Uranium and Thorium Complexes of the Phosphaethynolate Ion† Cite This: Chem

Total Page:16

File Type:pdf, Size:1020Kb

Uranium and Thorium Complexes of the Phosphaethynolate Ion† Cite This: Chem Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue Uranium and thorium complexes of the phosphaethynolate ion† Cite this: Chem. Sci.,2015,6,6379 a a b c Clement´ Camp, Nicholas Settineri, Julia Lef`evre, Andrew R. Jupp, c b a Jose´ M. Goicoechea, Laurent Maron* and John Arnold* New tris-amidinate actinide (Th, U) complexes containing a rare O-bound terminal phosphaethynolate (OCPÀ) ligand were synthesized and fully characterized. The cyanate (OCNÀ) and thiocyanate (SCNÀ) Received 14th June 2015 analogs were prepared for comparison and feature a preferential N-coordination to the actinide metals. Accepted 17th July 2015 The Th(amid)3(OCP) complex reacts with Ni(COD)2 to yield the heterobimetallic adduct (amid)3Th(m- DOI: 10.1039/c5sc02150b h1(O):h2(C,P)-OCP)Ni(COD) featuring an unprecedented reduced (OCPÀ) bent fragment bridging the two www.rsc.org/chemicalscience metals. À Efficient synthetic routes to the phosphaethynolate ion (OCP ) – counterparts, as well as determining the reactivity prole of the Creative Commons Attribution 3.0 Unported Licence. the phosphorus analog of the cyanate anion – only appeared M-bound phosphaethynolate species. 1,2 2 recently. Since then, reports by the Grutzmacher¨ and Goi- We therefore targeted the use of Na(OCP)(dioxane)n as a À À coechea groups have shown that OCP exhibits a rich cycloaddi- source of the OCP ligand in order to explore its coordination tion and redox chemistry which allowed the synthesis of a variety properties with actinides. We reasoned that these oxophilic À of phosphorus-containing organic derivatives.1,3–8 Particular metals were suitable candidates to polarize the OCP moiety. À interest arises from two recent studies which showed that OCP Interaction of heteroallenes with actinide species has attracted could act as a P-transfer reagent when treated with imidazolium substantial interest over the past few years notably due to the salts9 or cyclotrisilene,10 suggesting that phosphaethynolate could propensity of low-valent actinides to activate small molecules 15–22 20,23–26 27–33 This article is licensed under a be used as a convenient phosphide source. Recent computational (CO2, CS2, azides ). Original uranium-mediated studies also predicted the possibility to generate transition metal formations of cyanate involving reductive co-coupling of CO phosphides from M-PCO precursors through carbonyl loss.11 and NO34,35 and carbonylation of terminal nitrido36 or silyli- However the high reactivity of this anion can be difficult to control mido37 uranium derivatives have also been described. Here we Open Access Article. Published on 20 July 2015. Downloaded 6/19/2018 11:46:25 AM. and generally yields diverse, unwanted decomposition products.12 report a series of uranium and thorium tris-amidinate À À À This likely explains why thus far only a single example of a complexes featuring linear OCP , OCN and SCN ligands as phosphaethynolate transition metal complex has been docu- well as preliminary reactivity studies involving the actinide- mented, Re(P]C]O)(CO)2(triphos) (triphos ¼ MeC(CH3- bound phosphaethynolate moiety with Ni(0). 