Small-Molecule Activation Mediated by [η5-1,3-(Me3Si)2C5H3]2U(bipy).

The uranium bipyridyl metallocene, [η5-1,3-(Me3Si)2C5H3]2U(bipy) (2), is readily accessible in good yield by adding potassium graphite (KC8) to a mixture of [η5-1,3-(Me3Si)2C5H3]2UCl2 (1) and 2,2'-bipyridine. Compound 2 was fully characterized and employed for small-molecule activation. It has been demonstrated that 2 may serve as a synthon for [η5-1,3-(Me3Si)2C5H3]2U(II) fragment in the presence of Ph2E2 (E = S, Se), alkynes, and a variety of hetero-unsaturated molecules such as diazabutadienes, azine (Ph2C═N)2, o-benzoquinone, pyridine N-oxide, CS2, isothiocyanates, and organic azides. However, upon exposure of 2 to thio-ketone Ph2CS, aldehyde p-MePhCHO, ketone Ph2CO, imine PhCH═NPh, azine (PhCH═N)2, and nitrile PhCN, it may also promote C-C coupling reactions forming [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(Ph2CS)] (16), [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(p-MePhCHO)] (17), [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(Ph2CO)] (18), [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(PhCHNPh)] (19), [η5-1,3-(Me3Si)2C5H3]2U[(bipy)(PhCHNN═CHPh)] (20), and [η5-1,3-(Me3Si)2C5H3]2U[(N2C10H7C(Ph)NH)] (22), respectively, in quantitative conversion. Furthermore, in the presence of CuI, a single-electron transfer (SET) process is observed to yield the uranium(III) iodide complex [η5-1,3-(Me3Si)2C5H3]2U(I)(bipy) (15).

[1]  R. D. Britt,et al.  A Uranium(II) Arene Complex That Acts as a Uranium(I) Synthon. , 2021, Journal of the American Chemical Society.

[2]  M. Zeller,et al.  Using Redox-Active Ligands to Generate Actinide Ligand Radical Species. , 2021, Inorganic chemistry.

[3]  M. Zeller,et al.  Elucidation of Thorium Redox-Active Ligand Complexes: Evidence for a Thorium-Tri(radical) Species. , 2021, Inorganic chemistry.

[4]  Marc D. Walter,et al.  Influence of the 1,3-Bis(trimethylsilyl)cyclopentadienyl Ligand on the Reactivity of the Uranium Phosphinidene [η5-1,3-(Me3Si)2C5H3]2U(═P-2,4,6-iPr3C6H2)(OPPh3) , 2021, Organometallics.

[5]  M. Walter,et al.  Uranium versus Thorium: Synthesis and Reactivity of [η 5‐1,2,4‐(Me3C)3C5H2]2U[η 2‐C2Ph2] , 2021, Chemistry.

[6]  Wenliang Huang,et al.  Arene-Bridged Dithorium Complexes: Inverse Sandwiches Supported by a δ Bonding Interaction. , 2020, Journal of the American Chemical Society.

[7]  L. Maron,et al.  Delivery of a Masked Uranium(II) by an Oxide-Bridged Diuranium(III) Complex. , 2020, Angewandte Chemie.

[8]  Marc D. Walter,et al.  Experimental and Computational Studies on a Base‐Free Terminal Uranium Phosphinidene Metallocene , 2020, Chemistry.

[9]  Fu-Sheng Guo,et al.  Isolation of a Perfectly Linear Uranium(II) Metallocene. , 2019, Angewandte Chemie.

[10]  M. P. Shores,et al.  Synthesis and Characterization of a Neutral U(II) Arene Sandwich Complex. , 2018, Journal of the American Chemical Society.

[11]  J. Ziller,et al.  Chelate-Free Synthesis of the U(II) Complex, [(C5H3(SiMe3)2)3U]1-, Using Li and Cs Reductants and Comparative Studies of La(II) and Ce(II) Analogs. , 2018, Inorganic chemistry.

[12]  B. Scott,et al.  Identification of the Formal +2 Oxidation State of Neptunium: Synthesis and Structural Characterization of {NpII[C5H3(SiMe3)2]3}1. , 2018, Journal of the American Chemical Society.

