Synthesis of new bicyclo[4.1.0]heptane-2,4-dione derivatives and their herbicidal activity

摘要

Various triketone type 4-HPPD inhibitors were synthesized and their herbicidal activity and corn safety were evaluated.In the course of synthetic studies,we invented convenient methods to synthesize novel benzoyl-substi-tuted bicyclo[4.1.0]heptanediones,and it was found that some showed excellent herbicidal activity against weeds in a corn field.Among these compounds,3-(4-chloro-2-nitrobenzoyl)bicyclo[4.1.0]heptane-2,4-dione was found to be not only highly active against broadleaf weeds but also grass weeds,whereas it caused severe damage to corn.As a result of further efforts to modify benzoyl substituents,we found a compound,(1R*,6R*)-3-(2-chloro-4-methylsulfonylbenzoyl)bicyclo[4.1.0]heptane-2,4-dione,which provided a good combination of herbicidal activity and corn safety.