2-Amino-5-methylpyridine → 2-aMino-5-Methylpyridine-3-sulfonyl chloride

Temperature

140 °C

Solid 2-amino-5-picoline (10.8 g, 0.10 mol) was added portionwise to chlorosulfonic acid (66 mL, 1.0 mol) at ambient temperature over 5 minutes. When the addition was complete, the mixture was warmed to 140° C. and stirred at that temperature for 2 hours. During the heating period gas evolution was initially rapid and ceased completely after 2 hours. The mixture was then cooled to room temperature and poured onto 2 liters of ice. Solid sodium bicarbonate was added to the resulting solution to adjust the pH to about 7.0. The solid product that precipitated was collected and rinsed with a small amount of cold ethanol. The solid was then dissolved in one liter of hot chloroform, the resulting solution was dried (magnesium sulfate), and the solution was concentrated to a volume of about 100 mL. The solid product that formed was collected, the mother liquor was concentrated to 20 mL and a second crop was collected. The solid products were combined to give the title compound (14.4 g, 70 %); m.p. 16°-166° C.

1. additionWhen the addition
2. waitceased completely after 2 hours
3. temperatureThe mixture was then cooled to room temperature
4. customThe solid product that precipitated
5. customwas collected
6. washrinsed with a small amount of cold ethanol
7. dissolutionThe solid was then dissolved in one liter of hot chloroform
8. dry with materialthe resulting solution was dried (magnesium sulfate)
9. concentrationthe solution was concentrated to a volume of about 100 mL
10. customThe solid product that formed
11. customwas collected
12. concentrationthe mother liquor was concentrated to 20 mL
13. customa second crop was collected

ORD record

ord-5eeb73fc862140c9846a967262927b7c

Source dataset

uspto-grants-1995_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05378704