The pyrethrins and related compounds. Part XLII: Structure-activity relationships in fluoro-olefin non-ester pyrethroids

A series of compounds containing fluorine atoms in place of hydrogen in olefinic non-ester pyrethroids has been synthesised using a route based on novel intermediates, ie 2-fluoroallyl acetates, which are coupled with aryl Grignard reagents, and tested against several insect species. In most cases, after introduction of fluorine at the olefinic position, the activity remains high in both the 1-aryl-1-(3-arylprop-2-enyl) cyclopropane and the (1-aryl-4-arylbut-2-enyl) cyclopropane series. In particular, the former series have potential as soil insecticides, because in tests against Diabrotica balteata, activities were high, and dose-transferability factors were increased by the introduction of fluorine. (C) 1999 Society of Chemical Industry.