Synthesis, Insecticidal Activities, and Structure-Activity Relationship Studies of Novel Diamide Compounds Containing (Halogenated) Alkoxy Group

In order to discover new pesticide with novel structure, good activity and environmental friendliness, a series of new diamide compounds containing (halogenated) alkoxy group were designed and synthesized through introducing (halogenated) alkoxy group based on the structure of cyproflanilide. Their structures were confirmed by H-1 NMR, C-13 NMR and HRMS. The bioassay results showed that most of the compounds exhibit excellent insecticidal activity against Plutella xylostella. Such as N-(2-bromo-6-(difluoromethoxy)-4-(perfluoropropan-2-yl)phenyl)-3-(N-(cyclopropylmethyl)-4-fluorobenzamido)-2-fluorobenzamide (4a), N-(2-bromo-4-(perfluoropropan-2-yl)-6-(trifluoromethoxy)phenyl)-3-(N-(cyclopropylmethyl)4-fluorobenzamido)-2-fluorobenzamide (4b), N-(2-bromo-6-(difluoromethoxy)-4-(perfluoropropan-2-yl)phenyl)-3-(N-(cyclopropylmethyl)benzamido)-2-fluorobenzamide (4h), N-(2- bromo-6-(difluoromethoxy)-4-(perfluoropropan-2-yl)phenyl)-3-(4cyano-N-(cyclopropylmethyl)benzamido)-2-fluorobenzamide (4j)similar to N-(3-((2-bromo-6-(difluoromethoxy)-4-(perfluoropropan2-yl)phenyl)carbamoyl)-2-fluorophenyl)-N-( cyclopropylmethyl)isonicotinamide (4o), N-(3-((2-bromo-6-(difluoromethoxy)4-(perfluoropropan-2-yl)phenyl)carbamoyl)-2-fluorophenyl)-N-(cyclopropylmethyl)-2,4-difluorobenzamide (4q) and N-(3-((2bromo-6-( difluoromethoxy)-4-(perfluoropropan-2-yl)phenyl)carbamoyl)-2-fluorophenyl)-N-(cyclopropylmethyl)-2-fluoroiso-nicotinamide (4t) showed 100% mortality at 1 mg/L. Moreover, compound 4a not only has good insecticidal activities against Plutella xylostella and Chilo suppressalis close to cyproflanilide, but also shows better activities against Aphis craccivora and Tetranychus cinnabarinus than cyproflanilide, exhibiting a broader insecticidal spectrum. The field trials of compound 4a are ongoing.