Multi-electron reduction of sulfur and carbon disulfide using binuclear uranium(III) borohydride complexes

被引:29
作者
Arnold, Polly L. [1 ]
Stevens, Charlotte J. [1 ]
Bell, Nicola L. [1 ]
Lord, Rianne M. [1 ]
Goldberg, Jonathan M. [2 ]
Nichol, Gary S. [1 ]
Love, Jason B. [1 ]
机构
[1] Univ Edinburgh, EaStCHEM Sch Chem, Kings Bldg, Edinburgh EH9 3JF, Midlothian, Scotland
[2] Univ Washington, Dept Chem, Box 351700, Seattle, WA 98195 USA
基金
美国国家科学基金会; 英国工程与自然科学研究理事会;
关键词
SMALL-MOLECULE ACTIVATION; ELECTRON-TRANSFER REACTIONS; CHALCOGEN-ATOM-TRANSFER; X-RAY-DIFFRACTION; E-U E; CRYSTAL-STRUCTURE; METALLOCENES SYNTHESIS; SUPPORTING LIGANDS; STARTING MATERIALS; TRIVALENT URANIUM;
D O I
10.1039/c7sc00382j
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
The first use of a dinuclear U-III/U-III complex in the activation of small molecules is reported. The octadentate Schiff-base pyrrole, anthracene-hinged 'Pacman' ligand L-A combines two strongly reducing U-III centres and three borohydride ligands in [M(THF)(4)][{U(BH4)}(2)(mu-BH4)(L-A)(THF)(2)] 1-M, (M = Li, Na, K). The two borohydride ligands bound to uranium outside the macrocyclic cleft are readily substituted by aryloxide ligands, resulting in a single, weakly-bound, encapsulated endo group 1 metal borohydride bridging the two U-III centres in [{U(OAr)}(2)(mu-MBH4)(L-A)(THF)(2)] 2-M (OAr = (OC6H2Bu3)-Bu-t-2,4,6, M = Na, K). X-ray crystallographic analysis shows that, for 2-K, in addition to the endo-BH4 ligand the potassium counter-cation is also incorporated into the cleft through eta(5)-interactions with the pyrrolides instead of extraneous donor solvent. As such, 2-K has a significantly higher solubility in non-polar solvents and a wider U-U separation compared to the 'ate' complex 1. The cooperative reducing capability of the two U-III centres now enforced by the large and relatively flexible macrocycle is compared for the two complexes, recognising that the borohydrides can provide additional reducing capability, and that the aryloxide-capped 2-K is constrained to reactions within the cleft. The reaction between 1-Na and S-8 affords an insoluble, presumably polymeric paramagnetic complex with bridging uranium sulfides, while that with CS2 results in oxidation of each U-III to the notably high U-V oxidation state, forming the unusual trithiocarbonate (CS3)(2-) as a ligand in [{U(CS3)}(2)(mu-kappa(2):kappa(2)-CS3)(L-A)](4). The reaction between 2-K and S8 results in quantitative substitution of the endo-KBH4 by a bridging persulfido (S-2)(2-) group and oxidation of each U-III to U-IV, yielding [{U(OAr)}(2)(mu-kappa(2):kappa(2)-S-2)(L-A)] (5). The reaction of 2-K with CS2 affords a thermally unstable adduct which is tentatively assigned as containing a carbon disulfido (CS2)(2-) ligand bridging the two U centres (6a), but only the mono-bridged sulfido (S)(2-) complex [{U(OAr)}(2)(mu-S)(L-A)] (6) is isolated. The persulfido complex (5) can also be synthesised from the mono-bridged sulfido complex (6) by the addition of another equivalent of sulfur.
引用
收藏
页码:3609 / 3617
页数:9
相关论文
共 75 条
  • [1] Lanthanide(III) and Actinide(III) Complexes [M(BH4)2(THF)5][BPh4] and [M(BH4)2(18-crown-6)][BPh4] (M = Nd, Ce, U): Synthesis, Crystal Structure, and Density Functional Theory Investigation of the Covalent Contribution to Metal-Borohydride Bonding
    Arliguie, Therese
    Belkhiri, Lotfi
    Bouaoud, Salah-Eddine
    Thuery, Pierre
    Villiers, Claude
    Boucekkine, Abdou
    Ephritikhine, Michel
    [J]. INORGANIC CHEMISTRY, 2009, 48 (01) : 221 - 230
  • [2] Characterizing Pressure-Induced Uranium CH Agostic Bonds
    Arnold, Polly L.
    Prescimone, Alessandro
    Farnaby, Joy H.
    Mansell, Stephen M.
    Parsons, Simon
    Kaltsoyannis, Nikolas
    [J]. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 2015, 54 (23) : 6735 - 6739
  • [3] New Chemistry from an Old Reagent: Mono- and Dinuclear Macrocyclic Uranium(III) Complexes from (U(BH4)3(THF)2)
    Arnold, Polly L.
    Stevens, Charlotte J.
    Farnaby, Joy H.
    Gardiner, Michael G.
    Nichol, Gary S.
    Love, Jason B.
    [J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2014, 136 (29) : 10218 - 10221
  • [4] Switchable π-coordination and C-H metallation in small-cavity macrocyclic uranium and thorium complexes
    Arnold, Polly L.
    Farnaby, Joy H.
    White, Rebecca C.
    Kaltsoyannis, Nikolas
    Gardiner, Michael G.
    Love, Jason B.
    [J]. CHEMICAL SCIENCE, 2014, 5 (02) : 756 - 765
  • [5] Uranium-mediated activation of small molecules
    Arnold, Polly L.
    [J]. CHEMICAL COMMUNICATIONS, 2011, 47 (32) : 9005 - 9010
  • [6] Ligand Modifications for Tailoring the Binuclear Microenvironments in Schiff-Base Calixpyrrole Pacman Complexes
    Askarizadeh, Elham
    Devoille, Aline M. J.
    Boghaei, Davar M.
    Slawin, Alexandra M. Z.
    Love, Jason. B.
    [J]. INORGANIC CHEMISTRY, 2009, 48 (15) : 7491 - 7500
  • [7] ELECTRON-TRANSFER REACTIONS OF DIVALENT YTTERBIUM METALLOCENES SYNTHESIS OF THE SERIES [(ME5C5)2YB]2[MU-O],[MU-S],[MU-SE],[MU-TE] AND CRYSTAL-STRUCTURE OF [(ME5C5)2YB]2[MU-SE]
    BERG, DJ
    BURNS, CJ
    ANDERSEN, RA
    ZALKIN, A
    [J]. ORGANOMETALLICS, 1989, 8 (08) : 1865 - 1870
  • [8] SYNTHESIS AND CRYSTAL-STRUCTURE OF THE OXO-BRIDGED BIMETALLIC ORGANOURANIUM COMPLEX [(ME3SIC5H4)3U]2[MU-O]
    BERTHET, JC
    LEMARECHAL, JF
    NIERLICH, M
    LANCE, M
    VIGNER, J
    EPHRITIKHINE, M
    [J]. JOURNAL OF ORGANOMETALLIC CHEMISTRY, 1991, 408 (03) : 335 - 341
  • [9] BINDER H, 1982, Z NATURFORSCH B, V37, P1548
  • [10] [(BH2)6S4]2-, [(BH2)6SE4]2- - NEW CHALCOGENOBORON HYDRIDE ANIONS WITH ADAMANTANE STRUCTURE
    BINDER, H
    LOOS, H
    DERMENTZIS, K
    BORRMANN, H
    SIMON, A
    [J]. CHEMISCHE BERICHTE, 1991, 124 (03) : 427 - 432