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Isolation of Elusive HAsAsH in a Crystalline Diuranium(IV) Complex.

ABSTRACT: The HAsAsH molecule has hitherto only been proposed tentatively as a short-lived species generated in electrochemical or microwave-plasma experiments. After two centuries of inconclusive or disproven claims of HAsAsH formation in the condensed phase, we report the isolation and structural authentication of HAsAsH in the diuranium(IV) complex [{U(Tren^TIPS)}₂(?-?²:?²-As₂H₂)] (3, Tren^TIPS=N(CH₂CH₂NSiPrⁱ₃)₃; Prⁱ=CH(CH₃)₂). Complex 3 was prepared by deprotonation and oxidative homocoupling of an arsenide precursor. Characterization and computational data are consistent with back-bonding-type interactions from uranium to the HAsAsH ?*-orbital. This experimentally confirms the theoretically predicted excellent ?-acceptor character of HAsAsH, and is tantamount to full reduction to the diarsane-1,2-diide form.

SUBMITTER: Gardner BM

PROVIDER: S-EPMC4955221 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Isolation of Elusive HAsAsH in a Crystalline Diuranium(IV) Complex.

Gardner Benedict M BM Balázs Gábor G Scheer Manfred M Wooles Ashley J AJ Tuna Floriana F McInnes Eric J L EJ McMaster Jonathan J Lewis William W Blake Alexander J AJ Liddle Stephen T ST

Angewandte Chemie (Weinheim an der Bergstrasse, Germany) 20151028 50

The HAsAsH molecule has hitherto only been proposed tentatively as a short-lived species generated in electrochemical or microwave-plasma experiments. After two centuries of inconclusive or disproven claims of HAsAsH formation in the condensed phase, we report the isolation and structural authentication of HAsAsH in the diuranium(IV) complex [{U(TrenTIPS)}2(μ-η2:η2-As2H2)] (3, TrenTIPS=N(CH2CH2</s ...[more]

PMID: 27478272

Similar Datasets

Isolation of Elusive HAsAsH in a Crystalline Diuranium(IV) Complex.

Project description:The HAsAsH molecule has hitherto only been proposed tentatively as a short-lived species generated in electrochemical or microwave-plasma experiments. After two centuries of inconclusive or disproven claims of HAsAsH formation in the condensed phase, we report the isolation and structural authentication of HAsAsH in the diuranium(IV) complex [{U(Tren(TIPS) )}2 (?-?(2) :?(2) -As2 H2 )] (3, Tren(TIPS) =N(CH2 CH2 NSiPr(i) 3 )3 ; Pr(i) =CH(CH3 )2 ). Complex 3 was prepared by deprotonation and oxidative homocoupling of an arsenide precursor. Characterization and computational data are consistent with back-bonding-type interactions from uranium to the HAsAsH ?*-orbital. This experimentally confirms the theoretically predicted excellent ?-acceptor character of HAsAsH, and is tantamount to full reduction to the diarsane-1,2-diide form.

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An isolable, crystalline complex of square-planar silicon(IV).

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Crystalline Diuranium Phosphinidiide and ?-Phosphido Complexes with Symmetric and Asymmetric UPU Cores.

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Isolation of the Elusive Heptavanadate Anion with Trisalkoxide Ligands.

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Caesium diuranium hexa-telluride.

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Facile N-functionalization and strong magnetic communication in a diuranium(v) bis-nitride complex.

Project description:Uranium nitride complexes are of high interest because of their ability to effect dinitrogen reduction and functionalization and to promote magnetic communication, but studies of their properties and reactivity remain rare. Here we have prepared in 73% yield the diuranium(v) bis-nitride complex [K2{[U(OSi(O t Bu)3)3]2(μ-N)2}], 4, from the thermal decomposition of the nitride-, azide-bridged diuranium(iv) complex [K2{[U(OSi(O t Bu)3)3]2(μ-N)(μ-N3)}], 3. The bis-nitride 4 reacts in ambient conditions with 1 equiv. of CS2 and 1 equiv. of CO2 resulting in N-C bond formation to afford the diuranium(v) complexes [K2{[U(OSi(O t Bu)3)3]2(μ-N)(μ-S)(μ-NCS)}], 5 and [K2{[U(OSi(O t Bu)3)3]2(μ-N)(μ-O)(μ-NCO)}], 6, respectively. Both nitrides in 4 react with CO resulting in oxidative addition of CO to one nitride and CO cleavage by the second nitride to afford the diuranium(iv) complex [K2{[U(OSi(O t Bu)3)3]2(μ-CN)(μ-O)(μ-NCO)}], 7. Complex 4 also effects the remarkable oxidative cleavage of H2 in mild conditions to afford the bis-imido bridged diuranium(iv) complex [K2{[U(OSi(O t Bu)3)3]2(μ-NH)2}], 8 that can be further protonated to afford ammonia in 73% yield. Complex 8 provides a good model for hydrogen cleavage by metal nitrides in the Haber-Bosch process. The measured magnetic data show an unusually strong antiferromagnetic coupling between uranium(v) ions in the complexes 4 and 6 with Neel temperatures of 77 K and 60 K respectively, demonstrating that nitrides are attractives linkers for promoting magnetic communication in uranium complexes.

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An Inverted-Sandwich Diuranium μ-η(5):η(5)-Cyclo-P5 Complex Supported by U-P5 δ-Bonding.

Project description:Reaction of [U(Tren(TIPS))] [1, Tren(TIPS)=N(CH2CH2NSiiPr3)3] with 0.25 equivalents of P4 reproducibly affords the unprecedented actinide inverted sandwich cyclo-P5 complex [{U(Tren(TIPS))}2(μ-η(5):η(5)-cyclo-P5)] (2). All prior examples of cyclo-P5 are stabilized by d-block metals, so 2 shows that cyclo-P5 does not require d-block ions to be prepared. Although cyclo-P5 is isolobal to cyclopentadienyl, which usually bonds to metals via σ- and π-interactions with minimal δ-bonding, theoretical calculations suggest the principal bonding in the U(P5)U unit is polarized δ-bonding. Surprisingly, the characterization data are overall consistent with charge transfer from uranium to the cyclo-P5 unit to give a cyclo-P5 charge state that approximates to a dianionic formulation. This is ascribed to the larger size and superior acceptor character of cyclo-P5 compared to cyclopentadienyl, the strongly reducing nature of uranium(III), and the availability of uranium δ-symmetry 5f orbitals.

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An Inverted-Sandwich Diuranium ?-?(5):?(5)-Cyclo-P5 Complex Supported by U-P5 ?-Bonding.

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Atomic structures of respiratory complex III2, complex IV, and supercomplex III2-IV from vascular plants.

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| S-EPMC7815315 | biostudies-literature

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