Sodium Hydroxide → 2-Chloro-3-hydrazinylpyridine

Temperature

0 °C

A solution of 3-amino-2-chloropyridine (5 g, 38.9 mmol) in concentrated hydrochloric acid (50 ml) was cooled to −5° C. and a solution of sodium nitrite (2.7 g, 38.9 mmol) in water (25 ml) was added thereto. The reaction mixture was stirred for 15 minutes at 0° C. and a solution of tin(II) chloride dihydrate (17.6 g, 77.8 mmol) in concentrated hydrochloric acid (17.5 ml) was slowly added thereto. The reaction mixture was stirred for 1 hour at room temperature, basified with 2N sodium hydroxide solution, and then extracted with dichloromethane. The organic layer was dried on anhydrous magnesium sulfate, filtered, and then concentrated under reduced pressure. The resulting residue was crystallized with ethyl ether to give 2 g of the titled compound as a pale yellow solid. (Yield: 36%).

1. stirringThe reaction mixture was stirred for 1 hour at room temperature
2. extractionextracted with dichloromethane
3. dry with materialThe organic layer was dried on anhydrous magnesium sulfate
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customThe resulting residue was crystallized with ethyl ether

ORD record

ord-0273b21b3f3e4700a784000cf03f23c4

Source dataset

uspto-grants-2010_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07662832B2