12 À PPh2)3), featuring a terminal (OCP ) ligand which is P-bound to Salt-metathesis reactions between the tris-amidinate chloride 38 0 Re(I) and strongly bent around the pnictogen center (Fig. 1). While precursors MCl(amid)3 (1 M ¼ U ; 2 M ¼ Th; amid ¼ N,N -bis- À recent work by Grutzmacher¨ and coworkers has shown that OCP (trimethylsilyl)benzamidinate) and Na(OCP)(dioxane)2.9 affords 13 possesses an ambident nucleophilicity, several questions the desired phosphaethynolate complexes M(OCP)(amid)3 (3 M ¼ remain to be answered concerning its interaction with metal U; 4 M ¼ Th) as block-shaped crystals in 76% and 63% isolated centers and how this compares with its cyanate and thiocyanate yields, respectively (Scheme 1). Both compounds exhibit 1HNMR resonance patterns in agreement with C3-symmetric solution 31 species. The P NMR resonance for the OCP moiety in 4 (C6D6, 293 K) is signicantly shied downeld (d ¼334 ppm) compared aHeavy Element Chemistry Group, Chemical Sciences Division, Lawrence Berkeley 12 to that reported for Re(P]C]O)(CO)2(triphos) (d ¼398 ppm) National Laboratory and Department of Chemistry, University of California, Berkeley, California 94720, USA. E-mail: [email protected] bLPCNO, Universit´e de Toulouse, INSA Toulouse, 135 Avenue de Rangueil, 31077 Toulouse, France. E-mail: [email protected] cDepartment of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK. E-mail: [email protected] † Electronic supplementary information (ESI) available: Experimental details, NMR and IR spectra, crystallographic details and les in CIF format, Fig. 1 Left: structure of Re(PCO)(CO)2(triphos) (triphos ¼ MeC(CH3- – 14 À computational data. CCDC 1406759 1406765. For ESI and crystallographic data PPh2)3). Right: resonance structures for the OCP anion. in CIF or other electronic format see DOI: 10.1039/c5sc02150b This journal is © The Royal Society of Chemistry 2015 Chem. Sci.,2015,6,6379–6384 | 6379 View Article Online Chemical Science Edge Article Creative Commons Attribution 3.0 Unported Licence. Scheme 1 Synthesis of complexes M(OCP)(amid)3 (3 M ¼ U; 4 M ¼ Th), M(OCN)(amid)3 (5 M ¼ U; 6 M ¼ Th), and M(SCN)(amid)3 (7 M ¼ U; 8 M ¼ Th). TMS ¼ SiMe3. and alkali and alkaline earth phosphaethynolate salts (d(31P) range: À362 to À397 ppm).1,2,39 Due to the paramagnetism of the This article is licensed under a 31 U(IV)center,the PNMRsignalfor3 is observed at even higher frequency (d ¼285 ppm). Compounds 3 and 4 feature strong IR À absorption bands at almost identical wavenumbers (1685 cm 1 for Fig. 2 Solid-state molecular structures of compounds 3 (top), 5 Open Access Article. Published on 20 July 2015. Downloaded 6/19/2018 11:46:25 AM. À ff 3; 1683 cm 1 for 4) corresponding to the C–O stretching vibra- (middle) and 7 (bottom) determined by single-crystal X-ray di raction. À Ellipsoids are represented with 50% probability. Metrical parameters tional mode of the OCP ligand.Thisfeatureappearsatlower are reported in ESI.† ] ] À1 energy than that found in Re(P C O)(CO)2(triphos) (1860 cm ) À À1 and alkali OCP salts (1730 to 1780 cm ), which indicates – position. The O–C–P (179.1(4) in 3; 179.7(4) in 4) and An–O–C weakeningoftheCO bond order. As evidenced both by the 31 (170.9(3) in 3; 176.4(3) in 4) angles are close to linearity. The low wavenumber IR absorption of nC–O and the downeld P À ^ ˚ 3 ˚ 4 – ˚ 3 NMR chemical shi,theOCP moiety in 3 and 4 is best C P (1.576(5) Ain ; 1.561(4) Ain ) and C O (1.219(6) Ain ; ˚ 4 described as a phosphaalkyne-type limiting resonance structure 1.246(4) Ain ) bond lengths are in the expected range (for ^ ¼ ˚ – ˚ (see Fig. 1) in contrast with the P-bound phosphaketene-type comparison C P 1.579(3) A; C O 1.212(4) A in [K([18]crown- 1 ^ Re(P]C]O)(CO) (triphos)12 species. Altogether, these spectro- 6)][PCO]), with a strengthening of the C P triple bond and a 2 – scopic data suggest substantial strengthening of the C^Pbond weakening of the C O bond when compared with the metrical À ^ ¼ ˚ – upon coordination to the oxophilic actinide centers. parameters computed for the OCP anion (C P 1.625 A; C O À ˚ 12 – ˚ The O-coordination of the OCP fragment is conrmed by 1.203 A). The U O (2.297(3) A) bond length is slightly shorter – ˚ X-ray crystallography (Fig. 2-top). Complex 4 crystallized as two than that for Th O (2.318(2) A), which is consistent with the 40 independent molecules in the asymmetric unit, one of