Structure and properties of [(4,6-tBu2C6H2O)2Se]2An(THF)2, An = U, Np, and their reaction with p-benzoquinone.

The synthesis and characterization of U(iv) and Np(iv) selenium bis(phenolate) complexes are reported. The reaction of two equivalents of the U(iv) complex with p-benzoquinone results in the formation of a U(v)-U(v) species with a bridging reduced quinone. This represents a rare example of high-valent uranium chemistry as well as a rare example of a neptunium aryloxide complex

Dithio- and Diselenophosphinate Thorium(IV) and Uranium(IV) Complexes: Molecular and Electronic Structures, Spectroscopy, and Transmetalation Reactivity

We report a comparison of the molecular and electronic structures of dithio- and diselenophosphinate, (E₂PR₂)^1– (E = S, Se; R = ^<i>i</i>Pr, ^<i>t</i>Bu), with thorium­(IV) and uranium­(IV) complexes. For the thorium dithiophosphinate complexes, reaction of ThCl₄(DME)₂ with 4 equiv of KS₂PR₂ (R = ^<i>i</i>Pr, ^<i>t</i>Bu) produced the homoleptic complexes, Th­(S₂P^<i>i</i>Pr₂)₄ (<b>1S-Th-</b>^{<i><b>i</b></i>}<b>Pr</b>) and Th­(S₂P^<i>t</i>Bu₂)₄ (<b>2S-Th-</b>^{<i><b>t</b></i>}<b>Bu</b>). The diselenophosphinate complexes were synthesized in a similar manner using KSe₂PR₂ to produce Th­(Se₂P^<i>i</i>Pr₂)₄ (<b>1Se-Th-</b>^{<i><b>i</b></i>}<b>Pr</b>) and Th­(Se₂P^<i>t</i>Bu₂)₄ (<b>2Se-Th-</b>^{<i><b>t</b></i>}<b>Bu</b>). U­(S₂P^<i>i</i>Pr₂)₄, <b>1S-U-</b>^{<i><b>i</b></i>}<b>Pr</b>, could be made directly from UCl₄ and 4 equiv of KS₂P^<i>i</i>Pr₂. With (Se₂P^<i>i</i>Pr₂)^1–, using UCl₄ and 3 or 4 equiv of KSe₂P^<i>i</i>Pr₂ yielded the monochloride product U­(Se₂P^<i>i</i>Pr₂)₃Cl (<b>3Se-U</b>^{<i><b>i</b></i><b>Pr</b>}<b>-Cl</b>), but using UI₄(1,4-dioxane)₂ produced the homoleptic U­(Se₂P^<i>i</i>Pr₂)₄ (<b>1Se-U-</b>^{<i><b>i</b></i>}<b>Pr</b>). Similarly, the reaction of UCl₄ with 4 equiv of KS₂P^<i>t</i>Bu₂ yielded U­(S₂P^<i>t</i>Bu₂)₄ (<b>2S-U-</b>^{<i><b>t</b></i>}<b>Bu</b>), whereas the reaction with KSe₂P^<i>t</i>Bu₂ resulted in the formation of U­(Se₂P^<i>t</i>Bu₂)₃Cl (<b>4Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Cl</b>). Using UI₄(1,4-dioxane)₂ and 4 equiv of KSe₂P^<i>t</i>Bu₂ with UCl₄ in acetonitrile yielded U­(Se₂P^<i>t</i>Bu₂)₄ (<b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b>). Transmetalation reactions were investigated with complex <b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b> and various CuX (X = Br, I) salts to yield U­(Se₂P^<i>t</i>Bu₂)₃X (<b>6Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Br</b> and <b>7Se-U</b>^{<b><i>t</i>Bu</b>}<b>-I</b>) and 0.25 equiv of [Cu­(Se₂P^<i>t</i>Bu₂)]₄ (<b>8Se-Cu-</b>^{<i><b>t</b></i>}<b>Bu</b>). Additionally, <b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b> underwent transmetalation reactions with Hg₂F₂ and ZnCl₂ to yield U­(Se₂P^<i>t</i>Bu₂)₃F (<b>6</b>) and U­(Se₂P^<i>t</i>Bu₂)₃Cl (<b>4Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Cl</b>), respectively. The molecular structures were analyzed using ¹H, ¹³C, ³¹P, and ⁷⁷Se NMR and IR spectroscopy and structurally characterized using X-ray crystallography. Using the QTAIM approach, the electronic structure of all homoleptic complexes was probed, showing slightly more covalent bonding character in actinide–selenium bonds over actinide–sulfur bonds

