Synthesis and insecticidal activity of lipophilic amides. Part 7. Alternative aromatic groups for phenyl in 6‐phenylhexa‐2,4‐dienamides

Synthesis of a wide range of analogues of the lead compound, N‐2‐methylpropyl‐6‐phenylhexa‐2,4‐dienamide, in which phenyl was replaced by other aromatic systems is reported. In cases where rearrangement rendered the N‐2‐methylpropyl compound less accessible, N‐2,2‐dimethylpropyl substitution was used, because rearrangement was then suppressed. Several of the groups examined, for instance 2‐naphthyl, enhanced insecticidal activity, and when appropriately substituted, particularly with halogen, led to the most active compounds discovered in this series.