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  2. Captodative effect - Wikipedia

    en.wikipedia.org/wiki/Captodative_effect

    The ethoxy and cyano groups are able to delocalize the radical ion in the transition state, thus stabilizing the radical center. The rate enhancement is due to the captodative effect. When R = H, the reaction has the largest energy of activation because the radical center is not stabilized by the captodative effect.

  3. Bent's rule - Wikipedia

    en.wikipedia.org/wiki/Bent's_rule

    Bent's rule predicts that, in order to stabilize the unshared, closely held nonbonding electrons, lone pair orbitals should take on high s character. On the other hand, an unoccupied (empty) nonbonding orbital can be thought of as the limiting case of an electronegative substituent, with electron density completely polarized towards the ligand ...

  4. Radical (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Radical_(chemistry)

    The hydroxyl radical, Lewis structure shown, contains one unpaired electron. Lewis dot structure of a Hydroxide ion compared to a hydroxyl radical. In chemistry, a radical, also known as a free radical, is an atom, molecule, or ion that has at least one unpaired valence electron.

  5. Markovnikov's rule - Wikipedia

    en.wikipedia.org/wiki/Markovnikov's_rule

    Free-radical intermediate is stabilized by hyperconjugation; adjacent occupied sigma C–H orbitals donate into the electron-deficient radical orbital. A new method of anti-Markovnikov addition has been described by Hamilton and Nicewicz, who utilize aromatic molecules and light energy from a low-energy diode to turn the alkene into a cation ...

  6. Homolysis (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Homolysis_(chemistry)

    Radicals decrease in stability as they are closer to the nucleus, because the electron affinity of the orbital increases. As a general rule, hybridizations minimizing s-character increase the stability of radicals, and decreases the bond dissociation energy (i.e. sp 3 hybridization is most stabilizing).

  7. Norrish reaction - Wikipedia

    en.wikipedia.org/wiki/Norrish_reaction

    On cleavage of the α-carbon bond from either state, two radical fragments are obtained. [3] The size and nature of these fragments depends upon the stability of the generated radicals; for instance, the cleavage of 2-butanone largely yields ethyl radicals in favor of less stable methyl radicals. [4] Norrish type I reaction

  8. Trivalent group 14 radicals - Wikipedia

    en.wikipedia.org/wiki/Trivalent_group_14_radicals

    A trivalent group 14 radical (also known as a trivalent tetrel radical) is a molecule that contains a group 14 element (E = C, Si, Ge, Sn, Pb) with three bonds and a free radical, having the general formula of R 3 E•. Such compounds can be categorized into three different types, depending on the structure (or equivalently the orbital in which ...

  9. Distonic ion - Wikipedia

    en.wikipedia.org/wiki/Distonic_ion

    Collisions between ions and uncharged molecules allow one to detect the location of the radical and charge site in order to confirm that the ion is not just a regular radical ion. [7] When a molecule is ionized and can structurally be classified as a distonic ion, the molecule's kinetics and thermodynamic properties have been greatly altered.