organic chemistry Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, ...

, vinylation is the process of attaching a

vinyl group In organic chemistry, a vinyl group (abbr. Vi; IUPAC name: ethenyl group) is a functional group with the formula . It is the ethylene (IUPAC name: ethene) molecule () with one fewer hydrogen atom. The name is also used for any compound contai ...

() 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 ketones and

aldehyde In organic chemistry, an aldehyde () is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl grou ...

s. Vinylsiloxane and vinylboranes have also been used as sources of vinyl anion equivalents.These types of reactions require

catalyst Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

s such as those based on

palladium Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself na ...

Vinylation with alkenes

The

Heck reaction The Heck reaction (also called the Mizoroki–Heck reaction) is the chemical reaction of an unsaturated halide (or triflate) with an alkene in the presence of a base and a palladium catalyst (or palladium nanomaterial-based catalyst) to form a sub ...

couples an unsaturated halide with an

alkene In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, an ...

. Base and a palladium catalyst are required. This reaction is a way to substitute alkenes. Heck naproxen

In hydrovinylation, ethylene adds "across" an alkene double bond: : This kind of reaction requires a metal catalyst. In principle, alkenes other than ethylene could be employed. In a stoichiometric version of a hydrovinylation reaction, nucleophiles add to an electrophilic transition metal alkene complex, forming a C-C bond. The resulting metal alkyl undergoes beta-hydride elimination, liberating the vinylated product.

Vinylation with acetylene

As originally developed by

Walter Reppe Walter Julius Reppe (29 July 1892 in Göringen – 26 July 1969 in Heidelberg) was a German chemist. He is notable for his contributions to the chemistry of acetylene. Education and career Walter Reppe began his study of the natural sciences ...

, 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. : Reppe-chemnistry-vinylization

In the presence of metal catalysts,

carbon monoxide Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simple ...

and acetylene react to give

acrylic acid Acrylic acid (IUPAC: propenoic 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 a ...

or acrylic esters. The net reaction is vinylation of carbon monoxide. : Reppe-chemistry-carbonmonoxide-01

Vinyl acetate

The preparation of

vinyl ester left, 144px, Vinyl acetate is a commercially important monomer that is classified as a vinyl ester (i.e. an ester of vinyl alcohol). Vinyl ester refers to esters formerly derived from vinyl alcohol. Commercially important examples of these mono ...

s typically requires indirect methods because vinyl alcohol is not a suitable reagent.

Vinyl acetate Vinyl acetate is an organic compound with the formula CH3CO2CH=CH2. This colorless liquid is the precursor to polyvinyl acetate and ethene-vinyl acetate copolymers, important industrial polymers. Production The worldwide production capacity of v ...

, 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 with the symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, it is considered the second-densest naturally occurring metal (after osmium) with a density of ...

-catalyzed

transesterification In organic chemistry, transesterification is the process of exchanging the organic 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. The reaction ca ...

of vinyl esters, especially the widely available

vinyl acetate Vinyl acetate is an organic compound with the formula CH3CO2CH=CH2. This colorless liquid is the precursor to polyvinyl acetate and ethene-vinyl acetate copolymers, important industrial polymers. Production The worldwide production capacity of v ...

:{{cite journal, title=Iridium-catalyzed Synthesis of Vinyl Ethers from Alcohols and Vinyl Acetate, authors=Tomotaka Hirabayashi, Satoshi Sakaguchi, Yasutaka Ishii, journal=Org. Synth., year=2005, volume=82, pages=55, doi=10.15227/orgsyn.082.0055, doi-access=free :ROH + CH₂=CHOAc → ROCH=CH₂ + HOAc

References

Vinyl compounds Vinyl esters