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  2. Michael addition reaction - Wikipedia

    en.wikipedia.org/wiki/Michael_Addition_Reaction

    For example, the image below shows the addition of ethylmagnesium bromide to ethyl sorbate 1 using a copper catalyst with a reversed josiphos (R,S)-(–)-3 ligand. [35] This reaction produced the 1,6-addition product 2 in 0% yield, the 1,6-addition product 3 in approximately 99% yield, and the 1,4-addition product 4 in less than 2% yield.

  3. Addition reaction - Wikipedia

    en.wikipedia.org/wiki/Addition_reaction

    Depending on the product structure, it could promptly react further to eject a leaving group to give the addition–elimination reaction sequence. Addition reactions are useful in analytic chemistry, as they can identify the existence and number of double bonds in a molecule. For example, bromine addition will consume a bromine solution ...

  4. Reductive elimination - Wikipedia

    en.wikipedia.org/wiki/Reductive_elimination

    Reductive elimination is an elementary step in organometallic chemistry in which the oxidation state of the metal center decreases while forming a new covalent bond between two ligands. It is the microscopic reverse of oxidative addition, and is often the product-forming step in many catalytic processes. Since oxidative addition and reductive ...

  5. Markovnikov's rule - Wikipedia

    en.wikipedia.org/wiki/Markovnikov's_rule

    Also called Kharasch effect (named after Morris S. Kharasch), these reactions that do not involve a carbocation intermediate may react through other mechanisms that have regioselectivities not dictated by Markovnikov's rule, such as free radical addition. Such reactions are said to be anti-Markovnikov, since the halogen adds to the less ...

  6. Stephen aldehyde synthesis - Wikipedia

    en.wikipedia.org/wiki/Stephen_aldehyde_synthesis

    This reaction involves the preparation of aldehydes (R-CHO) from nitriles (R-CN) using tin(II) chloride (SnCl 2), hydrochloric acid (HCl) and quenching the resulting iminium salt ([R-CH=NH 2] + Cl −) with water (H 2 O). [1] [2] During the synthesis, ammonium chloride is also produced. It is a type of nucleophilic addition reaction. Stephen ...

  7. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    For example, the overall rate constant k for a two-step reaction A ⇌ B, B → C is given by k = k 2 K 1, where k 2 is the rate constant of the rate-limiting slow second step and K 1 is the equilibrium constant of the rapid first step. In some reactions, K 1 decreases with temperature more rapidly than k 2 increases, so that k actually ...

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  9. Rate-determining step - Wikipedia

    en.wikipedia.org/wiki/Rate-determining_step

    As an example, consider the gas-phase reaction NO 2 + CO → NO + CO 2.If this reaction occurred in a single step, its reaction rate (r) would be proportional to the rate of collisions between NO 2 and CO molecules: r = k[NO 2][CO], where k is the reaction rate constant, and square brackets indicate a molar concentration.