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  2. Cyclohexane conformation - Wikipedia

    en.wikipedia.org/wiki/Cyclohexane_conformation

    Cis-1,4-Di-tert-butylcyclohexane has an axial tert-butyl group in the chair conformation and conversion to the twist-boat conformation places both groups in more favorable equatorial positions. As a result, the twist-boat conformation is more stable by 0.47 kJ/mol (0.11 kcal/mol) at 125 K (−148 °C) as measured by NMR spectroscopy. [9]

  3. Cyclohexane - Wikipedia

    en.wikipedia.org/wiki/Cyclohexane

    The chair and twist-boat are energy minima and are therefore conformers, while the half-chair and the boat are transition states and represent energy maxima. The idea that the chair conformation is the most stable structure for cyclohexane was first proposed as early as 1890 by Hermann Sachse, but only gained widespread acceptance much later.

  4. 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.

  5. Rotamer - Wikipedia

    en.wikipedia.org/wiki/Rotamer

    The repulsion between an axial t-butyl group and hydrogen atoms in the 1,3-diaxial position is so strong that the cyclohexane ring will revert to a twisted boat conformation. The strain in cyclic structures is usually characterized by deviations from ideal bond angles ( Baeyer strain ), ideal torsional angles ( Pitzer strain ) or transannular ...

  6. Structural formula - Wikipedia

    en.wikipedia.org/wiki/Structural_formula

    There is a peak/local maximum at the boat conformation (C), and there are valleys/local minimums at the twist-boat conformations (B). In addition, cyclohexane conformations can be used to indicate if the molecule has any 1,3 diaxial-interactions which are steric interactions between axial substituents on the 1,3, and 5 carbons. [7]

  7. Florida woman gives insane excuse for why she snatched 3-year ...

    www.aol.com/news/florida-woman-flimsy-excuse-why...

    A Florida woman who allegedly snatched a three-year-old boy from his fenced-in yard and ran off down the street last week told the cops she shouldn’t be arrested because she “gave it back ...

  8. Allylic strain - Wikipedia

    en.wikipedia.org/wiki/Allylic_strain

    Several factors influence the energy penalty associated with the allylic strain. In order to relieve strain caused by interaction between the two methyl groups, the cyclohexanes will often exhibit a boat or twist-boat conformation. The boat conformation tends to be the major conformation to the strain. [2]

  9. The coronation of King Charles III and Queen Camilla held in May last year cost British taxpayers £72 million ($91 million), an amount some have labeled excessive.. The Department for Culture ...