Preparation of streochemically pure sex pheromone components of the pine sawfly (Neodiprion sertifer) and field tests of the synthetic compounds.

Field Response of Male Pine Sawflies, Neodiprion sertifer (Diprionidae), to Sex Pheromone Analogs in Japan and Sweden

“…Chemicals used were of high chemical and stereogenic purities, and were synthesized according to Högberg et al (1990), Hedenström et al (1992), Tai et al (1990Tai et al ( , 1992, and Hedenström et al (2002). Purity details and abbreviations of compounds used below are given in Table 1.…”

“…c a The hyphen in acronyms indicates a missing methyl group relative to compound 1 b Chemical purity % ð Þ : 100 Â Amount of the stereoisomers of the indicated compound=Amount of all compounds ð Þ. Stereochemical purity % ð Þ : 100 Â Amount of the indicated stereoisomer=Sum of amounts of all stereoisomers ð Þ c 1) Högberg et al (1990), Anderbrant et al (1992b), and Hedenström et al (2006), 2) Tai et al (1990), 3) Tai et al (1992), 4) Hedenström et al (1992) main attractant Anderbrant et al, 1995;Bergström et al, 1995), suggesting that the length of the carbon chain is an essential characteristic of the pheromone for a given species. On the other hand, these two, and several other Neodiprion species, also are attracted to two or more compounds in which the acetate group of the main pheromone compound has been replaced with other acyl moieties (Anderbrant et al, 1992a(Anderbrant et al, , 1997Anderbrant, 1999).…”

“…The most widespread diprionid species, N. sertifer, has a well characterized sex pheromone, with the acetate [(SSS) Ac] (Table 1) or propionate [(SSS)Pr] of (2S,3S,7S)-3,7-dimethyl-2-pentadecanol (diprionol) as the main component. The (2S,3R,7R)-isomer of the acetate [(SRR)Ac] can act as a synergist to these major components in certain geographic areas, as an antagonist in other areas, and can have no effect when added in other areas (Tai et al, 1990;Anderbrant et al, 1992bAnderbrant et al, , 2000. The (2S,3R,7S)-isomer of the acetate [(SRS) Ac] is able to replace the synergistic function of (SRR)Ac in Siberia and the antagonistic function in Europe, although, in the latter case, it has to be in much larger relative amounts (Anderbrant et al, 1992b.…”

Asymmetric heterogeneous catalytic hydrogenation; is it a useful tool for the synthetic organic chemist?

“…The modified catalyst recognises the re and si face of the substrate and allows the dissociated hydrogen to attack the side facing the catalyst surface. 72 Since the discovery of the so-called Izumi catalyst, several commercialised processes were developed, which utilised this hydrogenation: the reduction of methyl 2-methyl-oxobutirate, 79 methyl acetoacetate, 80 …”

Diastereoselective Hydrogenation in the Preparation of Fine Chemicals

“…(This means that a stoichiometric amount of the chiral molecule (auxiliary) must be used.) Several reviews of enantioselective hydrogenation have been published [3][4][5], and a number of successful applications have been described [6][7][8][9][10]. However, high enantioselectivity has been obtained only with a limited number of reactions and substrates [11,12].…”