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  2. 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 ...

  3. 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.

  4. Stereoisomerism - Wikipedia

    en.wikipedia.org/wiki/Stereoisomerism

    The conformational inversion of substituted cyclohexanes is a very rapid process at room temperature, with a half-life of 0.00001 seconds. [ 14 ] There are some molecules that can be isolated in several conformations, due to the large energy barriers between different conformations. 2,2',6,6'-Tetrasubstituted biphenyls can fit into this latter ...

  5. Cis–trans isomerism - Wikipedia

    en.wikipedia.org/wiki/Cis–trans_isomerism

    Cis and trans isomers occur both in organic molecules and in inorganic coordination complexes. Cis and trans descriptors are not used for cases of conformational isomerism where the two geometric forms easily interconvert, such as most open-chain single-bonded structures; instead, the terms " syn " and " anti " are used.

  6. Carbohydrate conformation - Wikipedia

    en.wikipedia.org/wiki/Carbohydrate_conformation

    The chair conformation of six-membered rings have a dihedral angle of 60° between adjacent substituents thus usually making it the most stable conformer. Since there are two possible chair conformation steric and stereoelectronic effects such as the anomeric effect, 1,3-diaxial interactions, dipoles and intramolecular hydrogen bonding must be taken into consideration when looking at relative ...

  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. 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

  9. Staggered conformation - Wikipedia

    en.wikipedia.org/wiki/Staggered_conformation

    Staggered conformation image right in Newman projection Eclipsed conformation. In organic chemistry, a staggered conformation is a chemical conformation of an ethane-like moiety abcX–Ydef in which the substituents a, b, and c are at the maximum distance from d, e, and f; this requires the torsion angles to be 60°. [1]