Figure 5.

Space-filling models (90% Van der Waals radii) of the lowest-energy conformer of (R)-2 (right) and the second lowest-energy conformer of (R)-1 (left), and hypothetical structure of (R)-2 in the same conformation of (R)-1 (middle). In this latter, the atoms highlighted in yellow have short contacts (distance < sum of VdW radii), which are relieved by means of the rotations indicated by the blue arrows (leading to the lowest-energy structure on the right).