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Beer H, Siewert JE, Schröder M, Fischer M, Corzilius B, Hering-Junghans C. Phosphaarsenes - Combining Phospha- and Arsa-Wittig-Reagents. Chempluschem 2024; 89:e202400120. [PMID: 38488262 DOI: 10.1002/cplu.202400120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/12/2024] [Indexed: 04/14/2024]
Abstract
Dipnictenes of the type RPn=PnR (Pn=P, As, Sb, Bi) can be viewed as dimers of the corresponding pnictinidenes R-Pn. Phosphanylidene- and arsanylidenephosphoranes (R-Pn(PMe3); Pn=P, As) have been shown to be versatile synthetic surrogates for the delivery of pnictinidene fragments. We now report that thermal treatment of 1 : 1 mixtures of R-P(PMe3) and R'-As(PMe3) gives access to arsaphosphenes of the type RP=AsR'. Three examples are presented and the properties and reactivity of Mes*P=AsDipTer (1) (Mes*=2,4,6-tBu3-C6H2; DipTer=2,6-(2,6-iPr2C6H3)2-C6H3) were studied in detail. Solid state 31P NMR spectroscopy revealed a large 31P NMR chemical shift anisotropy with a span of ca. 920 ppm for 1 while computational methods were employed to investigate this pronounced magnetic deshielding of the P atom in 1. In the presence of the carbene IMe4 (IMe4=:C(MeNCMe)2) 1 is shown to be split into the corresponding NHC adducts Mes*P(IMe4) and DipTerAs(IMe4), which is additionally shown for diarsenes.
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Affiliation(s)
- Henrik Beer
- Leibniz-Institut für Katalyse (LIKAT), Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Jan-Erik Siewert
- Leibniz-Institut für Katalyse (LIKAT), Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Mirjam Schröder
- Leibniz-Institut für Katalyse (LIKAT), Albert-Einstein-Straße 29a, 18059, Rostock, Germany
- Institut für Chemie und Department Life, Light & Matter, Universität Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
| | - Malte Fischer
- Leibniz-Institut für Katalyse (LIKAT), Albert-Einstein-Straße 29a, 18059, Rostock, Germany
- Georg-August-Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, 37077, Göttingen, Germany
| | - Björn Corzilius
- Leibniz-Institut für Katalyse (LIKAT), Albert-Einstein-Straße 29a, 18059, Rostock, Germany
- Institut für Chemie und Department Life, Light & Matter, Universität Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
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2
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Breitwieser K, Bevilacqua M, Mullassery S, Dankert F, Morgenstern B, Grandthyll S, Müller F, Biffis A, Hering‐Junghans C, Munz D. Pd 8(PDip) 6: Cubic, Unsaturated, Zerovalent. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2400699. [PMID: 38634573 PMCID: PMC11220702 DOI: 10.1002/advs.202400699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/22/2024] [Indexed: 04/19/2024]
Abstract
Atomically precise nanoclusters hold promise for supramolecular assembly and (opto)electronic- as well as magnetic materials. Herein, this work reports that treating palladium(0) precursors with a triphosphirane affords strongly colored Pd8(PDip)6 that is fully characterized by mass spectrometry, heteronuclear and Cross-Polarization Magic-Angle Spinning (CP-MAS) NMR-, infrared (IR), UV-vis, and X-ray photoelectron (XP) spectroscopies, single-crystal X-Ray diffraction (sc-XRD), mass spectrometry, and cyclovoltammetry (CV). This coordinatively unsaturated 104-electron Pd(0) cluster features a cubic Pd8-core, µ4-capping phosphinidene ligands, and is air-stable. Quantum chemical calculations provide insight to the cluster's electronic structure and suggest 5s/4d orbital mixing as well as minor Pd─P covalency. Trapping experiments reveal that cluster growth proceeds via insertion of Pd(0) into the triphosphirane. The unsaturated cluster senses ethylene and binds isocyanides, which triggers the rearrangement to a tetrahedral structure with a reduced frontier orbital energy gap. These experiments demonstrate facile cluster manipulation and highlight non-destructive cluster rearrangement as is required for supramolecular assembly.
