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  2. Chemical clock - Wikipedia

    en.wikipedia.org/wiki/Chemical_clock

    In an iodine clock reaction, colour changes after a time delay.. A chemical clock (or clock reaction) is a complex mixture of reacting chemical compounds in which the onset of an observable property (discoloration or coloration) occurs after a predictable induction time due to the presence of clock species at a detectable amount. [1]

  3. Concerted metalation deprotonation - Wikipedia

    en.wikipedia.org/wiki/Concerted_metalation_de...

    Concerted metalation-deprotonation (CMD) is a mechanistic pathway through which transition-metal catalyzed C–H activation reactions can take place. In a CMD pathway, the C–H bond of the substrate is cleaved and the new C–Metal bond forms through a single transition state. [1]

  4. Reaction mechanism - Wikipedia

    en.wikipedia.org/wiki/Reaction_mechanism

    In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical reaction occurs. [1] A chemical mechanism is a theoretical conjecture that tries to describe in detail what takes place at each stage of an overall chemical reaction. The detailed steps of a reaction are not observable in most cases.

  5. Hammett equation - Wikipedia

    en.wikipedia.org/wiki/Hammett_equation

    In organic chemistry, the Hammett equation describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para-substituents to each other with just two parameters: a substituent constant and a reaction constant.

  6. Dynamic kinetic resolution in asymmetric synthesis - Wikipedia

    en.wikipedia.org/wiki/Dynamic_Kinetic_Resolution...

    Dynamic kinetic resolution of 1,4 conjugate reduction. The rate-limiting step is the copper complex interaction with the double bond and the transfer of hydrogen. 1,4 conjugate reduction to cyclic enones. Copper proved to be an excellent metal in this reaction due to its ability to complex with the oxygen when the hydrogen was added.

  7. Iodine clock reaction - Wikipedia

    en.wikipedia.org/wiki/Iodine_clock_reaction

    The iodine clock reaction is a classical chemical clock demonstration experiment to display chemical kinetics in action; it was discovered by Hans Heinrich Landolt in 1886. [1] The iodine clock reaction exists in several variations, which each involve iodine species ( iodide ion, free iodine, or iodate ion) and redox reagents in the presence of ...

  8. Chain termination - Wikipedia

    en.wikipedia.org/wiki/Chain_termination

    The termination steps of free radical polymerization steps are of two types: recombination and disproportionation. [2] In a recombination step, two growing chain radicals (denoted by •) form a covalent bond in a single stable molecule. For the example of a vinyl polymer,

  9. Grunwald–Winstein equation - Wikipedia

    en.wikipedia.org/wiki/Grunwald–Winstein_equation

    In physical organic chemistry, the Grunwald–Winstein equation is a linear free energy relationship between relative rate constants and the ionizing power of various solvent systems, describing the effect of solvent as nucleophile on different substrates.