Molecular and Crystal Structures of Uranyl Nitrate Coordination Polymers with Double-Headed 2-Pyrrolidone Derivatives.

Double-headed 2-pyrrolidone derivatives (DHNRPs) were designed and synthesized as bridging ligands for the efficient and selective separation of UO22+ from a HNO3 solution by precipitation. The building blocks, UO2(NO3)2 and DHNRPs, were successfully connected to form an infinite 1D coordination polymer. The solubility of [UO2(NO3)2(DHNRP)]n is no longer correlated to the hydrophobicity of the ligand but is exclusively governed by the ligand symmetry and packing efficiency. The newly designed DHNRP family can be used to establish a new spent nuclear fuel reprocessing scheme.