Photochemical Route to Actinide-Transition Metal Bonds: Synthesis, Characterization and Reactivity of a Series of Thorium and Uranium Heterobimetallic Complexes

Abstract

Photochemical route to actinide-transition metal bonds: synthesis,characterization and reactivity of a series of thoriumand uranium heterobimetallic complexes Permalink https://escholarship.org/uc/item/5qz819w8

Carbon–Nitrogen Bond Cleavage by a Thorium‐NHC‐bpy Complex

“…Thet erminal C61 À C62 bond length, at 1.35 (2) ,f alls in the range expected for aC -(sp 2 )ÀC(sp 2 )b ond and supports the assignment of ab ut-3enyl substituent. As seen for 2,t he bpy ligand is asymmetrically bound to the metal center, with aT h1 À N10 bond length of 2.62 (5) and aT h1 À N9 bond length of 2.38 (6) . Remaining metrical parameters of 6 are similar to those found in 2 (Figure 1), 3,a nd 4 ( Figures S25 and S26, respectively).…”

“…[1][2][3] Ther ich reaction chemistry of thorium has been most developed in metallocene-supported systems,o utside of which relatively few alternative supporting ligand frameworks have been explored. Our interest in utilizing new ligand platforms [4][5][6] recently led to the discovery of auseful bis(NHC)borate motif that stabilizes reactive thorium compounds. [7] Upon also incorporating ar edox-active bipyridine ligand into the coordination sphere,t he NHC-thorium-bpy complex (1)w as found to engage in ar ange of chemical transformations and support an unusual open-shell singlet electronic structure (f 1 p* 1 ).…”

Early/Late Heterobimetallic Tantalum/Rhodium Species Assembled Through a Novel Bifunctional NHC‐OH Ligand

“…One identified strategy for directinga nd stabilising early/late heterobimetallic assemblies is to take profit of bifunctional bridging ligands featuring two distinct coordination motifs: one hard, able to form strongb onds with oxophilic early TMs, and one soft, featuring as trong affinity for late TMs. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] In most examples reported to date in the literature, the latemetald onor is ap hosphine-derivedm oiety.Encouraged by the flagshipr ole played by N-heterocyclic carbene (NHC) organometallicc omplexes in homogeneous catalysis, especially with late TMs, [21][22][23][24][25][26] we have identified alkoxy-functionalised NHC ligands [27][28][29][30] as promising alternatives.Q uite surprisingly,t ot he best of our knowledge,t hese ligandsh ave not been specifically used to stabilisee arly/late heterobimetallic assemblies so far. In as ingle precedent, Arnold and co-workersr eported that UL 4 (L = OCMe 2 CH 2 [1-C(NCHCHNiPr)]) reacts with molybdenuma nd tungsten carbonyls to yield new entities formulated as [UL 4 Mo(CO) 4 ]a nd [UL 4 W(CO) 5 ], respectively.Y et it is unclear how the metals are arranged in these compounds.…”

Uranium rhodium bonding in heterometallic complexes

“…Complexes with bonds between uranium and transition metals are rare and limited to iron, 4–6 ruthenium, 4,7 cobalt, 8–10 rhenium, 11–13 group 10 metals, 14 and silver. 15 The first examples, Cp 3 U-MCp(CO) 2 (M = Fe, Ru), were reported by Sternal and Marks in 1987.…”

“…This was based on their earlier work on thorium, which allowed the crystallographic verification of a thorium–ruthenium bond in Cp 3 Th-RuCp(CO) 2 . 16 More recent examples of thorium-transition metal complexes include combinations with cobalt 10 and copper. 17 …”