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  2. Alkane metathesis - Wikipedia

    en.wikipedia.org/wiki/Alkane_metathesis

    These systems catalyze the conversion of ethane to give methane, propane and traces of butane. [1] Cross metathesis can also take place, for example methane and propane can react to give two molecules of ethane. Ethane reacts with toluene to give ethylbenzene and xylene. The reaction involves metallocyclobutane intermediates just as in olefin ...

  3. Transalkylation - Wikipedia

    en.wikipedia.org/wiki/Transalkylation

    Reaction of toluene to produce benzene and xylene. Transalkylation, as used by the petrochemical industry, is often used to convert toluene into benzene and xylenes. This is achieved through a disproportionation reaction of toluene in which one toluene molecule transfers its methyl group to another one. The reaction is not selective, and the ...

  4. Conversion (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Conversion_(chemistry)

    Conversion and its related terms yield and selectivity are important terms in chemical reaction engineering.They are described as ratios of how much of a reactant has reacted (X — conversion, normally between zero and one), how much of a desired product was formed (Y — yield, normally also between zero and one) and how much desired product was formed in ratio to the undesired product(s) (S ...

  5. Buchner ring expansion - Wikipedia

    en.wikipedia.org/wiki/Buchner_ring_expansion

    The reaction mechanism of a Buchner ring expansion begins with carbene formation from ethyl-diazoacetate generated initially through photochemical or thermal reactions with extrusion of nitrogen. carbene mechanism. The generated carbene adds to one of the double bonds of benzene to form the cyclopropane ring. carbene insertion

  6. Benzene - Wikipedia

    en.wikipedia.org/wiki/Benzene

    Benzene is sufficiently nucleophilic that it undergoes substitution by acylium ions and alkyl carbocations to give substituted derivatives. Electrophilic aromatic substitution of benzene. The most widely practiced example of this reaction is the ethylation of benzene. Approximately 24,700,000 tons were produced in 1999. [73]

  7. Aromatization - Wikipedia

    en.wikipedia.org/wiki/Aromatization

    Aromatization is a chemical reaction in which an aromatic system is formed from a single nonaromatic precursor. Typically aromatization is achieved by dehydrogenation of existing cyclic compounds, illustrated by the conversion of cyclohexane into benzene. Aromatization includes the formation of heterocyclic systems. [1]

  8. Isomerization - Wikipedia

    en.wikipedia.org/wiki/Isomerization

    In certain kinds of alkene polymerization reactions, chain walking is an isomerization process that introduces branches into growing polymers. [citation needed] The trans isomer of resveratrol can be converted to the cis isomer in a photochemical reaction. [6] Thermal rearrangement of azulene to naphthalene has been observed. [7]

  9. Energy profile (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Energy_profile_(chemistry)

    Figure 6:Reaction Coordinate Diagrams showing reactions with 0, 1 and 2 intermediates: The double-headed arrow shows the first, second and third step in each reaction coordinate diagram. In all three of these reactions the first step is the slow step because the activation energy from the reactants to the transition state is the highest.