When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Planar chirality - Wikipedia

    en.wikipedia.org/wiki/Planar_chirality

    Planar chirality, also known as 2D chirality, is the special case of chirality for two dimensions. Most fundamentally, planar chirality is a mathematical term, finding use in chemistry , physics and related physical sciences, for example, in astronomy , optics and metamaterials .

  3. Chirality (chemistry) - Wikipedia

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

    BINOL is a typical example of an axially chiral molecule, while trans-cyclooctene is a commonly cited example of a planar chiral molecule. Finally, helicene possesses helical chirality, which is one type of inherent chirality. Chirality is an important concept for stereochemistry and biochemistry.

  4. Chirality - Wikipedia

    en.wikipedia.org/wiki/Chirality

    Chirality (/ k aɪ ˈ r æ l ɪ t i /) is a property of asymmetry important in several branches of science. The word chirality is derived from the Greek χείρ (kheir), "hand", a familiar chiral object. An object or a system is chiral if it is distinguishable from its mirror image; that is, it cannot be superposed (not to be confused with ...

  5. Axial chirality - Wikipedia

    en.wikipedia.org/wiki/Axial_chirality

    Two types of molecules having axial chirality: allenes (left) and binaryl atropisomers (right) In chemistry, axial chirality is a special case of chirality in which a molecule contains two pairs of chemical groups in a non-planar arrangement about an axis of chirality so that the molecule is not superposable on its mirror image.

  6. Pillararene - Wikipedia

    en.wikipedia.org/wiki/Pillararene

    The orientation of the hydroquinone oxygens on both rims of the pillararene allow the macrocycle to exhibit planar chirality. When the substituent on the hydroquinone oxygen is small enough to fit through the cavity of the pillararene, allowing for oxygen-through-the-annulus rotation to occur, racemization occurs. If this substituent is large ...

  7. Ferrocene - Wikipedia

    en.wikipedia.org/wiki/Ferrocene

    A planar chiral ferrocene derivative. Disubstituted ferrocenes can exist as either 1,2-, 1,3- or 1,1′- isomers, none of which are interconvertible. Ferrocenes that are asymmetrically disubstituted on one ring are chiral – for example [CpFe(EtC 5 H 3 Me)]. This planar chirality arises despite no single atom being a stereogenic centre.

  8. Pyramidal inversion - Wikipedia

    en.wikipedia.org/wiki/Pyramidal_inversion

    [1] [2] It is a rapid oscillation of the atom and substituents, the molecule or ion passing through a planar transition state. [3] For a compound that would otherwise be chiral due to a stereocenter, pyramidal inversion allows its enantiomers to racemize.

  9. Ugi's amine - Wikipedia

    en.wikipedia.org/wiki/Ugi's_amine

    Nozaki, et al. demonstrated that a ferrocene derivative bearing a chiral amine substituent could participate in directed ortho lithiation of the same ring of the ferrocene, yielding products with planar chirality diastereoselectively. [5] Nozaki’s ferrocene derivative provided products that were only 86% optically pure.