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  2. Hyperconjugation - Wikipedia

    en.wikipedia.org/wiki/Hyperconjugation

    Hyperconjugation affects several properties. [6] [10]Bond length: Hyperconjugation is suggested as a key factor in shortening of sigma bonds (σ bonds). For example, the single CC bonds in 1,3-butadiene and propyne are approximately 1.46 Å in length, much less than the value of around 1.54 Å found in saturated hydrocarbons.

  3. Cieplak effect - Wikipedia

    en.wikipedia.org/wiki/Cieplak_Effect

    The Cieplak effect relies on the stabilizing interaction of mixing full and empty orbitals to delocalize electrons, known as hyperconjugation. [2] When the highest occupied molecular orbital of one system and the lowest unoccupied molecular orbital of another system have comparable energies and spatial overlap, the electrons can delocalize and sink into a lower energy level.

  4. Vinyl cation - Wikipedia

    en.wikipedia.org/wiki/Vinyl_cation

    C-H hyperconjugation is a significant factor because the C-H bond can significantly overlap with the vacant p-orbital. Another possible explanation is that smaller size of the hydrogen substituent allows solvation to take place more easily contributing more significant stabilization.

  5. Negative hyperconjugation in silicon - Wikipedia

    en.wikipedia.org/wiki/Negative_hyperconjugation...

    Negative hyperconjugation is a theorized phenomenon in organosilicon compounds, ... (CH 3) 3 moieties on C–H homo- and heterolysis. They, too, concluded that the β ...

  6. 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 ...

  7. Gauche effect - Wikipedia

    en.wikipedia.org/wiki/Gauche_effect

    In the hyperconjugation model, the donation of electron density from the CH σ bonding orbital to the C−F σ * antibonding orbital is considered the source of stabilization in the gauche isomer. Due to the greater electronegativity of fluorine, the CH σ orbital is a better electron donor than the C−F σ orbital, while the C−F σ ...

  8. Carbon–hydrogen bond activation - Wikipedia

    en.wikipedia.org/wiki/Carbon–hydrogen_bond...

    In organic chemistry and organometallic chemistry, carbon–hydrogen bond activation (CH activation) is a type of organic reaction in which a carbon–hydrogen bond is cleaved and replaced with a C−X bond (X ≠ H is typically a main group element, like carbon, oxygen, or nitrogen).

  9. Three-center two-electron bond - Wikipedia

    en.wikipedia.org/wiki/Three-center_two-electron_bond

    This bonding pattern is also seen in trimethylaluminium, which forms a dimer Al 2 (CH 3) 6 with the carbon atoms of two of the methyl groups in bridging positions. This type of bond also occurs in carbon compounds, where it is sometimes referred to as hyperconjugation; another name for asymmetrical three-center two-electron bonds.