which larger ionic radius of Th(IV). Both distances are in the usual À featured an OCP group disordered over two positions with the range and fall in between those found in actinide complexes of – C^P motif pointing to two different directions in a 45 : 55 ratio. strongly donating aryloxide or siloxide ligands and An O dative 41–46 – – 4 interactions. The U Namid and Th Namid bond distances The discussion of metrical parameters for is, therefore, per- ˚ ˚ formed on the non-disordered molecule only. The thorium and average respectively 2.44(3) A and 2.49(3) A and compare well 38,47–49 uranium analogs adopt C -symmetry, with the three bidentate with related compounds. 3 5–8 amidinate ligands wrapping around the actinide in a propeller- The cyanate and thiocyanate counterparts (Scheme 1) À like geometry, and the OCP ligand pointing in the axial were prepared similarly, allowing a direct comparison of 6380 | Chem. Sci.,2015,6,6379–6384 This journal is © The Royal Society of Chemistry 2015 View Article Online Edge Article Chemical Science structurally analogous compounds. The 1H NMR patterns for NBO analysis of 4 indicates that the O-bound complex is these species are like those of compounds 1–4, in agreement preferred over the P-bound analog because of the donation from with An(IV) symmetric species in solution. The IR C–N stretches the lone pairs of the oxygen atom to the empty hybrid d/f orbital À À À for compounds 5–8 (2199 cm 1 in 5, 2200 cm 1 in 6, 2021 cm 1 of the metal (Wiberg index of 0.42). It is worthy to note that À in 7 and 2018 cm 1 in 8) are of high intensities and fall in the there is no interaction between the C–P and the C–O bonds; the À range of previously reported N-bound cyanate36,37,50 and thiocy- molecular orbitals within the OCP unit are localized onto À anate51,52 actinide compounds.
Recommended publications
  • Synthesis and Decarbonylation Chemistry of Gallium Phosphaketenes† Cite This: Dalton Trans., 2020, 49, 15249 Daniel W
    Dalton Transactions View Article Online PAPER View Journal | View Issue Synthesis and decarbonylation chemistry of gallium phosphaketenes† Cite this: Dalton Trans., 2020, 49, 15249 Daniel W. N. Wilson,a William K. Myers b and Jose M. Goicoechea *a A series of gallium phosphaketenyl complexes supported by a 1,2-bis(aryl-imino)acenaphthene ligand (Dipp-Bian) are reported. Photolysis of one such species induced decarbonylation to afford a gallium sub- Received 10th September 2020, stituted diphosphene. Addition of Lewis bases, specifically trimethylphosphine and the gallium carbenoid Accepted 12th October 2020 i Ga(Nacnac) (Nacnac = HC[C(Me)N-(C6H3)-2,6- Pr2]2), resulted in displacement of the phosphaketene car- DOI: 10.1039/d0dt03174g bonyl to yield base-stabilised phosphinidenes. In several of these transformations, the redox non-inno- rsc.li/dalton cence of the Dipp-Bian ligand was found to give rise to radical intermediates and/or side-products. − The 2-phosphaethynolate anion (PCO ), a heavy analogue the phosphorus atom. The polydentate character of the salen − Creative Commons Attribution 3.0 Unported Licence. of cyanate (NCO ), is a useful precursor for the synthesis ligand limits the further reactivity of these species, which of phosphorus-containing heterocycles and low valent behave indistinguishably from one another and in a compar- phosphorus compounds.1 Access to such species typically able manner to ionic phosphaethynolate salts of the alkali and involves salt metathesis reactions between [Na(dioxane)x][PCO] alkaline-earth elements. and halogen-containing compounds, resulting in O- or Group 13 phosphaethynolate compounds are promising P-substituted products. The latter coordination mode domi- candidates as precursors to molecules and materials with nates the elements of the d- and p-block, allowing access to interesting electronic properties.
