Novel π-conjugated cyclophane polymers containing phenylamine moieties with strong blue-light emission

Novel through-space conjugated polymers based on poly(p-phenylene-ethynylene) (PPE) containing alternate [2.2]paracyclophane and phenylamine moieties in the main chain were synthesized by the Sonogashira coupling reaction. Polymers were soluble in common organic solvents, and transparent and uniform thin films of the polymers were obtained easily by casting or spin-coating from toluene solution. According to the UV-vis absorption spectra, π-electrons of the polymer were delocalized via the through-space interaction between the two benzene rings in the cyclophane unit. The polymer exhibited strong blue emission in solution and in the solid state.