Iodoethane → 4,5-dichloro-2-ethyl-3(2H)-pyridazinone

Temperature

55 °C

To a suspension of 4.00 g (24.2 mmol) of 4,5-dichloro-2H-pyridazin-3-one (CAS: [932-22-9]) and 6.70 g (48.5 mmol) of potassium carbonate in 40 ml of acetone were added 3.92 ml (7.56 g, 48.5 mmol, 2 eq.) of ethyl iodide. The suspension was stirred for 8 h at 55° C. and allowed to cool to room temperature. The reaction was filtered and the solids were washed twice with acetone. The filtrate was concentrated in vaccuo, taken up in ethyl acetate and the precipitated salts were filtered off. The filtrate was concentrated in vaccuo, taken up in methylene chloride and purified by flash chromatography (SiO2, heptane:ethyl acetate 80:20 v/v) to yield the title compound as a light yellow crystalline solid.

1. temperatureto cool to room temperature
2. filtrationThe reaction was filtered
3. washthe solids were washed twice with acetone
4. concentrationThe filtrate was concentrated in vaccuo
5. filtrationthe precipitated salts were filtered off
6. concentrationThe filtrate was concentrated in vaccuo
7. custompurified by flash chromatography (SiO2, heptane:ethyl acetate 80:20 v/v)

ORD record

ord-7bae2997fb574a268dd25a4f08dbe2a1

Source dataset

uspto-grants-2012_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08334287B2