    [Show full text]
  • Diphosphazide-Supported Trialkyl Thorium(IV) Complex Tara K
    pubs.acs.org/Organometallics Communication Diphosphazide-Supported Trialkyl Thorium(IV) Complex Tara K. K. Dickie, Ashraf A. Aborawi, and Paul G. Hayes* Cite This: Organometallics 2020, 39, 2047−2052 Read Online ACCESS Metrics & More Article Recommendations *sı Supporting Information ABSTRACT: The potassium salt of a new ligand, KLP=N3 (2, κ5 i i − LP=N3 = -2,5-[(4- PrC6H4)N3 P Pr2]2N(C4H2) ), that features two units of the rare phosphazide (RN3 PR3) functionality was synthesized via an incomplete Staudinger reaction between K[2,5- i i ( Pr2P)2N(C4H2)] (1)and4-PrC6H4N3. The diphosphazide ligand was transferred to a thorium(IV) metal center using salt metathesis strategies, yielding LP=N3ThCl3 (3), which contains two intact and coordinated phosphazides. Reaction of complex 3 with 3 equiv of LiCH2SiMe3 resulted in formation of the trialkyl thorium species LP=N3Th(CH2SiMe3)3 (4). In contrast, attempts to synthesize an organothorium complex supported by the previously κ3 reported bisphosphinimine ligand LP=N (LP=N = -2,5- i i − ff [(4- PrC6H4)N P Pr2]2N(C4H2) )aorded the cyclometalated * * κ4 i i i i 2− dialkyl complex L P=NTh(CH2SiMe3)2 (6,L PN = -2-[(4- PrC6H3)N P Pr2]-5-[(4- PrC6H4)N P Pr2]N(C4H2) ) and 1 equiv of free tetramethylsilane. 1 he Staudinger reaction, discovered in 1919, introduced the facile loss of N2, and, accordingly, were overlooked as ′ ’ T the formation of a phosphinimine group (R3P NR ) via viable functional groups in ligand design. Since Staudinger s the reaction of a tertiary phosphine (R3P) with an organic original work, multiple methods have been developed to ′ azide (N3R ), resulting in concomitant loss of N2.
    [Show full text]
  • Diverse Bonding Activations in the Reactivity of a Pentaphenylborole Toward Sodium Phosphaethynolate : Heterocycle Synthesis and Mechanistic Studies
    This document is downloaded from DR‑NTU (https://dr.ntu.edu.sg) Nanyang Technological University, Singapore. Diverse bonding activations in the reactivity of a pentaphenylborole toward sodium phosphaethynolate : heterocycle synthesis and mechanistic studies Li, Yan; Siwatch, Rahul Kumar; Mondal, Totan; Li, Yongxin; Ganguly, Rakesh; Koley, Debasis; So, Cheuk‑Wai 2017 Li, Y., Siwatch, R. K., Mondal, T., Li, Y., Ganguly, R., Koley, D., & So, C.‑W. (2017). Diverse bonding activations in the reactivity of a pentaphenylborole toward sodium phosphaethynolate : heterocycle synthesis and mechanistic studies. Inorganic chemistry, 56(7), 4112–4120. doi:10.1021/acs.inorgchem.7b00128 https://hdl.handle.net/10356/139442 https://doi.org/10.1021/acs.inorgchem.7b00128 This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.inorgchem.7b00128 Downloaded on 28 Sep 2021 11:54:28 SGT Diverse Bonding Activations in the Reactivity of a Pentaphenylborole toward Sodium Phosphaethynolate: Heterocycle Synthesis and Mechanistic Studies Yan Li,a Rahul Kumar Siwatch,a Totan Mondal,b Yongxin Li,a Rakesh Ganguly,a Debasis Koley*band Cheuk-Wai So*a aDivision of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore bDepartment of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741 246, India ABSTRACT The reaction of the pentaphenylborole [(PhC)4BPh] (1) with sodium phosphaethynolate·1,4- dioxane (NaOCP(1,4-dioxane)1.7) afforded the novel sodium salt of phosphaboraheterocycle 2.
