![N-butyllithium-tetramer-3D-balls](https://upload.wikimedia.org/wikipedia/commons/9/97/N-butyllithium-tetramer-3D-balls.png)
Organometallic chemistry is the study of organometallic compounds,
chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...
s containing at least one
chemical bond
A chemical bond is a lasting attraction between atoms or ions that enables the formation of molecules and crystals. The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds, or through the sharing of ...
between a
carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent
In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...
atom of an
organic molecule
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. Th ...
and a
metal
A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typicall ...
, including
alkali
In chemistry, an alkali (; from ar, القلوي, al-qaly, lit=ashes of the saltwort) is a basic, ionic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a ...
,
alkaline earth
The alkaline earth metals are six chemical elements in group 2 of the periodic table. They are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).. The elements have very similar properties: they are al ...
, and
transition metals
In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. They are the elements that ca ...
, and sometimes broadened to include
metalloids
A metalloid is a type of chemical element which has a preponderance of properties in between, or that are a mixture of, those of metals and nonmetals. There is no standard definition of a metalloid and no complete agreement on which elements are ...
like boron, silicon, and selenium, as well.
Aside from bonds to
organyl
In organic and organometallic chemistry, an organyl group is an organic substituent with one (sometimes more) free valence(-s) at a carbon atom.. The term is often used in chemical patent literature to protect claims over a broad scope.
Exam ...
fragments or molecules, bonds to 'inorganic' carbon, like
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 ...
(metal
carbonyls
In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups. A compound containing a ...
),
cyanide
Cyanide is a naturally occurring, rapidly acting, toxic chemical that can exist in many different forms.
In chemistry, a cyanide () is a chemical compound that contains a functional group. This group, known as the cyano group, consists of ...
, or
carbide
In chemistry, a carbide usually describes a compound composed of carbon and a metal. In metallurgy, carbiding or carburizing is the process for producing carbide coatings on a metal piece.
Interstitial / Metallic carbides
The carbides of th ...
, are generally considered to be organometallic as well. Some related compounds such as
transition metal hydride
Transition metal hydrides are chemical compounds containing a transition metal bonded to hydrogen. Most transition metals form hydride complexes and some are significant in various catalytic and synthetic reactions. The term "hydride" is used loo ...
s and
metal phosphine complexes are often included in discussions of organometallic compounds, though strictly speaking, they are not necessarily organometallic. The related but distinct term "
metalorganic compound" refers to metal-containing compounds lacking direct metal-carbon bonds but which contain organic ligands. Metal β-diketonates, alkoxides, dialkylamides, and metal phosphine complexes are representative members of this class. The field of organometallic chemistry combines aspects of traditional
inorganic
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemist ...
and
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.; ...
.
Organometallic compounds are widely used both stoichiometrically in research and industrial chemical reactions, as well as in the role of catalysts to increase the rates of such reactions (e.g., as in uses of
homogeneous catalysis
In chemistry, homogeneous catalysis is catalysis by a soluble catalyst in a solution. Homogeneous catalysis refers to reactions where the catalyst is in the same phase as the reactants, principally in solution. In contrast, heterogeneous catalysi ...
), where target molecules include polymers, pharmaceuticals, and many other types of practical products.
Organometallic compounds
![Magnesium bis-cyclopentadienyl bottle](https://upload.wikimedia.org/wikipedia/commons/3/33/Magnesium_bis-cyclopentadienyl_bottle.jpg)
Organometallic compounds are distinguished by the prefix "organo-" (e.g., organopalladium compounds), and include all compounds which contain a bond between a metal atom and a carbon atom of an
organyl group
In organic and organometallic chemistry, an organyl group is an organic substituent with one (sometimes more) free valence(-s) at a carbon atom.. The term is often used in chemical patent literature to protect claims over a broad scope.
Exam ...
.
In addition to the traditional metals (
alkali metal
The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K),The symbols Na and K for sodium and potassium are derived from their Latin names, ''natrium'' and ''kalium''; these are still the origins of the names ...
s,
alkali earth metal
The alkaline earth metals are six chemical elements in group 2 of the periodic table. They are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).. The elements have very similar properties: they are all ...
s,
transition metals
In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. They are the elements that ca ...
, and
post transition metals
The metallic elements in the periodic table located between the transition metals and the chemically weak nonmetallic metalloids have received many names in the literature, such as ''post-transition metals'', ''poor metals'', ''other metals'', ...
),
lanthanides,
actinide
The actinide () or actinoid () series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. The actinide series derives its name from the first element in the series, actinium. The info ...
s, semimetals, and the elements
boron,
silicon
Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic tab ...
,
arsenic
Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but ...
, and
selenium
Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, ...
are considered to form organometallic compounds.
Examples of organometallic compounds include
Gilman reagent
A Gilman reagent is a lithium and copper ( diorganocopper) reagent compound, R2CuLi, where R is an alkyl or aryl. These reagents are useful because, unlike related Grignard reagents and organolithium reagents, they react with organic halides to ...
s, which contain
lithium
Lithium (from el, λίθος, lithos, lit=stone) is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid ...
and
copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...
, and
Grignard reagents, which contain
magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...
.
Tetracarbonyl nickel and
ferrocene
Ferrocene is an organometallic compound with the formula . The molecule is a complex consisting of two cyclopentadienyl rings bound to a central iron atom. It is an orange solid with a camphor-like odor, that sublimes above room temperature, a ...
are examples of organometallic compounds containing
transition metal
In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. They are the elements that ca ...
s. Other examples of organometallic compounds include
organolithium
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 ...
compounds such as
''n''-butyllithium (n-BuLi),
organozinc
Organozinc compounds in organic chemistry contain carbon (C) to zinc (Zn) chemical bonds. Organozinc chemistry is the science of organozinc compounds describing their physical properties, synthesis and reactions.The Chemistry of Organozinc Compoun ...
compounds such as
diethylzinc
Diethylzinc (C2H5)2Zn, or DEZ, is a highly pyrophoric and reactive organozinc compound consisting of a zinc center bound to two ethyl groups. This colourless liquid is an important reagent in organic chemistry. It is available commercially as a ...
(Et
2Zn),
organotin compounds such as
tributyltin hydride
Tributyltin hydride is an organotin compound with the formula (C4H9)3SnH. It is a colorless liquid that is soluble in organic solvents. The compound is used as a source of hydrogen atoms in organic synthesis.
Synthesis and characterization
The c ...
(Bu
3SnH),
organoborane
Organoborane or organoboron compounds are chemical compounds of boron and carbon that are organic derivatives of BH3, for example trialkyl boranes. Organoboron chemistry or organoborane chemistry is the chemistry of these compounds.
Organoboron ...
compounds such as
triethylborane
Triethylborane (TEB), also called triethylboron, is an organoborane (a compound with a B–C bond). It is a colorless pyrophoric liquid. Its chemical formula is or , abbreviated . It is soluble in organic solvents tetrahydrofuran and hexane.
Pr ...
(Et
3B), and
organoaluminium compounds such as
trimethylaluminium
Trimethylaluminium is one of the simplest examples of an organoaluminium compound. Despite its name it has the formula Al2( CH3)6 (abbreviated as Al2Me6 or TMA), as it exists as a dimer. This colorless liquid is pyrophoric. It is an industriall ...
(Me
3Al).
A naturally occurring organometallic complex is
methylcobalamin
Methylcobalamin (mecobalamin, MeCbl, or MeB) is a cobalamin, a form of vitamin B. It differs from cyanocobalamin in that the cyano group at the cobalt is replaced with a methyl group. Methylcobalamin features an octahedral cobalt(III) centre and ...
