Combined reversible switching of ECD and quenching of CPL with chiral fluorescent macrocycles.

Straightforward synthesis and resolution of a series of chiral fluorescent macrocycles are presented, together with their electronic circular dichroism (ECD), strong excimer fluorescence (EF, 300 to 650 nm) and allied highly circularly polarized luminescence (CPL, g(lum) up to 1.7 x 10(-2)). The ECD, EF and CPL responses are strongly affected by the presence of metal ions (Na+, Ba2+) thanks to deep conformational changes. While ECD signals can be almost completely reversibly inverted upon the complexation/decomplexation of metal ions in a typical binary response, CPL signals are reversibly quenched concomitantly. The designed macrocycles display thus a remarkable combination of both +/- ECD and on/off CPL reversible switching.