[13]  J. Arnold,et al.  Reductive Elimination of Diphosphine from a Thorium–NHC–Bis(phosphido) Complex , 2017 .

[14]  B. Scott,et al.  Identification of the Formal +2 Oxidation State of Plutonium: Synthesis and Characterization of {PuII[C5H3(SiMe3)2]3}. , 2017, Journal of the American Chemical Society.

[15]  Marc D. Walter,et al.  Small-Molecule Activation Mediated by a Uranium Bipyridyl Metallocene , 2017 .

[16]  F. Heinemann,et al.  Molecular and Electronic Structures of Eight-Coordinate Uranium Bipyridine Complexes: A Rare Example of a Bipy2- Ligand Coordinated to a U4+ Ion. , 2017, Inorganic chemistry.

[17]  Justin K. Pagano,et al.  Synthesis and characterization of a new and electronically unusual uranium metallacyclocumulene, (C 5 Me 5 ) 2 U(η 4 -1,2,3,4-PhC 4 Ph) , 2017 .

[18]  L. Maron,et al.  Carbon-Nitrogen Bond Cleavage by a Thorium-NHC-bpy Complex. , 2016, Angewandte Chemie.

[19]  L. Maron,et al.  A New Supporting Ligand in Actinide Chemistry Leads to Reactive Bis(NHC)borate-Supported Thorium Complexes , 2016 .

[20]  M. Ephritikhine.  Molecular actinide compounds with soft chalcogen ligands , 2016 .

[21]  Marc D. Walter,et al.  Preparation of (η5-C5Me5)2Th(bipy) and Its Reactivity toward Small Molecules , 2016 .

[22]  Marc D. Walter,et al.  Influence of the 5f Orbitals on the Bonding and Reactivity in Organoactinides: Experimental and Computational Studies on a Uranium Metallacyclopropene. , 2016, Journal of the American Chemical Society.

[23]  J. Ziller,et al.  Expanding Thorium Hydride Chemistry Through Th²⁺, Including the Synthesis of a Mixed-Valent Th⁴⁺/Th³⁺ Hydride Complex. , 2016, Journal of the American Chemical Society.

[24]  Justin K. Pagano,et al.  Tuning the Oxidation State, Nuclearity, and Chemistry of Uranium Hydrides with Phenylsilane and Temperature: The Case of the Classic Uranium(III) Hydride Complex [(C5Me5)2U(μ-H)]2 , 2016 .

[25]  Kamran B. Ghiassi,et al.  [U(bipy)4 ]: A Mistaken Case of U0 ? , 2016, Chemistry.

[26]  Katie R. Meihaus,et al.  Expanding the Chemistry of Molecular U(2+) Complexes: Synthesis, Characterization, and Reactivity of the {[C5 H3 (SiMe3 )2 ]3 U}(-) Anion. , 2016, Chemistry.

[27]  Marc D. Walter,et al.  Experimental and Computational Studies on an Actinide Metallacyclocumulene Complex , 2015 .

[28]  M. Zeller,et al.  Synthesis, Characterization, and Stoichiometric U-O Bond Scission in Uranyl Species Supported by Pyridine(diimine) Ligand Radicals. , 2015, Journal of the American Chemical Society.

[29]  S. Liddle.  The Renaissance of Non-Aqueous Uranium Chemistry. , 2015, Angewandte Chemie.

[30]  K. Lyssenko,et al.  Ytterbium(III) Complexes Coordinated by Dianionic 1,4-Diazabutadiene Ligands , 2015 .

[31]  S. Odoh,et al.  Investigation of the electronic ground states for a reduced pyridine(diimine) uranium series: evidence for a ligand tetraanion stabilized by a uranium dimer. , 2015, Journal of the American Chemical Society.

[32]  P. Arnold,et al.  C-H bond activation by f-block complexes. , 2015, Angewandte Chemie.

[33]  P. Fanwick,et al.  Harnessing redox activity for the formation of uranium tris(imido) compounds. , 2014, Nature chemistry.

