All Topics  
Diene

 

 
   Email Print
   Bookmark   Link
 

 

Diene
 
 
  Topics Diene Topic Home

Dienes or diolefins are hydrocarbon
Hydrocarbon

In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. With relation to chemical terminology, aromatic hydrocarbons or arenes, alkanes, alkenes and alkyne-based compounds composed entirely of carbon or hydrogen are referred to as "pure" hydrocarbons, whereas other hydrocarbons with bonded com...
s which contain two double bonds
Covalent bond

A covalent bond is a form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms, or between atoms and other covalent bonds....
. Dienes are intermediate between alkene
Alkene

In organic chemistry, an alkene, olefin, or olefine is an Saturation chemical compound containing at least one carbon-to-carbon double bond....
s and polyene
Polyene

Polyenes are poly-Saturation organic compounds that contain one or more sequences of alternating double and single carbon-carbon bonds. These double carbon-carbon bonds interact in a process known as Conjugated system, which results in an overall lower energy state of the molecule....
s.

es can be divided into three classes:
  1. Unconjugated dienes have the double bonds separated by two or more single bonds.
  2. Conjugated dienes have conjugated
    Conjugated system

    A conjugated system occurs in an organic compound where atoms covalently Chemical bond with alternating single and multiple bonds and influence each other to produce a region called electron delocalization....
     double bonds separated by one single bond. They are also the most stable.
  3. Cumulated dienes have the double bonds sharing a common atom as in a group of compounds called allene
    Allene

    An allene is a hydrocarbon in which one atom of carbon is connected by covalent bond with two other atoms of carbon. Allene also is the common name for the parent compound of this series, propadiene....
    s.
  4. Heterodienes have one or more of the unsaturated carbon atoms replaced with a heteroatom
    Heteroatom

    In the organic nomenclature of organic chemistry, a heteroatom is any atom that is not carbon or hydrogen. It is typically, but not exclusively, nitrogen, oxygen, sulfur, phosphorus, boron, chlorine, bromine, or iodine....
    .



In organic chemistry
Organic chemistry

Organic chemistry is a discipline within chemistry which involves the science study of the structure, properties, composition, chemical reaction, and preparation of chemical compounds that contain carbon....
 a conjugated diene is also a functional group
Functional group

In organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules....
, with a general formula of CnH2n-2.






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



Encyclopedia


Dienes or diolefins are hydrocarbon
Hydrocarbon

In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. With relation to chemical terminology, aromatic hydrocarbons or arenes, alkanes, alkenes and alkyne-based compounds composed entirely of carbon or hydrogen are referred to as "pure" hydrocarbons, whereas other hydrocarbons with bonded com...
s which contain two double bonds
Covalent bond

A covalent bond is a form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms, or between atoms and other covalent bonds....
. Dienes are intermediate between alkene
Alkene

In organic chemistry, an alkene, olefin, or olefine is an Saturation chemical compound containing at least one carbon-to-carbon double bond....
s and polyene
Polyene

Polyenes are poly-Saturation organic compounds that contain one or more sequences of alternating double and single carbon-carbon bonds. These double carbon-carbon bonds interact in a process known as Conjugated system, which results in an overall lower energy state of the molecule....
s.

Classes

Dienes can be divided into three classes:
  1. Unconjugated dienes have the double bonds separated by two or more single bonds.
  2. Conjugated dienes have conjugated
    Conjugated system

    A conjugated system occurs in an organic compound where atoms covalently Chemical bond with alternating single and multiple bonds and influence each other to produce a region called electron delocalization....
     double bonds separated by one single bond. They are also the most stable.
  3. Cumulated dienes have the double bonds sharing a common atom as in a group of compounds called allene
    Allene

    An allene is a hydrocarbon in which one atom of carbon is connected by covalent bond with two other atoms of carbon. Allene also is the common name for the parent compound of this series, propadiene....
    s.
  4. Heterodienes have one or more of the unsaturated carbon atoms replaced with a heteroatom
    Heteroatom

    In the organic nomenclature of organic chemistry, a heteroatom is any atom that is not carbon or hydrogen. It is typically, but not exclusively, nitrogen, oxygen, sulfur, phosphorus, boron, chlorine, bromine, or iodine....
    .

Classes of Dienes
Isoprene Structure


In organic chemistry
Organic chemistry

Organic chemistry is a discipline within chemistry which involves the science study of the structure, properties, composition, chemical reaction, and preparation of chemical compounds that contain carbon....
 a conjugated diene is also a functional group
Functional group

In organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules....
, with a general formula of CnH2n-2. A classic organic reaction
Organic reaction

Organic reactions are chemical reactions involving organic compounds. The basic organic chemistry reaction types are addition reactions, elimination reactions, substitution reactions, pericyclic reactions, rearrangement reactions and organic redox reaction....
 for the synthesis of dienes is the Whiting reaction
Whiting reaction

The Whiting reaction is an organic reaction converting a propargyl diol into a diene using lithium aluminium hydride.This organic reduction has been applied in the synthesis of facapentadiene....
.

1,3-butadiene undergoes 1,2-addition and 1,4-addition.

Reactions with dienes

The 1,3 configuration of double bonds found in 1,3-butadiene (conjugated double bonds) make these types of dienes capable of participating in more reaction types than is the case for molecule
Molecule

In chemistry, a molecule is defined as a sufficiently stable, electric charge neutral group of at least two atoms in a definite arrangement held together by very strong chemical bonds....
s with either just a single alkene
Alkene

In organic chemistry, an alkene, olefin, or olefine is an Saturation chemical compound containing at least one carbon-to-carbon double bond....
 functional group
Functional group

In organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules....
 or with multiple, but non-alternating, alkene groups. One possible reaction for such dienes is the 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....
 for example Danishefsky’s diene
Danishefsky’s diene

Danishefsky?s diene is an organic compound and a diene with the formal name trans-1-methoxy-3-trimethylsilyloxy-1,3-butadiene named after Samuel J....
.

External links

  • IUPACs Gold Book
    Gold Book

    Compendium of Chemical Terminology is a book published by IUPAC containing internationally accepted definitions for terms in chemistry. Work on the first edition was initiated by Victor Gold, hence its informal name, the Gold Book....
     definition of dienes