ABSTRACT
The various form(s) of the molecule leads to conformations of the molecule that are important for reactivity in chemical reactions and in biological systems. A conformation of a molecule is a spatial arrangement of the atoms in a molecule. There are many conformations that are interconverted by rotation about covalent single bonds. The collection of lowest energy rotamers for all the bonds in a molecule is the lowest energy conformation of the molecule, which is taken as the effective shape of the molecule. Chair cyclohexanes predominate as the major conformation of cyclohexane because the boat, half-chair, and twist boat conformations are much higher in energy. The staggered rotamers where the methyl groups of butane are proximal but not eclipsing are known as gauche conformations. Three-dimensional models are shown to make the actual conformation of each molecule more apparent.
