Syntheses with sulfones XLIX : stereo- and enantioselective synthesis of (s)-(-)-3,9-dimethyl 6-(1-methylethyl) (e)-5,8-decadien 1-ol acetate, sexual pheromone of yellow scale.

✍ Scribed by E. Alvarez; T. Cuvigny; C.Hervé du Penhoat; M. Julia

• Publisher: Elsevier Science
• Year: 1988
• Tongue: French
• Weight: 566 KB
• Volume: 44
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(01)85099-7

✦ Synopsis

The 8 tereo-and e?&mtioee~ective 8ynthQ8iS of the yeltaw scale pheromone, (Sl-(-I-9-dimetkyt B-il-metk&EetkyLJ (El-5,8-decadien l-02 acetate, ~PM 3-CRJ-l+J-valerolacto~e 2 and ii-methyl 3-pentenyZJsuZfonyZ~ benziene 8 ie described. T~Q key step is the introduction of the isopropyt group by the etereoee~ectiv~ cross-coupting reaction of the dieneeulfone 12 with iQopropyLmagneeium oktoride in the presence of PeCE3. -The yellow scale, Aontdiella citrina, is a severe pest of ornamental plants and citrus fruit in California and Japan. In 1979 Gieselmann and Coil. 1 isolated the sexual pheromone of yellow scale, (E)-3,9-di~thyl 6-isopropyl 5,8-decadien l-y1 acetate 13b. The structure assig-nment was confinned by two independent syntheses of both (El-and (Z)-isomers as racemates 2.3 . Recently, Mori and Kuwahara 4 have prepared both R-(t) and S-t-) enantiomers of 13b from optically active (RI-(+I-methylcitronellate in 10% and 7% overall yields. Only the latter S enantlomer is biologically active.