Potassium Chloride → HCID 178510672, compound

Participants

Reaction Conditions

Reaction Steps

A 500 ml jacketed reactor with stirrer, baffles and condenser was initially charged under a nitrogen atmosphere with 103 g of ethylbenzene, 6.3 g of dimethylisopropylamine hydrochloride (0.050 mol, 99%) and 15.5 g of potassium chloride (0.208 mmol). Subsequently, 31.5 g of trifluoromethanesulfinic acid (0.223 mol, 95.0%), 17.9 g of dimethylisopropylamine (0.203 mol, 99%) and 24.2 g of thionyl chloride (203 mmol, 99.7%) were metered in at 0° C. with cooling. After subsequently adding 54.8 g of 5-amino-3-cyano-1-(2,6-dichlor-4-trifluoromethylphenyl)pyrazole, the reaction mixture was stirred at 0° C. for 1 h, then heated to 35° C. over 45 min and stirred at 35° C. for a further 10 h. After the reaction had been quenched with sodium hydroxide solution and extracted with ethyl acetate and ethylbenzene, a nonisolated yield of fipronil of 80% was obtained in the crude solution (determination by means of quantitative HPLC).

Provenance & Evidence