Stereoselective Synthesis of (±)-(E)-6-Isopropyl-3,9-dimethyl-5,8-decadienyl Acetate, the Racemate of the Yellow Scale Pheromone, and Its (Z)-Isomer

Chemistry of the pheromones of mealybug and scale insects

“…Mori and coworkers developed three syntheses of the pheromone in rapid succession, with the rst aimed at determining the double bond geometry, 51 the second at developing a chiral synthesis producing one enantiomer, 52 and the third at providing both enantiomers. 53 These syntheses were long and low-yielding, have been previously reviewed in detail, and so they are only summarized here.…”

Stereoselective Synthesis of (S,E)-6-Isopropyl-3,9-dimethyl-5,8-decadienyl Acetate, the (S)-Enantiomer of the Yellow Scale Pheromone

“…The ether solution was washed with water and brine, dried over magnesium sulfate and concentrated in vacuo. 3.00 (tH, s, -OH), 3.47 (2H, t, J = 7 Hz), 4.7 ~5.95 (4H, m); GLC (column, 3% SE-30, l.5m x 2mm at 140~200°C (+6°C/min); carrier gas, N2, 1.0kg/cm 2 ): tR 2.0min (98%), impurity at 5.7min. Anal.…”

“…The alcohol (± )-3 was successively treated with potassium hydride and iodomethyltri-n-butyltin 5 ) to give an allyl stannylmethyl ether 4. Without isolation this was treated with n-butyllithium, which resulted in tin-lithium exchange followed by [2,3]-sigmatropic rearrangement to an (E)-dienol5 (98% purity by GLC). Oxidation of 5 with pyridinium dichromate 6 ) gave an aldehyde 6.…”

Tabulations of Selected Methods of Syntheses That Are Frequently Employed for Insect Sex Pheromones, Emphasizing the Literature of 1977–1982

“…(1981), Pirkle and Adams (1979), Tsuboi et a1. (1982) Mori ( Babler and Invergo (1979), Chuman et al (1979), Kocienski and Ansell (1977), Labovitz et al (1975), Mori and Kuwahara (1982), Pirkle and Boeder (1978), Pirkle and Adams (1979), Place et al (1978), Suguro et al (1981 Hammoud and , Place et al (1978), Still and Mitra (1978) Still (1979) Mori (1978) Suguro et al (1981) Bartlett et al (1982) Rossi and Marasco (1980) Tamada et al (1978) The following reactions were mediated by copper as cuprates RMgX, alkyl halide or tosylate Descoins et al (1977), Guss et al (1983), Mandai et al (1979), Mori et al (1978bMori et al ( , 1981a, Rossi (1978b), Shani (1979), Sonnet and Heath (1982a,b), Suguro and Mori (1979b) …”