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Two‐electron oxidative addition is one of the most important elementary reactions for d‐block transition metals but it is uncommon for f‐block elements. Here, we report the first examples of intermolecular oxidative addition of E−H (E=C, N) bonds to uranium(II) centers. The transient U(II) species was formed in‐situ by reducing a heterometallic cluster featuring U(IV)‐Pd(0) bonds with potassium‐graphite (KC8). Oxidative addition of C−H or N−H bonds to the U(II) centers was observed when this transient U(II) species was treated with benzene, carbazole or 1‐adamantylamine, respectively. The U(II) centers could also react with tetracene, biphenylene or N2O, leading to the formation of arene reduced U(IV) products and uranyl(VI) species via two‐ or four‐electron processes. This study demonstrates that the intermolecular two‐electron oxidative addition reactions are viable for actinide elements. [ABSTRACT FROM AUTHOR]

Periodically arranging coordination‐distinct actinides into one crystalline architecture is intriguing but of great synthetic challenge. We report a rare example of a heterobimetallic actinide metal–organic framework (An‐MOF) by a unique reaction‐induced preorganization strategy. A thorium MOF (SCU‐16) with the largest unit cell among all Th‐MOFs was prepared as the precursor, then the uranyl was precisely embedded into the MOF precursor under oxidation condition. Single crystal of the resulting thorium‐uranium MOF (SCU‐16‐U) shows that a uranyl‐specific site was in situ induced by the formate‐to‐carbonate oxidation reaction. The heterobimetallic SCU‐16‐U exhibits multifunction catalysis properties derived from two distinct actinides. The strategy proposed here offers a new avenue to create mixed‐actinide functional material with unique architecture and versatile functionality. [ABSTRACT FROM AUTHOR]

Although examples of multiple bonds between actinide elements and main‐group elements are quite common, studies of the multiple bonds between actinide elements and transition metals are extremely rare owing to difficulties associated with their synthesis. Here we report the first example of molecular uranium complexes featuring a cis‐[M→→ ${{\rm{ \mathbin{{\stackrel{\textstyle\rightarrow} { {\smash{\rightarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ U←← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M] core (M=Rh, Ir), which exhibits an unprecedented arrangement of two M→→ ${{\rm{ \mathbin{{\stackrel{\textstyle\rightarrow} { {\smash{\rightarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ U double dative bond linkages to a single U center. These complexes were prepared by the reactions of chlorine‐bridged heterometallic complexes [{U{N(CH3)(CH2CH2NPiPr2)2}(Cl)2[(μ‐Cl)M(COD)]2}] (M=Rh, Ir) with MeMgBr or MeLi, a new method for the construction of species with U−M multiple bonds. Theoretical calculations including dispersion confirmed the presence of two U←← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M double dative bonds in these complexes. This study not only enriches the U←← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M multiple bond chemistry, but also provides a new opportunity to explore the bonding of actinide elements. [ABSTRACT FROM AUTHOR]

In the past decade, the area of solid state chemistry of actinides has witnessed a rapid development in China, based on the significantly increased proportion of the number of actinide containing crystal structures reported by Chinese researchers from only 2% in 2010 to 36% in 2021. In this review article, we comprehensively overview the synthesis, structure, and characterizations of representative actinide solid compounds including oxo-compounds, organometallic compounds, and endohedral metallofullerenes reported by Chinese researchers. In addition, Chinese researchers pioneered several potential applications of actinide solid compounds in terms of adsorption, separation, photoelectric materials, and photo-catalysis, which are also briefly discussed. It is our hope that this contribution not only calls for further development of this area in China, but also arouses new research directions and interests in actinide chemistry and material sciences. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: We present a new method for generating europium oxalate compounds by decomposing of N‐methyl 2‐pyrrolidone in HNO3 media. The reaction exhibits high selectivity towards Eu3+ over UO22+, which suggests that these conditions could be applied to a selective crystallization based separation system for trivalent lanthanides and hexavalent actinides. In this work, a new method for the separation of trivalent Eu3+ and hexavalent UO22+ in initial high‐acidity HNO3 solution is presented. N‐Methyl 2‐pyrrolidone was added in the HNO3 solution where Eu3+ and UO22+ coexisted, then the solution was heated. Eu3+ will react with oxalic acid and dimethylamine produced by N‐methyl 2‐pyrrolidone and form compound NH2(CH3)2[Eu(C2O4)2(H2O)], while UO22+ remains in the solution. This method provide a new strategy for separation of trivalent Eu3+ and hexavalent UO22+. [ABSTRACT FROM AUTHOR]

We present a depleted uranium-based metal organic framework, UO2(C8H3O6N)·DMF, that exhibits highly sensitive and selective detection towards Fe3+ ions in aqueous media with an extremely low detection limit of 6.3 ppb. This work offers insight into exploring the potential applications of actinide-based metal organic frameworks in the area of chemical sensing with intrinsic advantages of high selectivity and sensitivity. [ABSTRACT FROM AUTHOR]

Three thorium(iv)-based metal–organic hybrid compounds with 2D layered and 3D framework structures exhibiting graphene-like (6,3) sheet topologies were prepared with linkers with threefold symmetry. These compounds contain rare and relatively anisotropic coordination environments for low-valent actinides that are similar to those often observed for high-valent actinide ions. [ABSTRACT FROM AUTHOR]

Dissimilatory metal-reducing bacteria (DMRB) can harvest energy for growth and activities by respiring metals, but it is so far unknown whether DMRB can acquire crystalline-phase actinides. In the present study, we used Shewanella oneidensis MR-1 to investigate microbially-mediated dissolution and reduction of U(VI) in three uranyl(VI) borate and boronate crystals (i.e., UO 2 (CH 3 BO 2 )(H 2 O) (UCBO); UO 2 B 2 O 4 (UBO); and Na[(UO 2 )B 6 O 10 (OH)]·2H 2 O (NaUBO)). Comparison of the dissolved U(VI) concentrations between samples with and without bacteria indicates that MR-1 facilitated dissolution of UCBO and UBO. Based on the assumption that only dissolved U(VI) was reduced, U(VI) reduction was substantially underestimated for UCBO and NaUBO, indicating that MR-1 directly reduced crystalline U(VI) in these two compounds. Laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis implied that interactions occurred between microbial ligands and the residual particles of uranyl compounds. We found that S. oneidensis MR-1 can mediate the dissolution and reduction of crystalline U(VI) through facilitated dissolution and consequent reduction of crystals or direct reduction of U(VI) in crystals. These results help evaluate the environmental fate of solid-phase U(VI), critical for predicting U transport and remediating U-contaminated sites. [ABSTRACT FROM AUTHOR]

A Np(V) compound containing three-center cation-cation interations, K(NpO2)3(H2O)Cl4, has been prepared by reacting Np(V) with KCl in molten boric acid. This compound forms a three-dimensional channel structure that is constructed from both two- and three-center cation-cation interactions. Three new bonding modes for cation-cation interactions are added to the summary of all known Np(V) compounds. [ABSTRACT FROM AUTHOR]