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Affiliation(s)
- Kevin Breitwieser
- Coordination Chemistry Saarland UniversityCampus C4.1D‐66123SaarbrückenGermany
| | - Matteo Bevilacqua
- Coordination Chemistry Saarland UniversityCampus C4.1D‐66123SaarbrückenGermany
- Dipartimento di Scienze ChimicheUniversità degli Studi di Padovavia Marzolo 1PadovaI‐35131Italy
| | - Sneha Mullassery
- Coordination Chemistry Saarland UniversityCampus C4.1D‐66123SaarbrückenGermany
| | - Fabian Dankert
- Coordination Chemistry Saarland UniversityCampus C4.1D‐66123SaarbrückenGermany
| | - Bernd Morgenstern
- Coordination Chemistry Saarland UniversityCampus C4.1D‐66123SaarbrückenGermany
| | - Samuel Grandthyll
- Experimental Physics and Center for BiophysicsSaarland UniversityCampus E2.9D‐66123SaarbrückenGermany
| | - Frank Müller
- Experimental Physics and Center for BiophysicsSaarland UniversityCampus E2.9D‐66123SaarbrückenGermany
| | - Andrea Biffis
- Dipartimento di Scienze ChimicheUniversità degli Studi di Padovavia Marzolo 1PadovaI‐35131Italy
| | - Christian Hering‐Junghans
- Katalyse mit phosphorhaltigen MaterialienLeibniz Institut für Katalyse e.VAlbert‐Einstein‐Straße 29aD‐18059RostockGermany
| | - Dominik Munz
- Coordination Chemistry Saarland UniversityCampus C4.1D‐66123SaarbrückenGermany
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3
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Hales DP, Rajeshkumar T, Shiau AA, Rao G, Ouellette ET, Bergman RG, Britt RD, Maron L, Arnold J. Panoply of P: An Array of Rhenium-Phosphorus Complexes Generated from a Transition Metal Anion. Inorg Chem 2024; 63:11296-11310. [PMID: 38836624 DOI: 10.1021/acs.inorgchem.4c01085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
We expand upon the synthetic utility of anionic rhenium complex Na[(BDI)ReCp] (1, BDI = N,N'-bis(2,6-diisopropylphenyl)-3,5-dimethyl-β-diketiminate) to generate several rhenium-phosphorus complexes. Complex 1 reacts in a metathetical manner with chlorophosphines Ph2PCl, MeNHP-Cl, and OHP-Cl to generate XL-type phosphido complexes 2, 3, and 4, respectively (MeNHP-Cl = 2-chloro-1,3-dimethyl-1,3,2-diazaphospholidine; OHP-Cl = 2-chloro-1,3,2-dioxaphospholane). Crystallographic and computational investigations of phosphido triad 2, 3, and 4 reveal that increasing the electronegativity of the phosphorus substituent (C < N < O) results in a shortening and strengthening of the rhenium-phosphorus bond. Complex 1 reacts with iminophosphane Mes*NPCl (Mes* = 2,4,6-tritert-butylphenyl) to generate linear iminophosphanyl complex 5. In the presence of a suitable halide abstraction reagent, 1 reacts with the dichlorophosphine iPr2NPCl2 to afford cationic phosphinidene complex 6+. Complex 6+ may be reduced by one electron to form 6•, a rare example of a stable, paramagnetic phosphinidene complex. Spectroscopic and structural investigations, as well as computational analyses, are employed to elucidate the influence of the phosphorus substituent on the nature of the rhenium-phosphorus bond in 2 through 6. Furthermore, we examine several common analogies employed to understand metal phosphido, phosphinidene, and iminophosphanyl complexes.
