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  2. Ring strain - Wikipedia

    en.wikipedia.org/wiki/Ring_strain

    In some molecules, torsional strain can contribute to ring strain in addition to angle strain. One example of such a molecule is cyclopropane. Cyclopropane's carbon-carbon bonds form angles of 60°, far from the preferred angle of 109.5° angle in alkanes, so angle strain contributes most to cyclopropane's ring strain. [10]

  3. Cyclopropane - Wikipedia

    en.wikipedia.org/wiki/Cyclopropane

    The small size of the ring creates substantial ring strain in the structure. Cyclopropane itself is mainly of theoretical interest but many of its derivatives - cyclopropanes - are of commercial or biological significance. [3] Cyclopropane was used as a clinical inhalational anesthetic from the 1930s through the 1980s. The substance's high ...

  4. Cycloalkane - Wikipedia

    en.wikipedia.org/wiki/Cycloalkane

    Ring strain is highest for cyclopropane, in which the carbon atoms form a triangle and therefore have 60° C–C–C bond angles. There are also three pairs of eclipsed hydrogens. The ring strain is calculated to be around 120 kJ mol −1.

  5. Strain (chemistry) - Wikipedia

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

    The strain energy of cyclopropane and cyclobutane are 27.5 and 26.3 kcal mol −1, respectively. [1] Cyclopentane experiences much less strain, mainly due to torsional strain from eclipsed hydrogens: its preferred conformations interconvert by a process called pseudorotation. [4]: 14 Ring strain can be considerably higher in bicyclic systems.

  6. Cyclopropanes - Wikipedia

    en.wikipedia.org/wiki/Cyclopropanes

    Most cyclopropanes are not prepared from the parent cyclopropane, which is somewhat inert. Cyclopropyl groups are often prepared by cyclization of 1,3-difunctional alkanes . An example of the former, cyclopropyl cyanide is prepared by the reaction of 4- chlorobutyronitrile with a strong base . [ 1 ]

  7. Activation of cyclopropanes by transition metals - Wikipedia

    en.wikipedia.org/wiki/Activation_of_cyclopro...

    Because of the large ring strain energy of cyclopropanes (29.0 kcal per mole), they are often used as substrates for C-C activation through oxidative addition of a transition metal into one of the three C-C bonds leading to a metallacyclobutane intermediate. Substituents on the cyclopropane affect the course of its activation. [3]

  8. Eclipsed conformation - Wikipedia

    en.wikipedia.org/wiki/Eclipsed_conformation

    A dihedral angle can indicate staggered and eclipsed orientation, but is specifically used to determine the angle between two specific atoms on opposing carbons. Different conformations have unequal energies, creating an energy barrier to bond rotation which is known as torsional strain. In particular, eclipsed conformations tend to have raised ...

  9. Bent bond - Wikipedia

    en.wikipedia.org/wiki/Bent_bond

    Bent bonds are found in strained organic compounds such as cyclopropane, oxirane and aziridine. In these compounds, it is not possible for the carbon atoms to assume the 109.5° bond angles with standard sp 3 hybridization. Increasing the p-character to sp 5 (i.e. 1 ⁄ 6 s-density and 5 ⁄ 6 p-density) [5] makes it possible to reduce the bond ...