[34]  W. Hieringer,et al.  Synthesis and characterization of a uranium(II) monoarene complex supported by δ backbonding. , 2014, Angewandte Chemie.

[35]  M. Ephritikhine,et al.  Thorocene adducts of the neutral 2,2′-bipyridine and its radical anion. Synthesis and crystal structures of [Th(η8-C8H8)2(κ2-bipy)] and [Th(μ-η8:η5-C8H8)2(κ2-bipy)K(py)2]∞ , 2014 .

[36]  Guofu Zi.  Organothorium complexes containing terminal metal-ligand multiple bonds , 2014, Science China Chemistry.

[37]  P. Fanwick,et al.  Multielectron C-O bond activation mediated by a family of reduced uranium complexes. , 2014, Inorganic chemistry.

[38]  J. Ziller,et al.  Identification of the +2 oxidation state for uranium in a crystalline molecular complex, [K(2.2.2-cryptand)][(C5H4SiMe3)3U]. , 2013, Journal of the American Chemical Society.

[39]  S. Liddle,et al.  Small‐Molecule Activation at Uranium(III) , 2013 .

[40]  C. Barnes,et al.  Bringing Redox Reactivity to a Redox Inactive Metal Center – E–I (E = C, Si) Bond Cleavage with a Thorium Bis(α-diimine) Complex , 2013 .

[41]  M. Ephritikhine,et al.  Revisiting the chemistry of the actinocenes [(η8-C8H8)2An] (An = U, Th) with neutral Lewis bases. Access to the bent sandwich complexes [(η8-C8H8)2An(L)] with thorium (L = py, 4,4'-bipy, tBuNC, R4phen). , 2013, Journal of the American Chemical Society.

[42]  Trevor W. Hayton.  Uranium chemistry: an actinide milestone. , 2013, Nature chemistry.

[43]  M. Ephritikhine.  Recent Advances in Organoactinide Chemistry As Exemplified by Cyclopentadienyl Compounds , 2013 .

[44]  Trevor W. Hayton,et al.  Recent developments in actinide-ligand multiple bonding. , 2013, Chemical communications.

[45]  Bess Vlaisavljevich,et al.  Investigations of the Electronic Structure of Arene-Bridged Diuranium Complexes , 2013 .

[46]  W. Lukens,et al.  Is the bipyridyl thorium metallocene a low-valent thorium complex? A combined experimental and computational study , 2013 .

[47]  Marc D. Walter,et al.  A bipyridyl thorium metallocene: synthesis, structure and reactivity. , 2012, Dalton transactions.

[48]  L. Gagliardi,et al.  Computational insights into uranium complexes supported by redox-active α-diimine ligands. , 2012, Inorganic chemistry.

[49]  K. Meyer,et al.  Uranium-mediated carbon dioxide activation and functionalization , 2012 .

[50]  Marc D. Walter,et al.  Synthesis, Structure, and Reactivity of a Thorium Metallocene Containing a 2,2′-Bipyridyl Ligand , 2012 .

[51]  K. Meyer,et al.  Hydrogenation of CO at a uranium(III) center. , 2011, Angewandte Chemie.

[52]  P. Arnold.  Uranium-mediated activation of small molecules. , 2011, Chemical communications.

[53]  J. M. Kikkawa,et al.  Synthesis, characterization, and multielectron reduction chemistry of uranium supported by redox-active α-diimine ligands. , 2011, Inorganic chemistry.

[54]  A. G. Moody,et al.  Ring folding in cyclopentadienyl diazabutadiene complexes of group 4 and 5 transition metals , 2011 .

[55]  B. Scott,et al.  A general and modular synthesis of monoimidouranium(IV) dihalides. , 2011, Inorganic chemistry.

[56]  J. Ziller,et al.  Reduction chemistry of the mixed ligand metallocene [(C5Me5)(C8H8)U]2(μ-C8H8) with bipyridines , 2010 .

[57]  P. Fanwick,et al.  Crystallographic evidence of a base-free uranium(IV) terminal oxo species. , 2010, Inorganic chemistry.

