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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, J ...
, hydrovinylation is the formal
insertion Insertion may refer to: * Insertion (anatomy), the point of a tendon or ligament onto the skeleton or other part of the body * Insertion (genetics), the addition of DNA into a genetic sequence *Insertion, several meanings in medicine, see ICD-10-PC ...
of 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 ...
into the C-H bond of
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 double bonds). Ethylene ...
(). The more general reaction, hydroalkenylation, is the formal insertion of an alkene into the C-H bond of any terminal alkene. The reaction is catalyzed by
metal complex A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...
es. A representative reaction is the conversion of
styrene Styrene () is an organic compound with the chemical formula C6H5CH=CH2. This derivative of benzene is a colorless oily liquid, although aged samples can appear yellowish. The compound evaporates easily and has a sweet smell, although high concen ...
and ethylene to 3-phenybutene: :\ce + \longrightarrow \ce


Ethylene dimerization

The dimerization of ethylene gives 1-butene is another example of a hydrovinylation. In the Dimersol and Alphabutol Processes, alkenes are dimerized for the production of gasoline and for comonomers such as 1-butene. These processes operate at several refineries across the world at the scales of about 400,000 tons/year (2006 report). 1-Butene is amenable to isomerization to 2-butenes, which is used in
Olefin conversion technology Olefin Conversion Technology, also called the Phillips Triolefin Process, is the industrial process that interconverts propylene with ethylene and 2-butenes. The process is also called the ethylene to propylene (ETP) process. In ETP, ethylene is di ...
to give propylene.


Hydroarylation

Hydroarylation is again a special case of hydrovinylation. Hydroarylation has been demonstrated for alkyne and alkene substrates. An early example was provided by the
Murai reaction In organic chemistry, the Murai reaction is an organic reaction that uses C-H activation to create a new C-C bond between a terminal or strained internal alkene and an aromatic compound using a ruthenium catalyst. The reaction, named after Shinj ...
, which involves the insertion of alkenes into a C-H bond of
acetophenone Acetophenone is the organic compound with the chemical formula, formula C6H5C(O)CH3. It is the simplest aromatic ketone. This colorless, viscous liquid is a precursor to useful resins and fragrances. Production Acetophenone is formed as a byprodu ...
. The keto group directs the regiochemistry, stabilizing an aryl intermediate. When catalyzed by palladium carboxylates, a key step is
electrophilic aromatic substitution Electrophilic aromatic substitution is an organic reaction in which an atom that is attached to an aromatic system (usually hydrogen) is replaced by an electrophile. Some of the most important electrophilic aromatic substitutions are aromatic n ...
to give a Pd(II) aryl intermediate. Gold behaves similarly. Hydropyridination is a similar reaction, but entails addition of a pyridyl-H bond to alkenes and alkynes.


In organic synthesis

As first reported by Alderson, Jenner and Lindsey, hydrovinylation uses rhodium- and ruthenium-based catalysts. Catalysts based on iron, cobalt, nickel, and palladium have also been demonstrated. The addition can be done highly regio- and stereoselectively, the choices of metal centers, ligands, substrates and counterions often play very important role. N-heterocyclic carbene complexes of Ni allow the selective preparations of functionalized geminal olefins or 1,1-disubstituted alkenes.{{cite journal , author = Ho, C.-Y. , author2=He, L. , year = 2012 , pages = 1481–1483 , title = Shuffle Off the Classic Beta-Si Elimination by Ni-NHC Cooperation: Implication for C–C Forming Reactions Involving Ni-Alkyl-Beta-Silanes , issue = 10 , pmid = 22116100 , journal = Chem. Commun. , volume = 48 , doi = 10.1039/c1cc14593b


References

Alkenes Carbon-carbon bond forming reactions