Stereoselective Synthesis of trans-Olefins by the Copper-Mediated SN2′ Reaction of Vinyl Oxazines with Grignard Reagents. Asymmetric Synthesis of D-threo-Sphingosines.

Stereoselective synthesis of trans olefi

Stereoselective synthesis of trans olefins by the reaction of Wittig reagents with selenium. Formation of selenocarbonyl compounds

✍ Kentaro Okuma; Jun-ichi Sakata; Yuji Tachibana; Takumi Honda; Hiroshi Ohta 📂 Article 📅 1987 🏛 Elsevier Science 🌐 French ⚖ 243 KB

Wittig reagents were successfully changed to symmetrical olefins when treated with elemental selenium. The reaction proceeds through a selenocarbonyl intermediate, which existence was confirmed by Diels-Alder reaction. Phosphonium ylides (1) have been widely utilized for the synthesis of olefins' an