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Affiliation(s)
- David P Hales
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Thayalan Rajeshkumar
- LPCNO, INSA Toulouse, Université de Toulouse, 135 Avenue de Rangueil, Toulouse 31077, France
| | - Angela A Shiau
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Guodong Rao
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Erik T Ouellette
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Robert G Bergman
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - R David Britt
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Laurent Maron
- LPCNO, INSA Toulouse, Université de Toulouse, 135 Avenue de Rangueil, Toulouse 31077, France
| | - John Arnold
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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4
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He M, Hu C, Wei R, Wang XF, Liu LL. Recent advances in the chemistry of isolable carbene analogues with group 13-15 elements. Chem Soc Rev 2024; 53:3896-3951. [PMID: 38436383 DOI: 10.1039/d3cs00784g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2024]
Abstract
Carbenes (R2C:), compounds with a divalent carbon atom containing only six valence shell electrons, have evolved into a broader class with the replacement of the carbene carbon or the RC moiety with main group elements, leading to the creation of main group carbene analogues. These analogues, mirroring the electronic structure of carbenes (a lone pair of electrons and an empty orbital), demonstrate unique reactivity. Over the last three decades, this area has seen substantial advancements, paralleling the innovations in carbene chemistry. Recent studies have revealed a spectrum of unique carbene analogues, such as monocoordinate aluminylenes, nitrenes, and bismuthinidenes, notable for their extraordinary properties and diverse reactivity, offering promising applications in small molecule activation. This review delves into the isolable main group carbene analogues that are in the forefront from 2010 and beyond, spanning elements from group 13 (B, Al, Ga, In, and Tl), group 14 (Si, Ge, Sn, and Pb) and group 15 (N, P, As, Sb, and Bi). Specifically, this review focuses on the potential amphiphilic species that possess both lone pairs of electrons and vacant orbitals. We detail their comprehensive synthesis and stabilization strategies, outlining the reactivity arising from their distinct structural characteristics.
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Affiliation(s)
- Mian He
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Chaopeng Hu
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Rui Wei
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Xin-Feng Wang
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Liu Leo Liu
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
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5
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Gui X, Sorbelli D, Caló FP, Leutzsch M, Patzer M, Fürstner A, Bistoni G, Auer AA. Elucidating the Electronic Nature of Rh-based Paddlewheel Catalysts from 103 Rh NMR Chemical Shifts: Insights from Quantum Mechanical Calculations. Chemistry 2024; 30:e202301846. [PMID: 37721802 DOI: 10.1002/chem.202301846] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 09/18/2023] [Accepted: 09/18/2023] [Indexed: 09/20/2023]
Abstract
The tremendous importance of dirhodium paddlewheel complexes for asymmetric catalysis is largely the result of an empirical optimization of the chiral ligand sphere about the bimetallic core. It was only recently that a H(C)Rh triple resonance 103 Rh NMR experiment provided the long-awaited opportunity to examine - with previously inconceivable accuracy - how variation of the ligands impacts on the electronic structure of such catalysts. The recorded effects are dramatic: formal replacement of only one out of eight O-atoms surrounding the metal centers in a dirhodium tetracarboxylate by an N-atom results in a shielding of the corresponding Rh-site of no less than 1000 ppm. The current paper provides the theoretical framework that allows this and related experimental observations made with a set of 19 representative rhodium complexes to be interpreted. In line with symmetry considerations, it is shown that the shielding tensor responds only to the donor ability of the equatorial ligands along the perpendicular principal axis. Axial ligands, in contrast, have no direct effect on shielding but may come into play via the electronicc i s ${cis}$ -effect that they exert onto the neighboring equatorial sites. On top of these fundamental interactions, charge redistribution within the core as well as the electronict r a n s ${trans}$ -effect of ligands of different donor strengths is reflected in the recorded 103 Rh NMR shifts.
