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

Temperatur

-78 °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-butyl-lithium (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 160 g of the title product compound as a yellow oil.

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

ORD-Eintrag

ord-4d225556b52143f1aef1b4ffe52d0c75

Quelldatensatz

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08475819B2