All Topics  
Furan

 

 
   Email Print
   Bookmark   Link
 

 

Furan
 
 
  Topics Furan Topic Home

Furan, also known as furane and furfuran, is a heterocyclic
Heterocyclic compound

Heterocyclic compounds are organic compounds containing at least one atom of carbon, and at least one element other than carbon, such as sulfur, oxygen or nitrogen within a ring structure....
 organic compound
Organic compound

An organic compound is any member of a large class of chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of compounds such as carbonates, simple oxides of carbon and cyanides, as well as the allotropes of carbon, are considered Inorganic compound....
. It is typically derived by the thermal decomposition
Thermal decomposition

Thermal decomposition, also called thermolysis, is defined as a chemical reaction when a chemical substance breaks up into at least two chemical substances when heated....
 of pentose
Pentose

A pentose is a monosaccharide with five carbon atoms.They either have an aldehyde functional group in position 1 , or a ketone functional group in position 2 ....
-containing materials, cellulosic solids especially pine-wood. Furan is a colorless, flammable, highly volatile
Volatility (chemistry)

Volatility in the context of chemistry, physics and thermodynamics is a measure of the tendency of a substance to vaporize. It has also been defined as a measure of how readily a substance vaporizes....
 liquid with a boiling point
Boiling point

The boiling point of a liquid is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid....
 close to room temperature. It is toxic and may be carcinogenic. Catalytic hydrogenation (see redox
Redox

Redox describes all chemical reactions in which atoms have their oxidation number changed.This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide or the reduction of carbon by hydrogen to yield methane , or it can be a complex process such as the oxidation of sugar in the human body through a ser...
) of furan with a palladium
Palladium

Palladium is a rare and lustrous silvery-white metal that was discovered in 1803 by William Hyde Wollaston, who named it palladium after the 2 Pallas, which in turn, was named after the epithet of the Greek mythology goddess Athena, acquired by her when she slew Athena#Pallas_Athena....
 catalyst gives tetrahydrofuran
Tetrahydrofuran

Tetrahydrofuran is a colorless, water-miscible organic liquid with low-viscosity at "room" temperature and pressure . It is a Heterocyclic compound compound with a chemical formula C4H8O, and is the fully Hydrogenation analog of the aromatic organic compound furan....
.

name furan comes from the Latin furfur, which means bran
Bran

Bran is the hard outer layer of grain and consists of combined aleurone and pericarp. Along with cereal germ, it is an integral part of whole grains, and is often produced as a by-product of milling in the production of refined grains....
.






Discussion
Ask a question about 'Furan'
Start a new discussion about 'Furan'
Answer questions from other users
Full Discussion Forum



Recent Posts

Its Resonance structur
What is resonsnce structur of furane?








Encyclopedia


Furan, also known as furane and furfuran, is a heterocyclic
Heterocyclic compound

Heterocyclic compounds are organic compounds containing at least one atom of carbon, and at least one element other than carbon, such as sulfur, oxygen or nitrogen within a ring structure....
 organic compound
Organic compound

An organic compound is any member of a large class of chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of compounds such as carbonates, simple oxides of carbon and cyanides, as well as the allotropes of carbon, are considered Inorganic compound....
. It is typically derived by the thermal decomposition
Thermal decomposition

Thermal decomposition, also called thermolysis, is defined as a chemical reaction when a chemical substance breaks up into at least two chemical substances when heated....
 of pentose
Pentose

A pentose is a monosaccharide with five carbon atoms.They either have an aldehyde functional group in position 1 , or a ketone functional group in position 2 ....
-containing materials, cellulosic solids especially pine-wood. Furan is a colorless, flammable, highly volatile
Volatility (chemistry)

Volatility in the context of chemistry, physics and thermodynamics is a measure of the tendency of a substance to vaporize. It has also been defined as a measure of how readily a substance vaporizes....
 liquid with a boiling point
Boiling point

The boiling point of a liquid is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid....
 close to room temperature. It is toxic and may be carcinogenic. Catalytic hydrogenation (see redox
Redox

