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Pizzi A, Dhaka A, Beccaria R, Resnati G. Anion⋯anion self-assembly under the control of σ- and π-hole bonds. Chem Soc Rev 2024. [PMID: 38867604 DOI: 10.1039/d3cs00479a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
The electrostatic attraction between charges of opposite signs and the repulsion between charges of the same sign are ubiquitous and influential phenomena in recognition and self-assembly processes. However, it has been recently revealed that specific attractive forces between ions with the same sign are relatively common. These forces can be strong enough to overcome the Coulomb repulsion between ions with the same sign, leading to the formation of stable anion⋯anion and cation⋯cation adducts. Hydroden bonds (HBs) are probably the best-known interaction that can effectively direct these counterintuitive assembly processes. In this review we discuss how σ-hole and π-hole bonds can break the paradigm of electrostatic repulsion between like-charges and effectively drive the self-assembly of anions into discrete as well as one-, two-, or three-dimensional adducts. σ-Hole and π-hole bonds are the attractive forces between regions of excess electron density in molecular entities (e.g., lone pairs or π bond orbitals) and regions of depleted electron density that are localized at the outer surface of bonded atoms opposite to the σ covalent bonds formed by atoms (σ-holes) and above and below the planar portions of molecular entities (π-holes). σ- and π-holes can be present on many different elements of the p and d block of the periodic table and the self-assembly processes driven by their presence can thus involve a wide diversity of mono- and di-anions. The formed homomeric and heteromeric adducts are typically stable in the solid phase and in polar solvents but metastable or unstable in the gas phase. The pivotal role of σ- and π-hole bonds in controlling anion⋯anion self-assembly is described in key biopharmacological systems and in molecular materials endowed with useful functional properties.
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Affiliation(s)
- Andrea Pizzi
- NFMLab, Department of Chemistry, Materials, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, I-20131 Milano, Italy.
| | - Arun Dhaka
- NFMLab, Department of Chemistry, Materials, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, I-20131 Milano, Italy.
| | - Roberta Beccaria
- NFMLab, Department of Chemistry, Materials, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, I-20131 Milano, Italy.
| | - Giuseppe Resnati
- NFMLab, Department of Chemistry, Materials, Chemical Engineering "Giulio Natta", Politecnico di Milano, via Mancinelli 7, I-20131 Milano, Italy.
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2
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Varadwaj PR. Halogen Bond via an Electrophilic π-Hole on Halogen in Molecules: Does It Exist? Int J Mol Sci 2024; 25:4587. [PMID: 38731806 PMCID: PMC11083155 DOI: 10.3390/ijms25094587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 03/31/2024] [Accepted: 04/07/2024] [Indexed: 05/13/2024] Open
Abstract
This study reveals a new non-covalent interaction called a π-hole halogen bond, which is directional and potentially non-linear compared to its sister analog (σ-hole halogen bond). A π-hole is shown here to be observed on the surface of halogen in halogenated molecules, which can be tempered to display the aptness to form a π-hole halogen bond with a series of electron density-rich sites (Lewis bases) hosted individually by 32 other partner molecules. The [MP2/aug-cc-pVTZ] level characteristics of the π-hole halogen bonds in 33 binary complexes obtained from the charge density approaches (quantum theory of intramolecular atoms, molecular electrostatic surface potential, independent gradient model (IGM-δginter)), intermolecular geometries and energies, and second-order hyperconjugative charge transfer analyses are discussed, which are similar to other non-covalent interactions. That a π-hole can be observed on halogen in halogenated molecules is substantiated by experimentally reported crystals documented in the Cambridge Crystal Structure Database. The importance of the π-hole halogen bond in the design and growth of chemical systems in synthetic chemistry, crystallography, and crystal engineering is yet to be fully explicated.