(a form of
Vitamin B12), which contains a
cobalt
Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, p ...
-
methyl bond. This complex, along with other biologically relevant complexes are often discussed within the subfield of
bioorganometallic chemistry
Bioorganometallic chemistry is the study of biologically active molecules that contain carbon directly bonded to metals or metalloids. The importance of main-group and transition-metal centers has long been recognized as important to the function o ...
.
File:Ferrocene.svg, Ferrocene
Ferrocene is an organometallic compound with the formula . The molecule is a complex consisting of two cyclopentadienyl rings bound to a central iron atom. It is an orange solid with a camphor-like odor, that sublimes above room temperature, a ...
is an archetypal organoiron complex. It is an air-stable, sublimable compound.
File:Cobaltocene.svg, Cobaltocene
Cobaltocene, known also as bis(cyclopentadienyl)cobalt(II) or even "bis Cp cobalt", is an organocobalt compound with the formula Co(C5H5)2. It is a dark purple solid that sublimes readily slightly above room temperature. Cobaltocene was discovere ...
is a structural analogue of ferrocene, but is highly reactive toward air.
File:HRh(CO)P3again.png, Tris(triphenylphosphine)rhodium carbonyl hydride
Carbonyl hydrido tris(triphenylphosphine)rhodium(I) arbonyl(hydrido)tris(triphenylphosphane)rhodium(I)is an organorhodium compound with the formula hH(CO)(PPh3)3(Ph = C6H5). It is a yellow, benzene-soluble solid, which is used industrially for ...
is used in the commercial production of many aldehyde-based fragrance
An aroma compound, also known as an odorant, aroma, fragrance or flavoring, is a chemical compound that has a smell or odor. For an individual chemical or class of chemical compounds to impart a smell or fragrance, it must be sufficiently ...
s.
File:Zeise'sSalt.png, Zeise's salt
Zeise's salt, potassium trichloro(ethylene)platinate(II), is the chemical compound with the formula K platinum">PtCl3(C2H4).html" ;"title="platinum.html" ;"title="/nowiki>PtCl3(C2H4)">platinum.html"_;"title="/nowiki>platinum">PtCl3(C2H4)H2O.__Th ...
is an example of a transition metal alkene complex
In organometallic chemistry, a transition metal alkene complex is a coordination compound containing one or more alkene ligands. Such compounds are intermediates in many catalytic reactions that convert alkenes to other organic products.Elschenbro ...
.
File:Trimethylaluminium-from-xtal-3D-bs-17.png, Trimethylaluminium
Trimethylaluminium is one of the simplest examples of an organoaluminium compound. Despite its name it has the formula Al2( CH3)6 (abbreviated as Al2Me6 or TMA), as it exists as a dimer. This colorless liquid is pyrophoric. It is an industriall ...
is an organometallic compound with a bridging methyl group
In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in ma ...
. It is used in the industrial production of some alcohols.
File:Dimethylzinc-3D-balls.png, Dimethylzinc
Dimethylzinc, also known as Zinc methyl, DMZ, or DMZn is a colorless volatile liquid Zn(CH3)2, formed by the action of methyl iodide on zinc at elevated temperature or on zinc sodium alloy.
:2Zn + 2CH3I → Zn(CH3)2 + ZnI2
The sodium assists the ...
has a linear coordination. It is a volatile pyrophoric liquid that is used in the preparation of semiconducting films.
File:Lithium-diphenylcuprate-etherate-dimer-from-xtal-2D-skeletal.png, Lithium diphenylcuprate bis(diethyl etherate) is an example of a Gilman reagent
A Gilman reagent is a lithium and copper ( diorganocopper) reagent compound, R2CuLi, where R is an alkyl or aryl. These reagents are useful because, unlike related Grignard reagents and organolithium reagents, they react with organic halides to ...
, a type of organocopper complex frequently employed in organic synthesis.
File:AdoCbl-ColorCoded.png, Adenosylcobalamin
Adenosylcobalamin (AdoCbl), also known as coenzyme B12, cobamamide, and dibencozide, is, along with methylcobalamin (MeCbl), one of the biologically active forms of vitamin B12.
Adenosylcobalamin participates as a cofactor in radical-mediated 1,2 ...
is a cofactor required by several crucial enzymatic reactions that take place in the human body. It is a rare example of a metal (cobalt) alkyl in biology.
File:IronPentacarbonylStructure.png, Iron(0) pentacarbonyl is a red-orange liquid prepared directly from the union of finely divided iron and carbon monoxide gas under pressure.
File:Tc99 sestamibi 2D structure.svg, Technetium 99mTcsestamibi">sup>99mTcsestamibi is used to image the heart muscle in nuclear medicine.
Distinction from coordination compounds with organic ligands
Many
complex
Complex commonly refers to:
* Complexity, the behaviour of a system whose components interact in multiple ways so possible interactions are difficult to describe
** Complex system, a system composed of many components which may interact with each ...
es feature
coordination bond
In coordination chemistry, a coordinate covalent bond, also known as a dative bond, dipolar bond, or coordinate bond is a kind of two-center, two-electron covalent bond in which the two electrons derive from the same atom. The bonding of metal io ...
s between a metal and organic
ligands. Complexes where the organic ligands bind the metal through a
heteroatom
In chemistry, a heteroatom () is, strictly, any atom that is not carbon or hydrogen.
Organic chemistry
In practice, the term is usually used more specifically to indicate that non-carbon atoms have replaced carbon in the backbone of the molecula ...
such as oxygen or nitrogen are considered coordination compounds (e.g.,
heme A
Heme A (or haem A) is a heme, a coordination complex consisting of a macrocyclic ligand called a porphyrin, chelating an iron atom. Heme A is a biomolecule and is produced naturally by many organisms. Heme A, often appears a dichroic green/red wh ...
and
Fe(acac)3). However, if any of the ligands form a direct metal-carbon (M-C) bond, then the complex is considered to be organometallic. Although the IUPAC has not formally defined the term, some chemists use the term "metalorganic" to describe any coordination compound containing an organic ligand regardless of the presence of a direct M-C bond.
The status of compounds in which the
canonical anion has a negative charge that is shared between (
delocalized
In chemistry, delocalized electrons are electrons in a molecule, ion or solid metal that are not associated with a single atom or a covalent bond.IUPAC Gold Boo''delocalization''/ref>
The term delocalization is general and can have slightly dif ...
) a carbon atom and an atom more
electronegative
Electronegativity, symbolized as , is the tendency for an atom of a given chemical element to attract shared electrons (or electron density) when forming a chemical bond. An atom's electronegativity is affected by both its atomic number and the d ...
than carbon (e.g.
enolate
In organic chemistry, enolates are organic anions derived from the deprotonation of carbonyl () compounds. Rarely isolated, they are widely used as reagents in the synthesis of organic compounds.
Bonding and structure
Enolate anions are electr ...
s) may vary with the nature of the anionic moiety, the metal ion, and possibly the medium. In the absence of direct structural evidence for a carbon–metal bond, such compounds are not considered to be organometallic.
For instance, lithium enolates often contain only Li-O bonds and are not organometallic, while zinc enolates (
Reformatsky reagents) contain both Zn-O and Zn-C bonds, and are organometallic in nature.
Structure and properties
The metal-carbon bond in organometallic compounds is generally highly
covalent
A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atoms ...
. For highly electropositive elements, such as lithium and sodium, the carbon ligand exhibits
carbanionic character, but free carbon-based anions are extremely rare, an example being
cyanide
Cyanide is a naturally occurring, rapidly acting, toxic chemical that can exist in many different forms.
In chemistry, a cyanide () is a chemical compound that contains a functional group. This group, known as the cyano group, consists of ...
