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  2. A value - Wikipedia

    en.wikipedia.org/wiki/A_value

    One can use steric hindrances to determine the propensity of a substituent to reside in the axial or equatorial plane. It is known that axial bonds are more hindered than the corresponding equatorial bonds. This is because substituents in the axial position are relatively close to two other axial substituents.

  3. Anomeric effect - Wikipedia

    en.wikipedia.org/wiki/Anomeric_effect

    The α- and β-anomers of D-glucopyranose.. In organic chemistry, the anomeric effect or Edward-Lemieux effect (after J. T. Edward and Raymond Lemieux) is a stereoelectronic effect that describes the tendency of heteroatomic substituents adjacent to the heteroatom in the ring in, e.g., tetrahydropyran to prefer the axial orientation instead of the less-hindered equatorial orientation that ...

  4. Bent's rule - Wikipedia

    en.wikipedia.org/wiki/Bent's_rule

    Trigonal bipyramid molecules have both with axial and equatorial positions. If there are two types of substituents, the more electronegative substituent will prefer the axial position as there are smaller bond angles between axial and electronegative substituents than between two equatorial substituents.

  5. Molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Molecular_geometry

    The position of each atom is determined by the nature of the chemical bonds by which it is connected to its neighboring atoms. The molecular geometry can be described by the positions of these atoms in space, evoking bond lengths of two joined atoms, bond angles of three connected atoms, and torsion angles (dihedral angles) of three consecutive ...

  6. 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.

  7. Apicophilicity - Wikipedia

    en.wikipedia.org/wiki/Apicophilicity

    Apicophilicity is the phenomenon in which electronegative substituents of trigonal bipyramidal pentacoordinate compounds prefer to occupy apical (axial) positions (L ap). [1] The term "apicophilicity" was first proposed by Earl L. Muetterties in 1963 for the structural analysis of pentacoordinate phosphorus fluorides by 19 F NMR.

  8. VSEPR theory - Wikipedia

    en.wikipedia.org/wiki/VSEPR_theory

    [1]: 410–417 For instance, when 5 valence electron pairs surround a central atom, they adopt a trigonal bipyramidal molecular geometry with two collinear axial positions and three equatorial positions. An electron pair in an axial position has three close equatorial neighbors only 90° away and a fourth much farther at 180°, while an ...

  9. Structural formula - Wikipedia

    en.wikipedia.org/wiki/Structural_formula

    Axial and equatorial positions are not distinguished; instead, substituents are positioned directly above or below the ring atom to which they are connected. Hydrogen substituents are typically omitted. However, an important thing to keep in mind while reading an Haworth projection is that the ring structures are not flat.