    [Show full text]
  • Cycloaddition Chemistry of 2‐Phosphaethynolate Revealed By
    Angewandte Research Articles Chemie How to cite: Angew. Chem. Int. Ed. 2021, 60, 1197–1202 Cycloaddition Reactions International Edition: doi.org/10.1002/anie.202012506 German Edition: doi.org/10.1002/ange.202012506 The “Hidden” Reductive [2+2+1]-Cycloaddition Chemistry of 2-Phosphaethynolate Revealed by Reduction of a Th-OCP Linkage Jingzhen Du, Gbor Balzs, Ashley J. Wooles, Manfred Scheer,* and Stephen T. Liddle* Abstract: The reduction chemistry of the newly emerging coupling.[2] Furthermore, cycloaddition reactions of (OCP)À 2-phosphaethynolate (OCP)À is not well explored, and many under oxidising or neutral conditions have become well unanswered questions remain about this ligand in this context. established, producing a variety of novel three, four-, five-, or We report that reduction of [Th(TrenTIPS)(OCP)] (2, six-membered phosphorus heterocycles.[1] In contrast, the TIPS i 3À À [1, 3] Tren = [N(CH2CH2NSiPr 3)] ), with RbC8 via [2+2+1] reduction chemistry of (OCP) is in its infancy, but the cycloaddition, produces an unprecedented hexathorium com- clear picture already is that this closed-shell anion resists TIPS plex [{Th(Tren )}6(m-OC2P3)2(m-OC2P3H)2Rb4](5) featur- reduction, to avoid populating antibonding orbitals, inevita- ing four five-membered [C2P3] phosphorus heterocycles, which bly leading, when reduction can be effected, to spontaneous can be converted to a rare oxo complex [{Th(TrenTIPS)- fragmentation of the O-C-P unit in the majority of cases. (m-ORb)}2](6) and the known cyclometallated complex Indeed, this has been observed in many low-valent early i i [1,3] À [Th{N(CH2CH2NSiPr 3)2(CH2CH2SiPr 2CHMeCH2)}] (4)by d-block and f-block cases.
    [Show full text]
  • Novel Alkyne and Phosphaalkyne Coupling on an Ir4 Cluster: Synthesis and Molecular Structure of [Ir4(P-CO)(CO)7{P4-T13-Ph,PC(H)C(Ph)Pcbut}(P-Pph2)1 Maria Helena A
    View Article Online / Journal Homepage / Table of Contents for this issue J. CHEM. SOC., CHEM. COMMUN., 1994 1869 Novel Alkyne and Phosphaalkyne Coupling on an Ir4 Cluster: Synthesis and Molecular Structure of [Ir4(p-CO)(CO)7{p4-t13-Ph,PC(H)C(Ph)PCBut}(p-PPh2)1 Maria Helena A. Benvenutti,asb Peter B. Hitchcock,b John F. Nixon*b and Maria D. Vargas*d a lnstituto de Quimica, Universidade Estadual de Campinas, CP 6154, Campinas, 13083, SP, Brazil b School of Chemistry and Moiecular Sciences, University of Sussex, Brighton, UK BN 1 9QJ The cluster compound [(p-H)Ir4(CO),(Ph2PCCPh)(p-PPh2)]1 reacts with the phosphaalkyne ButCP to yield [Ir4(p-CO)(CO),{p~-113-Ph2PC(H)C(Ph)PCBut}(p-PPh2)]3, containing the novel 2-phosphabutadienylphosphine fragment as a result of the coupling of ButCP with the diphenylphosphinoalkyne ligand and incorporation of the cluster bound H atom. There are relatively few examples of controlled alkyne-alkyne between the Ph2PCCPh ligand and the ButCP molecule, and coupling reactions at polynuclear carbonyl clusters.' The hydride migration to the resulting new phosphorus carbon chemistry of phosphaalkynes, RCP, is of considerable con- chain were established by 'H, 31P and 13C NMR spectroscopy. temporary interest and their similarity to alkynes has been In spite of the detailed spectroscopic studies undertaken, it stressed previously.2 There is only one reported interaction was impossible to establish unambiguously the position of the between an alkyne and a phosphaalkyne, leading to a hydrogen atom in the chain, and whether the diphenylphos- mononuclear 774-1-phosphacyclobutadienecomplex described phinoalkyne had undergone P-C,, bond cleavage.