Redox describes all chemical reactions in which atoms have their oxidation number changed.This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide or the reduction of carbon by hydrogen to yield methane , or it can be a complex process such as the oxidation of sugar in the human body through a ser...
) of furan with a palladium
Palladium

Palladium is a rare and lustrous silvery-white metal that was discovered in 1803 by William Hyde Wollaston, who named it palladium after the 2 Pallas, which in turn, was named after the epithet of the Greek mythology goddess Athena, acquired by her when she slew Athena#Pallas_Athena....
 catalyst gives tetrahydrofuran
Tetrahydrofuran

Tetrahydrofuran is a colorless, water-miscible organic liquid with low-viscosity at "room" temperature and pressure . It is a Heterocyclic compound compound with a chemical formula C4H8O, and is the fully Hydrogenation analog of the aromatic organic compound furan....
.

History

The name furan comes from the Latin furfur, which means bran
Bran

Bran is the hard outer layer of grain and consists of combined aleurone and pericarp. Along with cereal germ, it is an integral part of whole grains, and is often produced as a by-product of milling in the production of refined grains....
. The first furan derivative to be described was 2-furoic acid, by Carl Wilhelm Scheele
Carl Wilhelm Scheele

Carl Wilhelm Scheele was a Germany-Sweden pharmaceutical chemist, born in Stralsund, Western Pomerania, Germany . He was the discoverer of many chemical substances, most notably discovering oxygen , molybdenum and chlorine before Humphry Davy....
 in 1780. Another important derivative, furfural
Furfural

The chemical compound furfural is an industrial chemical derived from a variety of agriculture byproducts, including maize, oat and wheat bran, and sawdust....
, was reported by Johann Wolfgang Döbereiner
Johann Wolfgang Döbereiner

Johann Wolfgang D?bereiner was a Germany Chemistry who is best known for work that foreshadowed the periodic law for the chemical elements....
 in 1831 and characterised nine years later by John Stenhouse
John Stenhouse

John Stenhouse was a Scottish chemist. In 1854, he invented one of the first practical respirators....
. Furan itself was first prepared by Heinrich Limpricht
Heinrich Limpricht

Heinrich Limpricht was a German chemist. Limpricht was a pupil of Friedrich W?hler; he worked on the chemistry of furans and pyrroles, discovering furan in 1870....
 in 1870, although he called it tetraphenol. .

Synthesis and isolation

  • Furan can be obtained from furfural
    Furfural

    The chemical compound furfural is an industrial chemical derived from a variety of agriculture byproducts, including maize, oat and wheat bran, and sawdust....
     by oxidation and decarboxylation
    Decarboxylation

    Decarboxylation is any chemical reaction in which a carboxyl group is split off from a compound as carbon dioxide ....
     of the resulting furan-2-carboxylic acid, the furfural being derived by destructive distillation of corn cobs in the presence of sulfuric acid
    Sulfuric acid

    Sulfuric acid, hydrogen2sulfuroxygen4, is a strong mineral acid. It is soluble in water at all concentrations. Sulfuric acid has many applications, and is one of the top products of the chemical industry....
    .
  • A classic furan organic synthesis
    Organic synthesis

    Organic synthesis is a special branch of chemical synthesis and is concerned with the construction of organic compounds via organic reactions. Organic_chemistry molecules can often contain a higher level of complexity compared to purely Inorganic_chemistry compounds, so the synthesis of organic compounds has developed into one of the most im...
     is the Feist-Benary synthesis
    Feist-Benary synthesis

    The Feist-Benary synthesis is an organic reaction between a-halogen ketones and ?-carbonyl compounds to substituted furan compounds. This condensation reaction is catalysis by amines such as ammonia and pyridine....
    .
  • One of the most simple synthesis methods for furans is the reaction of 1,4-diketone
    Ketone

    In organic chemistry, a ketone is a type of organic compound which contains a carbonyl group bonded to two other carbon atoms in the form:Neither of the substituents R1 and R2 may be equal to hydrogen ....
    s with phosphorus pentoxide
    Phosphorus pentoxide

    Phosphorus pentoxide is a chemical compound with formula Phosphorus2Oxygen5. This white crystalline solid is the anhydride of phosphoric acid....
      (P2O5) in the Paal-Knorr Synthesis
    Paal-Knorr synthesis