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Affiliation(s)
- Pradeep R. Varadwaj
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1, Tokyo 113-8656, Japan;
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg 2050, South Africa
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3
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Savastano M. Ye Olde supramolecular chemistry, its modern rebranding and overarching trends in chemistry. Dalton Trans 2024; 53:1373-1392. [PMID: 38180341 DOI: 10.1039/d3dt03686c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
We can describe current contingency of supramolecular chemistry as "post-halogen bonding", with clear reference to the success of the σ-hole model and the halogen bond concepts. This phase is characterized by a strong push towards a new nomenclature for non-covalent interactions, a group-by-group one focusing on the electrophile. As such nomenclature increasingly meets IUPAC endorsement, its proposers report resistances to such ideas, especially in the inorganic and coordination chemistry communities. The whole issue has been generating considerable debate in the last decade. Herein we fully embrace such discussion in the hope of involving a larger share of the relevant communities. Alternative descriptions are here reevaluated, novel views reconnected with older ones, and it is ultimately questioned whether the introduction of such a nomenclature and its subtending ideas would be beneficial. The themes of appreciation of general trends in chemistry, of counterintuitive interactions, of positioning of novel nomenclature with respect to existing ones, and of the extension of group-by-group naming from main block to d-block elements - as key and currently unresolved issues - are discussed. Equivalent, alternative and arguably more comprehensive descriptions are tentatively given, in the hope to overcome controversies together in the pursuit of higher rewards: a comprehensive shared view of supramolecular forces and a common language to express it.
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Affiliation(s)
- Matteo Savastano
- Department of Human Sciences for the Promotion of Quality of Life, University San Raffaele Roma, via di Val Cannuta 247, 00166, Rome, Italy.
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4
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Martín-Fernández C, Ferrer M, Alkorta I, Montero-Campillo MM, Elguero J, Mandado M. Metastable Charged Dimers in Organometallic Species: A Look into Hydrogen Bonding between Metallocene Derivatives. Inorg Chem 2023; 62:16523-16537. [PMID: 37755334 DOI: 10.1021/acs.inorgchem.3c02355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
Multiply charged complexes bound by noncovalent interactions have been previously described in the literature, although they were mostly focused on organic and main group inorganic systems. In this work, we show that similar complexes can also be found for organometallic systems containing transition metals and deepen in the reasons behind the existence of these species. We have studied the structures, binding energies, and dissociation profiles in the gas phase of a series of charged hydrogen-bonded dimers of metallocene (Ru, Co, Rh, and Mn) derivatives isoelectronic with the ferrocene dimer. Our results indicate that the carboxylic acid-containing dimers are more strongly bonded and present larger barriers to dissociation than the amide ones and that the cationic complexes tend to be more stable than the anionic ones. Additionally, we describe for the first time the symmetric proton transfer that can occur while in the metastable phase. Finally, we use a density-based energy decomposition analysis to shine light on the nature of the interaction between the dimers.
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Affiliation(s)
| | - Maxime Ferrer
- Instituto de Química Médica (CSIC), Juan de la Cierva, 3, 28006 Madrid, Spain
- PhD Programme in Theoretical Chemistry and Computational Modelling, Doctoral School, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Ibon Alkorta
- Instituto de Química Médica (CSIC), Juan de la Cierva, 3, 28006 Madrid, Spain
| | - M Merced Montero-Campillo
- Departamento de Química (Módulo 13, Facultad de Ciencias), Campus de Excelencia UAM-CSIC, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - José Elguero
- Instituto de Química Médica (CSIC), Juan de la Cierva, 3, 28006 Madrid, Spain
| | - Marcos Mandado
- Departamento de Química Física, Universidade de Vigo, Lagoas-Marcosende s/n, 36310 Vigo, Spain
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5
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An S, Hao A, Xing P. Supramolecular axial chirality in [N-I-N] +-type halogen bonded dimers. Chem Sci 2023; 14:10194-10202. [PMID: 37772111 PMCID: PMC10530288 DOI: 10.1039/d3sc03170e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 08/25/2023] [Indexed: 09/30/2023] Open
Abstract
Axial chiral molecules are extensively used as skeletons in ligands for asymmetric catalysis and as building blocks of chiroptical materials. Designing axial chirality at the supramolecular level potentially endows a material with dynamic tunability and adaptivity. In this work, for the first time, we have reported a series of halogen-bonded dimeric complexes with axial chirality that were formed by noncovalent bonds. The [N-I-N]+-type halogen bond is highly directional and freely rotatable with good linearity and ultra-high bond energy; this bond was introduced to couple quinoline moieties with chiral substitutes. The resultant dimers were stable in solutions with thermo-resistance. Prominent steric effects from the 2' chiral pendant allowed the chirality to be transferred to aryl skeletons with induced preferred axial chirality and optical activities. Halogen-bonded complexation presented visible emissions to afford luminescent axial chiral materials, whereby circularly polarized fluorescence and phosphorescence were achieved. The [N-I-N]+-type halogen bond performed as a powerful tool to construct functional axial chiral compounds, enriching the toolbox for asymmetric synthesis and optics.
