Hydrochloric Acid → 6-Chloro-5-methylpyridine-3-sulfonyl chloride

Under ice-cooling, thionyl chloride (0.6 mL) was added dropwise over 30 min to water (3.4 mL). The mixture was stirred at room temperature for 12 hr to give a sulfur dioxide-containing solution. Separately, under ice-cooling, 6-chloro-5-methylpyridine-3-amine (278 mg) was added to concentrated hydrochloric acid (6 mL) and the mixture was stirred. An aqueous solution (2 mL) of sodium nitrite (148 mg) was added dropwise while keeping the inside temperature at not higher than 5° C., and the mixture was further stirred for 15 min. The reaction mixture was gradually added at 5° C. to the above-mentioned sulfur dioxide-containing solution added with cuprous chloride (5 mg). Under ice-cooling, the mixture was further stirred for 30 min, and the precipitate was collected by filtration and washed with water to give the title compound as a pale-yellow solid (yield 271 mg, 62%).

1. additioncontaining solution
2. temperatureSeparately, under ice-cooling
3. customhigher than 5° C.
4. stirringthe mixture was further stirred for 15 min
5. additioncontaining solution
6. temperatureUnder ice-cooling
7. stirringthe mixture was further stirred for 30 min
8. filtrationthe precipitate was collected by filtration
9. washwashed with water

ORD record

ord-ac3d854fd6cf4978aa4a3c22e347c5ff

Source dataset

uspto-grants-2011_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07977488B2