.
Most organometallic compounds are solids at room temperature, however some are liquids such as
methylcyclopentadienyl manganese tricarbonyl
Methylcyclopentadienyl manganese tricarbonyl (MMT or MCMT) is an organomanganese compound with the formula (C5H4CH3)Mn(CO)3. Initially marketed as a supplement for use in leaded gasoline, MMT was later used in unleaded gasoline to increase the o ...
, or even
volatile liquids such as
nickel tetracarbonyl
Nickel carbonyl (IUPAC name: tetracarbonylnickel) is a nickel(0) organometallic compound with the formula Ni(CO)4. This colorless liquid is the principal carbonyl of nickel. It is an intermediate in the Mond process for producing very high-pur ...
. Many organometallic compounds are
air sensitive Air sensitivity is a term used, particularly in chemistry, to denote the reactivity of chemical compounds with some constituent of air. Most often, reactions occur with atmospheric oxygen (O2) or water vapor (H2O), although reactions with the other ...
(reactive towards oxygen and moisture), and thus they must be handled under an
inert atmosphere. Some organometallic compounds such as
triethylaluminium
Triethylaluminium is one of the simplest examples of an organoaluminium compound. Despite its name it has the formula Al2( C2H5)6 (abbreviated as Al2Et6 or TEA), as it exists as a dimer. This colorless liquid is pyrophoric. It is an industrially ...
are
pyrophoric
A substance is pyrophoric (from grc-gre, πυροφόρος, , 'fire-bearing') if it ignites spontaneously in air at or below (for gases) or within 5 minutes after coming into contact with air (for liquids and solids). Examples are organolit ...
and will
ignite on contact with air.
Concepts and techniques
As in other areas of chemistry,
electron counting is useful for organizing organometallic chemistry. The
18-electron rule is helpful in predicting the stabilities of organometallic complexes, for example
metal carbonyls
Metal carbonyls are coordination complexes of transition metals with carbon monoxide ligands. Metal carbonyls are useful in organic synthesis and as catalysts or catalyst precursors in homogeneous catalysis, such as hydroformylation and Reppe ch ...
and
metal hydrides
In chemistry, a hydride is formally the anion of hydrogen( H−). The term is applied loosely. At one extreme, all compounds containing covalently bound H atoms are called hydrides: water (H2O) is a hydride of oxygen, ammonia is a hydride of ...
. The 18e rule has two representative electron counting models, ionic and neutral (also known as covalent) ligand models, respectively.
The hapticity of a metal-ligand complex, can influence the electron count.
Hapticity
In coordination chemistry, hapticity is the coordination of a ligand to a metal center via an uninterrupted and contiguous series of atoms. The hapticity of a ligand is described with the Greek letter η ('eta'). For example, η2 describes a l ...
(η, lowercase Greek eta), describes the number of contiguous ligands coordinated to a metal.
For example,
ferrocene
Ferrocene is an organometallic compound with the formula . The molecule is a complex consisting of two cyclopentadienyl rings bound to a central iron atom. It is an orange solid with a camphor-like odor, that sublimes above room temperature, a ...
,
5-C5H5)2Fe">η5-C5H5)2Fe has two
cyclopentadienyl ligands giving a hapticity of 5, where all five carbon atoms of the C
5H
5 ligand bond equally and contribute one electron to the iron center. Ligands that bind non-contiguous atoms are denoted the Greek letter kappa, κ.
Chelating
Chelation is a type of bonding of ions and molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central metal atom. These ligands are ...
κ2-acetate is an example. The
covalent bond classification method The covalent bond classification (CBC) method is also referred to as the LXZ notation. It was published by M. L. H. Green in 1995 as a solution for the need to describe covalent compounds such as organometallic complexes in a way that is not pro ...
identifies three classes of ligands, X,L, and Z; which are based on the electron donating interactions of the ligand. Many organometallic compounds do not follow the 18e rule. The metal atoms in organometallic compounds are frequently described by their
d electron count
The d electron count is a chemistry formalism used to describe the electron configuration of the valence electrons of a transition metal center in a coordination complex. The d electron count is an effective way to understand the geometry and rea ...
and
oxidation state
In chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to different atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. C ...
. These concepts can be used to help predict their reactivity and preferred
geometry
Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is c ...
. Chemical bonding and reactivity in organometallic compounds is often discussed from the perspective of the
isolobal principle
In organometallic chemistry, the isolobal principle (more formally known as the isolobal analogy) is a strategy used to relate the structure of organic and inorganic molecular fragments in order to predict bonding properties of organometallic comp ...
.
A wide variety of physical techniques are used to determine the structure, composition, and properties of organometallic compounds.
X-ray diffraction is a particularly important technique that can locate the positions of atoms within a solid compound, providing a detailed description of its structure. Other techniques like
infrared spectroscopy
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or function ...
and
nuclear magnetic resonance spectroscopy
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuclei. The sample is placed in a magnetic fie ...
are also frequently used to obtain information on the structure and bonding of organometallic compounds.
Ultraviolet-visible spectroscopy is a common technique used to obtain information on the electronic structure of organometallic compounds. It is also used monitor the progress of organometallic reactions, as well as determine their
kinetics
Kinetics ( grc, κίνησις, , kinesis, ''movement'' or ''to move'') may refer to:
Science and medicine
* Kinetics (physics), the study of motion and its causes
** Rigid body kinetics, the study of the motion of rigid bodies
* Chemical ki ...
. The dynamics of organometallic compounds can be studied using
dynamic NMR spectroscopy
In chemistry and molecular physics, fluxional (or non-rigid) molecules are molecules that undergo dynamics such that some or all of their atoms interchange between symmetry-equivalent positions. Because virtually all molecules are fluxional in som ...
. Other notable techniques include
X-ray absorption spectroscopy
X-ray absorption spectroscopy (XAS) is a widely used technique for determining the local geometric and/or electronic structure of matter. The experiment is usually performed at synchrotron radiation facilities, which provide intense and tunabl ...
,
electron paramagnetic resonance spectroscopy
Electron paramagnetic resonance (EPR) or electron spin resonance (ESR) spectroscopy is a method for studying materials that have unpaired electrons. The basic concepts of EPR are analogous to those of nuclear magnetic resonance (NMR), but the spin ...
, and
elemental analysis
Elemental analysis is a process where a sample of some material (e.g., soil, waste or drinking water, bodily fluids, minerals, chemical compounds) is analyzed for its elemental and sometimes isotopic composition. Elemental analysis can be qualita ...
.
Due to their high reactivity towards oxygen and moisture, organometallic compounds often must be handled using
air-free techniques Air-free techniques refer to a range of manipulations in the chemistry laboratory for the handling of compounds that are air-sensitive. These techniques prevent the compounds from reacting with components of air, usually water and oxygen; less com ...
. Air-free handling of organometallic compounds typically requires the use of laboratory apparatuses such as a
glovebox
A glovebox (or glove box) is a sealed container that is designed to allow one to manipulate objects where a separate atmosphere is desired. Built into the sides of the glovebox are gloves arranged in such a way that the user can place their hand ...
or
Schlenk line.
History
Early developments in organometallic chemistry include
Louis Claude Cadet's synthesis of methyl arsenic compounds related to
cacodyl
Cacodyl, also known as dicacodyl or tetramethyldiarsine, (CH3)2As–As(CH3)2, is an organoarsenic compound that constitutes a major part of " Cadet's fuming liquid" (named after the French chemist Louis Claude Cadet de Gassicourt). It is a poisono ...