[58]  B. Scott,et al.  Actinide redox-active ligand complexes: reversible intramolecular electron-transfer in U(dpp-BIAN)2/U(dpp-BIAN)2(THF). , 2010, Inorganic chemistry.

[59]  B. Scott,et al.  Comparative study of f-element electronic structure across a series of multimetallic actinide and lanthanoid-actinide complexes possessing redox-active bridging ligands. , 2010, Inorganic chemistry.

[60]  S. Gambarotta,et al.  Attempting to Reduce the Irreducible: Preparation of a Rare Paramagnetic Thorium Species , 2010 .

[61]  P. Fanwick,et al.  Synthesis and characterization of a uranium(III) complex containing a redox-active 2,2'-bipyridine ligand. , 2010, Inorganic chemistry.

[62]  B. Scott,et al.  Oxidative addition to U(V)-U(V) dimers: facile routes to uranium(VI) bis(imido) complexes. , 2009, Inorganic chemistry.

[63]  J. Ziller,et al.  Synthesis of heteroleptic uranium (mu-eta(6):eta(6)-C6H6)2- sandwich complexes via facile displacement of (eta(5)-C5Me5)1- by ligands of lower hapticity and their conversion to heteroleptic bis(imido) compounds. , 2009, Journal of the American Chemical Society.

[64]  C. Anthon,et al.  Influence of steric pressure on the activation of carbon dioxide and related small molecules by uranium coordination complexes. , 2009, Dalton transactions.

[65]  S. Gambarotta,et al.  Reduced uranium complexes: synthetic and DFT study of the role of pi ligation in the stabilization of uranium species in a formal low-valent state. , 2009, Journal of the American Chemical Society.

[66]  Robyn L. Gdula,et al.  Cation-cation interactions, magnetic communication, and reactivity of the pentavalent uranium ion [U(NtBu)2]+. , 2009, Angewandte Chemie.

[67]  Marc D. Walter,et al.  Decamethylytterbocene complexes of bipyridines and diazabutadienes: multiconfigurational ground states and open-shell singlet formation. , 2009, Journal of the American Chemical Society.

[68]  C. Cummins,et al.  Towards uranium catalysts , 2008, Nature.

[69]  C. Raston,et al.  Reactivity variations within Group 4 complexes of 1,4-di-tert-butyl-1,4-diazabuta-1,3-diene: Structures of [(C5H5)TiCl{(t-BuNCH)2}] and [(C5H5)2Zr{(t-BuNCH)2}] , 2008 .

[70]  J. Ziller,et al.  Actinide Hydride Complexes as Multielectron Reductants: Analogous Reduction Chemistry from [(C5Me5)2UH]2, [(C5Me5)2UH2]2, and [(C5Me5)2ThH2]2 , 2007 .

[71]  M. Walter,et al.  Coordination of 1,4-Diazabutadiene Ligands to Decamethylytterbocene: Additional Examples of Spin Coupling in Ytterbocene Complexes , 2007 .

[72]  S. Gambarotta,et al.  Ring opening and C-O and C-N bond cleavage by transient reduced thorium species , 2006 .

[73]  M. Ephritikhine.  The vitality of uranium molecular chemistry at the dawn of the XXIst century. , 2006, Dalton transactions.

[74]  E. Barnea,et al.  Organoactinides in catalysis , 2006 .

[75]  M. Ephritikhine,et al.  Lanthanide(III)/actinide(III) differentiation in the cerium and uranium complexes [M(C5Me5)2(L)]0,+ (L=2,2'-bipyridine, 2,2':6',2''-terpyridine): structural, magnetic, and reactivity studies. , 2005, Chemistry.

[76]  J. Ziller,et al.  [(C5Me5)2U][(μ-Ph)2BPh2] as a four electron reductant , 2005 .

[77]  M. Walter,et al.  Preparation and Reactions of Base-Free Bis(1,2,4-tri-tert-butylcyclopentadienyl)uranium Oxide, Cp‘2UO , 2005 .

[78]  S. Gambarotta,et al.  Ligand Metallation during the Reduction of a Thorium(IV) Amide Complex , 2005 .

