Uranyl(VI) Triflate as Catalyst for the Meerwein-Ponndorf-Verley Reaction

Design of Promising Uranyl(VI) Complexes Thin Films with Potential Applications in Molecular Electronics

In this work, it is proposed the development of organic semiconductors (OS) based on uranyl(VI) complexes. The above by means of the synthesis and the characterization of the complexes by Infrared spectroscopy, Nuclear magnetic resonance spectroscopy, mass spectrometry, and X-ray diffraction. Films of these complexes were deposited and subsequently, topographic and structural characterization was carried out by Scanning Electron Microscopy, X-ray diffraction, and Atomic Force Microscopy. Additionally, the nanomechanical evaluation was performed to know the stiffness of uranyl films using their modulus of elasticity. Also, the optical characterization took place in the devices and their bandgap value ranges between 2.40 and 2.93 eV being the minor for the film of the uranyl complex with the N on pyridine in position 4 (2 c). Finally, the electrical behavior of the uranyl(VI) films was evaluated, and important differences were obtained: the uranyl complex with the N on pyridine in position 2 (2 a) film is not influenced by changes in lighting and its current density is in the order of 10-3 A/cm2. The film with uranyl complex with the N on pyridine in position 3 (2 b) and 2 c presents a greater current flow under lighting conditions and two orders of magnitude larger than in film 2 a. In these films 2 b and 2 c, ohmic behavior occurs at low voltages, while at high voltages the charge transport changes to space-charge limited current behavior.

Photochemical separation of plutonium from uranium

Plutonium-based technologies would benefit if chemical hazards for purifying plutonium were reduced. One critical processing step where improvements could be impactful is the adjustment of plutonium oxidation-states during separations. This transformation often requires addition of redox agents. Unfortunately, many of the redox agents used previously cannot be used today because their properties are deemed incompatible with modern day processing facilities and waste stream safety requirements. We demonstrated herein that photochemistry can be used as an alternative to those chemical agents. We observed that (1) Pu⁴⁺ → Pu³⁺ and UO₂²⁺ → U⁴⁺ photoreduction proceeded in HCl_(aq) and HNO_3(aq) and (2) photogenerated Pu³⁺_(aq) and U⁴⁺_(aq) could be separated using anion exchange chromatography (high yield, >90%; good separation factor, 322).

Base-free transfer hydrogenation of aldehydes and ketones catalyzed by imidazolin-2-iminato actinide complexes

A series of thorium and uranium complexes decorated with unsymmetrical imidazolin-2-iminato ligands were found to be effective as catalysts in the transfer hydrogenation of aldehydes and ketones with 2-propanol to form the corresponding alcohols.