Synthesis, structural characterization, and chiroptical properties of planarly and axially chiral boranils

2-Amino[2.2]paracyclophanereactswithsalicylaldehydeor2-hydroxyacetophenone to yield imines that then give access to a new series ofboranils (8b–d) upon complexation with BF2. These novel boron-containingcompounds display both planar and axial chiralities and were examined exper-imentally and computationally. In particular, their photophysical and chiropti-cal properties were studied and compared to newly prepared, simpler boranils(9a–d) exhibiting axial chirality only. Less sophisticated chiral architectureswere shown to demonstrate overall stronger circularly polarized luminescence(CPL) activity