Exploring Potentialities and Limitations of Stapled o- Oligo(PhenyleneEthynylene)s (o-OPEs) as Efficient Circularly Polarized Luminescence Emitters

Abstract

In this paper we have studied the chiroptical properties of a family of o-OPE derivatives with different steric hindrance. Experimental results show high dissymmetry factors (gabs and glum up to 1.1x10-2) and very similar ECD and CPL for all the derivatives, that makes this basic o-OPE scaffold a robust pure organic emitter. VCD spectra are used to characterize conformational properties in solution. DFT and TD-DFT calculations support experimental results also proving that ECD and CPL are almost exclusively linked to helical moiety and not to size or conformation of substituents. As chiroptical properties of these emitters are independent of substituents, this OPE scaffold can be used as basic skeleton for the design of sensing probes with high CPL efficiencies.