°C for another 10 minutes. Then, a methylene chloride solution (140 ml) of tert-butyl 4-hydroxycyclohexylcarbamate (2.56 g, 11.9 mmol) was added dropwise thereto over a period of 35 minutes, and the resulting mixture was stirred at -60°C for 40 minutes. After triethylamine (8.4 ml, 60.3 mmol) was added thereto at -60°C, the resulting mixture was warmed up to room temperature spontaneously. Water was added to the reaction mixture, followed by extraction with chloroform. The organic layer was washed with a saturated aqueous ammonium chloride solution and a saturated aqueous sodium chloride solution and then dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the resulting residue was purified by a silica gel column chromatography (eluent: chloroform/ethyl acetate) to obtain tert-butyl 4-oxocyclohexylcarbamate (2.23 g, 87percent).1H-NMR (DMSO-d6): 1.06-1.20 (4H, m), 1.35 (9H, s), 1.69-1.76 (4H, m), 3.12-3.31 (2H, m), 4.48 (1H, s), 6.64 (1H, d, J=7.5Hz).Step-2, Dess-Martin oxidizer (29.0 g, 68.3 mmol) was added dropwise to a solution of N-4-Boc-aminocyclohexanol (9.8 g, 45.52 mmol) in dichloromethane (200 mL) with ice-bath stirring. Warm to room temperature and stir the reaction mixture overnight. The mixture was carefully quenched with a saturated aqueous solution of sodium thiosulfate in an ice bath and extracted three times with dichloromethane. The combined organic phases were washed with brine, dried over sodium sulfate, filtered, and concentrated in vacuo. Column chromatography on a silica gel column yielded 4-oxo. Tert-butyl cyclohexylcarbamate (7.96 g, yield 82.1percent).To a solution of tert- v y 4-hydroxy- cyclohexylcarbamate (10.0 g, 46.5 mmol) in DCM (100 mL) was added Dess-Martin periodinane (39.4 g, 92.9 mmol) portionwise. The resulting solution was stirred at r.t. overnight and treated with aq. NaThe oxalyl chloride (11.8 mL, 0.14 mol) was dissolved in methylene chloride (100 mL) and then cooled to -78 ° C. Under nitrogen, To a solution of dimethylsulfoxide diluted in methylene chloride (100 mL) Im-1c-a (20 g, 0.093 mol) diluted in dichloromethane (19.8 mL, 0.28 mol) and methylene chloride (300 mL) were added dropwise. Methylene chloride (300 mL) was further added to the reaction mixture, and the mixture was stirred for 1 hour. Triethylamine (64.7 mL, 0.46 mol) was added dropwise and stirred for 1 hour. The reaction mixture was stirred for 2 hours while slowly raising the temperature to room temperature, and distilled water (100 mL) was added to terminate the reaction. The reaction mixture was extracted with methylene chloride. The organic layer was washed with distilled water and saturated brine, dried over anhydrous sodium sulfate, concentrated, and n-hexane was added to the residue to obtain a solid. The resulting solid was filtered and washed with n-hexane to give the title compound im-1c-b as a pale brown solid (20.5 g).

Molecular Weight:213.27
XLogP3:1.2
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:3
Exact Mass:213.13649347
Monoisotopic Mass:213.13649347
Topological Polar Surface Area:55.4
Heavy Atom Count:15
Complexity:245
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes