In
organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the science, scientific study of the structure, properties, and reactions of organic compounds and organic matter, organic materials, i.e., matter in its various forms that contain ...
, vinylation is the process of attaching a
vinyl group () to a substrate. Many organic compounds contain vinyl groups, so the process has attracted significant interest, especially since the reaction scope includes substituted vinyl groups. The reactions can be classified according to the source of the vinyl group.
Nucleophilic vinyl reagents
Vinyl lithium and vinyl magnesium bromide are sources of "", which add to
ketone
In organic chemistry, a ketone is an organic compound with the structure , where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (a carbon-oxygen double bond C=O). The simplest ketone is acetone ( ...
s and
aldehyde
In organic chemistry, an aldehyde () (lat. ''al''cohol ''dehyd''rogenatum, dehydrogenated alcohol) is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred ...
s.
Vinylsiloxane and vinylboranes have also been used as sources of vinyl anion equivalents.These types of reactions require
catalyst
Catalysis () is the increase in rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quick ...
s such as those based on
palladium
Palladium is a chemical element; it has symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1802 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas (formally 2 Pallas), ...
.
Vinylation with alkenes
The
Heck reaction couples an unsaturated
halide with an
alkene
In organic chemistry, an alkene, or olefin, is a hydrocarbon containing a carbon–carbon double bond. The double bond may be internal or at the terminal position. Terminal alkenes are also known as Alpha-olefin, α-olefins.
The Internationa ...
.
Base and a
palladium catalyst are required. This reaction is a way to substitute alkenes.
Vinylation with acetylene
As originally developed by
Walter Reppe, acetylene participates in a variety of metal- or base-catalyzed reaction to afford vinyl derivatives.
Alcohols, thiols, and secondary amines add to acetylene to give the
vinyl ethers,
vinyl sulfides, and vinyl amines, respectively.
:

In the presence of metal catalysts,
carbon monoxide
Carbon monoxide (chemical formula CO) is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...
and acetylene react to give
acrylic acid
Acrylic acid (IUPAC: prop-2-enoic acid) is an organic compound with the formula CH2=CHCOOH. It is the simplest unsaturated carboxylic acid, consisting of a vinyl group connected directly to a carboxylic acid terminus. This colorless liquid has ...
or acrylic esters. The net reaction is vinylation of carbon monoxide.
:

:
Vinyl acetate
Preparing
vinyl esters typically requires indirect methods because vinyl alcohol is not a suitable reagent.
Vinyl acetate
Vinyl acetate is an organic compound with the Chemical formula, formula CH3CO2CH=CH2. This colorless liquid is the precursor to polyvinyl acetate, ethylene-vinyl acetate copolymers, polyvinyl alcohol, and other important industrial polymers.
Prod ...
, which is available on an industrial scale, can be used to produce other vinyl esters. The process is sometimes referred to as transvinylation. Higher esters of vinyl acetate have been used in the synthesis of
vinyl formate.
Alternatively, vinyl ethers can be prepared from alcohols by
iridium
Iridium is a chemical element; it has the symbol Ir and atomic number 77. This very hard, brittle, silvery-white transition metal of the platinum group, is considered the second-densest naturally occurring metal (after osmium) with a density ...
-catalyzed
transesterification
Transesterification is the process of exchanging the organic functional group R″ of an ester with the organic group R' of an alcohol. These reactions are often catalyzed by the addition of an acid or base catalyst. Strong acids catalyze the r ...
of vinyl esters, especially the widely available
vinyl acetate
Vinyl acetate is an organic compound with the Chemical formula, formula CH3CO2CH=CH2. This colorless liquid is the precursor to polyvinyl acetate, ethylene-vinyl acetate copolymers, polyvinyl alcohol, and other important industrial polymers.
Prod ...
:
[{{cite journal, title=Iridium-catalyzed Synthesis of Vinyl Ethers from Alcohols and Vinyl Acetate, author=Tomotaka Hirabayashi , author2=Satoshi Sakaguchi , author3=Yasutaka Ishii , journal=Org. Synth., year=2005, volume=82, page=55, doi=10.15227/orgsyn.082.0055, doi-access=free]
:ROH + CH
2=CHOAc → ROCH=CH
2 + HOAc
See also
*
Hydrovinylation,
ethylene
Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon–carbon bond, carbon–carbon doub ...
adds "across" an alkene double bond
References
Vinyl compounds
Vinyl esters