Organovanadium chemistry is the

chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...

organometallic compounds Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and so ...

containing 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 ...

vanadium Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer ( pas ...

(V)

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 ...

. Organovanadium compounds find only minor use as reagents in

organic synthesis Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one o ...

but are significant for

polymer chemistry Polymer chemistry is a sub-discipline of chemistry that focuses on the structures of chemicals, chemical synthesis, and chemical and physical properties of polymers and macromolecules. The principles and methods used within polymer chemistry are ...

catalysts 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 ...

Oxidation states 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. Co ...

for vanadium are +2, +3, +4 and +5. Low valency vanadium is usually stabilized with

carbonyl 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 ...

ligands. Oxo derivatives are relatively common, unlike the organic complexes of neighboring elements.

Compound classes

Carbonyls

Vanadium carbonyl Vanadium hexacarbonyl is the inorganic compound with the formula V(CO)6. It is a blue-black volatile solid. This highly reactive species is noteworthy from theoretical perspectives as a rare isolable homoleptic metal carbonyl that is paramagneti ...

can be prepared by reductive

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 carbon ...

of vanadium salts: :4 Na + VCl₃ + 6 CO → Na (CO)₆+ 3 NaCl The salt can be oxidized to the 17e binary carbonyl V(CO)₆.

Cyclopentadienyl derivatives

130px, (Cycloheptatrienyl)(cyclopentadienyl)vanadium is one of many organovanadium compounds that is paramagnetic.

Vanadocene dichloride Vanadocene dichloride is an organometallic complex with formula ( ''η''5- C5H5)2VCl2 (commonly abbreviated as Cp2VCl2). It is a structural analogue of titanocene dichloride but with vanadium(IV) instead of titanium(IV). This compound has one unpa ...

, the first organovanadium complexes to be reported, is prepared from

sodium cyclopentadienyl Sodium cyclopentadienide is an organosodium compound with the formula C5H5Na. The compound is often abbreviated as NaCp, where Cp− is the cyclopentadienide anion. Sodium cyclopentadienide is a colorless solid, although samples often are p ...

and

vanadium tetrachloride Vanadium tetrachloride is the inorganic compound with the formula V Cl4. This bright red liquid serves as a useful reagent for the preparation of other vanadium compounds. Synthesis, bonding, basic properties With one more valence electron than ...

: :2 NaC₅H₅ + VCl₄ → VCp₂Cl₂ + 2NaCl Reduction of this compound gives the parent

vanadocene Vanadocene, bis(η5-cyclopentadienyl) vanadium, is the organometallic compound with the formula V(C5H5)2, commonly abbreviated Cp2V. It is a violet crystalline, paramagnetic solid. Vanadocene has relatively limited practical use, but it has been ex ...

(Cp₂V): :VCp₂Cl₂ + LiAlH₄ → VCp₂

Vanadocene Vanadocene, bis(η5-cyclopentadienyl) vanadium, is the organometallic compound with the formula V(C5H5)2, commonly abbreviated Cp2V. It is a violet crystalline, paramagnetic solid. Vanadocene has relatively limited practical use, but it has been ex ...

is the lightest

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 can ...

metallocene A metallocene is a compound typically consisting of two cyclopentadienyl anions (, abbreviated Cp) bound to a metallic element, metal center (M) in the oxidation state II, with the resulting general formula Closely related to the metallocenes are ...

that is isolable at room temperature. Vanadocene reacts with high pressures of carbon monoxide to give CpV(CO)₄.

Photolysis Photodissociation, photolysis, photodecomposition, or photofragmentation is a chemical reaction in which molecules of a chemical compound are broken down by photons. It is defined as the interaction of one or more photons with one target molecule. ...

of the tetracarbonyl gives Cp₂V₂(CO)₅. Several analogous

indenyl complex In organometallic chemistry, a transition metal indenyl complex is a coordination compound that contains one or more indenyl ligands. The indenyl ligand is formally the anion derived from deprotonation of indene. The hapticity, η5-indenyl ligand i ...

es are known. Monocyclopentadienyl vanadium chlorides include CpVCl₃ and the diamagnetic CpVOCl₂.

Arene complexes

Vanadium forms a variety of

arene Aromatic compounds, also known as "mono- and polycyclic aromatic hydrocarbons", are organic compounds containing one or more aromatic rings. The parent member of aromatic compounds is benzene. The word "aromatic" originates from the past grouping ...

complexes, e.g. with

benzene Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, ...

: :VCl₄ + Al + 2C₆H₆ → (η⁶-C₆H₆)₂lCl₄ : (η⁶-C₆H₆)₂lCl₄ + H₂O → V(η⁶-C₆H₆)₂ + ...

Alkyl and aryl derivatives

A handful of

alkyl In organic chemistry, an alkyl group is an alkane missing one hydrogen. The term ''alkyl'' is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl is derived from a cycloalk ...

and

aryl In organic chemistry, an aryl is any functional group or substituent derived from an aromatic ring, usually an aromatic hydrocarbon, such as phenyl and naphthyl. "Aryl" is used for the sake of abbreviation or generalization, and "Ar" is used as ...

complexes exist. The reactive species V(

mesityl Mesitylene or 1,3,5-trimethylbenzene is a derivative of benzene with three methyl substituents positioned symmetrically around the ring. The other two isomeric trimethylbenzenes are 1,2,4-trimethylbenzene (pseudocumene) and 1,2,3-trimethylbenzen ...

)₃ forms from VCl₃: :VCl₃(THF)₃ + 3 LiC₆H₂-2,4,6-Me₃ → V(C₆H₂-2,4,6-Me₃)₃(THF) + 3 LiCl This species binds CO and, under appropriate conditions, N₂. V(

)₃ adds a fourth mesityl group and the resulting "ate complex" can be oxidized to the vanadium(IV) derivative: : V(mes)₃(THF) + LiMes → Li (mes)₄: Li (mes)₄ + air → V(mes)₄(THF) The tetrakis(norbornyl) complex is also known.

Vanadium oxytrichloride Vanadium oxytrichloride is the inorganic compound with the formula VOCl3. This yellow distillable liquid hydrolyzes readily in air. It is an oxidizing agent. It is used as a reagent in organic synthesis. Samples often appear red or orange o ...

is a starting material for organovanadium(IV) and organovanadium(V) compounds: : VOCl₃ + Li(mes) → Li O(mes)₃: Li O(mes)₃+

chloranil Chloranil is a quinone with the molecular formula C6Cl4O2. Also known as tetrachloro-1,4-benzoquinone, it is a yellow solid. Like the parent benzoquinone, chloranil is a planar molecule J.-M. Lü, S. V. Rosokha, I. S. Neretin and J. K. Kochi, "Qui ...

→ VO(mes)₃ : VOCl₃ + ZnPh₂ → VOPhCl₂ + "ZnPh(Cl)"

Catalysts and reagents

Well-defined vanadium compounds do not appear as catalysts in any commercial process. However organovanadium species are clearly implicated as catalysts for the production of butadiene-based rubbers. These catalysts are generated in situ by treating soluble coordination complexes such as

vanadium(III) acetylacetonate Vanadium(III) acetylacetonate is the coordination compound with the formula V(C5H7O2)3, sometimes designated as V(acac)3. It is an orange-brown solid that is soluble in organic solvents. Structure and synthesis The complex has idealized D3 sy ...

with

organoaluminium 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 ...

activators.

References

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