On-off reversible switching of the chirality of one-handed helical Poly(phenylacetylene)s by polarity stimuli

A chiral phenylacetylene (1) having two hydroxy groups was synthesized by using an achiral catalytic system of [Rh(norbornadiene)Cl]2/triethylamine. This chiral monomer 1 was suitable to the asymmetric-induced polymerization to induce chirality in the main chain. The chirality itself of the resulting homopoly(1) in solution showed an on-off switching ability responding to the solvent polarity. The on-off switching of chirality was due to the...