    [Show full text]
  • Intermediate Oxidation State Tungsten Acetylacetonate Complexes
    Intermediate Oxidation State Tungsten Acetylacetonate Complexes Chetna Khosla A dissertation submitted to the faculty of the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry. Chapel Hill 2009 Approved by: Advisor: Professor Joseph L. Templeton Reader: Professor Maurice Brookhart Reader: Professor Cynthia Schauer Professor Valerie Ashby Professor H. Holden Thorp ABSTRACT Chetna Khosla: INTERMEDIATE OXIDATION STATE TUNGSTEN ACETYLACETONATE COMPLEXES (Under the direction of Professor Joseph L. Templeton) Previous work with tungsten(II) acetylacetonate complexes has focused on synthesis of complexes with -bound ligands (alkyne, nitrile, imine, ketone, aldehyde). In this work, 2 addition of methyl triflate (MeOTf) to W(CO)(acac)2(η -N≡CPh) produces the iminoacyl 2 complex [W(CO)acac)2(η -MeN=CPh)][OTf]. Displacement of the carbon monoxide in 2 + [W(CO)(acac)2(η -MeN≡CPh)] by isonitriles, bulky phosphines, and alkynes has been accomplished. The substitution of carbon monoxide by alkyne relieves the iminoacyl ligand of its role as a four-electron donor and enables further reduction of the C-N based ligand. Use 2 + of Na[HB(OMe)3] as a hydride source that attacks [W(RC≡CR′)(acac)2(η -MeN=CPh)] 2 yields the imine complex W(RC≡CR′)(acac)2(η -MeN=CHPh) with a diastereoselective ratio of 2:1. Addition of MeOTf leads to the final tungsten(II) iminium complex 2 [W(RC≡CR′)(acac)2(η -Me2N=CHPh)][OTf]. 2 Addition of m-chloroperoxybenzoic acid (MCPBA) to W(CO)(acac)2(η -N≡CR) 2 2 results in oxidation of the metal center to form the W(IV) d metal complex W(O)(acac)2(η - N≡CR).
