The chair conformation of cyclohexane is not rigid. It can convert to a boat conformation, and then to a new chair conformation in a process termed ring-flipping. In this process, one carbon flips to give the boat conformation, then the carbon on the opposite side of the ring flips to give a new chair conformation. When opposite carbons flip like this, all axial and equatorial bonds interconvert. In the structure below, the red hydrogens are axial and the blue hydrogens are equatorial. As you play the movie and the ring-flip occurs, the red hydrogens become equatorial and the blue hydrogens become axial. The energy barrier to this ring-flipping process is about 10.5 kcal/mol (44 kJ/mol), so it is fast at common temperatures. It occurs about 100,000 times per second at room temperature.
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You can reorient the molecule during the "movie" to get a better view |