,
William Christopher Zeise
William Christopher Zeise (15 October 1789 – 12 November 1847) was a Danish organic chemist. He is best known for synthesising one of the first organometallic compounds, named Zeise's salt in his honour. He also performed pioneering studi ...
's
platinum-ethylene complex,
Edward Frankland
Sir Edward Frankland, (18 January 18259 August 1899) was an English chemist. He was one of the originators of organometallic chemistry and introduced the concept of combining power or valence. An expert in water quality and analysis, he was ...
's discovery of
diethyl- and
dimethylzinc
Dimethylzinc, also known as Zinc methyl, DMZ, or DMZn is a colorless volatile liquid Zn(CH3)2, formed by the action of methyl iodide on zinc at elevated temperature or on zinc sodium alloy.
:2Zn + 2CH3I → Zn(CH3)2 + ZnI2
The sodium assists the ...
,
Ludwig Mond
Ludwig Mond FRS (7 March 1839 – 11 December 1909) was a German-born, British chemist and industrialist. He discovered an important, previously unknown, class of compounds called metal carbonyls.
Education and career
Ludwig Mond was born ...
's discovery of
Ni(CO)4, and
Victor Grignard
Francois Auguste Victor Grignard (6 May 1871 – 13 December 1935) was a French chemist who won the Nobel Prize for his discovery of the eponymously named Grignard reagent and Grignard reaction, both of which are important in the formation of c ...
's organomagnesium compounds. (Though not always acknowledged as an organometallic compound,
Prussian blue
Prussian blue (also known as Berlin blue, Brandenburg blue or, in painting, Parisian or Paris blue) is a dark blue pigment produced by oxidation of ferrous ferrocyanide salts. It has the chemical formula Fe CN)">Cyanide.html" ;"title="e(Cyani ...
, a mixed-valence iron-cyanide complex, was first prepared in 1706 by paint maker
Johann Jacob Diesbach as the first
coordination polymer and synthetic material containing a metal-carbon bond.) The abundant and diverse products from coal and petroleum led to
Ziegler–Natta,
Fischer–Tropsch,
hydroformylation
Hydroformylation, also known as oxo synthesis or oxo process, is an industrial process for the production of aldehydes from alkenes. This chemical reaction entails the net addition of a formyl group (CHO) and a hydrogen atom to a carbon-carbon d ...
catalysis which employ CO, H
2, and alkenes as feedstocks and ligands.
Recognition of organometallic chemistry as a distinct subfield culminated in the Nobel Prizes to
Ernst Fischer and
Geoffrey Wilkinson
Sir Geoffrey Wilkinson FRS (14 July 1921 – 26 September 1996) was a Nobel laureate English chemist who pioneered inorganic chemistry and homogeneous transition metal catalysis.
Education and early life
Wilkinson was born at Springside, Todm ...
for work on
metallocene
A metallocene is a compound typically consisting of two cyclopentadienyl anions (, abbreviated Cp) bound to a metal center (M) in the oxidation state II, with the resulting general formula Closely related to the metallocenes are the metallocene d ...
s. In 2005,
Yves Chauvin
Yves Chauvin (; 10 October 1930 – 27 January 2015) was a French chemist and Nobel Prize laureate. He was honorary research director at the ''Institut français du pétrole'' and a member of the French Academy of Science. He was known for his work ...
,
Robert H. Grubbs
Robert Howard Grubbs ForMemRS (February 27, 1942 – December 19, 2021) was an American chemist and the Victor and Elizabeth Atkins Professor of Chemistry at the California Institute of Technology in Pasadena, California. He was a co-recipient ...
and
Richard R. Schrock shared the Nobel Prize for metal-catalyzed
olefin metathesis
Olefin metathesis is an organic reaction that entails the redistribution of fragments of alkenes (olefins) by the scission and regeneration of carbon-carbon double bonds. Because of the relative simplicity of olefin metathesis, it often create ...
.
Organometallic chemistry timeline
* 1760
Louis Claude Cadet de Gassicourt
Louis Claude Cadet de Gassicourt (24 July 1731 – 17 October 1799) was a French chemist who synthesised the first organometalic compound.
He obtained a red liquid by the reaction of potassium acetate with arsenic trioxide. This liquid is ...
investigates inks based on
cobalt
Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, p ...
salts and isolates
cacodyl
Cacodyl, also known as dicacodyl or tetramethyldiarsine, (CH3)2As–As(CH3)2, is an organoarsenic compound that constitutes a major part of " Cadet's fuming liquid" (named after the French chemist Louis Claude Cadet de Gassicourt). It is a poisono ...
from cobalt mineral containing
arsenic
Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but ...
* 1827
William Christopher Zeise
William Christopher Zeise (15 October 1789 – 12 November 1847) was a Danish organic chemist. He is best known for synthesising one of the first organometallic compounds, named Zeise's salt in his honour. He also performed pioneering studi ...
produces
Zeise's salt
Zeise's salt, potassium trichloro(ethylene)platinate(II), is the chemical compound with the formula K platinum">PtCl3(C2H4).html" ;"title="platinum.html" ;"title="/nowiki>PtCl3(C2H4)">platinum.html"_;"title="/nowiki>platinum">PtCl3(C2H4)H2O.__Th ...
; the first
platinum
Platinum is a chemical element with the symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish , a diminutive of "silver".
Pla ...
/
olefin complex
* 1848
Edward Frankland
Sir Edward Frankland, (18 January 18259 August 1899) was an English chemist. He was one of the originators of organometallic chemistry and introduced the concept of combining power or valence. An expert in water quality and analysis, he was ...
discovers
diethylzinc
Diethylzinc (C2H5)2Zn, or DEZ, is a highly pyrophoric and reactive organozinc compound consisting of a zinc center bound to two ethyl groups. This colourless liquid is an important reagent in organic chemistry. It is available commercially as a ...
* 1863
Charles Friedel
Charles Friedel (; 12 March 1832 – 20 April 1899) was a French chemist and mineralogist.
Life
A native of Strasbourg, France, he was a student of Louis Pasteur at the Sorbonne. In 1876, he became a professor of chemistry and mineralogy at t ...
and
James Crafts
James Mason Crafts (March 8, 1839 – June 20, 1917) was an American chemist, mostly known for developing the Friedel–Crafts alkylation and acylation reactions with Charles Friedel in 1876.
Biography
James Crafts, the son of Royal Altamo ...
prepare organochlorosilanes
* 1890
Ludwig Mond
Ludwig Mond FRS (7 March 1839 – 11 December 1909) was a German-born, British chemist and industrialist. He discovered an important, previously unknown, class of compounds called metal carbonyls.
Education and career
Ludwig Mond was born ...
discovers
nickel carbonyl
Nickel carbonyl (IUPAC name: tetracarbonylnickel) is a nickel(0) organometallic compound with the formula Ni(CO)4. This colorless liquid is the principal carbonyl of nickel. It is an intermediate in the Mond process for producing very high-pu ...
* 1899 Introduction of
Grignard reaction
The Grignard reaction () is an organometallic chemical reaction in which alkyl, allyl, vinyl, or aryl-magnesium halides (Grignard reagent) is added to a carbonyl group in an aldehyde or ketone. This reaction is important for the formation of ...
* 1899
John Ulric Nef discovers
alkynylation using sodium
acetylide
In organometallic chemistry, acetylide refers to chemical compounds with the chemical formulas and , where M is a metal. The term is used loosely and can refer to substituted acetylides having the general structure (where R is an organic side c ...
s.
* 1900
Paul Sabatier Paul Sabatier may refer to:
*Paul Sabatier (chemist) (1854–1941), French chemist and Nobel Prize winner
*Paul Sabatier (theologian)
Charles Paul Marie Sabatier (3 or 9 August 1858 – 5 March 1928), was a French clergyman and historian who prod ...
works on
hydrogenation
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organ ...
organic compounds with metal catalysts. Hydrogenation of
fat
In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.
