The discovery of pyridalyl: a novel insecticidal agent for controlling lepidopterous pests.

Synthesis of analogues of two compounds with known insecticidal activity, both of which contain a 3,3-dichloro-2-propenyloxy group, produced 2-(trifluoromethyl)-4-phenoxyphenyl 3,3-dichloro-2-propenyl ether, which had weak activity against lepidopterous larvae. Structural modifications around this lead compound led to the development of pyridalyl [Pleo, S-1812; 2,6-dichloro-4-(3,3-dichloroallyloxy)phenyl 3-[5-(trifluoromethyl)-2-pyridyloxy]propyl ether], which belongs to a new class of insecticides. Pyridalyl gives very good control of various lepidopterous and thysanopterous pests on cotton and vegetables, without phytotoxicity.