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  2. 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]

  3. Rotamer - Wikipedia

    en.wikipedia.org/wiki/Rotamers

    The two have equal free energy; neither is more stable, so neither predominates compared to the other. A negative difference in free energy means that a conformer interconverts to a thermodynamically more stable conformation, thus the equilibrium constant will always be greater than 1.

  4. 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 ...

  5. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    The remainder of them were product molecules in the immediate past ([AB r] ‡). In TST, it is assumed that the flux of activated complexes in the two directions are independent of each other. That is, if all the product molecules were suddenly removed from the reaction system, the flow of [AB r] ‡ stops, but there is still a flow from left ...

  6. Cyclohexane conformation - Wikipedia

    en.wikipedia.org/wiki/Cyclohexane_conformation

    Cyclohexane is the most stable of the cycloalkanes, due to the stability of adapting to its chair conformer. [4] This conformer stability allows cyclohexane to be used as a standard in lab analyses. More specifically, cyclohexane is used as a standard for pharmaceutical reference in solvent analysis of pharmaceutical compounds and raw materials.

  7. Chemical stability - Wikipedia

    en.wikipedia.org/wiki/Chemical_stability

    In chemistry, chemical stability is the thermodynamic stability of a chemical system, in particular a chemical compound or a polymer. [1]Chemical stability may also refer to the shelf-life of a particular chemical compound; that is the duration of time before it begins to degrade in response to environmental factors.

  8. Ring flip - Wikipedia

    en.wikipedia.org/wiki/Ring_flip

    The conformer of methylcyclohexane with equatorial methyl is favored by 1.74 kcal/mol (7.3 kJ/mol) relative to the conformer where methyl is axial. In organic chemistry, a ring flip (also known as a ring inversion or ring reversal) is the interconversion of cyclic conformers that have equivalent ring shapes (e.g., from a chair conformer to ...

  9. Hammond's postulate - Wikipedia

    en.wikipedia.org/wiki/Hammond's_postulate

    At higher temperatures when microscopic reversal is easier, the more stable thermodynamic product is favored because these intermediates have time to rearrange. Whether run at high or low temperatures, the mixture of the kinetic and thermodynamic products eventually reach the same ratio, one in favor of the more stable thermodynamic product ...