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  2. Electrophilic aromatic directing groups - Wikipedia

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

    An electron donating group (EDG) or electron releasing group (ERG, Z in structural formulas) is an atom or functional group that donates some of its electron density into a conjugated π system via resonance (mesomerism) or inductive effects (or induction)—called +M or +I effects, respectively—thus making the π system more nucleophilic.

  3. Electron-withdrawing group - Wikipedia

    en.wikipedia.org/wiki/Electron-withdrawing_group

    Electron-withdrawing groups exert an "inductive" or "electron-pulling" effect on covalent bonds. The strength of the electron-withdrawing group is inversely proportional to the pKa of the carboxylic acid. [2] The inductive effect is cumulative: trichloroacetic acid is 1000x stronger than chloroacetic acid.

  4. Inductive effect - Wikipedia

    en.wikipedia.org/wiki/Inductive_effect

    In Organic chemistry, the inductive effect in a molecule is a local change in the electron density due to electron-withdrawing or electron-donating groups elsewhere in the molecule, resulting in a permanent dipole in a bond. [1] It is present in a σ (sigma) bond, unlike the electromeric effect which is present in a π (pi) bond.

  5. Mesomeric effect - Wikipedia

    en.wikipedia.org/wiki/Mesomeric_effect

    The mesomeric effect is negative (–M) when the substituent is an electron-withdrawing group, and the effect is positive (+M) when the substituent is an electron donating group. Below are two examples of the +M and –M effect. Additionally, the functional groups that contribute to each type of resonance are given below.

  6. Electronic effect - Wikipedia

    en.wikipedia.org/wiki/Electronic_effect

    When this center is an electron rich carbanion or an alkoxide anion, the presence of the electron-withdrawing substituent has a stabilizing effect. Similarly, an electron-releasing group (ERG) or electron-donating group (EDG) releases electrons into a reaction center and as such stabilizes electron deficient carbocations.

  7. Pi electron donor-acceptor - Wikipedia

    en.wikipedia.org/wiki/Pi_electron_donor-acceptor

    For pi-electron donating substituents like -NH 2, OH or -F the pEDA parameter is positive, and for pi-electron withdrawing substituents like -NO 2, -BH 2 or -CN the pEDA is negative. The pEDA scale was invented by Wojciech P. Oziminski and Jan Cz. Dobrowolski and the details are available in the original paper. [1]

  8. NanoPutian - Wikipedia

    en.wikipedia.org/wiki/Nanoputian

    NH 2 is an electron donating group, and NO 2 is an electron withdrawing group, which both direct bromination to the meta position relative to the NO 2 substituent. Addition of NaNO 2, H 2 SO 4, and EtOH removes the NH 2 substituent.

  9. Captodative effect - Wikipedia

    en.wikipedia.org/wiki/Captodative_effect

    The captodative effect is the stabilization of radicals by a synergistic effect of an electron-withdrawing substituent and an electron-donating substituent. [2] [3] The name originates as the electron-withdrawing group (EWG) is sometimes called the "captor" group, whilst the electron-donating group (EDG) is the "dative" substituent. [3]