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Affiliation(s)
- Xin Gui
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
| | - Diego Sorbelli
- Dipartmento di Chimica, Biologia e Biotechnologie, Università Degli Studi Di Perugia, 06123, Perugia, Italy
| | - Fabio P Caló
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
| | - Markus Leutzsch
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
| | - Michael Patzer
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
| | - Giovanni Bistoni
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
- Dipartmento di Chimica, Biologia e Biotechnologie, Università Degli Studi Di Perugia, 06123, Perugia, Italy
| | - Alexander A Auer
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
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6
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Baker CF, Seed JA, Adams RW, Lee D, Liddle ST. 13C carbene nuclear magnetic resonance chemical shift analysis confirms Ce IV[double bond, length as m-dash]C double bonding in cerium(iv)-diphosphonioalkylidene complexes. Chem Sci 2023; 15:238-249. [PMID: 38131084 PMCID: PMC10732143 DOI: 10.1039/d3sc04449a] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023] Open
Abstract
Diphosphonioalkylidene dianions have emerged as highly effective ligands for lanthanide and actinide ions, and the resulting formal metal-carbon double bonds have challenged and developed conventional thinking about f-element bond multiplicity and covalency. However, f-element-diphosphonioalkylidene complexes can be represented by several resonance forms that render their metal-carbon double bond status unclear. Here, we report an experimentally-validated 13C Nuclear Magnetic Resonance computational assessment of two cerium(iv)-diphosphonioalkylidene complexes, [Ce(BIPMTMS)(ODipp)2] (1, BIPMTMS = {C(PPh2NSiMe3)2}2-; Dipp = 2,6-diisopropylphenyl) and [Ce(BIPMTMS)2] (2). Decomposing the experimental alkylidene chemical shifts into their corresponding calculated shielding (σ) tensor components verifies that these complexes exhibit Ce[double bond, length as m-dash]C double bonds. Strong magnetic coupling of Ce[double bond, length as m-dash]C σ/π* and π/σ* orbitals produces strongly deshielded σ11 values, a characteristic hallmark of alkylidenes, and the largest 13C chemical shift tensor spans of any alkylidene complex to date (1, 801 ppm; 2, 810 ppm). In contrast, the phosphonium-substituent shielding contributions are much smaller than the Ce[double bond, length as m-dash]C σ- and π-bond components. This study confirms significant Ce 4f-orbital contributions to the Ce[double bond, length as m-dash]C bonding, provides further support for a previously proposed inverse-trans-influence in 2, and reveals variance in the 4f spin-orbit contributions that relate to the alkylidene hybridisation. This work thus confirms the metal-carbon double bond credentials of f-element-diphosphonioalkylidenes, providing quantified benchmarks for understanding diphosphonioalkylidene bonding generally.
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Affiliation(s)
- Cameron F Baker
- Department of Chemistry, The University of Manchester Oxford Road Manchester M13 9PL UK
| | - John A Seed
- Department of Chemistry, The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Ralph W Adams
- Department of Chemistry, The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Daniel Lee
- Department of Chemical Engineering, The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Stephen T Liddle
- Department of Chemistry, The University of Manchester Oxford Road Manchester M13 9PL UK
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7
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Du J, Hurd J, Seed JA, Balázs G, Scheer M, Adams RW, Lee D, Liddle ST. 31P Nuclear Magnetic Resonance Spectroscopy as a Probe of Thorium-Phosphorus Bond Covalency: Correlating Phosphorus Chemical Shift to Metal-Phosphorus Bond Order. J Am Chem Soc 2023; 145:21766-21784. [PMID: 37768555 PMCID: PMC10571089 DOI: 10.1021/jacs.3c02775] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Indexed: 09/29/2023]
Abstract
We report the use of solution and solid-state 31P Nuclear Magnetic Resonance (NMR) spectroscopy combined with Density Functional Theory calculations to benchmark the covalency of actinide-phosphorus bonds, thus introducing 31P NMR spectroscopy to the investigation of molecular f-element chemical bond covalency. The 31P NMR data for [Th(PH2)(TrenTIPS)] (1, TrenTIPS = {N(CH2CH2NSiPri3)3}3-), [Th(PH)(TrenTIPS)][Na(12C4)2] (2, 12C4 = 12-crown-4 ether), [{Th(TrenTIPS)}2(μ-PH)] (3), and [{Th(TrenTIPS)}2(μ-P)][Na(12C4)2] (4) demonstrate a chemical shift anisotropy (CSA) ordering of (μ-P)3- > (═PH)2- > (μ-PH)2- > (-PH2)1- and for 4 the largest CSA for any bridging phosphido unit. The B3LYP functional with 50% Hartree-Fock mixing produced spin-orbit δiso values that closely match the experimental data, providing experimentally benchmarked quantification of the nature and extent of covalency in the Th-P linkages in 1-4 via Natural Bond Orbital and Natural Localized Molecular Orbital analyses. Shielding analysis revealed that the 31P δiso values are essentially only due to the nature of the Th-P bonds in 1-4, with largely invariant diamagnetic but variable paramagnetic and spin-orbit shieldings that reflect the Th-P bond multiplicities and s-orbital mediated transmission of spin-orbit effects from Th to P. This study has permitted correlation of Th-P δiso values to Mayer bond orders, revealing qualitative correlations generally, but which should be examined with respect to specific ancillary ligand families rather than generally to be quantitative, reflecting that 31P δiso values are a very sensitive reporter due to phosphorus being a soft donor that responds to the rest of the ligand field much more than stronger, harder donors like nitrogen.
