Stannous Chloride → 3-Hydrazinyl-4-methylpyridine

2.55 ml of a 2.5 M aqueous sodium nitrite solution are added to a solution of 4.0 g (37 mmol) of 3-amino-4-methylpyridine in 19 ml of 6 N hydrochloric acid while cooling in an ice/salt bath. The resulting diazonium salt solution is slowly added dropwise at −10° C. to −15° C. to a solution of 21 g (111 mmol) of tin(II) chloride in 26 ml of hydrochloric acid. The solution is left to stand in a refrigerator overnight in order to complete the reaction. The precipitated solid is filtered off with suction, suspended in 26 ml of water, made basic with concentrated sodium hydroxide solution and filtered. The filtrate is extracted ten times with 20 ml of dichloromethane each time, and the combined organic phases are dried over sodium sulphate and concentrated. Drying under high vacuum results in 1.45 g (31% of theory) of the desired product as a colourless oil.

1. temperaturewhile cooling in an ice/salt bath
2. waitThe solution is left
3. customto stand in a refrigerator overnight in order
4. customthe reaction
5. filtrationThe precipitated solid is filtered off with suction
6. filtrationfiltered
7. extractionThe filtrate is extracted ten times with 20 ml of dichloromethane each time
8. dry with materialthe combined organic phases are dried over sodium sulphate
9. concentrationconcentrated
10. customDrying under high vacuum

ORD record

ord-cc53ce1fed784f939f19259fd174ac94

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08822479B2