Hydrazine hydrate (1:1) → 3-Methylpyridine-2-carbohydrazide

Ethyl 3-methylpyridine-2-carboxylate (2 g, 12.11 mmol, CAS [58997-10-7], commercially available e.g. from Beta Pharma) was dissolved in ethanol (40 mL) and treated with hydrazine monohydrate (0.706 mL, 14.53 mmol). The reaction mixture was stirred at room temperature for 15 mins before heating at reflux for 18 hours. The reaction mixture was cooled to room temperature, more hydrazine monohydrate (0.5 ml) was added, and the reaction mixture was heated at reflux for a further 24 hours. The reaction mixture was cooled to room temperature. The solvent was evaporated to near dryness, and the residue was azeotroped with ethanol (3×35 ml). The mixture was evaporated to dryness after the third time to afford a pale yellow solid. This solid was slurried in diethyl ether, filtered off and dried to afford the title compound as a white solid (0.575 g, 3.80 mmol).

1. temperaturebefore heating
2. temperatureat reflux for 18 hours
3. temperatureThe reaction mixture was cooled to room temperature
4. temperaturethe reaction mixture was heated
5. temperatureat reflux for a further 24 hours
6. temperatureThe reaction mixture was cooled to room temperature
7. customThe solvent was evaporated
8. customthe residue was azeotroped with ethanol (3×35 ml)
9. customThe mixture was evaporated to dryness after the third time
10. customto afford a pale yellow solid
11. filtrationfiltered off
12. customdried

ORD record

ord-5ba34fcd7f5342348a472c52a8933dbd

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08501946B2