    [Show full text]
  • Lowcoordinated Silicon and Hypercoordinated Carbon
    Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 557 Lowcoordinated Silicon and Hypercoordinated Carbon Structure and Stability of Silicon Analogs of Alkenes and Carbon Analogs of Silicates ANDERS M. EKLÖF ACTA UNIVERSITATIS UPSALIENSIS ISSN 1651-6214 UPPSALA ISBN 978-91-554-7294-8 2008 urn:nbn:se:uu:diva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
    [Show full text]
  • Conjugated Low Coordinate Organophosphorus Materials
    CONJUGATED LOW COORDINATE ORGANOPHOSPHORUS MATERIALS: SYNTHESIS, CHARACTERIZATION AND PHOTOCHEMICAL STUDIES By VITTAL BABU GUDIMETLA Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Thesis Advisor: Dr. John D. Protasiewicz Department of Chemistry CASE WESTERN RESERVE UNIVERSITY January, 2010 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of _____________________________________________________ candidate for the ______________________degree *. (signed)_______________________________________________ (chair of the committee) ________________________________________________ ________________________________________________ ________________________________________________ ________________________________________________ ________________________________________________ (date) _______________________ *We also certify that written approval has been obtained for any proprietary material contained therein. Dedicated to my parents Table of Contents List of Tables………………………………………………………………………………i List of Figures…………………………………………………………………………….iii List of Charts…………………………………………………………………………….vii List of Schemes……………………………………………………………………………x List of Abbreviations…………………………………………………………………….xii Acknowledgement………………………………………………………………………xiv Abstract…………………………………………………………………………………xvi Chapter 1. Introduction 1.1 Conjugated Organic Materials: General Introduction …………….………1 1.2 Mutiple (pπ-pπ ) Bonding in Main Group Elements: Brief Historical Background………………………………………………………………..3
    [Show full text]
  • Throughconjugation of Two Phosphaalkyne ('CP') Moieties
    Through-conjugation of two phosphaalkyne (`CP') moieties mediated by a bimetallic scaffold² Article (Published Version) Leech, Matthew C and Crossley, Ian R (2018) Through-conjugation of two phosphaalkyne (‘CP’) moieties mediated by a bimetallic scaffold†. Dalton Transactions, 47. pp. 4428-4432. ISSN 1477- 9226 This version is available from Sussex Research Online: http://sro.sussex.ac.uk/id/eprint/74320/ This document is made available in accordance with publisher policies and may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher’s version. Please see the URL above for details on accessing the published version. Copyright and reuse: Sussex Research Online is a digital repository of the research output of the University. Copyright and all moral rights to the version of the paper presented here belong to the individual author(s) and/or other copyright owners. To the extent reasonable and practicable, the material made available in SRO has been checked for eligibility before being made available. Copies of full text items generally can be reproduced, displayed or performed and given to third parties in any format or medium for personal research or study, educational, or not-for-profit purposes without prior permission or charge, provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way. http://sro.sussex.ac.uk Dalton Transactions View Article Online COMMUNICATION View Journal | View Issue Through-conjugation of two phosphaalkyne (‘CuP’) moieties mediated by a bimetallic Cite this: Dalton Trans., 2018, 47, 4428 scaffold † Received 10th January 2018, Accepted 6th February 2018 Matthew.
    [Show full text]
  • Simple Access to Ionic Liquids and Organic Salts Containing the Phosphaethynolate (PCO) and Cite This: Chem
    ChemComm View Article Online COMMUNICATION View Journal | View Issue Simple access to ionic liquids and organic salts containing the phosphaethynolate (PCOÀ) and Cite this: Chem. Commun., 2016, 3À 52, 11646 Zintl (Sb11 ) anions† Received 11th August 2016, Accepted 20th August 2016 Maximilian Jost, Lars H. Finger, Jo¨rg Sundermeyer* and Carsten von Ha¨nisch* DOI: 10.1039/c6cc06620h www.rsc.org/chemcomm Herein we report the synthesis of the first ionic liquids with the unsubstituted or N-functionalised inorganic urea analogues,12,13 highly reactive and synthetically valuable phosphaethynolate (PCOÀ) andactsasaphosphidetransferreagent.14,15 anion. They are simply synthesised by the reaction of organic The most common route to the PCOÀ anion starts from methylcarbonate salts with P(SiMe3)3. The products are obtained in NaPH2, which is converted under CO pressure or with ethylene- 12 Creative Commons Attribution-NonCommercial 3.0 Unported Licence. near to quantitative yields and they are highly viscous liquids at room carbonate in dimethoxyethane. As the number of ionic synthons temperature or have low melting points for symmetric cations. for PCOÀ was limited to very few inorganic cations our interest Moreover, extending this synthetic strategy towards Sb(SiMe3)3 we was focused on developing a convenient preparation method for + 3À discovered a simple synthesis for [P(nBu)3Me] 3[Sb11] , the first new organic salts containing this anion. It should be mentioned 3À organic cation salt comprising the Zintl-anion [Sb11] . that simple ion exchange in water/methylene chloride or chloro- form typically used in ionic liquid syntheses does not lead to this The first synthesis of the PCOÀ anion goes back to the early class of reactive organic PCO salts in the pure state.
