W-Shaped π-Extended Double Undecabenzo[7]helicene

Abstract

A chiral W-shaped fully π-extended double [7]helicene (ED7H) has been synthesized and fully characterized. It displays fluorescence emission (λ_em = 636 nm) with a quantum yield (Φ_f) of 0.10. In comparison to its X-shaped and monomict π-extended [7]helicene analogues, enantiopure W-shaped ED7H exhibited superior chiral optical characteristics, including distinct circular dichroism signals from 400 to 650 nm, a good dissymmetric emission factor |g_lum| of 4 × 10^-3, and a circularly polarized luminescence brightness value B_CPL of 42 M^-1 cm^-1.