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Affiliation(s)
- Shuguo An
- Key Laboratory of Colloid and Interface Chemistry of Ministry of Education and School of Chemistry and Chemical Engineering, Shandong University Jinan 250100 People's Republic of China
| | - Aiyou Hao
- Key Laboratory of Colloid and Interface Chemistry of Ministry of Education and School of Chemistry and Chemical Engineering, Shandong University Jinan 250100 People's Republic of China
| | - Pengyao Xing
- Key Laboratory of Colloid and Interface Chemistry of Ministry of Education and School of Chemistry and Chemical Engineering, Shandong University Jinan 250100 People's Republic of China
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An S, Hao A, Xing P. [N···I···N] + Type Halogen-Bonding-Driven Supramolecular Helical Polymers with Modulated Chirality. ACS NANO 2022; 16:19220-19228. [PMID: 36286252 DOI: 10.1021/acsnano.2c08506] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The [N···I···N]+ type halogen bond has been utilized to synthesize supramolecular architectures, while the applications in constructing helical motifs and modulating supramolecular chirality have been unexplored so far. In this work, the [N···I···N]+ halogen bond was introduced to drive the formation of supramolecular helical polymers via a Ag(I) coordination intermediate, showing tunable supramolecular chirality. Pyridine segments were conjugated to the asymmetric ferrocene skeleton, which show "open" and "closed" geometry depending on the sp2 N positions. Coordination with Ag(I) generated one-dimensional (1D) double helices and 2D helicates featured the [Ag(O)···I···Ag(O)]+ bond, which further stacked into 3D porous frameworks with chiral channels and adjustable pore sizes. Ionic exchange afforded 1D supramolecular helical polymers in solution phases driven by the [N···I···N]+ type halogen bonds, which was evidenced by the experimental results and density functional theory calculation. Fc2 exclusively demonstrated tunable supramolecular chirality in the formation of coordinated and halogen bonded polymers. In addition, solvent change would further inverse the helicity of halogen bonded supramolecular helical polymers depending on the rotation of the ferrocenyl core whose "closed" and "open" states were accompanied by the breakage of intramolecular hydrogen bonds. This work introduces a [N···I···N]+ type ionic halogen bond to prepare supramolecular helical polymers, providing multiple protocols in regulating helicity by ion exchange and solvent environments.
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Affiliation(s)
- Shuguo An
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Aiyou Hao
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Pengyao Xing
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
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7
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Definition of the Pnictogen Bond: A Perspective. INORGANICS 2022. [DOI: 10.3390/inorganics10100149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
This article proposes a definition for the term “pnictogen bond” and lists its donors, acceptors, and characteristic features. These may be invoked to identify this specific subset of the inter- and intramolecular interactions formed by elements of Group 15 which possess an electrophilic site in a molecular entity.