The term often refers specifically to triglycerides (triple est ...
s kicks off advances in
food industry, see
margarine
* 1909
Paul Ehrlich
Paul Ehrlich (; 14 March 1854 – 20 August 1915) was a Nobel Prize-winning German physician and scientist who worked in the fields of hematology, immunology, and antimicrobial chemotherapy. Among his foremost achievements were finding a cure ...
introduces
Salvarsan
Arsphenamine, also known as Salvarsan or compound 606, is a drug that was introduced at the beginning of the 1910s as the first effective treatment for syphilis, relapsing fever, and African trypanosomiasis.
This organoarsenic compound was the fi ...
for the treatment of syphilis, an early arsenic based organometallic compound
* 1912
Nobel Prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
Victor Grignard
Francois Auguste Victor Grignard (6 May 1871 – 13 December 1935) was a French chemist who won the Nobel Prize for his discovery of the eponymously named Grignard reagent and Grignard reaction, both of which are important in the formation of c ...
and
Paul Sabatier Paul Sabatier may refer to:
*Paul Sabatier (chemist) (1854–1941), French chemist and Nobel Prize winner
*Paul Sabatier (theologian)
Charles Paul Marie Sabatier (3 or 9 August 1858 – 5 March 1928), was a French clergyman and historian who prod ...
* 1930
Henry Gilman
Henry Gilman (May 9, 1893 – November 7, 1986) was an American organic chemist known as the father of organometallic chemistry, the field within which his most notable work was done. He discovered the Gilman reagent, which bears his name.
Earl ...
works on lithium cuprates, see
Gilman reagent
A Gilman reagent is a lithium and copper ( diorganocopper) reagent compound, R2CuLi, where R is an alkyl or aryl. These reagents are useful because, unlike related Grignard reagents and organolithium reagents, they react with organic halides to ...
* 1951
Walter Hieber
Walter Hieber (18 December 1895 – 29 November 1976) was an inorganic chemist, known as the father of metal carbonyl chemistry. He was born 18 December 1895 and died 29 November 1976. Hieber's father was Johannes Hieber, an influential evangel ...
was awarded the
Alfred Stock
Alfred Stock (July 16, 1876 – August 12, 1946) was a German inorganic chemist. He did pioneering research on the hydrides of boron and silicon, coordination chemistry, mercury, and mercury poisoning. The German Chemical Society's Alfred-Stoc ...
prize for his work with
metal carbonyl
Metal carbonyls are coordination complexes of transition metals with carbon monoxide ligands. Metal carbonyls are useful in organic synthesis and as catalysts or catalyst precursors in homogeneous catalysis, such as hydroformylation and Reppe c ...
chemistry.
* 1951
Ferrocene
Ferrocene is an organometallic compound with the formula . The molecule is a complex consisting of two cyclopentadienyl rings bound to a central iron atom. It is an orange solid with a camphor-like odor, that sublimes above room temperature, a ...
is discovered
* 1956
Dorothy Crawfoot Hodgkin determines the structure of
vitamin B12, the first biomolecule found to contain a metal-carbon bond, see
bioorganometallic chemistry
Bioorganometallic chemistry is the study of biologically active molecules that contain carbon directly bonded to metals or metalloids. The importance of main-group and transition-metal centers has long been recognized as important to the function o ...
* 1963
Nobel prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
for
Karl Ziegler
Karl Waldemar Ziegler (26 November 1898 – 12 August 1973) was a German chemist who won the Nobel Prize in Chemistry in 1963, with Giulio Natta, for work on polymers. The Nobel Committee recognized his "excellent work on organometallic compound ...
and
Giulio Natta
Giulio Natta (26 February 1903 – 2 May 1979) was an Italian chemical engineer and Nobel laureate. He won a Nobel Prize in Chemistry in 1963 with Karl Ziegler for work on high polymers. He also received a Lomonosov Gold Medal in 1969.
Biograph ...
on
Ziegler–Natta catalyst A Ziegler–Natta catalyst, named after Karl Ziegler and Giulio Natta, is a catalyst used in the synthesis of polymers of 1-alkenes ( alpha-olefins). Two broad classes of Ziegler–Natta catalysts are employed, distinguished by their solubility:
* ...
* 1965 Discovery of
cyclobutadieneiron tricarbonyl
Cyclobutadieneiron tricarbonyl is an organoiron compound with the formula Fe(C4H4)(CO)3. It is a yellow solid that is soluble in organic solvents. It has been used in organic chemistry as a precursor for cyclobutadiene, which is an elusive specie ...
* 1968
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 ...
is developed
* 1973
Nobel prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
Geoffrey Wilkinson
Sir Geoffrey Wilkinson FRS (14 July 1921 – 26 September 1996) was a Nobel laureate English chemist who pioneered inorganic chemistry and homogeneous transition metal catalysis.
Education and early life
Wilkinson was born at Springside, Todm ...
and
Ernst Otto Fischer
Ernst Otto Fischer (; 10 November 1918 – 23 July 2007) was a German chemist who won the Nobel Prize for pioneering work in the area of organometallic chemistry.
Early life
He was born in Solln, a borough of Munich. His parents were Karl T. Fi ...
on
sandwich compound
In organometallic chemistry, a sandwich compound is a chemical compound featuring a metal bound by haptic, covalent bonds to two arene (ring) ligands. The arenes have the formula , substituted derivatives (for example ) and heterocyclic deriv ...
s
* 1981
Nobel prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
Roald Hoffmann
Roald Hoffmann (born Roald Safran; July 18, 1937) is a Polish-American theoretical chemist who won the 1981 Nobel Prize in Chemistry. He has also published plays and poetry. He is the Frank H. T. Rhodes Professor of Humane Letters, Emeritus, at ...
and
Kenichi Fukui
was a Japanese chemist, known as the first Asian person to be awarded the Nobel Prize in Chemistry.
Fukui was co-recipient of the 1981 Nobel Prize in Chemistry with Roald Hoffmann, for their independent investigations into the mechanisms of che ...
for creation of the Woodward-Hoffman Rules
* 2001
Nobel prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
W. S. Knowles,
R. Noyori and
Karl Barry Sharpless
Karl Barry Sharpless (born April 28, 1941) is an American chemist and a two-time Nobel laureate in Chemistry known for his work on stereoselective reactions and click chemistry.
Sharpless was awarded half of the 2001 Nobel Prize in Chemistry " ...
for asymmetric hydrogenation
* 2005
Nobel prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
Yves Chauvin
Yves Chauvin (; 10 October 1930 – 27 January 2015) was a French chemist and Nobel Prize laureate. He was honorary research director at the ''Institut français du pétrole'' and a member of the French Academy of Science. He was known for his work ...
,
Robert Grubbs
Robert Howard Grubbs ForMemRS (February 27, 1942 – December 19, 2021) was an American chemist and the Victor and Elizabeth Atkins Professor of Chemistry at the California Institute of Technology in Pasadena, California. He was a co-recipient ...
, and
Richard Schrock
Richard Royce Schrock (born January 4, 1945) is an American chemist and Nobel laureate recognized for his contributions to the olefin metathesis reaction used in organic chemistry.
Education
Born in Berne, Indiana, Schrock went to Mission Bay ...
on metal-catalyzed
alkene metathesis
Olefin metathesis is an organic reaction that entails the redistribution of fragments of alkenes (olefins) by the scission and regeneration of carbon-carbon double bonds. Because of the relative simplicity of olefin metathesis, it often create ...
