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Abstract Herein, we report the first systematic study of the oxidative addition of aryl bromides to a Pd^Icenter to generate organometallic Pd^IIIcomplexes. These isolable Pd^IIIcomplexes stabilized by tetradentate macrocyclic pyridinophane ligands exhibit distinct UV–vis and EPR spectroscopic signatures that allowed for the monitoring of their generation in situ. These ligand scaffolds were sterically and electronically tuned using a modular synthetic approach to probe the kinetic properties and activation parameters of the oxidative addition reaction, and a combination of UV–vis and cryo stopped‐flow spectroscopic studies reveal a rapid oxidative addition step occurring at a Pd^Icenter. In addition, these results are in strong agreement with our recent reactivity studies, which demonstrated that mononuclear Pd^Isystems are competent catalysts in Kumada cross‐coupling reactions, and thus set the stage for an improved understanding of potential catalytic applications for odd‐electron Pd systems. 

An isolated Ni( ii )-nitrosyl complex supported by the bulky tridentate 1,4,7-triisopropyl-1,4,7-triazacyclononane (iPr 3 TACN) ligand was obtained from the reaction of a Ni( ii ) dimethyl complex with NOPF 6 , suggesting the in situ formation of a Ni( i ) species that reacts with the resulting NO product. Use of a π-acceptor ancillary isocyanide ligand led to the isolation and characterization of an uncommon 5-coordinate Ni( i ) complex supported by the iPr 3 TACN ligand and tert -butylisocyanide. 

Methods for the straightforward, room temperature synthesis of UO 2+ x nanoparticles and thin films using solution processable, molecular uranium( iv ) compounds is described. Ultra-small uranium dioxide nanoparticles are synthesized from the hydrolysis of either U(ditox) 4 (ditox = − OCH t Bu 2 ) (1) or U(CH 2 SiMe 2 NSiMe 3 )[N(SiMe 3 ) 2 ] 2 (2) via addition of water to stirring solutions of the compounds in non-polar solvents to give UO 2 -1 and UO 2 -2, respectively. The structural characteristics of the uranium dioxide nanoparticles were characterized using powder X-ray diffraction (pXRD), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. The pXRD results affirm the cubic fluorite structure expected for UO 2 nanoparticles. The nanocrystallinity of UO 2 -1 and UO 2 -2 were substantiated by bright-field HRTEM images and fast Fourier transform (FFT) patterns. The HRTEM analysis also shows the nanoparticles fall within the ultra-small regime possessing sizes of ∼3 nm with uniform distribution. Additionally, we demonstrate the versatility of 1 as a uranium dioxide precursor, showing that it can be readily sublimed onto glass or silicon substrates and subsequently hydrolyzed to give UO 2+ x thin films.