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.

No abstract

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.

New and practical synthesis of (E)-11-tetradecen-1-yl acetate and (Z)-11-hexadecen-1-yl acetate were developed. The synthesis were based on a C12+C2=C14 and C12+C4=C16 coupling scheme. 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 was effected by adding 1-tert-butoxy-10-bromodecane to monosodate acetylene, obtained in situ from DMSO and sodium hydride. It was prepared 1-tert-butoxy-dodec-11-yne, which is transformed in di[tert-butoxy-dodec-11-yne]mercury, the common intermediate in the synthesis of the two pheromones. In order to obtain (E)-11-tetradecen-1-yl acetate, the mercury derivative was directly lithiated and then alkylated with 1-bromoethane obtaining 1-tert-butoxy-tetradec-11-yne. After reduction with lithium aluminium hydride of 1-tert-butoxy-tetradec-11-yne and acetylation gave (E)-11-tetradecen-1-yl acetate with 99 % isomeric purity. In order to obtain (Z)-11-hexadecen-1-yl acetate, the mercury derivative was directly lithiated and then alkylated with 1-bromobutane obtaining 1-tert-butoxy-hexadec-11-yne. After acetylation of 1-tert-butoxy-hexadec-11-yne and stereoselective reduction in the presence of NiP-2 catalyst gave (Z)-11-hexadecen-1-yl acetate with 90 % isomeric purity.

Were developed new and practical synthesis of (Z)-7-dodecene-1-yl acetate and (E)-9-dodecene-1-yl acetate. The routes involve, as the key step, the use of the mercury derivative of the terminal-alkyne w-functionalised as intermediate. The synthesis of (Z)-7-dodecene-1-yl acetate was based on a C6+C2=C8 and C8+C4=C12 coupling scheme, starting from 1,6-hexane-diol. The first coupling reaction took place between 1-tert-butoxy-6-bromo-hexane and lithium acetylide-ethylendiamine complex obtaining 1-tert-butoxy-oct-7-yne, which is transformed in di[tert-butoxy-oct-7-yne]mercury. The mercury derivative was directly lithiated and then alkylated with 1-bromobutane obtaining 1-tert-butoxy-dodec-7-yne. After acetylation and reduction with lithium aluminium hydride of 7-dodecyne-1-yl acetate gave (Z)-7-dodecene-1-yl acetate with 96 % purity. The synthesis of (E)-9-dodecene-1-yl acetate was based on a C8+C2=C10 and C10+C2=C12 coupling scheme, starting from 1,8-octane-diol. 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. The mercury derivative was directly lithiated and then alkylated with 1-bromoethane obtaining 1-tert-butoxy-dodec-9-yne. After reduction with lithium aluminium hydride of 1-tert-butoxy-(E)-9-dodecene and acetylation was obtained (E)-9-dodecene-1-yl acetate with 97 % purity.