Complexes Featuring a cis‐[MUM] Core (M=Rh, Ir): A New Route to Uranium‐Metal Multiple Bonds

Abstract

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 →0false→ ${{\rm{ \mathbin{{\stackrel{\textstyle\rightarrow} { {\smash{\rightarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ U ←0false← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M] core (M=Rh, Ir), which exhibits an unprecedented arrangement of two M →0false→ ${{\rm{ \mathbin{{\stackrel{\textstyle\rightarrow} { {\smash{\rightarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ 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 ←0false← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M double dative bonds in these complexes. This study not only enriches the U ←0false← ${{\rm{ \mathbin{{\stackrel{\textstyle\leftarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }}}$ M multiple bond chemistry, but also provides a new opportunity to explore the bonding of actinide elements.

Synthesis and reactivity of a uranium(iv) complex supported by a monoanionic nitrogen–phosphorus ligand

“…50 The U–Rh bond length in 6 is longer than the U–Rh single-bond lengths reported in [U IV I 2 (μ-OAr P -1κ 1 O ,2κ 1 P ) 2 Rh I (μ-I)] 2 (Ar P O − = 2-(diphenylphosphino)-6- tert -butyl-4-methylphenoxide) (2.7601(5) Å), U IV I(μ-I)(μ-OAr P -1κ 1 O ,2κ 1 P ) 3 Rh I (2.7630(5) Å) 95 and U[N(CH 3 )(CH 2 CH 2 NP i Pr 2 ) 2 ](μ-Me) 2 Rh 2 (μ-Me) 4 Mg(C 4 H 8 O) (2.6612(5) Å). 34 The U–Ir bond length (2.8656(3) Å) is shorter than the sum of the covalent single-bond radii of U and Ir (2.92 Å), but longer than the U–Ir single-bond length in complex U[N(CH 3 )(CH 2 CH 2 NP i Pr 2 ) 2 ] [(μ-Me) 2 Ir 2 (μ-Me) 4 Mg(C 4 H 8 O)] (2.6968(4) Å). 34 Nevertheless, the U–Rh/Ir bond lengths observed in 6 and 7 are consistent with the presence of a U–M bonding interaction in these clusters.…”

“…34 The U–Ir bond length (2.8656(3) Å) is shorter than the sum of the covalent single-bond radii of U and Ir (2.92 Å), but longer than the U–Ir single-bond length in complex U[N(CH 3 )(CH 2 CH 2 NP i Pr 2 ) 2 ] [(μ-Me) 2 Ir 2 (μ-Me) 4 Mg(C 4 H 8 O)] (2.6968(4) Å). 34 Nevertheless, the U–Rh/Ir bond lengths observed in 6 and 7 are consistent with the presence of a U–M bonding interaction in these clusters.…”

“…1) is an effective platform for the construction of heterometallic clusters with multiple U–M single or double bonds and could be used to synthesize neutral uranium( ii ) species. 32–34 In 2022, Layfield and co-workers reported the first example of a uranium( i ) complex supported by a monoanionic ligand, η 5 -C 5 i Pr 5 . 35 Very recently, Mazzanti and co-workers found that the –OSiPh 3 ligand could be used to stabilize uranium( i ) synthons.…”

Heterometallic Clusters with Cerium–Transition-Metal Bonding Supported by Nitrogen–Phosphorus Ligands

“…Despite this considerable progress, the chemistry of RE–M bonds is still in its infancy compared with that of transition metals. , With our ongoing interest in the double-layer N-P ligands and metal–metal bonds, we report here the successful isolation and characterization of a series of complexes, 2 , 3 , 5 , 6 , and 7 , which all feature Ce–M (M = Ni, Pd, and Pt) bonds supported by N–P ligand VI or N–CH 2 –P ligand VII (Figure ). Complexes 2 and 3 contain up to four Ce–Pd/Pt bonds, which is the largest number of RE–M bonds ever observed in a molecule.…”

Magnesium complexes supported by a dianionic double layer nitrogen–phosphorus ligand: a synthesis and reactivity study

“…In recent years, we found that the double layer N–P ligands are not only effective platforms for the construction of heterometallic clusters with metal–metal bonds 25–31 but also play an important role in the activation of small molecules and catalysis. 32–34 Based on our continuing interest in the construction of heterometallic clusters with metal–metal bonds supported by double layer N–P ligands, we have attempted to synthesize complexes with metal–metal bonds between Mg and coinage metals.…”