Crystalline Diuranium Phosphinidiide and μ‐Phosphido Complexes with Symmetric and Asymmetric UPU Cores

Abstract

. Compounds 4 and 7 are unprecedented examples of uranium phosphido complexes outside of matrix isolation studies,and they rapidly decompose in solution underscoring the paucity of uranium phosphido complexes.I nterestingly, 4 and 7 feature symmetric and asymmetric UPU cores,r espectively,r eflecting their differing steric profiles.

Isolation of uranium(iii) primary phosphido complexes

“…In comparison, Cp* 2 U(PH-2,4,6- i Pr 3 C 6 H 2 )(OPMe 3 ) (U–P: 3.031(1)) 6 is slightly longer than 2-PPh , 2-PMes , and 2-PMes* , likely due to the effect of the bound OPMe 3 . Tetravalent Cp* 2 U[P(H)Mes] 2 (U–P: 2.7768(12) Å) 3 and [{U(Tren TIPS )} 2 (μ-PH)] (U–P: 2.8187(12) and 2.8110(12) Å), 4 are ∼0.25 Å shorter, consistent with the smaller uranium( iv ) ion relative to uranium( iii ).…”

“…Several groups have made strides with the isolation of compounds featuring U-P single bonds. [3][4][5][6] Bonds derived from primary phosphines are scarce, likely due to the lack of steric protection. Examples of uranium(IV) primary phosphido compounds include Cp* 2 U[PHMes] 2 (Cp* = 1,2,3,4,5-pentamethylcyclopentadienide), recently reported by Walensky 3 and [Z 5 -1,3-(Me 3 C) 2 C 5 H 3 ] 2 U(PH-2,4,6-i Pr 3 C 6 H 2 )(OPMe 3 ) from Zi and Walter.…”

“…Examples of uranium( iv ) primary phosphido compounds include Cp* 2 U[PHMes] 2 (Cp* = 1,2,3,4,5-pentamethylcyclopentadienide), recently reported by Walensky 3 and [η 5 -1,3-(Me 3 C) 2 C 5 H 3 ] 2 U(PH-2,4,6- i Pr 3 C 6 H 2 )(OPMe 3 ) from Zi and Walter. 7 Liddle has reported a uranium( iv ) bridging phosphido complex, [{U(Tren TIPS )} 2 (μ-PH)] (Tren TIPS = N(CH 2 CH 2 NSi i Pr 3 ) 3 and the terminal complex, [{U(Tren TIPS )(PH 2 )], 4,8 whereas Marks has generated a dimeric uranium( iv ) phosphido, [Cp* 2 U(OCH 3 )] 2 PH. 5 Uranium( iii ) primary phosphido examples, such as Cp* 2 U(PH-2,4,6-R 3 C 6 H 2 )(OPMe 3 ) (R = i Pr, t Bu), have also been reported by Zi and Walter.…”

A μ‐Phosphido Diiron Dumbbell in Multiple Oxidation States

“…The Mössbauer spectrum of 3 shows a quadruple doublet with parameters δ =0.01 mm s −1 and Δ E Q =1.94 mm s −1 , quite similar to those of [(LFe) 2 (μ‐O)](OTf) 4 ( δ =0.04 mm s −1 and Δ E Q =2.56 mm s −1 ) and indicative of ferric complexes of the tetracarbene macrocycle L . Although μ‐oxido diiron(III) complexes are abundant and a number of μ‐phosphido complexes have been reported, mainly for 4d and 5d metals, the Fe‐(μ‐P)‐Fe core with a “naked” bridging phosphido ligand is unprecedented.…”

Actinide Triamidoamine (TrenR) Chemistry: Uranium and Thorium Derivatives Supported by a Diphenyl‐tert‐Butyl‐Silyl‐Tren Ligand

“…[1][2][3] This is due to a combination of: (i) three amide centres that are covalent σ-and dative π-donors; (ii) the presence of a tertiary amine that can modulate the strength of its dative σ-donation to a coordinated An-ion as required by the metal and also engage in inverse-trans-influence (ITI) binding; (iii) being a quadridentate ligand that maximises kinetic and thermodynamic stability of the resulting An-complexes; (iv) varied N-silyl substitution patterns that can systematically tune the steric and electronic properties of the Tren R scaffold, including producing a well-defined pocket at the coordinated An-metal with which to stabilise novel linkages or reactivity. It is therefore the case that Tren R -ligands have supported novel Anligand multiple bonds, [4][5][6][7][8][9][10][11][12][13][14][15] An-metal bonds, [16][17][18][19][20][21] novel main group moieties, [22][23][24][25][26][27][28][29][30][31] uranyl activation, [32,33] small molecule activation, [34][35][36][37][38][39][40][41][42]…”