Supramolecular polymers containing terpyridine-metal complexes in the side chain

The synthesis of supramolecular polymers containing metal complexes in the side chain is described. Atom transfer radical polymerization (ATRP) was used to synthesize the macromolecular backbone, and the metal complex was attached via postpolymerization chemistry. Homopolymers containing [Ru(terpy)(2)](2+) in the side chain were prepared in which the complex contained either a long hydrophobic C-16 alkyl group or only hydrogen at the 4'-position. The homopolymers containing the long C-16 alkyl groups showed lyotropic liquid crystalline (LC) behavior in chloroform solutions from room temperature to 60 degrees C and self-assembled in the bulk to form hexagonal arrays of cylinders. In addition, this alkyl side chain was observed to crystallize in the solid state. Homopolymers without the C-16 alkyl group showed no lyotropic LC or any crystallization behavior. The material design emphasizes the relationship between the molecular structure and supramolecular organization of these polymers. It demonstrates that terpy complexes remain a versatile functionality for constructing supramolecular assemblies.