Ethanol → HCID 86692432, compound

Temperature

100 °C

To a suspension of (5-bromo-3-chloropyridin-2-yl)hydrazine (14.78 g) in water (15 ml) and concentrated hydrochloric acid (15 ml), was added an ethanol solution (30 ml) of ethyl 2-(ethoxymethylene)acetoacetate (30 ml), prepared according to a method described in J. Chem. Soc. Perkin trans. I, 1875 (1988), and the mixture was stirred at 100° C. for 1.5 hours. The reaction solution was cooled to room temperature, water (100 ml) was added and extracted with ethyl acetate three times. The organic layer was dried over anhydrous sodium sulfate and concentrated in vacuo. n-Hexane (150 ml) was added, and ethyl acetate was further added little by little at 80° C. to completely dissolve the residue. The solution was cooled to room temperature and the precipitated solid was filtered. The filtrate was concentrated and a similar handling was repeated four times to give 1-(5-bromo-3-chloropyridin-2-yl)-5-methyl-1H-pyrazole-4-carboxylic acid ethyl ester (15.93 g) as a pale yellow solid.

1. customprepared
2. temperatureThe reaction solution was cooled to room temperature
3. extractionextracted with ethyl acetate three times
4. dry with materialThe organic layer was dried over anhydrous sodium sulfate
5. concentrationconcentrated in vacuo
6. additionn-Hexane (150 ml) was added
7. additionethyl acetate was further added little by little at 80° C.
8. dissolutionto completely dissolve the residue
9. temperatureThe solution was cooled to room temperature
10. filtrationthe precipitated solid was filtered
11. concentrationThe filtrate was concentrated

ORD record

ord-7186af7084f745a9a0c717c7b7f8dbcd

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09150555B2