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  2. Rotamer - Wikipedia

    en.wikipedia.org/wiki/Rotamer

    Rotation about single bond of butane to interconvert one conformation to another. The gauche conformation on the right is a conformer, while the eclipsed conformation on the left is a transition state between conformers. Above: Newman projection; below: depiction of spatial orientation.

  3. Curtin–Hammett principle - Wikipedia

    en.wikipedia.org/wiki/Curtin–Hammett_principle

    The Curtin–Hammett principle is a principle in chemical kinetics proposed by David Yarrow Curtin and Louis Plack Hammett.It states that, for a reaction that has a pair of reactive intermediates or reactants that interconvert rapidly (as is usually the case for conformational isomers), each going irreversibly to a different product, the product ratio will depend both on the difference in ...

  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. Conformation - Wikipedia

    en.wikipedia.org/wiki/Conformation

    Conformation generally means structural arrangement and may refer to: Conformational isomerism, a form of stereoisomerism in chemistry Carbohydrate conformation; Cyclohexane conformation; Protein conformation; Conformation activity relationship between the biological activity and the conformation or conformational changes of a biomolecule

  6. Stereoisomerism - Wikipedia

    en.wikipedia.org/wiki/Stereoisomerism

    For example, there exists a variety of Cyclohexane conformations (which cyclohexane is an essential intermediate for the synthesis of nylon–6,6) including a chair conformation where four of the carbon atoms form the "seat" of the chair, one carbon atom is the "back" of the chair, and one carbon atom is the "foot rest"; and a boat conformation ...

  7. Ring flip - Wikipedia

    en.wikipedia.org/wiki/Ring_flip

    The chair conformation minimizes both angle strain and torsional strain by having all carbon-carbon bonds at 110.9° and all hydrogens staggered from one another. [2] The conformational changes that occur in a cyclohexane ring flip take place over several stages. Structure D (10.8 kcal/mol) is the highest energy transition state of the process.

  8. Ramachandran plot - Wikipedia

    en.wikipedia.org/wiki/Ramachandran_plot

    Glycine has only a hydrogen atom for its side chain, with a much smaller van der Waals radius than the CH 3, CH 2, or CH group that starts the side chain of all other amino acids. Hence it is least restricted, and this is apparent in the Ramachandran plot for glycine (see Gly plot in gallery ) for which the allowable area is considerably larger.

  9. 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 ...