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  2. Electron-withdrawing group - Wikipedia

    en.wikipedia.org/wiki/Electron-withdrawing_group

    An electron-withdrawing group (EWG) is a group or atom that has the ability to draw electron density toward itself and away from other adjacent atoms. [1] This electron density transfer is often achieved by resonance or inductive effects.

  3. Electrophilic aromatic directing groups - Wikipedia

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

    The EWG removes electron density from a π system, making it less reactive in this type of reaction, [2] [3] and therefore called deactivating groups. EDGs and EWGs also determine the positions (relative to themselves) on the aromatic ring where substitution reactions are most likely to take place.

  4. Captodative effect - Wikipedia

    en.wikipedia.org/wiki/Captodative_effect

    The olefins contained an EWG nitrile group and varying EDGs and the effect of varying EDGs on the rate of the addition reactions was observed. The process studied was: The process studied was: The rate of the addition reaction was accelerated by the following EDGs in increasing order: H < CH 3 < OCH 2 CH 3 .

  5. 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.

  6. Electronic effect - Wikipedia

    en.wikipedia.org/wiki/Electronic_effect

    An electric effect influences the structure, reactivity, or properties of a molecule but is neither a traditional bond nor a steric effect. [1] In organic chemistry, the term stereoelectronic effect is also used to emphasize the relation between the electronic structure and the geometry (stereochemistry) of a molecule.

  7. Lewis acids and bases - Wikipedia

    en.wikipedia.org/wiki/Lewis_acids_and_bases

    For example, NH 3 is a Lewis base, because it can donate its lone pair of electrons. Trimethylborane [(CH 3 ) 3 B] is a Lewis acid as it is capable of accepting a lone pair. In a Lewis adduct, the Lewis acid and base share an electron pair furnished by the Lewis base, forming a dative bond. [ 1 ]

  8. Organic sulfide - Wikipedia

    en.wikipedia.org/wiki/Organic_sulfide

    Some sulfides are named by modifying the common name for the corresponding ether. For example, C 6 H 5 SCH 3 is methyl phenyl sulfide, but is more commonly called thioanisole, since its structure is related to that for anisole, C 6 H 5 OCH 3. The modern systematic nomenclature in chemistry for the trival name thioether is sulfane. [2]

  9. Horner–Wadsworth–Emmons reaction - Wikipedia

    en.wikipedia.org/wiki/Horner–Wadsworth–Emmons...

    Nucleophilic addition of the carbanion onto the aldehyde 2 (or ketone) producing 3a or 3b is the rate-limiting step. [12] If R 2 = H, then intermediates 3a and 4a and intermediates 3b and 4b can interconvert with each other. [13] The final elimination of oxaphosphetanes 4a and 4b yield (E)-alkene 5 and (Z)-alkene 6, with the by-product being a ...