Stereoselective synthesis of the major component of a mosquito oviposition attractant pheromone from a β-lithiopropionate equivalent

Acylvinyl and Vinylogous Synthons

“…Therefore, direct deprotonation to achieve acrylic or acrylate reagents type 181 (X = OR, SR; Z = CO 2 Li or CO 2 R) followed by reaction with electrophilic−nucleophilic species, as for instance with aldehydes, ketones, α,β-unsaturated carboxylates, or epoxides, represents an access to butenolides, tetronates, cyclopentenones, or δ-lactones, respectively. ,− Examples of these types of reagents are β-C-lithiated acrylates 183 , which are intermediates for the synthesis of tetronates 184 after reaction with aldehydes (Scheme ). ,,,, Using α-chloroaldehydes, erythro -dihydroxycarboxylic acid lactones have been prepared starting from dianion 181 (Z = CO 2 Li, X = SEt) − or even β-amino 89 acrylate derivatives and has been employed, for example, for the synthesis of a (−)-vertinolide precursor .…”

Production of (5R,6S)-6-Acetoxy-5-hexadecanolide, the Mosquito Oviposition Pheromone, from the Seed Oil of the Summer Cypress Plant, Kochia scoparia (Chenopodiaceae)

“…The characterization of the oviposition pheromone 1a has provided the impetus for several asymmetric syntheses and large scale racemic routes, respectively, as a challenge for synthetic chemists and to provide material for field testing (Laurence and Pickett, 1982 Fuganti et al, 1982;Mori and Otsuka, 1983;Sato et al, 1984;Lin et al, 1985;Machiya et al, 1985;Ochiai et al, 1985;Barua and Schmidt, 1986;Jefford et al, 1986;Ko and Eliel, 1986;Dawson et al, 1990;Coutrout and Bomont, 1994;Gravierpelletier et al, 1995;Henkel et al, 1997). Although the various synthesis routes cited above can provide multigram quantities of 1a, the economic circumstances of the less developed countries make control strategies for Cx.…”

Bidirectional Synthesis of 6-Acetoxy-5-hexadecanolide, the Mosquito Oviposition Pheromone of Culex quinquefasciatus, from a C2-Symmetric Building Block Using Olefin Metathesis Reactions

“…This synthesis required multiple synthetic steps, several protecting group manipulations, and chromatographic separations of diastereomers. Since then, numerous stereoselective syntheses of 1 or its stereoisomers have been reported, which reflect the rapid progress in synthetic methodology since the early 1980s. − The two most recent approaches to this target molecule use a chemoenzymatic and an organocatalytic , epoxidation–lactonization sequence. The first example for an olefin metathesis based approach involves a sequence of cross-metathesis (CM) of a fatty acid, epoxidation, and lactonization and furnishes MOP ( 1 ) along with “other isomers” .…”