* 2010
Nobel prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
Richard F. Heck,
Ei-ichi Negishi
was a Japanese chemist who was best known for his discovery of the Negishi coupling. He spent most of his career at Purdue University in the United States, where he was the Herbert C. Brown Distinguished Professor and the director of the Negi ...
,
Akira Suzuki for palladium catalyzed cross coupling reactions
Scope
Subspecialty areas of organometallic chemistry include:
*
Period 2 element
A period 2 element is one of the chemical elements in the second row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of th ...
s:
organolithium chemistry,
organoberyllium chemistry,
organoborane chemistry
*
Period 3 element
A period 3 element is one of the chemical elements in the third row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the ele ...
s:
organosodium chemistry
Organosodium chemistry is the chemistry of organometallic compounds containing a carbon to sodium chemical bond. The application of organosodium compounds in chemistry is limited in part due to competition from organolithium compounds, which are ...
,
organomagnesium chemistry Magnesium anthracenide with three thf ligands. Group 2 organometallic chemistry refers to the chemistry of compounds containing carbon bonded to any group 2 element. By far the most common group 2 organometallic compounds are the magnesium-contain ...
,
organoaluminium chemistry,
organosilicon chemistry
Organosilicon compounds are organometallic compounds containing carbon–silicon bonds. Organosilicon chemistry is the corresponding science of their preparation and properties. Most organosilicon compounds are similar to the ordinary organic c ...
*
Period 4 element
A period 4 element is one of the chemical elements in the fourth row (or ''period'') of the periodic table of the elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements ...
s:
organocalcium chemistry,
organoscandium chemistry,
organotitanium chemistry,
organovanadium chemistry,
organochromium chemistry Organochromium chemistry is a branch of organometallic chemistry that deals with organic compounds containing a chromium to carbon bond and their reactions. The field is of some relevance to organic synthesis. The relevant oxidation states for organ ...
,
organomanganese chemistry,
organoiron chemistry
Organoiron chemistry is the chemistry of iron compounds containing a carbon-to-iron chemical bond. Organoiron compounds are relevant in organic synthesis as reagents such as iron pentacarbonyl, diiron nonacarbonyl and disodium tetracarbonylferrate ...
,
organocobalt chemistry
Organocobalt chemistry is the chemistry of organometallic compounds containing a carbon to cobalt chemical bond. Organocobalt compounds are involved in several organic reactions and the important biomolecule vitamin B12 has a cobalt-carbon bond. ...
,
organonickel chemistry,
organocopper chemistry
Organocopper compounds is the chemistry of organometallic compounds containing a carbon to copper chemical bond. Organocopper chemistry is the study of organocopper compounds describing their physical properties, synthesis and reactions. They a ...
,
organozinc chemistry,
organogallium chemistry,
organogermanium chemistry Organogermanium compounds are organometallic compounds containing a carbon to germanium or hydrogen to germanium chemical bond. Organogermanium chemistry is the corresponding chemical science. Germanium shares group 14 in the periodic table with s ...
,
organoarsenic chemistry
Organoarsenic chemistry is the chemistry of compounds containing a chemical bond between arsenic and carbon. A few organoarsenic compounds, also called "organoarsenicals," are produced industrially with uses as insecticides, herbicides, and fungic ...
,
organoselenium chemistry
Organoselenium compounds (or seleno-organic) are chemical compounds containing carbon-to-selenium chemical bonds. Organoselenium chemistry is the corresponding science exploring their properties and reactivity. Selenium belongs with oxygen and sulf ...
*
Period 5 element
The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements with si ...
s:
organoyttrium chemistry
Organoyttrium chemistry is the study of compounds containing carbon-yttrium
Yttrium is a chemical element with the symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and has often be ...
,
organozirconium chemistry
Organozirconium chemistry is the science of exploring the properties, structure, and reactivity of organozirconium compounds, which are organometallic compounds containing chemical bonds between carbon and zirconium. Organozirconium compounds have ...
,
organoniobium chemistry,
organomolybdenum chemistry,
organoruthenium chemistry Organoruthenium chemistry is the chemistry of organometallic compounds containing a carbon to ruthenium chemical bond. Several organoruthenium catalysts are of commercial interest and organoruthenium compounds have been considered for cancer therap ...
,
organorhodium chemistry Organorhodium chemistry is the chemistry of organometallic compounds containing a rhodium-carbon chemical bond, and the study of rhodium and rhodium compounds as catalysts in organic reactions.
Stable organorhodium compounds and transient organorho ...
,
organopalladium chemistry Organopalladium chemistry is a branch of organometallic chemistry that deals with organic palladium compounds and their reactions. Palladium is often used as a catalyst in the reduction of alkenes and alkynes with hydrogen. This process involves the ...
,
organosilver chemistry
Organosilver chemistry is the study of organometallic compounds containing a carbon to silver chemical bond. The theme is less developed than organocopper chemistry.
The first attempts in organosilver were recorded by Buckton in 1859 and by J. A ...
,
organocadmium chemistry,
organoindium chemistry Organoindium chemistry is the chemistry of compounds containing In-C bonds. The main application of organoindium chemistry is in the preparation of semiconducting components for microelectronic applications. The area is also of some interest in orga ...
,
organotin chemistry
Organotin compounds or stannanes are chemical compounds based on tin with hydrocarbon substituents. Organotin chemistry is part of the wider field of organometallic chemistry. The first organotin compound was diethyltin diiodide (), discovered b ...
,
organoantimony chemistry Organoantimony chemistry is the chemistry of compounds containing a carbon to antimony (Sb) chemical bond. Relevant oxidation states are Sb(V) and Sb(III). The toxicity of antimony limits practical application in organic chemistry.
Organoantimony ...
,
organotellurium chemistry Organotellurium chemistry describes the synthesis and properties of chemical compounds containing a carbon-tellurium chemical bond. Organotellurium chemistry is a lightly studied area, in part because of the few applications.
Functional groups
The ...
*
Period 6 element
A period 6 element is one of the chemical elements in the sixth row (or ''Periodic table period, period'') of the periodic table, periodic table of the elements, including the lanthanides. The periodic table is laid out in rows to illustrate recu ...
s:
organolanthanide chemistry,
organocerium chemistry,
organotantalum chemistry,
organorhenium chemistry,
organoosmium chemistry,
organoiridium chemistry,
organoplatinum chemistry,
organogold chemistry
Organogold chemistry is the study of compounds containing gold–carbon bonds. They are studied in academic research, but have not received widespread use otherwise. The dominant oxidation states for organogold compounds are I with coordination num ...
,
organomercury chemistry,
organothallium chemistry Organogallium chemistry is the chemistry of organometallic compounds containing a carbon to gallium (Ga) chemical bond. Despite their high toxicity , organogallium compounds have some use in organic synthesis. The compound trimethylgallium is of som ...
,
organolead chemistry Organolead compounds are chemical compounds containing a chemical bond between carbon and lead. Organolead chemistry is the corresponding science. The first organolead compound was hexaethyldilead (Pb2(C2H5)6), first synthesized in 1858.''Main Grou ...
,
organobismuth chemistry
Organobismuth chemistry is the chemistry of organometallic compounds containing a carbon to bismuth chemical bond. Applications are few. The main bismuth oxidation states are Bi(III) and Bi(V) as in all higher group 15 elements. The energy of a b ...
,
organopolonium chemistry
Organopolonium chemistry describes the synthesis and properties of chemical compounds containing a carbon to polonium chemical bond.
As polonium is a highly radioactive element (its most commonly used isotope, 210Po, has a half-life of about 138&n ...
