Hydrazine hydrate (1:1) → Pyrazine-2-Carboxylic Acid Hydrazide

Methyl 2-pyrazinecarboxylate (I132) (42 g, 304 mmol) was dissolved in ethanol (750 mL) and treated with hydrazine hydrate (22.17 mL, 456 mmol). The solution was stirred at room temperature for 5 minutes whereupon a precipitate started to form. The mixture was cautiously heated to 80° C. for 5 h and cooled to room temperature. Approximately 50% of the solvent was then removed in vacuo, the slurry was heated to reflux and the solution cooled to room temperature overnight. The resulting solid was filtered, washed with a little ethanol, diethyl ether and dried in a vacuum oven to afford product in 39.77 g as beige needles.

1. customto form
2. temperatureThe mixture was cautiously heated to 80° C. for 5 h
3. temperaturecooled to room temperature
4. customApproximately 50% of the solvent was then removed in vacuo
5. temperaturethe slurry was heated
6. temperatureto reflux
7. temperaturethe solution cooled to room temperature overnight
8. filtrationThe resulting solid was filtered
9. washwashed with a little ethanol, diethyl ether
10. customdried in a vacuum oven
11. customto afford product in 39.77 g as beige needles

ORD record

ord-0dadb86913c441cb9e2b646600be05e3

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08501946B2