Applications of boroxide ligands in supporting small molecule activation by U(iii) and U(iv) complexes

Abstract

The boroxide ligand [OBAr2]− (Ar = Mes, Trip) is shown to be able to support both UIII and UIV centres for the first time.

Continuous Shape Measures Study of the Coordination Spheres of Actinide Complexes – Part 1: Low Coordination Numbers

“…With only one exception, the chelated structures close to the Berry pathway have either a tridentate calixarene ligand C (Scheme 2) that occupies the equatorial coordination sites of a TBPY [57] or a bidentate ligand that forms six-or sevenmember chelate rings spanning an equatorial and an axial position. [58,59] It must be noticed that most of the Berry structures concentrate in the proximity of the trigonal bipyramid, with only one structure beyond 50 % along the path to the square pyramid (Figure 9b). [58] The non-Berry structures, on the other hand, are widely spread throughout the shape map, suggesting that bi-and multidentate ligands with varying topologies have a strong influence in determining the molecular geometries.…”

Selective oxo ligand functionalisation and substitution reactivity in an oxo/catecholate-bridged UIV/UIV Pacman complex

“…To the best of our knowledge, reactions involving A and elemental sulfur and selenium to provide complexes 3 and 4 are the rst examples of any d-or f-block bimetallic m-oxo complex possessing the ability to activate elemental chalcogens, which in both cases typically requires access to low valent, highly reducing metal precursors such as U III , 7,[29][30][31][32]34 Yb II , 45,46 47 and 48) and Ni I . 49 This reactivity sheds light on how uranium reactivity differs from the d-block and remainder of the f-block elements, and how complexes containing groups considered inert by convention can be manipulated for productive transformations.…”

“…To the best of our knowledge, reactions involving A and elemental sulfur and selenium to provide complexes 3 and 4 are the first examples of any d- or f-block bimetallic μ-oxo complex possessing the ability to activate elemental chalcogens, which in both cases typically requires access to low valent, highly reducing metal precursors such as U III , 7 , 29 – 32 , 34 Yb II , 45 , 46 V I /V III ( ref. 47 and 48 ) and Ni I .…”

“…1B). 7 A variety of U IV -O-U IV containing complexes with many different supporting ligands have also been formed, since this is normally a thermodynamic redox processes. [8][9][10][11] The functionalisation of a bridging oxo ligand between two U IV centres is still very rare as the U-O bond is very strong; the single U-O bond in ½Cp 0 2 U IV O (Cp' ¼ C 5 H 2 -1,2,4-t Bu 3 ) is 293 kJ mol À1 stronger than the double U]NMe bond in ½Cp 0 2 U IV NMe.…”

“…1B ). 7 A variety of U IV –O–U IV containing complexes with many different supporting ligands have also been formed, since this is normally a thermodynamic sink. Such complexes are commonly formed either by treating 2 equiv.…”