Hydrochloric Acid → 4-ethenyl-1,5-dimethyl-3-(trifluoromethyl)-1H-pyrazole

Temperature

130 °C

10.0 g (41.2 mmol) of 4-bromo-1,5-dimethyl-3-(trifluoromethyl)-1H-pyrazole, 92.4 mg (0.41 mmol) of palladium acetate and 302 mg (0.82 mmol) of tetra-n-butylammonium bromide are weighed into the glass insert of an autoclave together with 366 mg (1.65 mmol) of di(tert-butyl)phenylphosphine, 8.84 g (45.3 mmol) of dicyclohexylmethylamine and dimethylacetamide (34.3 ml), and placed under a protective gas atmosphere. Subsequently, 30 bar of ethylene are injected at 20° C. and the reaction mixture is stirred at 130° C. for 30 h. After the end of the reaction, the mixture is cooled, poured onto cold dilute hydrochloric acid and extracted with CH2C12. The combined organic phases which have been dried over magnesium sulphate are concentrated. The product is obtained as a brown oil in an 83% yield.

1. customare injected at 20° C.
2. customAfter the end of the reaction
3. temperaturethe mixture is cooled
4. extractionextracted with CH2C12
5. dry with materialThe combined organic phases which have been dried over magnesium sulphate
6. concentrationare concentrated
7. customThe product is obtained as a brown oil in an 83% yield

ORD record

ord-c8276a13236144cc8ad83cac4d23efab

Source dataset

uspto-grants-2005_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06916839B2