Organolithium reagents vinyllithium

The asymmetric addition of organolithium reagents to arylox azolines has been used to construct highly complex polycyclic terpene structures found in natural products. For example, the asymmetric addition of vinyllithium to chiral naphthyloxazoline 3 followed by treatment of the resulting anionic intermediate with iodoethyl dioxolane 61... 

ALKYLMETAL HALIDES, ALKYLMETALS ARYLMETALS, 1 - ARYL-1 -VINYLLITHIUM DERIVATIVES GRIGNARD REAGENTS, HALO-ARYLMETALS ORGANOLITHIUM REAGENTS... 

Early work has shown that the reaction of simple organolithium reagents with oxiranes lead mainly to products from a- or -deprotonation and not from the desired ring opening reaction. However, some reactions of methyllithium , aUyllithium , aryllithiums" , and vinyllithium/potassium reagents " with oxiranes are reported (Scheme 36). 

The first report of an external chiral ligand-mediated enantioselective addition of an organolithium reagent to an imine appeared in 1990 (Tomioka, in this volume) [27]. Tomioka and coworkers found that 1,2-addition of MeLi, n-BuLi and vinyllithium to the 4-methoxyphenylimine of benzaldehyde 15 gave, in the presence of tridentate aminoether 16, the corresponding tertiary amines 17 in excellent yields and good ees (71-77%) (Scheme 6). 

Preparative Methods attempts to produce synthetically useful quantities of ( )-2-(trimethylsilyl)vinyllithium (1) by reaction of lithium metal with (2-bromovinyl)trimethylsilane (2) failed because of concomitant metalation-elimination processes involving (1) and ) However, the transmetalation process between (2) and excess f-butyllithium has been effectively used to provide (1) (eq 1). An alternative route to (1) employs the transmetalation of a l-(trimethylsilyl)-2-stannylethylene with organolithium reagents (eqs 2 and 3). ... 

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