A chiral poly(para-phenyleneethynylene) (PPE) derivative

We have investigated the chiroptical properties of novel PPEs containing chiral side chains. The synthesis of poly(2,5-bis[2-(S)-methylbutoxy]-1,4-phenyleneethynylene) (BMB-PPE) was achieved in a Heck-type aryl-aryl cross coupling (M _n = 10 000, D_p = 40). The very good solubility of BMB-PPE allows for a detailed study of its chiroptical properties. Our studies demonstrate that the bisignated CD spectra of BMB-PPE are associated with an intermolecular aggregation phenomena.