    The Paal-Knorr synthesis is a chemical reaction where Diketone are converted to either furans, thiophenes or pyrroles. The reaction is named after Carl Paal and Ludwig Knorr...
    . It is interesting that the thiophene
    Thiophene

    Thiophene is the heterocyclic compound with the formula C4H4S. Consisting of a flat five-membered ring, it is aromaticity as indicated by its extensive substitution reactions....
     formation reaction of 1,4-diketones with Lawesson's reagent
    Lawesson's reagent

    Lawesson's reagent, or LR, is a chemical compound used in organic synthesis as a thiation agent. Lawesson's reagent was first made popular by Sven-Olov Lawesson, who did not, however, invent it....
     also forms furans as side products.


Chemistry

Furan is aromatic because one of the lone pair
Lone pair

A lone pair is a valence electron pair without bonding or sharing with other atoms. They are found in the outermost electron shell of an atom, so lone pairs are a subset of a molecule's valence electrons....
s of electron
Electron

The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle....
s on the oxygen atom is delocalized
Delocalized electron

In chemistry delocalized electrons are electrons in a molecule that are not associated with a single atom or to a covalent bond. Delocalized electrons are contained within an Molecular_orbital that extends over several adjacent atoms....
 into the ring, creating a 4n+2 aromatic system (see Hückel's rule
Hückel's rule

In organic chemistry, H?ckel's rule estimates whether a planar ring molecule will have aromatic properties. The quantum mechanical basis for its formulation was first worked out by physical chemistry Erich H?ckel in 1931....
) similar to benzene
Benzene

Benzene, or benzol, is an organic compound chemical compound and a known carcinogen with the molecular formula Carbon6Hydrogen6....
. Because of the aromaticity, the molecule is flat and lacks discrete double bonds. The other lone pair of electrons of the oxygen atom extends in the plane of the flat ring system. The sp2 hybridization
Orbital hybridisation

In chemistry, hybridisation or hybridization is the concept of mixing atomic orbitals to form new hybrid orbitals suitable for the qualitative description of atomic bonding properties....
 is to allow one of the lone pairs of oxygen to reside in a p orbital and thus allow it to interact within the pi-system.

Due to its aromaticity, furan's behavior is quite dissimilar to that of the more typical heterocyclic ether
Ether

Ether is a class of organic compounds which contain an ether functional group ? an oxygen atom connected to two alkyl or aryl groups ? of general formula R?O?R....
s such as tetrahydrofuran
ThF

Follicular helper T cells, or ThF cells, are antigen-experienced CD4+ T cells found in the lymph node and are identified as being PSGL-1- and CXCR5+....
.
  • It is considerably more reactive than benzene
    Benzene

    Benzene, or benzol, is an organic compound chemical compound and a known carcinogen with the molecular formula Carbon6Hydrogen6....
     in electrophilic substitution
    Electrophilic substitution

    Electrophilic substitution reactions are chemical reactions in which an electrophile displaces another group, typically but not always hydrogen....
     reactions, due to the electron-donating effects of the oxygen heteroatom. Examination of the resonance contributors shows the increased electron density of the ring, leading to increased rates of electrophilic substitution.
  • Furan serves as a diene
    Diene

    Dienes or diolefins are hydrocarbons which contain two covalent bond. Dienes are intermediate between alkenes and polyenes....
     in Diels-Alder reaction
    Diels-Alder reaction

    The Diels-Alder reaction is an organic chemical reaction between a conjugated diene and a substituted alkene, commonly termed the dienophile, to form a substituted cyclohexene system....
    s with electron-deficient dienophiles such as ethyl (E)-3-nitroacrylate. The reaction product is a mixture of isomers with preference for the endo isomer:
Furan Cycloaddition
* Hydrogenation
Hydrogenation

Hydrogenation is the chemical reaction that results from the addition of hydrogen . The process is usually employed to a redox or Saturation organic compounds....
 of furans affords sequentially dihydrofurans and tetrahydrofuran
Tetrahydrofuran

Tetrahydrofuran is a colorless, water-miscible organic liquid with low-viscosity at "room" temperature and pressure . It is a Heterocyclic compound compound with a chemical formula C4H8O, and is the fully Hydrogenation analog of the aromatic organic compound furan....
s.
  • In the Achmatowicz reaction
    Achmatowicz reaction

    The Achmatowicz Reaction is an organic synthesis in which a furan is converted to a dihydropyran. In the original publication by Osman Achmatowicz Jr....
    , furans converted to dihydropyran compounds.


