Malononitrile → 2-Methoxy-6-oxo-4-(trifluoromethyl)-1,4,5,6-tetrahydropyridine-3-carbonitrile

With ice cooling, 7.47 g (138.39 mmol) of sodium methoxide in methanol (85 ml) were initially charged, and 6.04 g (91.44 mmol) of malononitrile were added. With stirring, 11.84 g (76.84 mmol) of methyl 4,4,4-trifluorocrotonate were then added dropwise, and the mixture was stirred at RT for 30 min and then heated at reflux for 1 h. Under reduced pressure, the mixture was then concentrated to dryness. Water was added to the residue, and the mixture was extracted four times with ethyl acetate. The combined organic phases were dried with sodium sulphate, filtered and concentrated. Further purification was carried out by chromatography on silica gel (cyclohexane/ethyl acetate 3:1). This gave 1.95 g of the title compound (11% of theory).

1. stirringthe mixture was stirred at RT for 30 min
2. temperatureheated
3. temperatureat reflux for 1 h
4. concentrationUnder reduced pressure, the mixture was then concentrated to dryness
5. additionWater was added to the residue
6. extractionthe mixture was extracted four times with ethyl acetate
7. dry with materialThe combined organic phases were dried with sodium sulphate
8. filtrationfiltered
9. concentrationconcentrated
10. customFurther purification

ORD record

ord-caa06dc6899246368aa1946828b8fd9a

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09216978B2