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

Participants

Reaction Conditions

Reaction Steps

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.

Provenance & Evidence