Amplified Chirality Transfer to Aromatic Molecules through Non‐specific Inclusion by Amorphous, Hyperbranched Poly(fluorenevinylene) Derivatives

Optically active, hyperbranched, poly(fluorene-2,4,7-triylethene-1,2-diyl) [poly(fluorenevinylene)] derivatives bearing a neomenthyl group and a pentyl group at the 9-position of fluorene backbone at various ratios as chirality donor (host polymers) efficiently included naphthalene, anthracene, pyrene, 9-phenylanthracene, and 9,10-diphenyanthracene as chirality acceptor (guest molecules) in their interior space in film as well as in solution, and the guest molecules exhibited intense circular dichroism through chirality transfer with chirality amplification. Chirality transfer efficiency was much higher with higher-molar-mass polymers than lower-molar-mass ones and with hyperbranched polymers than the analogous linear ones. The hyperbranched polymers include the small molecules in their complex structure without any specific interactions at flexible stoichiometry. The included molecules may have ordered intermolecular arrangement that may be somewhat similar to those of liquid crystals. Naphthalene, anthracene, and pyrene included in the polymer exhibited efficient circularly polarized luminescence where chirality was remarkably amplified in excited states, and anthracene exhibited especially high anisotropies in emission of the order of 10-2.