Exact helical polymer synthesis by directionally fixed connection of a C_2-chiral 9,9'-spirobifluorene unit with a C_2- or C_s-symmetric unit

摘要

Two types of exact helical polymers, screw-shaped and coil-shaped, consisting of right-angled C_2-chiral 9,9'-spirobifluorene skeletons were selectively synthesized based on a two-point-connection protocol by controlling the connecting direction between the monomers.