Effect of Polyelectrolyte Function on Helical Structures of Optically Active Poly(phenylacetylene) Derivatives Bearing Basic or Acidic Functional Pendant Groups

A study was conducted to demonstrate the effect of polyelectrolyte function on helical structures of optically active poly(phenylacetylene) derivatives bearing basic or acidic functional pendant groups. Three novel chiral-achiral random copolymers, (poly(10.9-co-50.1), (poly(2 0.9-co-50.1), and (poly(30.9-co-5 0.1) of phenylacetylene derivatives were synthesized. Cis-transoidal optically active copolymers bearing a basic diisopropylaminomethyl group and an acidic phosphonate monoethyl ester group were prepared by the copolymerization of diisopropylaminomethyl group with a rhodium catalyst. The optically active monomers were designed and synthesized by introducing the chiral substituents with a similar bulkiness to the achiral monomers in order to exclude the effect of the bulkiness during the copolymerization. The results revealed a significant contribution of the charged pendant groups that increased the δG r values, leading to remarkable amplification of the helical chirality by reduction of the helical reversal population.