Synthesis and crystal structure of [U(η-C8H8)]2[μ-η4:η4-HN(CH2)3N(CH2)2N(CH2)3NH], a dinuclear compound with a bridging tetra-amide ligand

The title compound was prepared by the transamination reaction of [U(COT)(N{SiMe3}2)2] and H2N(CH2)3NH(CH2)2NH(CH2)3NH2. The X-ray crystal structure reveals the shortest UU distance [3.3057(9) Å] ever observed in a molecular compound.