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A highly selective synthesis of 2-methyl-cis-Z 8-epoxyoctadecane --the racemic analog of the sex pheromone of the gypsy moth Porthetria dispar L. --(Z)-disparlure --has been developed that is based on the functionally differentiated partial ozonization of cycloocta-l Z, 5Z-diene. A whole series of syntheses is known [1-10] for the biologically active racemic analog of (Z)-disparlure --the sex pheromone of the gypsy moth Porthetria dispar L., which also exhibits attractant activity in relation to the black arches moth Lymantria monarcha Z. [11] and has the structure of 2-methyl-c/s-7,8-epoxyoctadecane (1). We have reported a synthesis of the pheromone (1) based on the selective (at one multiple bond) ozonolysis of cyclooctadeca-lZ,5Z-diene (2) and a two-stage conversion of the peroxide product into oct-4Z-ene 1,8-dibromide and its subsequent selective coupling with beptyl-and isobutylmagnesium bromides [12, 13]. The yield of pheromone (1) in the synthesis described amounted to 25 %, calculated on the initial butadiene dimer. The construction of the required carbon skeleton of the desired compound can be achieved with a higher selectivity from the product of the functionally differentiated partial ozonolysis of diene (2) when the peroxide product is subjected to hydrolytic cleavage to derivatives of a o.~-oxocarboxylic acid [14]. We have synthesized a number of pheromones with an acetogenin structure in this way [15][16][17][18][19][20][21].Using this approach, we have performed the synthesis of pheromone (1) with a substantially higher overall yield [about 60%, calculated on the initial butadiene dimer (2)] than in the earlier synthesis [13]. This is explained by the highly selective transformations to the final functional groups in the ozonolysis product--methyl 8,8-dimethoxyoct-4Z-enoate (3), the formation of which and its conversion into 1,1-dimethoxy-8-tosyloxyoct-4Z-ene (4) we have described previously [16]. The coupling of the tosylate (4) with beptylmagnesium bromide in the presence of Li2CuC14 takes p!ace smoothly with a high yield of the required product --1,1-dimethoxypentadec-4Z-ene (5).To complete the construction of the desired carbon skeleton we eliminated the acetal protection in (5) and converted the resulting aldehyde (6) by treatment with i-Bu2AIH into pentadec-4Z-en-l-ol (7), which, in the form of the tosylate (8) was coupled with isobutylmagnesium bromide, giving, under mild conditions, a high yield of 2-methyloctadec-7-ene exclusively with the (Z)-configuration, confirmation of which was given by the positions of the signals of the vinyl and allyl carbon atoms in the 13C NMR spectrum of the (Z)-alkene (9) (8 129.2 and 27.25 ppm, respectively, while for its (E)-isomer the corresponding signals are found in the regions of 8 132.5 and 32.69 ppm [1]).Signals in the regions of ~ 55.97 ppm (C 7 and C 8) and 28.03 ppm (C 6 and C 9) for the epoxide (1) obtained by the interaction of the Z-alkene (9) withp-methoxycarbonylperbenzoic acid also unambiguously conftrmed its assignment to the (Z)series: ...

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Research from the last 20 years on the use of ozonolysis of cyclic and acyclic mono-and dienes and aromatic compounds in various steps of the total synthesis of insect pheromones and juvenoids was reviewed.