1
|
Javaly N, McCormick TM, Stuart DR. A comparison of structure, bonding and non-covalent interactions of aryl halide and diarylhalonium halogen-bond donors. Beilstein J Org Chem 2024; 20:1428-1435. [PMID: 38952957 PMCID: PMC11216093 DOI: 10.3762/bjoc.20.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 06/18/2024] [Indexed: 07/03/2024] Open
Abstract
Halogen bonding permeates many areas of chemistry. A wide range of halogen-bond donors including neutral, cationic, monovalent, and hypervalent have been developed and studied. In this work we used density functional theory (DFT), natural bond orbital (NBO) theory, and quantum theory of atoms in molecules (QTAIM) to analyze aryl halogen-bond donors that are neutral, cationic, monovalent and hypervalent and in each series we include the halogens Cl, Br, I, and At. Within this diverse set of halogen-bond donors, we have found trends that relate halogen bond length with the van der Waals radii of the halogen and the non-covalent or partial covalency of the halogen bond. We have also developed a model to calculate ΔG of halogen-bond formation by the linear combination of the % p-orbital character on the halogen and energy of the σ-hole on the halogen-bond donor.
Collapse
Affiliation(s)
- Nicole Javaly
- Department of Chemistry, Portland State University, 1719 SW 10th Ave, Portland OR 97201, United States
| | - Theresa M McCormick
- Department of Chemistry, Portland State University, 1719 SW 10th Ave, Portland OR 97201, United States
| | - David R Stuart
- Department of Chemistry, Portland State University, 1719 SW 10th Ave, Portland OR 97201, United States
| |
Collapse
|
2
|
Otte F, Kleinheider J, Grabe B, Hiller W, Busse F, Wang R, