Stannous chloride dihydrate → 5-Hydrazinyl-2-methoxypyridine

A solution of 5-amino-2-methoxy pyridine (1.0 g, 8.0 mmol) in 37% hydrochloric acid (7 mL) was cooled in an ice-salt bath and a solution of sodium nitrite (611 mg, 8.8 mmol) in water (2 mL) was added dropwise. The reaction mixture was stirred for 15 minutes then slowly added to an ice-cold solution of tin(II)chloride dihydrate (5.5 g, 24 mmol) in 37% hydrochloric acid (7 mL). After 3 hours at 0° C. the solids were collected by filtration and dissolved in 5% sodium hydroxide solution. The acidic, aqueous filtrate was carefully neutralized with 12M sodium hydroxide, then more base was added to raise the pH to about 12. The alkaline solutions were combined and extracted several times with ether. The extract was dried over sodium sulfate, filtered and concentrated to afford 5-hydrazino-2-methoxypyridine, and was used without further purification.

1. filtrationAfter 3 hours at 0° C. the solids were collected by filtration
2. dissolutiondissolved in 5% sodium hydroxide solution
3. additionmore base was added
4. temperatureto raise the pH to about 12
5. extractionextracted several times with ether
6. dry with materialThe extract was dried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated

ORD record

ord-fd504a623b6c46e9995a91cf5e14e5b2

Source dataset

uspto-grants-1994_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05367077