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Affiliation(s)
- Jingzhen Du
- Department
of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Joseph Hurd
- Department
of Chemical Engineering, The University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - John A. Seed
- Department
of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Gábor Balázs
- Institute
of Inorganic Chemistry, University of Regensburg, Universitätsstr. 31, 93053 Regensburg, Germany
| | - Manfred Scheer
- Institute
of Inorganic Chemistry, University of Regensburg, Universitätsstr. 31, 93053 Regensburg, Germany
| | - Ralph W. Adams
- Department
of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Daniel Lee
- Department
of Chemical Engineering, The University
of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
| | - Stephen T. Liddle
- Department
of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, U.K.
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8
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Castro AC, Cascella M, Perutz RN, Raynaud C, Eisenstein O. Solid-State 19F NMR Chemical Shift in Square-Planar Nickel-Fluoride Complexes Linked by Halogen Bonds. Inorg Chem 2023; 62:4835-4846. [PMID: 36920236 PMCID: PMC10052355 DOI: 10.1021/acs.inorgchem.2c04063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Indexed: 03/16/2023]
Abstract
The halogen bond (XB) is a highly directional class of noncovalent interactions widely explored by experimental and computational studies. However, the NMR signature of the XB has attracted limited attention. The prediction and analysis of the solid-state NMR (SSNMR) chemical shift tensor provide useful strategies to better understand XB interactions. In this work, we employ a computational protocol for modeling and analyzing the 19F SSNMR chemical shifts previously measured in a family of square-planar trans NiII-L2-iodoaryl-fluoride (L = PEt3) complexes capable of forming self-complementary networks held by a NiF···I(C) halogen bond [Thangavadivale, V.; Chem. Sci. 2018, 9, 3767-3781]. To understand how the 19F NMR resonances of the nickel-bonded fluoride are affected by the XB, we investigate the origin of the shielding in trans-[NiF(2,3,5,6-C6F4I)(PEt3)2], trans-[NiF(2,3,4,5-C6F4I)(PEt3)2], and trans-[NiF(C6F5)(PEt3)2] in the solid state, where a XB is present in the two former systems but not in the last. We perform the 19F NMR chemical shift calculations both in periodic and molecular models. The results show that the crystal packing has little influence on the NMR signatures of the XB, and the NMR can be modeled successfully with a pair of molecules interacting via the XB. Thus, the observed difference in chemical shift between solid-state and solution NMR can be essentially attributed to the XB interaction. The very high shielding of the fluoride and its driving contributor, the most shielded component of the chemical shift tensor, are well reproduced at the 2c-ZORA level. Analysis of the factors controlling the shielding shows how the highest occupied Ni/F orbitals shield the fluoride in the directions perpendicular to the Ni-F bond and specifically perpendicular to the coordination plane. This shielding arises from the magnetic coupling of the Ni(3d)/F(2p lone pair) orbitals with the vacant σNi-F* orbital, thereby rationalizing the very highly upfield (shielded) resonance of the component (δ33) along this direction. We show that these features are characteristic of square-planar nickel-fluoride complexes. The deshielding of the fluoride in the halogen-bonded systems is attributed to an increase in the energy gap between the occupied and vacant orbitals that are mostly responsible for the paramagnetic terms, notably along the most shielded direction.
