Uranium Chemistry: Identifying the Next Frontiers†.

While uranium is the most extensively studied actinide in terms of chemical properties, there remains much to be explored about its fundamental chemistry. Organometallic and organoactinide chemistry first emerged in the 1950s with research that found inspiration from transition-metal chemistry with the synthesis and characterization of uranocene, expanding new opportunities for organoactinide chemistry. Since then, a significant amount of research has pursued many avenues characterizing the fundamental nature of the f orbitals and their modes of bonding as well as their potential in catalysis.

Cerium(IV) Pyrasal Complexes: A pH-Dependent 8- to 10-Coordinate Cerium Chelate Switch.

In this work, five cerium(IV) complexes were synthesized, three of which were structural isomorphs from the same pyrasal ligand with the solid-state result identified by structural analysis dependent on the initial pH of the reaction solution and the temperature at which the reaction is performed. The ligands explored here are pyrasal ligands, which are Schiff-base ligands formed by the condensation of 2,3-diaminopyrazine and a salicylaldehyde derivative. Pyrasal ligands have weaker binding than other salophen-type ligands due to the electron-withdrawing effect of the nitrogen atoms contained within the pyrazine ring.