Steroidal selenoxides diastereoisomeric at selenium; syn-elimination, absolute configuration, and optical rotatory dispersion characteristics

Recent Advances in Organoselenium Chemistry

“…It was not until 1970, when the formation of alkenes by decomposition of selenoxides was found to be a very versatile process proceeding under mild conditions 1b. Since that time this reaction has attracted chemists and still nowadays, this method is used to introduce double bonds into molecules.…”

Labeled bile acids III: Deuterium labeled chenodeoxycholic and ursodeoxycholic acids

“…l a t e d e s t e r 13 a r e i s o l a t e d ( s t r u c t u r e not proven, see Experimental S e c t i o n ) , the (E)-olefins 14 and 22 a r e postulated to have been derived from the oxidative synelimination of an intermediate with a pseudo-threo configuration (7,9). Scheme I11 uses cholic acid a s s t a r t i n g material.…”

Organocatalytic asymmetric selenofunctionalization of tryptamine for the synthesis of hexahydropyrrolo[2,3-b]indole derivatives

“…Selenofunctionalization of carbon–carbon double bonds provides practicable opportunities for rapid construction of molecule complexity [1–8], because the versatile carbon–selenium bond could either stabilize carbanions [9–10], serve as a radical precursor [11–13], or undergo a syn -selective oxidative elimination via the selenoxide [14–15]. A widely accepted mechanism suggests that a key discrete seleniranium ion intermediate is initially formed, and then trapped by internal amine through nucleophilic attack to furnish the product.…”