Hexachloroethane → 3-Chloro-N,N-dimethyl-1H-pyrazole-1-sulfonamide

Temperature

65 °C

To a solution of N-dimethylsulfamoylpyrazole (188.0 g, 1.07 mol) in dry tetrahydrofuran (1500 mL) at ˜78° C. was added dropwise a solution of 2.5 M n-butyllithium (472 mL, 1.18 mol) in hexane while maintaining the temperature below ˜65° C. Upon completion of the addition the reaction mixture was maintained at ˜78° C. for an additional 45 minutes, after which time a solution of hexachloroethane (279 g, 1.18 mol) in tetrahydrofuran (120 mL) was added dropwise. The reaction mixture was maintained for an hour at ˜78° C., warmed to ˜20° C. and then quenched with water (1 L). The reaction mixture was extracted with methylene chloride (4×500 mL); the organic extracts were dried over magnesium sulfate and concentrated. The crude product was further purified by chromatography on silica gel using methylene chloride as eluent to afford the title product compound as a yellow oil (160 g).

1. additionUpon completion of the addition the reaction mixture
2. temperaturewas maintained at ˜78° C. for an additional 45 minutes
3. temperatureThe reaction mixture was maintained for an hour at ˜78° C.
4. temperaturewarmed to ˜20° C.
5. customquenched with water (1 L)
6. extractionThe reaction mixture was extracted with methylene chloride (4×500 mL)
7. dry with materialthe organic extracts were dried over magnesium sulfate
8. concentrationconcentrated
9. customThe crude product was further purified by chromatography on silica gel

ORD record

ord-90df9732ba4544a0a49bfcb760a40507

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09173400B2