1-Chloroethyl chloroformate → 1-Methanesulfonylpiperazine hydrochloride

To dichloromethane (70 ml) was added the compound (9.58 g, 37.66 mmol) obtained in step A and 1-chloroethyl chloroformate (4.53 ml, 41.43 mmol) was added under ice-cooling with stirring, and the mixture was stirred at room temperature for 1 hr. The reaction mixture was concentrated under reduced pressure, the residue was dissolved in methanol (70 ml), and the mixture was heated under reflux for 30 min. The reaction mixture was cooled to room temperature, and the precipitated solid was filtered and washed with a small amount of methanol. The filtrate was concentrated under reduced pressure, and the precipitated solid was filtered, and washed with a small amount of methanol. The obtained solid was combined, and the mixture was washed with diethyl ether to give the title compound (6.65 g, yield 88%) as a colorless solid.

1. additionwas added under ice-
2. temperaturecooling
3. stirringthe mixture was stirred at room temperature for 1 hr
4. concentrationThe reaction mixture was concentrated under reduced pressure
5. dissolutionthe residue was dissolved in methanol (70 ml)
6. temperaturethe mixture was heated
7. temperatureunder reflux for 30 min
8. filtrationthe precipitated solid was filtered
9. washwashed with a small amount of methanol
10. concentrationThe filtrate was concentrated under reduced pressure
11. filtrationthe precipitated solid was filtered
12. washwashed with a small amount of methanol
13. washthe mixture was washed with diethyl ether

ORD record

ord-48ff15caf9174bb5ab2701686ba7e926

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08513235B2