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  2. Buchner ring expansion - Wikipedia

    en.wikipedia.org/wiki/Buchner_ring_expansion

    The Buchner ring expansion is a two-step organic C-C bond forming reaction used to access 7-membered rings. The first step involves formation of a carbene from ethyl diazoacetate, which cyclopropanates an aromatic ring. The ring expansion occurs in the second step, with an electrocyclic reaction opening the cyclopropane ring to form the 7 ...

  3. 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.

  4. Steam cracking - Wikipedia

    en.wikipedia.org/wiki/Steam_cracking

    Steam cracker process diagram Gibbs free energy per carbon atom. This shows that at high temperature, hexane can split into ethane and ethylene ("Ethen"), and ethane can split into ethylene and hydrogen. But ethylene can decompose into methane and carbon if given too much time, and all the hydrocarbons can decompose into carbon and hydrogen.

  5. Reaction step - Wikipedia

    en.wikipedia.org/wiki/Reaction_step

    In chemistry, a reaction step of a chemical reaction is defined as: "An elementary reaction, constituting one of the stages of a stepwise reaction in which a reaction intermediate (or, for the first step, the reactants) is converted into the next reaction intermediate (or, for the last step, the products) in the sequence of intermediates between reactants and products". [1]

  6. Van der Waals constants (data page) - Wikipedia

    en.wikipedia.org/wiki/Van_der_Waals_constants...

    Printable version; In other projects ... To convert from / ... Benzene: 18.24 0.1193 Bromobenzene: 28.94 0.1539 Butane: 14.66

  7. Oxidative coupling of methane - Wikipedia

    en.wikipedia.org/wiki/Oxidative_coupling_of_methane

    The reaction is exothermic (∆H = -280 kJ/mol) and occurs at high temperatures (750–950 ˚C). [3] In the reaction, methane (CH 4) is activated heterogeneously on the catalyst surface, forming methyl free radicals, which then couple in the gas phase to form ethane (C 2 H 6). The ethane subsequently undergoes dehydrogenation to form ethylene ...

  8. Catalytic reforming - Wikipedia

    en.wikipedia.org/wiki/Catalytic_reforming

    A side reaction is hydrogenolysis, which produces light hydrocarbons of lower value, such as methane, ethane, propane and butanes. Continuous Catalytic reforming (CCR) unit In addition to a gasoline blending stock, reformate is the main source of aromatic bulk chemicals such as benzene , toluene , xylene and ethylbenzene , which have diverse ...

  9. Transfer hydrogenation - Wikipedia

    en.wikipedia.org/wiki/Transfer_hydrogenation

    In this case, an alkane is formed, along with a benzene. The gain of aromatic stabilization energy when the benzene is formed is the driving force of the reaction. Pd can be used as a catalyst and a temperature of 100 °C is employed. More exotic transfer hydrogenations have been reported, including this intramolecular one: Transfer hydrogenation