One-dimensional chain structures of hexanuclear uranium(iv) clusters bridged by formate ligands

Abstract

Three one-dimensional chain structures of uranium(iv) hexanuclear clusters have been synthesized under hydrothermal/solvothermal conditions.

Synthesis, Characterization, and Solid-State Structural Chemistry of Uranium(IV) Aliphatic Dicarboxylates

“…Indeed, to the best of our knowledge, only one other U­(IV) glutarate phase has been reported in the solid state, and it consists of a ligand-decorated hexamer . In fact, the hexamer is the most widely reported polynuclear species in actinide­(IV) structural chemistry and has been isolated with a wide variety of ligands including simple monocarboxylates (formate, acetate, chloroacetate, glycine) ,,, and polycarboxylates ,,, (terephthalates, fumarate, DOTA). Interestingly, in U-3 , the difunctional ligands result in the propagation of the hexanuclear entities into an extended three-dimensional network.…”

“…Yet, using the adipate, the U 6 clusters are instead linked into 1D chains, likely due to the increased flexibility of the six-carbon adipate as compared to succinate. To the best of our knowledge, such ligand-bridged one-dimensional chains of hexamers have only been reported for formate . Of particular interest is the linearly bridging water molecule (O7).…”

“…The goals of this work are to further examine the effects of hydrolysis and condensation, ligand complexation, and solution conditions on actinide phase formation through a systematic study of U­(IV) complexation by aliphatic dicarboxylates. To date, most studies have focused on either small, monanionic ligand sets (i.e., formate, − acetate, and simple amino acids , ) or those with rigid, aromatic backbones (i.e, benzoates, , pyridinedicarboxylates, terephthalates, , and furoates). Moving away from these monoanionic and/or rigid, aromatic linkers, the coordination of aliphatic dicarboxylates with U­(IV) was examined under room temperature conditions.…”

Time-controlled synthesis of the 3D coordination polymer U(1,2,3-Hbtc)2 followed by the formation of molecular poly-oxo cluster {U14} containing hemimellitate uranium(iv)

“…S6 †) exhibits a typical signature for the U(IV). The different 29,48 ). The X-ray thermodiffractogram of the washed compound 1 (Fig.…”

“…40,41 Such clusters were also characterized in the solid-state for the heavier 5f elements, such as Np(IV) 40,42 or Pu(IV). 40,[43][44][45][46] It has been also reported that monotopic ligands may also act as a bidentate linker between isolated [UO 8 ] unit (with acetate) 47 or hexanuclear [U 6 O 8 ] unit with formate 48 to generate one-dimensional chain structure.…”