Hydrazine hydrate (1:1) → 4-Chloro-6-hydrazinylpyrimidine

At RT, 11.8 ml (12.1 g, 241.6 mmol) of hydrazine hydrate are added dropwise with stirring to a solution of 20.0 g (134.3 mmol) of 4,6-dichloropyrimidine in 300 ml of ethanol. If the solution becomes turbid during the metered addition of the hydrazine hydrate, further ethanol (about 400 ml) is added. The reaction solution is stirred at RT for 12 h. For work-up, the precipitated solid is filtered off, the filter residue is washed twice with in each case 150 ml of water and twice with in each case 100 ml of diethyl ether and the product is dried under reduced pressure. The concentrated mother liquor gives a further crystalline product fraction. Yield: 16.8 g (87% of theory)

1. additionis added
2. filtrationFor work-up, the precipitated solid is filtered off
3. washthe filter residue is washed twice with in each case 150 ml of water and twice with in each case 100 ml of diethyl ether
4. customthe product is dried under reduced pressure
5. customThe concentrated mother liquor gives a further crystalline product fraction

ORD record

ord-a90f3ccb598144bb9f630c2e5eeabdc2

Source dataset

uspto-grants-2011_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08067407B2