Sodium Thiosulfate → tert-butyl N-(2-methyl-1-oxopropan-2-yl)carbamate

0.94 g of tetramethylpiperidine N-oxide (6.0 mmol) and 3.57 g of potassium bromide (30 mmol) were added to a solution of 56.78 g of (2-hydroxy-1,1-dimethylethyl)carbamic acid t-butyl ester obtained in Reference Example (3a) (300 mmol) in a mixture of methylene chloride (500 ml) and a saturated sodium bicarbonate aqueous solution (525 ml) under ice-cooling, and the mixture was stirred at the same temperature for 30 minutes. 534 ml of a 5% sodium hypochlorite aqueous solution (360 mmol) was added to the reaction mixture under ice-cooling over 1.5 hours, and the mixture was stirred at the same temperature for 20 minutes. A saturated sodium thiosulfate aqueous solution was added to the reaction mixture, and the reaction mixture was returned to room temperature, followed by extraction with methylene chloride. Then, the organic layer was washed with brine and then dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure. Hexane was added to the residue, and the solid was collected by filtration to obtain 42.32 g of the title compound (yield: 79%).

1. temperaturecooling over 1.5 hours
2. stirringthe mixture was stirred at the same temperature for 20 minutes
3. customwas returned to room temperature
4. extractionfollowed by extraction with methylene chloride
5. washThen, the organic layer was washed with brine
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationAfter filtration
8. customthe solvent was evaporated under reduced pressure
9. additionHexane was added to the residue
10. filtrationthe solid was collected by filtration

ORD record

ord-91737fc94f78459f87c691979b38dfd4

Source dataset

uspto-grants-2012_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08158790B2