反应详情

A substantial molar excess of trimethylorthoformat is reacted with fipronil (Compound IV) at reflux with 0.5 equivalents of paratoluensulfonic acid to provide 3-Cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-5-methoxymethylideneamino-4-trifluoromethylsulfinylpyrazole (Compound III).