Synthesis of Stenusine, the Spreading Agent of the Beetle Stenus comma

Article abstract of DOI:10.1021/jo00053a025

Stenusine, <1-ethyl-3-(2-methylbutyl)piperidine>, the spreading agent of Stenus comma, was synthesized by a six-step sequence in 21 percent overall yield from acetaldehyde.Acetaldehyde was converted into the corresponding N-tert-butyl aldimine, which was sequentially alkylated via its 1-azaallylic anion with 1-bromo-2-methylbutane and 1-bromo-3-chloropropane.The resulting δ-chloro-aldimine was hydrolyzed into the δ-chloro aldehyde, which was converted into the corresponding N-ethyl-aldimine.The latter labile δ-chloro aldimine was cyclized with lithium aluminum hydride to afford stenusine.The 1-tert-butyl analogue of stenusine was synthesized using an analogous route.