New and practical synthesis of (Z)-8-dodecene-1-yl acetate and (E)-8-dodecene-1-yl acetate were developed. The synthesis were based on a C3+C6=C9 and C9+C3=C12 coupling scheme, the starting material being 2-propyn-1-ol and 1,6-hexandiol. The routes involve, as the key step, the use of the same mercury derivative of the terminal-alkyne w-functionalised as intermediate. The first coupling reaction took place between methoxyallene and Grignard reagent of 1-tert-butoxy-6-bromo-hexan obtaining 1-tert-butoxy-non-8-yne, which is transformed in di[1-tert-butoxy-non-8-yne]mercury, the common intermediate in the synthesis of the two pheromones. In order to obtain (Z)-8-dodecene-1-yl acetate and (E)-8-dodecene-1-yl acetate, the mercury derivative was directly lithiated and then alkylated with 1-bromo-propan obtaining 1-tert-butoxy-dodec-8-yne. After acetylation of 1-tert-butoxy-dodec-8-yne and stereoselective reduction in the presence of NiP-2 catalyst gave (Z)-8-dodecene-1-yl acetate with 85 % isomeric purity. After reduction with lithium aluminium hydride of 1-tert-butoxy-dodec-8-yne and acetylation was obtained (E)-8-dodecene-1-yl acetate with 90% isomeric purity.

New synthesis of (9Z,12E)-9,12-tetradecadien-1-yl acetate, the sex pheromone of the indian meal moth Plodia interpunctella (Lepidoptera, Pyralidae), were developed. The synthesis was based on a C8+C2=C10 and C10+C4=C14 coupling scheme. The route involves, as the key step, the use of the mercury derivative of the terminal-alkyne -functionalised as intermediate.The first coupling reaction took place between 1-tert-butoxy-8-bromo-octane and lithium acetylide-ethylendiamine complex obtaining 1-tert-butoxy-dec-9-yne, which is transformed in di[tert-butoxy-dec-9-yne]mercury.In the second coupling reaction, the mercury derivative was directly lithiated and then alkylated with (E)-1-bromo-2-butene obtaining 1-tert-butoxy-(9-yne,12E)-9,12-tetradecaenyne. After stereoselective reduction in the presence of NiP-2 catalyst and acetylation gave (9Z,12E)-9,12-tetradecadien-1-yl acetate with 82% isomeric purity.

Exo‐ and Endohormones. XI. Synthesis of Monounsaturated Sex Pheromones of Lepitopetra via α‐Diketones α‐Diketones (5), prepared starting either with cyanohydrines (1) or with N,N‐diethyl oxamate (6), were converted via the dihydrazones (11) into acetylenes (12). Replacement of the protecting group by the acetate group and partial stereoselective reduction of the triple bond led finally to the title compounds.

Title compound (V) is synthesized starting from diol (I) using the lithiation and subsequent alkylation of di(t‐butoxy‐dodecyne)mercury (II) as the key step.

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