Vinyllithium

Source: Wikipedia, the free encyclopedia.
Vinyllithium
Identifiers
3D model (
JSmol
)
3587231
ChEBI
ChemSpider
ECHA InfoCard
 100.011.844 Edit this at Wikidata
EC Number
  • 213-028-5
723
  • InChI=1S/C2H3.Li/c1-2;/h1H,2H2;
    Key: PGOLTJPQCISRTO-UHFFFAOYSA-N
  • [Li]C=C
Properties
C2H3Li
Molar mass 33.99 g·mol−1
Appearance white solid
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 pyrophoric
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Vinyllithium is an

organolithium compound with the formula LiC2H3. A colorless or white solid, it is encountered mainly as a solution in tetrahydrofuran (THF). It is a reagent in synthesis of organic compounds, especially for vinylations.[1]

Preparation and structure

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

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,[1]

Like most organolithium compounds, vinyllithium crystallizes from THF as a cluster compound as a cubane-type cluster.[2]

Structure of [LiC2H3(THF)]4.

Reactions

Vinyllithium is used to install vinyl groups on metal-based reagents, i.e., vinylations. It is a precursor to vinylsilanes, vinylcuprates, and vinylstannanes.[3] It adds to ketones compounds to give allylic alcohols. Vinylmagnesium bromide is often used in place of vinyllithium.[4]

Alternative reagents

Vinyl magnesium bromide, a Grignard reagent, is in many ways easier to generate in the laboratory and behaves similarly to vinyllithium.[5]

References

  1. ^
    ISBN 978-0-471-93623-7
    ..
  2. doi:10.1039/C39920000903
    .
  3. doi:10.15227/orgsyn.069.0080
    .
  4. doi:10.15227/orgsyn.039.0010
    .
  5. doi:10.15227/orgsyn.068.0116.{{cite journal}}: CS1 maint: multiple names: authors list (link
    )
Retrieved from "https://en.wikipedia.org/w/index.php?title=Vinyllithium&oldid=1177967816"