Beta-Alanine → N-(6-Chloropyridazin-3-yl)-beta-alanine

To a solution of 3,6-dichloropyridazine (50.0 mmol, 7.45 g) and 3-aminopropionic acid (60.0 mmol, 5.34 g) in absolute ethanol (20 mL) was added potassium carbonate (30.0 mmol, 4.15 g), and the suspension was heated to reflux for 3 hours. The mixture was allowed to cool to room temperature, and the light brown solid residue was partitioned between ethyl acetate (300 mL) and water (300 mL). The pH of the aqueous phase was adjusted to 3.5 with 2M aqueous hydrochloric acid, and the yellow solid was filtered and washed with absolute ethanol (10 mL) and diethyl ether (2×20 mL) to give 5.04 g (50%). The product was pure according to TLC Rf 0.31 (dichloromethane/methanol/acetic acid, 85:10:5).

1. temperaturethe suspension was heated
2. temperatureto reflux for 3 hours
3. customthe light brown solid residue was partitioned between ethyl acetate (300 mL) and water (300 mL)
4. filtrationthe yellow solid was filtered
5. washwashed with absolute ethanol (10 mL) and diethyl ether (2×20 mL)
6. customto give 5.04 g (50%)

ORD record

ord-f33fd4f956ee42a9a6336303085bc0e2

Source dataset

uspto-grants-2003_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06617422B1