Chiral Compounds Without StereocentersFor example, the isomers which are shown by the following figure are different. The two
isomers cannot convert from one to another spontaneously because of restriction of rotation
of double bonds.
Figure 91
Other types of chiral compounds without stereocenters (like restriction of rotation of a single
bond because of steric hindrance) also exist. Consider the following example of the R and
S binol molecules:
Figure 92
Figure 93
The biphenyl C-C bond cannot rotate if the X and Y groups cause steric hindrance.
Figure 94
This compound exhibits spiral chirality.