Vinyllithium is an

organolithium compound In organometallic chemistry, organolithium reagents are chemical compounds that contain carbon–lithium (C–Li) bonds. These reagents are important in organic synthesis, and are frequently used to transfer the organic group or the lithium atom ...

with the formula LiC₂H₃. A colorless or white solid, it is encountered mainly as a solution in

tetrahydrofuran Tetrahydrofuran (THF), or oxolane, is an organic compound with the formula (CH2)4O. The compound is classified as heterocyclic compound, specifically a cyclic ether. It is a colorless, water-miscible organic liquid with low viscosity. It is ma ...

(THF). It is a

reagent In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a ...

in synthesis of organic compounds..

Preparation and structure

Solutions of vinyllithium are prepared by lithium-halogen exchange reactions. A halide-free route entails reaction of

tetravinyltin Tetravinyltin (also known as tetravinylstannane) is an organotin compound with a chemical formula of C8H12Sn. Uses Upon heating, a mixture of tetravinyltin and tin tetrachloride undergo disproportionation to form divinyltin dichloride, vinyltin ...

with

butyllithium Butyllithium may refer to one of 5 isomeric organolithium reagents of which 3 are commonly used in chemical synthesis: * ''n''-Butyllithium, abbreviated BuLi or nBuLi * ''sec''-Butyllithium, abbreviated ''sec''-BuLi or sBuLi, has 2 stereoisomers, ...

: :Sn(CH=CH₂)₄ + 4 BuLi → SnBu₄ + 4 LiCH=CH₂ The reaction of ethylene and lithium affords vinyl lithium and lithium hydride, together with other organolithium compounds, Like most organolithium compounds, vinyllithium crystallizes from THF as a cluster compound as a

cubane-type cluster A cubane-type cluster is an arrangement of atoms in a molecular structure that forms a cube. In the idealized case, the eight vertices are symmetry equivalent and the species has Oh symmetry. Such a structure is illustrated by the hydrocarbon cub ...

Reactions

Vinyllithium is used to install vinyl groups on metal-based reagents, being a precursor to vinylsilanes, vinylcuprates, and vinylstannanes. It adds to ketones compounds to give allylic alcohols. Vinylmagnesium bromide is often used in place of vinyllithium.

References

{{Lithium compounds Lithium compounds Organolithium compounds Vinyl compounds