Poly(phenylacetylene) Amines: A General Route to Water-Soluble Helical Polyamines

Poly­(phenylacetylene)­s bearing prim- and sec-amine groups are barely known because of their poisoning activity toward the polymerization catalyst. Herein, we prepare 11 different amino polymers in high yields by direct polymerization of their corresponding ammonium salts in water using [Rh­(cod)₂]⁺BF₄^– as catalyst. They are stable, water-soluble, and show a helical structure that responds to external stimuli (polarity, pH, and metal ions) acting on the pendants. The location of the amino group in the pendant is shown to be critical for the helical response to protonation.