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  2. Eclipsed conformation - Wikipedia

    en.wikipedia.org/wiki/Eclipsed_conformation

    In chemistry an eclipsed conformation is a conformation in which two substituents X and Y on adjacent atoms A, B are in closest proximity, implying that the torsion angle X–A–B–Y is 0°. [1] Such a conformation can exist in any open chain, single chemical bond connecting two sp 3 - hybridised atoms, and it is normally a conformational ...

  3. Rotamer - Wikipedia

    en.wikipedia.org/wiki/Rotamer

    The staggered conformation is more stable by 12.5 kJ/mol than the eclipsed conformation, which is the energy maximum for ethane. In the eclipsed conformation the torsional angle is minimised. staggered conformation left, eclipsed conformation right in Newman projection

  4. Gauche effect - Wikipedia

    en.wikipedia.org/wiki/Gauche_effect

    The gauche effect is very sensitive to solvent effects, due to the large difference in polarity between the two conformers.For example, 2,3-dinitro-2,3-dimethylbutane, which in the solid state exists only in the gauche conformation, prefers the gauche conformer in benzene solution by a ratio of 79:21, but in carbon tetrachloride, it prefers the anti conformer by a ratio of 58:42. [9]

  5. Newman projection - Wikipedia

    en.wikipedia.org/wiki/Newman_projection

    The diagram takes staggered and eclipsed conformations, as well as gauche and anti interactions into account. A staggered projection appears to have the surrounding species equidistant from each other. This kind of conformation tends to experience both anti and gauche interactions. [5]

  6. Strain (chemistry) - Wikipedia

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

    Allylic methyl and ethyl groups are close together. Allylic strain, or A 1,3 strain is closely associated to syn-pentane strain. An example of allylic strain can be seen in the compound 2-pentene. It's possible for the ethyl substituent of the olefin to rotate such that the terminal methyl group is brought near to the vicinal methyl group of ...

  7. Methyl group - Wikipedia

    en.wikipedia.org/wiki/Methyl_group

    The oxidation products derived from methyl are hydroxymethyl group −CH 2 OH, formyl group −CHO, and carboxyl group −COOH. For example, permanganate often converts a methyl group to a carboxyl (−COOH) group, e.g. the conversion of toluene to benzoic acid. Ultimately oxidation of methyl groups gives protons and carbon dioxide, as seen in ...

  8. Hyperconjugation - Wikipedia

    en.wikipedia.org/wiki/Hyperconjugation

    Hyperconjugation can be used to rationalize a variety of chemical phenomena, including the anomeric effect, the gauche effect, the rotational barrier of ethane, the beta-silicon effect, the vibrational frequency of exocyclic carbonyl groups, and the relative stability of substituted carbocations and substituted carbon centred radicals, and the thermodynamic Zaitsev's rule for alkene stability.

  9. Ring flip - Wikipedia

    en.wikipedia.org/wiki/Ring_flip

    The molecular motions involved in a chair flip are detailed in the figure on the right: The half-chair conformation (D, 10.8 kcal/mol, C 2 symmetry) is the energy maximum when proceeding from the chair conformer (A, 0 kcal/mol reference, D 3d symmetry) to the higher energy twist-boat conformer (B, 5.5 kcal/mol, D 2 symmetry).