Dimethyl Sulfoxide → tert-butyl N-methyl-N-(3-oxopropyl)carbamate

Temperature

-78 °C

Dimethylsulfoxide (6.22 ml, 87.6 mmol) was dissolved in dry dichloromethane (100 ml) under nitrogen and the solution was cooled to −78° C. with stirring. Oxalyl chloride (3.95 ml, 45.4 mmol) was then added dropwise and the solution was stirred at −78° C. for a further 30 minutes when effervescence had ceased. A solution of (3-hydroxypropyl)methylcarbamic acid, 1,1-dimethylethyl ester (6.62 g, 35.0 mmol) in dichloromethane (100 ml) was then added dropwise at −78° C. The resultant solution was stirred at −78° C. for 45 minutes, then a solution of triethylamine (24.4 ml, 175 mmol) in dichloromethane (50 ml) was added. The resultant solution was allowed to warm to room temperature and stirred for a further 18 h. The reaction mixture was then poured into brine and extracted with dichloromethane three times. The combined organic fractions were then washed with brine and dried over magnesium sulfate. The solvent was evaporated and the residue triturated with diethyl ether and filtered. The solvent was evaporated to give the title compound (6.60 g, 100%) as an orange oil.

1. stirringthe solution was stirred at −78° C. for a further 30 minutes when effervescence
2. temperatureto warm to room temperature
3. stirringstirred for a further 18 h
4. extractionextracted with dichloromethane three times
5. washThe combined organic fractions were then washed with brine
6. dry with materialdried over magnesium sulfate
7. customThe solvent was evaporated
8. customthe residue triturated with diethyl ether
9. filtrationfiltered
10. customThe solvent was evaporated

ORD record

ord-095a1bd7d4e24a46b9c6ba2f14655a29

Source dataset

uspto-grants-2005_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06900243B2