Pyrrophens: Pyrrole-Based Hexadentate Ligands Tailor-Made for Uranyl (UO) Coordination and Molecular Recognition.

Derivatives of a novel pyrrole-containing Schiff base ligand system (called "pyrrophen") are presented which feature substituted phenylene linkers (R = R = H (); R = R = CH ()) and a binding pocket modeled after macrocyclic species. These ligands bind neutral CHOH in the solid state through pyrrolic hydrogen-bonding. The interaction of the uranyl cation (UO) and yields planar hexagonal bipyramdial uranyl complexes, while the Cu and Zn complexes were found to self-assemble as dinuclear helicate complexes (ML) with under identical conditions.