Synthesis of Fluorinated Pyrethroids : Conversion of Pyrethroid Metabolites into Some Insecticidal Fluorinated Derivatives

Abstract

New fluorinated pyrethroids were designed to block microsomal oxidation at the C-10 methyl group of biophenothrin and at the C-7' methylene of bioallethrin. By using diethylaminosulfur trifluoride and/or hexafluoropropene diethylamine, 10, 10-difluorobiophenothrin and 7'-fluorobioallethrin were synthesized from the oxidized derivatives of the parent insecticides, which have been recognized as microsomal metabolites. While 10-hydroxybiophenothrin was not successfully converted into the corresponding 10-fluoro derivative by either fluorination reagent, other monofluorinated compounds were formed and their structures were elucidated.