Dimethyl Sulfoxide → tert-butyl N-(4-oxocyclohexyl)carbamate

Temperature

-60 °C

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, 87%).

1. waitover a period of 35 minutes
2. stirringthe resulting mixture was stirred at −60° C. for 40 minutes
3. temperatureat −60° C., the resulting mixture was warmed up to room temperature spontaneously
4. extractionfollowed by extraction with chloroform
5. washThe organic layer was washed with a saturated aqueous ammonium chloride solution
6. dry with materiala saturated aqueous sodium chloride solution and then dried over magnesium sulfate
7. distillationThe solvent was distilled off under reduced pressure
8. customthe resulting residue was purified by a silica gel column chromatography (eluent: chloroform/ethyl acetate)

ORD record

ord-f83eba12dc1942659175f38355424e36

Source dataset

uspto-grants-2007_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07199147B2