New polyester-based terpyridine-macroligands and their blue iron(II) complexes

A library of hydroxy- and amino-functionalized Kröhnke-type terpyridines have been used to synthesize new terpyridine end-functionalized poly(-caprolactone)s and poly(L-lactide)s, via Sn(II)-catalyzed ring-opening polymerization. It has also been possible to prepare a set of metallo-supramolecular AA homopolymers by complexation with Fe(II) metal ions. All of these complexes have been fully characterized. Stable metallo-polymers with an intense blue color have been obtained from the quaternized macroligands. This color property might be of great interest for the design of functional supramolecular materials, with respect to color tuning and optical applications.