Triethylamine → n-Hydroxypyrimidine-5-carboximidamide

Temperature

0 °C

5-Cyanopyrimidine (J. Org. Chem. 1962, 27, 2264) (0.64 g, 6.1 mmol) was dissolved in methanol (20 mL), the solution was cooled to 0° C. then hydroxylamine hydrochloride (0.42 g, 6.1 mmol) and triethylamine (0.84 mL, 6.1 mmol) were added and the mixture was heated to reflux overnight. The mixture was cooled to room temperature, and the solvent was removed in vacuo. The residue was pre-absorbed onto silica gel, and purified by flash chromatography on silica gel (dichloromethane/methanol/aqueous ammonia—95:5:0.5 as eluant) to give a yellow solid which was contaminated with triethylamine hydrochloride. Recrystallisation from ethanol gave the title compound as a white solid (0.44 g).

1. temperaturethe mixture was heated
2. temperatureto reflux overnight
3. temperatureThe mixture was cooled to room temperature
4. customthe solvent was removed in vacuo
5. customThe residue was pre-absorbed onto silica gel
6. custompurified by flash chromatography on silica gel (dichloromethane/methanol/aqueous ammonia—95:5:0.5 as eluant)
7. customto give a yellow solid which
8. customRecrystallisation from ethanol

ORD record

ord-a93ff3a5d7bf4bb0a869ab4bbd72fe5b

Source dataset

uspto-grants-2004_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06821972B2