Dithio- and Diselenophosphinate Thorium(IV) and Uranium(IV) Complexes: Molecular and Electronic Structures, Spectroscopy, and Transmetalation Reactivity

We report a comparison of the molecular and electronic structures of dithio- and diselenophosphinate, (E₂PR₂)^1– (E = S, Se; R = ^<i>i</i>Pr, ^<i>t</i>Bu), with thorium­(IV) and uranium­(IV) complexes. For the thorium dithiophosphinate complexes, reaction of ThCl₄(DME)₂ with 4 equiv of KS₂PR₂ (R = ^<i>i</i>Pr, ^<i>t</i>Bu) produced the homoleptic complexes, Th­(S₂P^<i>i</i>Pr₂)₄ (<b>1S-Th-</b>^{<i><b>i</b></i>}<b>Pr</b>) and Th­(S₂P^<i>t</i>Bu₂)₄ (<b>2S-Th-</b>^{<i><b>t</b></i>}<b>Bu</b>). The diselenophosphinate complexes were synthesized in a similar manner using KSe₂PR₂ to produce Th­(Se₂P^<i>i</i>Pr₂)₄ (<b>1Se-Th-</b>^{<i><b>i</b></i>}<b>Pr</b>) and Th­(Se₂P^<i>t</i>Bu₂)₄ (<b>2Se-Th-</b>^{<i><b>t</b></i>}<b>Bu</b>). U­(S₂P^<i>i</i>Pr₂)₄, <b>1S-U-</b>^{<i><b>i</b></i>}<b>Pr</b>, could be made directly from UCl₄ and 4 equiv of KS₂P^<i>i</i>Pr₂. With (Se₂P^<i>i</i>Pr₂)^1–, using UCl₄ and 3 or 4 equiv of KSe₂P^<i>i</i>Pr₂ yielded the monochloride product U­(Se₂P^<i>i</i>Pr₂)₃Cl (<b>3Se-U</b>^{<i><b>i</b></i><b>Pr</b>}<b>-Cl</b>), but using UI₄(1,4-dioxane)₂ produced the homoleptic U­(Se₂P^<i>i</i>Pr₂)₄ (<b>1Se-U-</b>^{<i><b>i</b></i>}<b>Pr</b>). Similarly, the reaction of UCl₄ with 4 equiv of KS₂P^<i>t</i>Bu₂ yielded U­(S₂P^<i>t</i>Bu₂)₄ (<b>2S-U-</b>^{<i><b>t</b></i>}<b>Bu</b>), whereas the reaction with KSe₂P^<i>t</i>Bu₂ resulted in the formation of U­(Se₂P^<i>t</i>Bu₂)₃Cl (<b>4Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Cl</b>). Using UI₄(1,4-dioxane)₂ and 4 equiv of KSe₂P^<i>t</i>Bu₂ with UCl₄ in acetonitrile yielded U­(Se₂P^<i>t</i>Bu₂)₄ (<b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b>). Transmetalation reactions were investigated with complex <b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b> and various CuX (X = Br, I) salts to yield U­(Se₂P^<i>t</i>Bu₂)₃X (<b>6Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Br</b> and <b>7Se-U</b>^{<b><i>t</i>Bu</b>}<b>-I</b>) and 0.25 equiv of [Cu­(Se₂P^<i>t</i>Bu₂)]₄ (<b>8Se-Cu-</b>^{<i><b>t</b></i>}<b>Bu</b>). Additionally, <b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b> underwent transmetalation reactions with Hg₂F₂ and ZnCl₂ to yield U­(Se₂P^<i>t</i>Bu₂)₃F (<b>6</b>) and U­(Se₂P^<i>t</i>Bu₂)₃Cl (<b>4Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Cl</b>), respectively. The molecular structures were analyzed using ¹H, ¹³C, ³¹P, and ⁷⁷Se NMR and IR spectroscopy and structurally characterized using X-ray crystallography. Using the QTAIM approach, the electronic structure of all homoleptic complexes was probed, showing slightly more covalent bonding character in actinide–selenium bonds over actinide–sulfur bonds

