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  2. Electrophile - Wikipedia

    en.wikipedia.org/wiki/Electrophile

    For example, the reaction of HCl with ethylene furnishes chloroethane. The reaction proceeds with a cation intermediate, being different from the above halogen addition. An example is shown below: Proton (H +) adds (by working as an electrophile) to one of the carbon atoms on the alkene to form cation 1.

  3. Directed ortho metalation - Wikipedia

    en.wikipedia.org/wiki/Directed_ortho_metalation

    An electrophile reacts in the next phase in an electrophilic aromatic substitution with a strong preference for the lithium ipso position replacing the lithium atom. Ordinary electrophilic substitutions with an activating group show preference for both the ortho and para position, this reaction demonstrates increased regioselectivity because ...

  4. Electrophilic substitution - Wikipedia

    en.wikipedia.org/wiki/Electrophilic_substitution

    This reaction is similar to nucleophilic aliphatic substitution where the reactant is a nucleophile rather than an electrophile. The four possible electrophilic aliphatic substitution reaction mechanisms are S E 1, S E 2(front), S E 2(back) and S E i (Substitution Electrophilic), which are also similar to the nucleophile counterparts S N 1 and ...

  5. Carbonyl α-substitution reaction - Wikipedia

    en.wikipedia.org/wiki/Carbonyl_α-substitution...

    A hydrogen on the α position of a carbonyl compound is weakly acidic and can be removed by a strong base to yield an enolate ion. In comparing acetone (pK a = 19.3) with ethane (pK a = 60), for instance, the presence of a neighboring carbonyl group increases the acidity of the ketone over the alkane by a factor of 10 40.

  6. Electrophilic addition - Wikipedia

    en.wikipedia.org/wiki/Electrophilic_addition

    In organic chemistry, an electrophilic addition (A E) reaction is an addition reaction where a chemical compound containing a double or triple bond has a π bond broken, with the formation of two new σ bonds. [1] The driving force for this reaction is the formation of an electrophile X + that forms a covalent bond with an electron-rich ...

  7. Substitution reaction - Wikipedia

    en.wikipedia.org/wiki/Substitution_reaction

    Coupling reactions are a class of metal-catalyzed reactions involving an organometallic compound RM and an organic halide R′X that together react to form a compound of the type R-R′ with formation of a new carbon–carbon bond. Examples include the Heck reaction, Ullmann reaction, and Wurtz–Fittig reaction. Many variations exist. [3]

  8. Electrophilic aromatic directing groups - Wikipedia

    en.wikipedia.org/wiki/Electrophilic_aromatic...

    A carbon atom with a larger coefficient will be preferentially attacked, due to more favorable orbital overlap with the electrophile. [ 16 ] The perturbation of a conjugating electron-withdrawing or electron-donating group causes the π electron distribution on a benzene ring to resemble ( very slightly !) an electron-deficient benzyl cation or ...

  9. Mannich reaction - Wikipedia

    en.wikipedia.org/wiki/Mannich_reaction

    The Schiff base is an electrophile which reacts in a second step in an electrophilic addition with an enol formed from a carbonyl compound containing an acidic alpha-proton. The Mannich reaction is a condensation reaction. [4]: 140 In the Mannich reaction, primary or secondary amines or ammonia react with formaldehyde to form a Schiff base ...