Methyl myrtenate

Essential oil analyses of note this year are of Buchu leaf (some p-menthane sulphur derivatives), Hyssopus officinalis (methyl myrtenate, 2-hydroxyisopinocamphone, pinic acid, and pinonic acid), Laggera aurita (m-menth-6-en-8-ol), some Cymbopogon species (up to 89% of unusual p-menthadienols), and Trichostema lanceolatum (55% p-menthen-4-ol). There... 

Hardie J., Isaacs R., Pickett J. A., Wadhams L. J. and Woodcock C. M. (1994) Methyl salicylate and (-)-(lR,5S)-myrtenal are plant-derived repellents for the black bean aphid. Aphis fabae Scop. (Homoptera Aphididae). J. Chem. Ecol. 20, 2847-2855. 

The essential oil contains mainly pinocam-phone, isopinocamphone, a- and P-pinenes, camphene, and a-terpinene, which together constitute about 70% of the oil. Other constituents present include pinocampheol, cineole, linalool, terpineol, terpinyl acetate, bomyl acetate, cw-pinic acid, cw-pinonic acid, myrtenic acid, myrtenol methyl ether, (i-2-hyckoxy-isopinocamphone, methyl myr-tenate, cadinene, and other unidentified compounds totaling more than 50 (karrer list... 

Jorgensen and Helmchen introduced the first example of synthetic use of a chiral silicon Lewis acid. They reported that chiral silylium salt (75), having a B(C6p5)4 anion, catalyzes the Diels-Alder reaction of 1,3-cyclohexadiene although the enantioselectivity is rather low [120]. Ghosez and coworkers developed another type of chiral silicon Lewis acid [121]. The silicon Lewis acid (76), derived from (-)-myrtenal, achieves a moderate enantioselectivity in the reaction of methyl acrylate with 1,3-cyclopentadiene (Scheme 9.48). 

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