A new approach to conjugated dienes synthesis of the pheromones of lobesja botrana and bombyx morj

Stereoselective Synthesis of Enamides by a Peterson Reaction Manifold

“…The famous Peterson elimination 10-12 seems to meet these stringent criteria. Thus, we envisaged the use of epoxysilanes as starting materials which can be prepared by a variety of efficient methods. , Specifically, compounds trans - 7 and cis - 7 used as model substrates are conveniently obtained by reaction of vinylsilanes ( E )- 6 or ( Z )- 6 , respectively, with m -chloroperbenzoic acid or dimethyldioxirane . Silicon-directed epoxide ring opening with NaN 3 in a buffered medium 16 furnishes products 8 , which can be selectively reduced to the corresponding amino alcohols 9 in many different ways .…”

Stereoselective Construction of (E,Z)‐1,3‐Dienes and Its Application in Natural Product Synthesis

“…[140,141] Later, Alexakis described the synthesis of two lepidopteran sex pheromones: bombykol and (E,Z)-7,9-dodecadienyl acetate, the pheromone of the European grapevine moth (Lobesia botrana). [142] The methodology relied on the regio-and stereoselective ring-opening of trans or cis epoxysilanes by Z-alkenyl cuprates, in the presence of a Lewis acid, to give either threo-or erythro-β-hydroxysilanes, respectively. An anti-or syn-elimination step (acidic or basic conditions) affords (E,Z)-1,3-dienes with high selectivities.…”

syn-β-Hydroxyallylic Silanes from Terminal Epoxide α-Lithiation–Silylation and Alkenylation: Application to the Tetrahydrofuran Portion of the Lytophilippines

“…To examine the scope of this methodology for accessing more substituted syn -β-hydroxyallylic silanes, mono-, di- or trialkyl-substituted alkenylmagnesium bromides were also explored under the above conditions, but only starting epoxysilane 5a was observed. More substituted syn -β-hydroxyallylic silanes 7 – 9 could be successfully obtained from epoxysilane 5a by adopting Alexakis and Jachiet’s method for BF 3 -assisted ring opening of (less-hindered) TMS-substituted epoxides with higher-order Z -alkenylcuprates (Scheme ).…”