*
Period 7 element
A period 7 element is one of the chemical elements in the seventh row (or '' period'') of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of t ...
s:
organoactinide chemistry
Organoactinide chemistry is the science exploring the properties, structure and reactivity of organoactinide compounds, which are organometallic compounds containing a carbon to actinide chemical bond.
Like most organometallic compounds, the orga ...
,
organouranium chemistry,
organoneptunium chemistry Organoneptunium chemistry is the chemical science exploring the properties, structure and reactivity of organoneptunium compounds, which are organometallic compounds containing a carbon to neptunium chemical bond. Several such compounds exist even t ...
Industrial applications
Organometallic compounds find wide use in commercial reactions, both as
homogenous catalysts and as
stoichiometric reagents. For instance,
organolithium
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 ...
,
organomagnesium Magnesium anthracenide with three thf ligands. Group 2 organometallic chemistry refers to the chemistry of compounds containing carbon bonded to any group 2 element. By far the most common group 2 organometallic compounds are the magnesium-contain ...
, and
organoaluminium compound
Organoaluminium chemistry is the study of compounds containing bonds between carbon and aluminium. It is one of the major themes within organometallic chemistry. Illustrative organoaluminium compounds are the dimer trimethylaluminium, the monomer ...
s, examples of which are highly basic and highly reducing, are useful stoichiometrically but also catalyze many polymerization reactions.
Almost all processes involving carbon monoxide rely on catalysts, notable examples being described as
carbonylation
Carbonylation refers to reactions that introduce carbon monoxide into organic and inorganic substrates. Carbon monoxide is abundantly available and conveniently reactive, so it is widely used as a reactant in industrial chemistry. The term carbony ...
s.
The production of acetic acid from methanol and carbon monoxide is catalyzed via
metal carbonyl complex
Metal carbonyls are coordination complexes of transition metals with carbon monoxide ligands. Metal carbonyls are useful in organic synthesis and as catalysts or catalyst precursors in homogeneous catalysis, such as hydroformylation and Reppe c ...
es in the
Monsanto process
The Monsanto process is an industrial method for the manufacture of acetic acid by catalytic carbonylation of methanol. The Monsanto process has largely been supplanted by the Cativa process, a similar iridium-based process developed by BP Chemic ...
and
Cativa process
The Cativa process is a method for the production of acetic acid by the carbonylation of methanol. The technology, which is similar to the Monsanto process, was developed by BP Chemicals and is under license by BP Plc. The process is based on an ...
. Most synthetic aldehydes are produced via
hydroformylation
Hydroformylation, also known as oxo synthesis or oxo process, is an industrial process for the production of aldehydes from alkenes. This chemical reaction entails the net addition of a formyl group (CHO) and a hydrogen atom to a carbon-carbon d ...
. The bulk of the synthetic alcohols, at least those larger than ethanol, are produced by
hydrogenation
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organ ...
of hydroformylation-derived aldehydes. Similarly, the
Wacker process
The Wacker process or the Hoechst-Wacker process (named after the chemical companies of the same name) refers to the oxidation of ethylene to acetaldehyde in the presence of palladium(II) chloride as the catalyst. This chemical reaction was one of ...
is used in the oxidation of
ethylene to
acetaldehyde.
![ConstrainedGeomCmpx](https://upload.wikimedia.org/wikipedia/commons/2/22/ConstrainedGeomCmpx.png)
Almost all industrial processes involving
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 ...
-derived polymers rely on organometallic catalysts. The world's polyethylene and polypropylene are produced via both
heterogeneously via
Ziegler–Natta catalysis and homogeneously, e.g., via
constrained geometry catalysts.
Most processes involving hydrogen rely on metal-based catalysts. Whereas bulk
hydrogenation
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organ ...
s (e.g., margarine production) rely on heterogeneous catalysts, for the production of fine chemicals such hydrogenations rely on soluble (homogenous) organometallic complexes or involve organometallic intermediates.
Organometallic complexes allow these hydrogenations to be effected asymmetrically.
Many
semiconductors are produced from
trimethylgallium
Trimethylgallium, often abbreviated to TMG or TMGa, is the organogallium compound with the formula Ga(CH3)3. It is a colorless, pyrophoric liquid. Unlike trimethylaluminium, TMG adopts a monomeric structure. When examined in detail, the monomeric ...
,
trimethylindium
Trimethylindium, often abbreviated to TMI or TMIn, is the organoindium compound with the formula In(CH3)3. It is a colorless, pyrophoric solid. Unlike trimethylaluminium, but akin to trimethylgallium, TMI is monomeric.
Preparation
TMI is prepared ...
,
trimethylaluminium
Trimethylaluminium is one of the simplest examples of an organoaluminium compound. Despite its name it has the formula Al2( CH3)6 (abbreviated as Al2Me6 or TMA), as it exists as a dimer. This colorless liquid is pyrophoric. It is an industriall ...
, and
trimethylantimony. These volatile compounds are decomposed along with
ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous wa ...
,
arsine
Arsine (IUPAC name: arsane) is an inorganic compound with the formula As H3. This flammable, pyrophoric, and highly toxic pnictogen hydride gas is one of the simplest compounds of arsenic. Despite its lethality, it finds some applications in ...
,
phosphine
Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting ...
and related hydrides on a heated substrate via
metalorganic vapor phase epitaxy (MOVPE) process in the production of
light-emitting diode
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (co ...
s (LEDs).
Organometallic reactions
Organometallic compounds undergo several important reactions:
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associative and
dissociative substitution
In chemistry, dissociative substitution describes a Chemical reaction, reaction pathway by which Chemical compound, compounds interchange ligands. The term is typically applied to Coordination chemistry, coordination and Organometallic chemistry ...
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oxidative addition
Oxidative addition and reductive elimination are two important and related classes of reactions in organometallic chemistry. Oxidative addition is a process that increases both the oxidation state and coordination number of a metal centre. Oxid ...
and
reductive elimination
Reductive elimination is an elementary step in organometallic chemistry in which the oxidation state of the metal center decreases while forming a new covalent bond between two ligands. It is the microscopic reverse of oxidative addition, and is ...
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transmetalation
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migratory insertion
In organometallic chemistry, a migratory insertion is a type of reaction wherein two ligands on a metal complex combine. It is a subset of reactions that very closely resembles the insertion reactions, and both are differentiated by the mechanis ...
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β-hydride elimination
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electron transfer
Electron transfer (ET) occurs when an electron relocates from an atom or molecule to another such chemical entity. ET is a mechanistic description of certain kinds of redox reactions involving transfer of electrons.
Electrochemical processes ar ...
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carbon-hydrogen bond activation
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carbometalation
A carbometalation is any reaction where a carbon-metal bond reacts with a carbon-carbon π-bond to produce a new carbon-carbon σ-bond and a carbon-metal σ-bond. The resulting carbon-metal bond can undergo further carbometallation reactions (oli ...
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hydrometalation Hydrometalation (hydrometallation) is a type of chemical reaction in organometallic chemistry in which a chemical compound with a hydrogen to metal bond (M-H, metal hydride) adds to compounds with an unsaturated bond like an alkene (RC=CR) forming ...
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cyclometalation
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nucleophilic abstraction
Nucleophilic abstraction is a type of an organometallic reaction which can be defined as a nucleophilic attack on a ligand which causes part or all of the original ligand to be removed from the metal along with the nucleophile.Spessard, Gary; Mie ...
The synthesis of many organic molecules are facilitated by organometallic complexes.
