Figure 4.16 (a) Carbon skeleton and (b) line drawing of the twist conformation of
cyclohexane.
- The energy barrier between the chair, boat, and twist conformations of
cyclohexane are low enough to make separation of the conformers impossible at
room temperature.
- Because of the greater stability of the chair, more than 99% of the
molecules are estimated to be in a chair conformation at any given moment.
Figure 4.17 The relative energies of the various conformations of cyclohexane.
The positions of maximum energy are conformations called half-chair
conformations, in which the carbon atoms of one end of the ring have
become coplanar.