Insertion Reactions and Catalytic Hydrophosphination of Heterocumulenes using α‑Metalated <i>N</i>,<i>N</i>‑Dimethylbenzylamine Rare-Earth-Metal Complexes

The reactivity of homoleptic α-metalated dimethylbenzylamine lanthanide complexes (α<i>-</i>Ln­(DMBA)₃; Ln = La, Y; DMBA = α-deprotonated dimethylbenzylamine) was probed through a series of stoichiometric insertion and catalytic hydrophosphination reactions. Both rare-earth-metal species inserted 3 equiv of various carbodiimides to form the corresponding homoleptic amidinates. α<i>-</i>La­(DMBA)₃ was also found to be a useful precatalyst for the room-temperature hydrophosphination of heterocumulenes to form phosphaguanidines, phosphaureas, and phosphathioureas in moderate to excellent isolated yields. Furthermore, through a series of stepwise stoichiometric protonation and insertion reactions, a plausible mechanism for the hydrophosphination catalysis was investigated

Dithio- and Diselenophosphinate Thorium(IV) and Uranium(IV) Complexes: Molecular and Electronic Structures, Spectroscopy, and Transmetalation Reactivity

We report a comparison of the molecular and electronic structures of dithio- and diselenophosphinate, (E₂PR₂)^1– (E = S, Se; R = ^<i>i</i>Pr, ^<i>t</i>Bu), with thorium­(IV) and uranium­(IV) complexes. For the thorium dithiophosphinate complexes, reaction of ThCl₄(DME)₂ with 4 equiv of KS₂PR₂ (R = ^<i>i</i>Pr, ^<i>t</i>Bu) produced the homoleptic complexes, Th­(S₂P^<i>i</i>Pr₂)₄ (<b>1S-Th-</b>^{<i><b>i</b></i>}<b>Pr</b>) and Th­(S₂P^<i>t</i>Bu₂)₄ (<b>2S-Th-</b>^{<i><b>t</b></i>}<b>Bu</b>). The diselenophosphinate complexes were synthesized in a similar manner using KSe₂PR₂ to produce Th­(Se₂P^<i>i</i>Pr₂)₄ (<b>1Se-Th-</b>^{<i><b>i</b></i>}<b>Pr</b>) and Th­(Se₂P^<i>t</i>Bu₂)₄ (<b>2Se-Th-</b>^{<i><b>t</b></i>}<b>Bu</b>). U­(S₂P^<i>i</i>Pr₂)₄, <b>1S-U-</b>^{<i><b>i</b></i>}<b>Pr</b>, could be made directly from UCl₄ and 4 equiv of KS₂P^<i>i</i>Pr₂. With (Se₂P^<i>i</i>Pr₂)^1–, using UCl₄ and 3 or 4 equiv of KSe₂P^<i>i</i>Pr₂ yielded the monochloride product U­(Se₂P^<i>i</i>Pr₂)₃Cl (<b>3Se-U</b>^{<i><b>i</b></i><b>Pr</b>}<b>-Cl</b>), but using UI₄(1,4-dioxane)₂ produced the homoleptic U­(Se₂P^<i>i</i>Pr₂)₄ (<b>1Se-U-</b>^{<i><b>i</b></i>}<b>Pr</b>). Similarly, the reaction of UCl₄ with 4 equiv of KS₂P^<i>t</i>Bu₂ yielded U­(S₂P^<i>t</i>Bu₂)₄ (<b>2S-U-</b>^{<i><b>t</b></i>}<b>Bu</b>), whereas the reaction with KSe₂P^<i>t</i>Bu₂ resulted in the formation of U­(Se₂P^<i>t</i>Bu₂)₃Cl (<b>4Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Cl</b>). Using UI₄(1,4-dioxane)₂ and 4 equiv of KSe₂P^<i>t</i>Bu₂ with UCl₄ in acetonitrile yielded U­(Se₂P^<i>t</i>Bu₂)₄ (<b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b>). Transmetalation reactions were investigated with complex <b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b> and various CuX (X = Br, I) salts to yield U­(Se₂P^<i>t</i>Bu₂)₃X (<b>6Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Br</b> and <b>7Se-U</b>^{<b><i>t</i>Bu</b>}<b>-I</b>) and 0.25 equiv of [Cu­(Se₂P^<i>t</i>Bu₂)]₄ (<b>8Se-Cu-</b>^{<i><b>t</b></i>}<b>Bu</b>). Additionally, <b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b> underwent transmetalation reactions with Hg₂F₂ and ZnCl₂ to yield U­(Se₂P^<i>t</i>Bu₂)₃F (<b>6</b>) and U­(Se₂P^<i>t</i>Bu₂)₃Cl (<b>4Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Cl</b>), respectively. The molecular structures were analyzed using ¹H, ¹³C, ³¹P, and ⁷⁷Se NMR and IR spectroscopy and structurally characterized using X-ray crystallography. Using the QTAIM approach, the electronic structure of all homoleptic complexes was probed, showing slightly more covalent bonding character in actinide–selenium bonds over actinide–sulfur bonds