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Affiliation(s)
- Abril C. Castro
- Hylleraas
Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, 0315 Oslo, Norway
| | - Michele Cascella
- Hylleraas
Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, 0315 Oslo, Norway
| | - Robin N. Perutz
- Department
of Chemistry, University of York, Heslington, YO10 5DD York, United Kingdom
| | | | - Odile Eisenstein
- Hylleraas
Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, 0315 Oslo, Norway
- ICGM,
Université Montpellier, CNRS, ENSCM, 34090 Montpellier, France
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9
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Ströbele M, Oeckler O, Thelen M, Fink RF, Krishnamurthy A, Kroeker S, Meyer HJ. Pnictide-Capped Butterfly Cluster in the Crystal Structure of Nb 4PnX11 ( Pn = N, P; X = Cl, Br, I). Inorg Chem 2022; 61:17599-17608. [DOI: 10.1021/acs.inorgchem.2c02646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Markus Ströbele
- Section for Solid-State and Theoretical Inorganic Chemistry, Institute of Inorganic Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, D-72076Tübingen, Germany
| | - Oliver Oeckler
- Institute for Mineralogy, Crystallography and Materials Science; Faculty of Chemistry and Mineralogy, Leipzig University, Scharnhorststraße 20, 04275Leipzig, Germany
| | - Michael Thelen
- Institute of Physical and Theoretical Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, D-72076Tübingen, Germany
| | - Reinhold F. Fink
- Institute of Physical and Theoretical Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, D-72076Tübingen, Germany
| | - Arun Krishnamurthy
- Department of Chemistry, University of Manitoba, Winnipeg, ManitobaR3T 2N2, Canada
| | - Scott Kroeker
- Department of Chemistry, University of Manitoba, Winnipeg, ManitobaR3T 2N2, Canada
| | - Hans-Jürgen Meyer
- Section for Solid-State and Theoretical Inorganic Chemistry, Institute of Inorganic Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, D-72076Tübingen, Germany
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10
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Sigmund LM, Engels E, Richert N, Greb L. Calix[4]pyrrolato gallate: square planar-coordinated gallium( iii) and its metal–ligand cooperative reactivity with CO 2 and alcohols. Chem Sci 2022; 13:11215-11220. [PMID: 36320463 PMCID: PMC9516954 DOI: 10.1039/d2sc03054c] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 09/07/2022] [Indexed: 11/25/2022] Open
Abstract
Forcing a priori tetracoordinate atoms into planar configuration represents a promising concept for enhanced reactivity of p-block element-based systems. Herein, the synthesis, characterization, and reactivity of calix[4]pyrrolato gallates, constituting square planar-coordinated gallium(iii) atoms, are reported. Unusual structural constraint-induced Lewis acidity against neutral and anionic donors is disclosed by experiment and rationalized by computations. An energetically balanced dearomatization/rearomatization of a pyrrole unit enables fully reversible metal–ligand cooperative capture of CO2. While alcohols are found unreactive against the gallates, a rapid and selective OH-bond activation can be triggered upon protonation of the ligand. Secondary ligand–sphere modification adds a new avenue to structurally-constrained complexes that unites functional group tolerance with unconventional reactivity. Ideally square-planar coordinated gallium(iii) species is isolated and fully characterized. Spontaneous metal–ligand cooperative reactivity towards CO2 is observed, while OH-bond activation of alcohols can be triggered by protonation of the ligand.![]()
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Affiliation(s)
- Lukas M. Sigmund
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, Heidelberg 69120, Germany
| | - Eliane Engels
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, Heidelberg 69120, Germany
| | - Nick Richert
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, Heidelberg 69120, Germany
| | - Lutz Greb
- Freie Universität Berlin, Anorganische Chemie, Fabeckstraße 34-36, Berlin 14195, Germany
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Ruppert H, Sigmund LM, Greb L. Calix[4]pyrroles as ligands: recent progress with a focus on the emerging p-block element chemistry. Chem Commun (Camb) 2021; 57:11751-11763. [PMID: 34661225 DOI: 10.1039/d1cc05120b] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Calix[4]pyrroles are readily synthesized in one step from pyrroles and ketones. For several decades, these macrocycles have been exploited as powerful anion receptors or ligands for transition and rare-earth metals. In contrast, calix[4]pyrrolates as ligands for p-block elements were established only in 2018. The present feature article reviews these developments, together with the recent progress on s-, d-, and f-block element complexes of the calix[4]pyrroles. Particular focus is given on the calix[4]pyrrolato aluminate and the corresponding silane, both featuring square planar-coordinated p-block elements in their highest oxidation states. These unique "anti-van't-Hoff-Le-Bel" structures introduce valuable characteristics into main-group element chemistry, such as agostic interactions or ligand-to-metal charge transfer absorptions. The most vital reactivities are highlighted, which rely on properties ranging from amphoterism, redox-activity, and a small HOMO-LUMO gap up to the ability to provide a platform for additional external stimuli. Overall, these developments underscore the beneficial impact of structural constraint of p-block elements and element-ligand cooperativity to enhance the functionality of the most abundant elements in their native oxidation states.
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Affiliation(s)
- Heiko Ruppert
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
| | - Lukas M Sigmund
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
| | - Lutz Greb
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
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