More Stereoheadache

There are two kinds of chirality involved in this compound : atropisomerism( axial chirality) and point chirality. The first one occurs as the bond between the phenyl groups cannot freely rotate along with its substituents due to the presence of large ortho groups. An energy barrier prohibits that from happening and is large enough to make the resolution of the 2 enantiomers possible( using the right method). The nomenclature for this kind of enantiomers is still R/S using the CIP priority-rules and you can look up to find how. Also there are two stereogenic carbon atoms in the bicyclo[2,1,1]hexane substituents at the linkage with the phenyl groups. We can expect for one configuration of the phenyl groups, 4 combinations of configurations of the chiral carbon atoms (R,R), (S,S), (R,S), (S,R). That should result in a total of 8 different compounds, but the R[R,S] is identical with R[S,R] and so is S[R,S] with S[S,R]( we denote firstly the axial chirality and in brackets the carbon atoms' chirality].