Sigma-bond metathesis In organometallic chemistry, sigma-bond metathesis is a chemical reaction wherein a metal-ligand sigma bond undergoes metathesis (exchange of parts) with the sigma bond in some reagent. The reaction is illustrated by the exchange of lutetium(III) ...
is a synthetic method for forming new carbon-carbon
sigma bond
In chemistry, sigma bonds (σ bonds) are the strongest type of covalent chemical bond. They are formed by head-on overlapping between atomic orbitals. Sigma bonding is most simply defined for diatomic molecules using the language and tools of s ...
s. Sigma-bond metathesis is typically used with early transition-metal complexes that are in their highest oxidation state. Using transition-metals that are in their highest oxidation state prevents other reactions from occurring, such as
oxidative addition
Oxidative addition and reductive elimination are two important and related classes of reactions in organometallic chemistry. Oxidative addition is a process that increases both the oxidation state and coordination number of a metal centre. Oxid ...
. In addition to sigma-bond metathesis,
olefin metathesis
Olefin metathesis is an organic reaction that entails the redistribution of fragments of alkenes (olefins) by the scission and regeneration of carbon-carbon double bonds. Because of the relative simplicity of olefin metathesis, it often create ...
is used to synthesize various carbon-carbon
pi bond
In chemistry, pi bonds (π bonds) are covalent chemical bonds, in each of which two lobes of an orbital on one atom overlap with two lobes of an orbital on another atom, and in which this overlap occurs laterally. Each of these atomic orbitals ...
s. Neither sigma-bond metathesis or olefin metathesis change the oxidation state of the metal. Many other methods are used to form new carbon-carbon bonds, including
beta-hydride elimination
β-Hydride elimination is a reaction in which an alkyl group bonded to a metal centre is converted into the corresponding metal-bonded hydride and an alkene. The alkyl must have hydrogens on the β-carbon. For instance butyl groups can undergo th ...
and
insertion reaction
An insertion reaction is a chemical reaction where one chemical entity (a molecule or molecular fragment) interposes itself into an existing bond of typically a second chemical entity ''e.g.'':
: + \longrightarrow
The term only refers to the ...
s.
Catalysis
Organometallic complexes are commonly used in catalysis. Major industrial processes include
hydrogenation
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organ ...
,
hydrosilylation Hydrosilylation, also called catalytic hydrosilation, describes the addition of Si-H bonds across unsaturated bonds."Hydrosilylation A Comprehensive Review on Recent Advances" B. Marciniec (ed.), Advances in Silicon Science, Springer Science, 2009 ...
,
hydrocyanation
In organic chemistry, hydrocyanation is a process for conversion of alkenes to nitriles. The reaction involves the addition of hydrogen cyanide and requires a catalyst. This conversion is conducted on an industrial scale for the production of ...
,
olefin metathesis
Olefin metathesis is an organic reaction that entails the redistribution of fragments of alkenes (olefins) by the scission and regeneration of carbon-carbon double bonds. Because of the relative simplicity of olefin metathesis, it often create ...
,
alkene polymerization
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 ...
,
alkene oligomerization,
hydrocarboxylation
Carbonylation refers to reactions that introduce carbon monoxide into organic and inorganic substrates. Carbon monoxide is abundantly available and conveniently reactive, so it is widely used as a reactant in industrial chemistry. The term carbo ...
,
methanol carbonylation
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...
, and
hydroformylation
Hydroformylation, also known as oxo synthesis or oxo process, is an industrial process for the production of aldehydes from alkenes. This chemical reaction entails the net addition of a formyl group (CHO) and a hydrogen atom to a carbon-carbon d ...
. Organometallic intermediates are also invoked in many
heterogeneous catalysis
In chemistry, heterogeneous catalysis is catalysis where the phase of catalysts differs from that of the reactants or products. The process contrasts with homogeneous catalysis where the reactants, products and catalyst exist in the same phase. ...
processes, analogous to those listed above. Additionally, organometallic intermediates are assumed for
Fischer–Tropsch process
The Fischer–Tropsch process is a collection of chemical reactions that converts a mixture of carbon monoxide and hydrogen, known as syngas, into liquid hydrocarbons. These reactions occur in the presence of metal catalysts, typically at temperatu ...
.
Organometallic complexes are commonly used in small-scale fine chemical synthesis as well, especially in
cross-coupling reaction
In organic chemistry, a cross-coupling reaction is a reaction where two fragments are joined together with the aid of a metal catalyst. In one important reaction type, a main group organometallic compound of the type R-M (R = organic fragment, M = ...
s that form carbon-carbon bonds, e.g.
Suzuki-Miyaura coupling,
Buchwald-Hartwig amination for producing aryl amines from aryl halides, and
Sonogashira coupling
The Sonogashira reaction is a cross-coupling reaction used in organic synthesis to form carbon–carbon bonds. It employs a palladium catalyst as well as copper co-catalyst to form a carbon–carbon bond between a terminal alkyne and an aryl or v ...
, etc.
Environmental concerns
![Roxarsone](https://upload.wikimedia.org/wikipedia/commons/2/20/Roxarsone.png)
Natural and contaminant organometallic compounds are found in the environment. Some that are remnants of human use, such as organolead and organomercury compounds, are toxicity hazards.
Tetraethyllead
Tetraethyllead (commonly styled tetraethyl lead), abbreviated TEL, is an organolead compound with the formula Pb( C2H5)4. It is a fuel additive, first being mixed with gasoline beginning in the 1920s as a patented octane rating booster that ...
was prepared for use as a
gasoline
Gasoline (; ) or petrol (; ) (see ) is a transparent, petroleum-derived flammable liquid that is used primarily as a fuel in most spark-ignited internal combustion engines (also known as petrol engines). It consists mostly of organic co ...
additive but has fallen into disuse because of lead's toxicity. Its replacements are other organometallic compounds, such as
ferrocene
Ferrocene is an organometallic compound with the formula . The molecule is a complex consisting of two cyclopentadienyl rings bound to a central iron atom. It is an orange solid with a camphor-like odor, that sublimes above room temperature, a ...
and
methylcyclopentadienyl manganese tricarbonyl
Methylcyclopentadienyl manganese tricarbonyl (MMT or MCMT) is an organomanganese compound with the formula (C5H4CH3)Mn(CO)3. Initially marketed as a supplement for use in leaded gasoline, MMT was later used in unleaded gasoline to increase the o ...
(MMT).
The
organoarsenic compound
Organoarsenic chemistry is the chemistry of compounds containing a chemical bond between arsenic and carbon. A few organoarsenic compounds, also called "organoarsenicals," are produced industrially with uses as insecticides, herbicides, and fu ...
roxarsone is a controversial animal feed additive. In 2006, approximately one million kilograms of it were produced in the U.S alone.
Organotin compounds
Organotin compounds or stannanes are chemical compounds based on tin with hydrocarbon substituents. Organotin chemistry is part of the wider field of organometallic chemistry. The first organotin compound was diethyltin diiodide (), discovered ...
were once widely used in
anti-fouling paint
Anti-fouling paint is a specialized category of coatings applied as the outer (outboard) layer to the hull of a ship or boat, to slow the growth of and facilitate detachment of subaquatic organisms that attach to the hull and can affect a vess ...
s but have since been banned due to environmental concerns.
See also
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Bioorganometallic chemistry
Bioorganometallic chemistry is the study of biologically active molecules that contain carbon directly bonded to metals or metalloids. The importance of main-group and transition-metal centers has long been recognized as important to the function o ...
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Metal carbon dioxide complex
References
Sources
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External links
MIT OpenCourseWare: Organometallic ChemistryRob Toreki's Organometallic HyperTextbook web listing of US chemists who specialize in organometallic chemistry
{{DEFAULTSORT:Organometallic Chemistry