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8
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Scheiner S. On the reliability of atoms in molecules, noncovalent index, and natural bond orbital to identify and quantify noncovalent bonds. J Comput Chem 2022; 43:1814-1824. [DOI: 10.1002/jcc.26983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/03/2022] [Indexed: 11/12/2022]
Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry Utah State University Logan Utah USA
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9
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Zhang Y, Wang W. Origin of the unexpected attractive interactions between positive σ-holes and positive π-lumps. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2022.113736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Harry SA, Vemulapalli S, Dudding T, Lectka T. Rational Computational Design of Systems Exhibiting Strong Halogen Bonding Involving Fluorine in Bicyclic Diamine Derivatives. J Org Chem 2022; 87:8413-8419. [PMID: 35658438 DOI: 10.1021/acs.joc.2c00497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Perhaps the most controversial and rare aspect of the halogen bonding interaction is the potential of fluorine in compounds to serve as a halogen bond donor. In this note, we provide clear and convincing examples of hypothetical molecules in which fluorine is strongly halogen bonding in a metastable state. Of particular note is a polycyclic system inspired by Selectfluor, which has been controversially proposed to engage in halogen bonding.
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Affiliation(s)
- Stefan Andrew Harry
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Srini Vemulapalli
- Department of Chemistry, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Travis Dudding
- Department of Chemistry, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Thomas Lectka
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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11
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The Role of Hydrogen Bonds in Interactions between [PdCl 4] 2- Dianions in Crystal. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27072144. [PMID: 35408543 PMCID: PMC9000617 DOI: 10.3390/molecules27072144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/18/2022] [Accepted: 03/22/2022] [Indexed: 11/17/2022]
Abstract
[PdCl4]2- dianions are oriented within a crystal in such a way that a Cl of one unit approaches the Pd of another from directly above. Quantum calculations find this interaction to be highly repulsive with a large positive interaction energy. The placement of neutral ligands in their vicinity reduces the repulsion, but the interaction remains highly endothermic. When the ligands acquire a unit positive charge, the electrostatic component and the full interaction energy become quite negative, signalling an exothermic association. Raising the charge on these counterions to +2 has little further stabilizing effect, and in fact reduces the electrostatic attraction. The ability of the counterions to promote the interaction is attributed in part to the H-bonds which they form with both dianions, acting as a sort of glue.
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12
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Weinhold F. Anti-Electrostatic Pi-Hole Bonding: How Covalency Conquers Coulombics. Molecules 2022; 27:377. [PMID: 35056689 PMCID: PMC8780338 DOI: 10.3390/molecules27020377] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 12/30/2021] [Accepted: 12/30/2021] [Indexed: 12/20/2022] Open
Abstract
Intermolecular bonding attraction at π-bonded centers is often described as "electrostatically driven" and given quasi-classical rationalization in terms of a "pi hole" depletion region in the electrostatic potential. However, we demonstrate here that such bonding attraction also occurs between closed-shell ions of like charge, thereby yielding locally stable complexes that sharply violate classical electrostatic expectations. Standard DFT and MP2 computational methods are employed to investigate complexation of simple pi-bonded diatomic anions (BO-, CN-) with simple atomic anions (H-, F-) or with one another. Such "anti-electrostatic" anion-anion attractions are shown to lead to robust metastable binding wells (ranging up to 20-30 kcal/mol at DFT level, or still deeper at dynamically correlated MP2 level) that are shielded by broad predissociation barriers (ranging up to 1.5 Å width) from long-range ionic dissociation. Like-charge attraction at pi-centers thereby provides additional evidence for the dominance of 3-center/4-electron (3c/4e) nD-π*AX interactions that are fully analogous to the nD-σ*AH interactions of H-bonding. Using standard keyword options of natural bond orbital (NBO) analysis, we demonstrate that both n-σ* (sigma hole) and n-π* (pi hole) interactions represent simple variants of the essential resonance-type donor-acceptor (Bürgi-Dunitz-type) attraction that apparently underlies all intermolecular association phenomena of chemical interest. We further demonstrate that "deletion" of such π*-based donor-acceptor interaction obliterates the characteristic Bürgi-Dunitz signatures of pi-hole interactions, thereby establishing the unique cause/effect relationship to short-range covalency ("charge transfer") rather than envisioned Coulombic properties of unperturbed monomers.
