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  2. Diels–Alder reaction - Wikipedia

    en.wikipedia.org/wiki/Diels–Alder_reaction

    Diels–Alder reaction, simplest example. In organic chemistry, the Diels–Alder reaction is a chemical reaction between a conjugated diene and a substituted alkene, commonly termed the dienophile, to form a substituted cyclohexene derivative. It is the prototypical example of a pericyclic reaction with a concerted mechanism.

  3. Aza-Diels–Alder reaction - Wikipedia

    en.wikipedia.org/wiki/Aza-Diels–Alder_reaction

    The imine is often generated in situ from an amine and formaldehyde.An example is the reaction of cyclopentadiene with benzylamine to an aza norbornene. [9]The catalytic cycle starts with the reactions of the aromatic amine with formaldehyde to the imine and the reaction of the ketone with proline to the diene.

  4. Retro-Diels–Alder reaction - Wikipedia

    en.wikipedia.org/wiki/Retro-Diels–Alder_reaction

    Release of nitrogen from six-membered, cyclic diazenes is common and often spontaneous at room temperature. Such a reaction can be utilized in click reactions where alkanes react with a 1,2,4,5-tetrazine in a diels alder then retro diels alder reaction with the loss of nitrogen. In this another example, the epoxide shown undergoes rDA at 0 °C.

  5. Inverse electron-demand Diels–Alder reaction - Wikipedia

    en.wikipedia.org/wiki/Inverse_electron-demand...

    The inverse electron demand Diels–Alder reaction, or DA INV or IEDDA [1] is an organic chemical reaction, in which two new chemical bonds and a six-membered ring are formed. It is related to the Diels–Alder reaction , but unlike the Diels–Alder (or DA) reaction, the DA INV is a cycloaddition between an electron-rich dienophile and an ...

  6. Dienone - Wikipedia

    en.wikipedia.org/wiki/Dienone

    Dibenzylideneacetone is a well known dienone. A dienone is a class of organic compounds with the general formula (R 2 C=CR) 2 C=O, where R is any substituent, but often H.They are formally "derived from 1,4-diene compounds by conversion of a –CH2– group into –C(=O)– group", resulting in "a conjugated structure".

  7. Tetraphenylcyclopentadienone - Wikipedia

    en.wikipedia.org/wiki/Tetraphenylcyclopentadienone

    The central ring can serve as a diene in Diels–Alder reactions with various dienophiles. For example, reaction with benzyne leads to 1,2,3,4-tetraphenylnaphthalene and reaction with diphenylacetylene leads to hexaphenylbenzene. [5] In this way, it is a precursor to graphene-like molecules, [6] such as coronene.

  8. Diene - Wikipedia

    en.wikipedia.org/wiki/Diene

    Conjugated dienes are more stable than other dienes because of resonance. Unconjugated dienes have the double bonds separated by two or more single bonds. They are usually less stable than isomeric conjugated dienes. This can also be known as an isolated diene. Some dienes: A: 1,2-Propadiene, also known as allene, is the simplest cumulated diene.

  9. Ketene cycloaddition - Wikipedia

    en.wikipedia.org/wiki/Ketene_cycloaddition

    Cyclic and acyclic dienes generally give cyclobutanones, rather than Diels-Alder adducts. In reactions of cyclic dienes, the larger ketene substituent is placed in the endo position. [11] Fulvenes typically react in the ring, leaving the double bond intact. [12] (6) Ketenes undergo [2+2] cycloaddition with ketones and aldehydes to give β-lactones.