Dithio- and Diselenophosphinate Thorium(IV) and Uranium(IV) Complexes: Molecular and Electronic Structures, Spectroscopy, and Transmetalation Reactivity

We report a comparison of the molecular and electronic structures of dithio- and diselenophosphinate, (E₂PR₂)^1– (E = S, Se; R = ^<i>i</i>Pr, ^<i>t</i>Bu), with thorium­(IV) and uranium­(IV) complexes. For the thorium dithiophosphinate complexes, reaction of ThCl₄(DME)₂ with 4 equiv of KS₂PR₂ (R = ^<i>i</i>Pr, ^<i>t</i>Bu) produced the homoleptic complexes, Th­(S₂P^<i>i</i>Pr₂)₄ (<b>1S-Th-</b>^{<i><b>i</b></i>}<b>Pr</b>) and Th­(S₂P^<i>t</i>Bu₂)₄ (<b>2S-Th-</b>^{<i><b>t</b></i>}<b>Bu</b>). The diselenophosphinate complexes were synthesized in a similar manner using KSe₂PR₂ to produce Th­(Se₂P^<i>i</i>Pr₂)₄ (<b>1Se-Th-</b>^{<i><b>i</b></i>}<b>Pr</b>) and Th­(Se₂P^<i>t</i>Bu₂)₄ (<b>2Se-Th-</b>^{<i><b>t</b></i>}<b>Bu</b>). U­(S₂P^<i>i</i>Pr₂)₄, <b>1S-U-</b>^{<i><b>i</b></i>}<b>Pr</b>, could be made directly from UCl₄ and 4 equiv of KS₂P^<i>i</i>Pr₂. With (Se₂P^<i>i</i>Pr₂)^1–, using UCl₄ and 3 or 4 equiv of KSe₂P^<i>i</i>Pr₂ yielded the monochloride product U­(Se₂P^<i>i</i>Pr₂)₃Cl (<b>3Se-U</b>^{<i><b>i</b></i><b>Pr</b>}<b>-Cl</b>), but using UI₄(1,4-dioxane)₂ produced the homoleptic U­(Se₂P^<i>i</i>Pr₂)₄ (<b>1Se-U-</b>^{<i><b>i</b></i>}<b>Pr</b>). Similarly, the reaction of UCl₄ with 4 equiv of KS₂P^<i>t</i>Bu₂ yielded U­(S₂P^<i>t</i>Bu₂)₄ (<b>2S-U-</b>^{<i><b>t</b></i>}<b>Bu</b>), whereas the reaction with KSe₂P^<i>t</i>Bu₂ resulted in the formation of U­(Se₂P^<i>t</i>Bu₂)₃Cl (<b>4Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Cl</b>). Using UI₄(1,4-dioxane)₂ and 4 equiv of KSe₂P^<i>t</i>Bu₂ with UCl₄ in acetonitrile yielded U­(Se₂P^<i>t</i>Bu₂)₄ (<b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b>). Transmetalation reactions were investigated with complex <b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b> and various CuX (X = Br, I) salts to yield U­(Se₂P^<i>t</i>Bu₂)₃X (<b>6Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Br</b> and <b>7Se-U</b>^{<b><i>t</i>Bu</b>}<b>-I</b>) and 0.25 equiv of [Cu­(Se₂P^<i>t</i>Bu₂)]₄ (<b>8Se-Cu-</b>^{<i><b>t</b></i>}<b>Bu</b>). Additionally, <b>2Se-U-</b>^{<i><b>t</b></i>}<b>Bu</b> underwent transmetalation reactions with Hg₂F₂ and ZnCl₂ to yield U­(Se₂P^<i>t</i>Bu₂)₃F (<b>6</b>) and U­(Se₂P^<i>t</i>Bu₂)₃Cl (<b>4Se-U</b>^{<b><i>t</i>Bu</b>}<b>-Cl</b>), respectively. The molecular structures were analyzed using ¹H, ¹³C, ³¹P, and ⁷⁷Se NMR and IR spectroscopy and structurally characterized using X-ray crystallography. Using the QTAIM approach, the electronic structure of all homoleptic complexes was probed, showing slightly more covalent bonding character in actinide–selenium bonds over actinide–sulfur bonds

Insertion Reactions and Catalytic Hydrophosphination of Heterocumulenes using α‑Metalated <i>N</i>,<i>N</i>‑Dimethylbenzylamine Rare-Earth-Metal Complexes

The reactivity of homoleptic α-metalated dimethylbenzylamine lanthanide complexes (α<i>-</i>Ln­(DMBA)₃; Ln = La, Y; DMBA = α-deprotonated dimethylbenzylamine) was probed through a series of stoichiometric insertion and catalytic hydrophosphination reactions. Both rare-earth-metal species inserted 3 equiv of various carbodiimides to form the corresponding homoleptic amidinates. α<i>-</i>La­(DMBA)₃ was also found to be a useful precatalyst for the room-temperature hydrophosphination of heterocumulenes to form phosphaguanidines, phosphaureas, and phosphathioureas in moderate to excellent isolated yields. Furthermore, through a series of stepwise stoichiometric protonation and insertion reactions, a plausible mechanism for the hydrophosphination catalysis was investigated

Formation of a Bridging Phosphinidene Thorium Complex

The synthesis and structural determination of the first thorium phosphinidene complex are reported. The reaction of 2 equiv of (C₅Me₅)₂Th­(CH₃)₂ with H₂P­(2,4,6-^<i>i</i>Pr₃C₆H₂) at 95 °C produces [(C₅Me₅)₂Th]₂(μ₂-P­[(2,6-<i>C</i>H₂CHCH₃)₂-4-^<i>i</i>PrC₆H₂] as well as 4 equiv of methane, 2 equiv from deprotonation of the phosphine and 2 equiv from C–H bond activation of one methyl group of each of the isopropyl groups at the 2- and 6-positions. Transition state calculations indicate that the steps in the mechanism are P–H, C–H, C–H, and then P–H bond activation to form the phosphinidene