Ring-Opening Polymerization of a Strained [3]Nickelocenophane: A Route to Polynickelocenes, a Class of S=1 Metallopolymers

We report the synthesis, reactivity studies, and ring-opening polymerization of a tricarba[3]nickelocenophane. The resulting green polynickelocene (5) possesses a -(CH2)(3)- spacer between the nickelocene units and is shown to be of high molecular weight. SQUID magnetometry measurements indicate that 5 is a macromolecular material with an S = 1 repeat unit.