    [Show full text]
  • Group Multiple Bonds for Bond Activations and Catalysis Catherine Weetman*[A]
    Minireview Chemistry—A European Journal doi.org/10.1002/chem.202002939 & Main Group Elements |Reviews Showcase| Main Group Multiple Bonds for Bond Activations and Catalysis Catherine Weetman*[a] Chem. Eur. J. 2020, 26,1–15 1 2020 The Authors. Published by Wiley-VCH GmbH && These are not the final page numbers! ÞÞ Minireview Chemistry—A European Journal doi.org/10.1002/chem.202002939 Abstract: Since the discovery that the so-called “double- thermore, whilst their ability to act as transition metal bond” rule could be broken, the field of molecular main mimics has been explored, their catalytic behaviour is some- group multiple bonds has expanded rapidly. With the major- what limited. This Minireview aims to highlight the potential ity of homodiatomic double and triple bonds realised within of these complexes towards catalytic application and their the p-block, along with many heterodiatomic combinations, role as synthons in further functionalisations making them a this Minireview examines the reactivity of these compounds versatile tool for the modern synthetic chemist. with a particular emphasis on small molecule activation. Fur- Introduction On descending the group the stability of the lower oxidation state increases and thus its desire to partake in bond forma- Molecular main group multiple bond chemistry has rapidly de- tion decreases. For example in group 14, SnII is more stable veloped since the isolation of the first silicon-silicon double than SnIV, whilst for the lightest congener CIV is more stable bond. West’s disilene[1] broke the so called “double-bond” rule, than CII. This can also influence the complex formation in both in which it was thought that p-block elements with a principal the solution and solid state as highlighted by Lappert’s quantum number greater than two (i.e.
    [Show full text]
  • L3C3P3: Tricarbontriphosphide Tricyclic Radicals and Cations
    Author Manuscript Title: L3C3P3: Tricarbontriphosphide Cage Radicals and Cations Stabilized by Cy- clic (alkyl)(amino)carbenes Authors: Hansjorg¨ Grutzmacher,¨ Prof.; Zhongshu Li; Yuanfeng Hou; Yaqi Li; Alexan- der Hinz; Jeffrey Harmer; Chen-Yong Su; Guy Bertrand This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofrea- ding process, which may lead to differences between this version and the Version of Record. To be cited as: 10.1002/ange.201710099 Link to VoR: https://doi.org/10.1002/ange.201710099 L3C3P3: Tricarbontriphosphide Cage Radicals and Cations Stabilized by Cyclic (alkyl)(amino)carbenes Zhongshu Li,[a] Yuanfeng Hou,[a] Yaqi Li,[a] Alexander Hinz,[b] Jeffrey R. Harmer,*[c] Cheng-Yong Su,[a] Guy Bertrand,[e] and Hansjörg Grützmacher*[a,d] [a] Dr. Z. Li, Y. Hou, Y. Li, Prof. Dr. C.-Y. Su, Lehn Institute of Functional Materials (LIFM) School of Chemistry Sun Yat-Sen University 510275 Guangzhou, China E-mail: [email protected] [b] Dr. A. Hinz University of Oxford, Chemistry Research Laboratory 12 Mansfield Road, OX1 3TA, Oxford, UK E-mail: [email protected] [c] Assoc. Prof. Dr. J. R. Harmer. Centre for Advanced Imaging, University of Queensland, Brisbane, QLD, 4072, Australia E-mail: [email protected] [d] Prof. Dr. H. Grützmacher Department of Chemistry and Applied Biosciences ETH Zurich 8093 Zurich, Switzerland E-mail: [email protected] [e] Prof. Dr. G. Bertrand UCSD/CNRS Joint Research Chemistry Laboratory Department of Chemistry University of California San Diego La Jolla, CA 92521–0403, USA E-mail: [email protected] 1 This article is protected by copyright.
    [Show full text]