[79]  S. Gambarotta,et al.  Cyclometalation and solvent deoxygenation during reduction of a homoleptic Th(OAr)4 complex: Serendipitous formation of a terminally bonded Th-OH function , 2004 .

[80]  J. Ziller,et al.  Structure, reactivity, and density functional theory analysis of the six-electron reductant, [(C5Me5)2U]2(mu-eta6:eta6-C6H6), synthesized via a new mode of (C5Me5)3M reactivity. , 2004, Journal of the American Chemical Society.

[81]  L. Maria,et al.  The role of neutral coligands on the stabilization of mono-Tp(i)Pr2 U(III) complexes. , 2004, Inorganic chemistry.

[82]  S. Gambarotta,et al.  Amide from dinitrogen by in situ cleavage and partial hydrogenation promoted by a transient zero-valent thorium synthon. , 2003, Angewandte Chemie.

[83]  S. Gambarotta,et al.  The first thorium arene complex: a divalent synthon. , 2003, Angewandte Chemie.

[84]  C. Cummins,et al.  Diuranium inverted sandwiches involving naphthalene and cyclooctatetraene. , 2002, Journal of the American Chemical Society.

[85]  M. Ephritikhine,et al.  Complexation studies of iodides of trivalent uranium and lanthanides (Ce and Nd) with 2,2'-bipyridine in anhydrous pyridine solutions. , 2001, Inorganic chemistry.

[86]  P. Arnold,et al.  Arene-Bridged Diuranium Complexes: Inverted Sandwiches Supported by δ Backbonding , 2000 .

[87]  W. Lukens,et al.  Solution structure and behavior of dimeric uranium(III) metallocene halides , 1999 .

[88]  Laura L. Blosch,et al.  Preparation, Solution Behavior, and Solid-State Structures of (1,3-R2C5H3)2UX2, Where R Is CMe3 or SiMe3 and X Is a One-Electron Ligand , 1999 .

[89]  W. Lukens,et al.  Structures of substituted-cyclopentadienyl uranium(III) dimers and related uranium metallocenes deduced by EXAFS , 1999 .

[90]  A. Spannenberg,et al.  Reactions of 1,4- and 2,3-Diazadienes with Titanocene and Zirconocene Complexes of Bis(trimethylsilyl)acetylene: Acetylene Coupling or Substitution Including Subsequent C−H Activation, C−C Coupling, and N−N Cleavage to Heterobimetallic Complexes , 1998 .

[91]  Laura L. Blosch,et al.  OXIDATIVE ELIMINATION OF H2 FROM CP'2U(MU -OH)2 TO FORM CP'2U(MU -O)2, WHERE CP' IS 1,3-(ME3C)2C5HI3 OR 1,3-(ME3SI)2C5H3 , 1996 .

[92]  N. Kaltsoyannis.  Covalency in metal complexes of 1,4-diazabutadiene (dab). A density functional investigation of the electronic structures of [M(dab)2](M = Li, Ga or Co) and [Th(NH3)(NH2)3(dab)] , 1996 .

[93]  P. Hitchcock,et al.  Synthesis, structure and electrochemistry of a paramagnetic (1,4-diazabutadiene)thorium complex , 1995 .

[94]  M. Nierlich,et al.  Interaction between Uranium(V) and -(VI) Fluorides and Nitrogen Bases. Characterization and Crystal Structures of the Dimorphic Adduct UF5.cntdot.bipy (bipy = 2,2'-Bipyridyl) , 1994 .

[95]  Wayne H. Smith,et al.  Synthesis of mixed-ring organoactinide complexes. 2. (Cyclooctatetraene)(pentamethylcyclopentadienyl)(THF)uranium [(C8H8)(C5Me5)U(THF)] and its 4,4'-dimethyl-2,2'-bipyridine derivative , 1993 .

[96]  A. Dietrich,et al.  Titanocen‐ und Zirconocen(diazadien)‐Komplexe: Darstellung, Charakterisierung und Struktur , 1990 .

[97]  L. Hegedus,et al.  Improved synthesis of (aminocarbene)chromium(0) complexes with use of C8K-generated Cr(CO)52-. Multivariant optimization of an organometallic reaction , 1990 .