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Affiliation(s)
- Frank Weinhold
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53705, USA
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13
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Abstract
A halogen-bonded complex containing a pair of anions can be made more stable than the isolated anions if the Lewis acid is a long carbon chain, fully substituted by CN groups, with an I atom on one end and a COO− group on the other, with Cl− as base.
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Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, USA
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14
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Shi R, Yu D, Zhou F, Yu J, Mu T. An emerging deep eutectic solvent based on halogen-bond. Chem Commun (Camb) 2022; 58:4607-4610. [DOI: 10.1039/d2cc00528j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new deep eutectic solvents (DES) driven by halogen-bond was exploited. A family of eutectic mixtures in liquid state were obtained by combination of quaternary ammonium salts and dihalogens. The...
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15
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Chen L, Feng Q, Wang C, Yin S, Mo Y. Classical Electrostatics Remains the Driving Force for Interanion Hydrogen and Halogen Bonding. J Phys Chem A 2021; 125:10428-10438. [PMID: 34818021 DOI: 10.1021/acs.jpca.1c09250] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Interanion hydrogen bonding (IAHB) and halogen bonding (IAXB) have emerged as a counterintuitive linker in a range of fascinating applications. Despite the overall repulsive (positive) binding energy, anions are trapped in a local minimum with its corresponding transition state (TS) preventing dissociation. In other words, the adduct of anions is metastable. Seemingly, the electrostatic paradigm and force field description of hydrogen/halogen bonding (HB/XB) are challenged, because of the preconceived Coulombic repulsion. Aiming at an insightful understanding of these interanion phenomena, we employed the energy decomposition approach based on the block-localized wavefunction method (BLW-ED) to investigate a series of exemplary interanion complexes. As expected, the key distinction from the conventional HB/XB lies in the electrostatic interaction, which is not increasingly repulsive as anions gradually approach to each other. Rather, there is a Coulombic barrier at a certain point. After this point, the electrostatic repulsion diminishes with the decreasing distance between anions. Differently, other energy components vary monotonically just like in conventional cases. The nonmonotonic characteristic of the electrostatic interaction in interanion complexes was reproduced using the multipole expansion in AMOEBA polarizable force field in which the state-specified atomic multipoles were adopted. This suggests that the nonmonotonicity can be well interpreted by classical electrostatic theory and there is no conceptual difference between conventional HB/XB and IAHB/IAXB. The stability of IAHB/IAXB depends on the competition between the local attractive HB/XB and the global Coulombic repulsion of net charges, though there is cooperativity between these two contrasting forces. This concise model was supported by the attractive IAHB/IAXB in modified molecular capsules, which exhibit strong quadruple HB/XBs and a considerable distance between charged substituents.
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Affiliation(s)
- Li Chen
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Qiuyan Feng
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Changwei Wang
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Shiwei Yin
- Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, China
| | - Yirong Mo
- Department of Nanoscience, Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, North Carolina 27401, United States
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Tarannam N, Shukla R, Kozuch S. Yet another perspective on hole interactions. Phys Chem Chem Phys 2021; 23:19948-19963. [PMID: 34514473 DOI: 10.1039/d1cp03533a] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Hole interactions are known by different names depending on the key atom of the bond (halogen bond, chalcogen bond, hydrogen bond, etc.), and the geometry of the interaction (σ if in line, π if perpendicular to the Lewis acid plane). However, its origin starts with the creation of a Lewis acid by an underlying covalent bond, which forms an electrostatic depletion and a virtual antibonding orbital, which can create non-covalent interactions with Lewis bases. In this (maybe subjective) perspective, we will claim that hole interactions must be defined via the molecular orbital origin of the molecule. Under this premise we can better explore the richness of such bonding patterns. For that, we will study old, recent and new systems, trying to pinpoint some misinterpretations that are often associated with them. We will use as exemplars the triel bonds, a couple of metal complexes, a discussion on convergent σ-holes, and many cases of anti-electrostatic hole interactions.
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Affiliation(s)
- Naziha Tarannam
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 841051, Israel.
| | - Rahul Shukla
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 841051, Israel.
| | - Sebastian Kozuch
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 841051, Israel.
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