See also

  • 2,5-Dimethylfuran
    2,5-Dimethylfuran

    A derivative of furan, 2,5-Dimethylfuran is a heterocyclic compound of the formula C6H8O. While it may be abbreviated DMF it should not be confused with dimethylformamide....
    , a furan derivative that may be a possible biofuel
    Biofuel

    Biofuel is defined as solid, liquid or gaseous fuel derived from relatively recently dead biological material and is distinguished from fossil fuels, which are petroleum#formation....
  • Tetrahydrofuran
    Tetrahydrofuran

    Tetrahydrofuran is a colorless, water-miscible organic liquid with low-viscosity at "room" temperature and pressure . It is a Heterocyclic compound compound with a chemical formula C4H8O, and is the fully Hydrogenation analog of the aromatic organic compound furan....
     (THF), the fully hydrogenated
    Hydrogenation

    Hydrogenation is the chemical reaction that results from the addition of hydrogen . The process is usually employed to a redox or Saturation organic compounds....
     analog of furan and a common solvent
    Solvent

    A solvent is a liquid or gas that dissolves a solid, liquid, or gaseous solute, resulting in a solution.The most common solvent in everyday life is water....
    .
  • Pyrrole
    Pyrrole

    Pyrrole, or pyrrol, is a heterocyclic aromatic organic compound, a five-membered ring with the chemical formula carbon4hydrogen4nitrogenH....
    , the nitrogen
    Nitrogen

    Nitrogen is a chemical element that has the symbol N and atomic number 7 and atomic mass 14.00674?. Elemental nitrogen is a colorless, odorless, tasteless and mostly inert diatomic gas at standard conditions, constituting 78% by volume of Earth's atmosphere....
     analog of furan.
  • Thiophene
    Thiophene

    Thiophene is the heterocyclic compound with the formula C4H4S. Consisting of a flat five-membered ring, it is aromaticity as indicated by its extensive substitution reactions....
    , the sulfur
    Sulfur

    Sulfur or sulphur is the chemical element that has the atomic number 16. It is denoted with the symbol S. It is an abundant Valence non-metal....
     analog of furan.
  • Selenophene, the selenium
    Selenium

    Selenium is a chemical element with the atomic number 34, represented by the chemical symbol Se, an atomic mass of 78.96. It is a nonmetal, chemically related to sulfur and tellurium, and rarely occurs in its elemental state in nature....
     analog of furan.
  • Tellurophene, the tellurium
    Tellurium

    Tellurium is a chemical element that has the symbol Te and atomic number 52. A brittle silver-white metalloid which looks like tin, tellurium is chemically related to selenium and sulfur....
     analog of furan.
  • Benzofuran
    Benzofuran

    Benzofuran is the heterocyclic compound consisting of fused benzene and furan rings. It is the parent of many related compounds with more complex structures....
    , furan with a fused benzene ring.
  • Dibenzofuran
    Dibenzofuran

    Dibenzofuran, is a heterocyclic organic compound with the chemical structure shown at right. It is an aromatic compound that has two benzene rings fused to one furan ring in the middle....
    , a compound class similar to dibenzodioxin
    Dioxin

    Polychlorinated dibenzodioxins , or simply dioxins, are a group of polyhalogenated compounds which are significant because they act as environmental pollutants....
    s.
  • Simple aromatic ring
    Simple aromatic ring

    Simple aromatic rings, also known as simple arenes or simple aromatics, are aromatic organic compounds that consist only of a conjugated system planar ring system with delocalized_electron pi electron clouds....
    s
  • Furanose
    Furanose

    A furanose is a simple sugar that contains a five-membered furan-based ring structure and is a sub-terminal ketone which gives it reducing power....


External links