Sensing the conformational changes thanks to chirality
Résumé
Helicene molecules due to their uncommon properties are very attractive. We work on modifying the regular ortho-fused aromatic rings skeleton and designed the helicene-like compounds incorporating dibenzo[c]acridine motive (see Figure 1).1,2 Their intense chiroptical properties in solution have been studied by polarimetry, electronic circular dichroism (ECD) spectroscopy and CPL. We show that they are strongly modulated by small differences in the structure. Moreover, acidification leads to dramatical changes: ~50 nm red shift and CD/CPL sign inversion. In order to rationalize the chiroptical properties, quantum-chemical calculations were performed.