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Qualitative differences in the reactivity of trivalent lanthanide and actinide complexes have long been attributed to differences in covalent metal-ligand bonding, but there are few examples where thermodynamic aspects of this relationship have been quantified, especially with U

Tandem catalysts that perform two different organic transformations in a single pot are highly desirable because they enable rapid and efficient assembly of simple organic building blocks into more complex molecules. Many examples of tandem catalysis rely on metal-catalyzed reactions involving one or more metal complexes. Remarkably, despite surging interest in the development of chemically reactive (i. e., non-innocent) ligands, there are few examples of metal complexes that leverage ligand-centered reactivity to perform catalytic reactions in tandem with separate catalytic reactions at the metal. Here we report how multifunctional Pd complexes with triaminoborane-derived diphosphorus ligands, called TBDPhos, appear to facilitate borenium-catalyzed cycloaddition reactions at the ligand, and Pd-catalyzed Stille and Suzuki cross-coupling reactions at the metal. Both transformations can be accessed in one pot to afford rare examples of tandem catalysis using separate metal and ligand catalysis sites in a single complex.

A number of technologies would benefit from developing inorganic compounds and materials with specific electronic and magnetic exchange properties. Unfortunately, designing compounds with these properties is difficult because metal⋅⋅⋅metal coupling schemes are hard to predict and control. Fully characterizing communication between metals in existing compounds that exhibit interesting properties could provide valuable insight and advance those predictive capabilities. One such class of molecules are the series of Lindqvist iron-functionalized and hexavanadium polyoxovanadate-alkoxide clusters, which we characterized here using V K-edge X-ray absorption spectroscopy. Substantial changes in the pre-edge peak intensities were observed that tracked with the V 3d-electron count. The data also suggested substantial delocalization between the vanadium cations. Meanwhile, the FeIII cations were electronically isolated from the polyoxovanadate core.

We report the small-scale synthesis, isolated yield, single-crystal X-ray structure, 1H NMR solution spectroscopy /solid-state UV/Vis-nIR spectroscopy, and density functional theory (DFT)/ab initio wave function theory calculations on an Am3+ organometallic complex, [Am(C5Me4H)3] (1). This constitutes the first quantitative data on Am−C bonding in a molecular species.

Constraining σ3-P compounds in nontrigonal, entatic geometries has proven to be an effective strategy for promoting biphilic oxidative addition reactions more typical of transition metals. Although qualitative descriptions of the impact of structure and symmetry on σ3-P complexes have been proposed, electronic structure variations responsible for biphilic reactivity have yet to be elucidated experimentally. Reported here are P K-edge XANES data and complementary TDDFT calculations for a series of structurally modified P(N)3 complexes that both validate and quantify electronic structure variations proposed to give rise to biphilic reactions at phosphorus. These data are presented alongside experimentally referenced electronic structure calculations that reveal nontrigonal structures predicted to further enhance biphilic reactivity in σ3-P ligands and catalysts., NIH NIGMS (Grant GM114547), NSF (Grant CHE-1724505)

New lanthanide CVD precursors of stoichiometry Ln(H(3)BNMe(2)BH(3))(3) have been prepared, where Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu. The ligand is N,N-dimethylaminodiboranate, a new kind of multidentate borohydride. The structures of the Ln(H(3)BNMe(2)BH(3))(3) complexes are highly dependent on the size of the lanthanide ions: the coordination number decreases from Pr (CN = 14) to Sm (CN = 13) to Er (CN = 12) corresponding with the decrease in ionic radii. The Ln(H(3)BNMe(2)BH(3))(3) complexes are highly volatile and sublime at temperatures as low as 65 degrees C in vacuum. These complexes are useful CVD precursors; for example, Y(H(3)BNMe(2)BH(3))(3) has been used to deposit Y(2)O(3) on silicon at 300 degrees C by CVD using water as a coreactant.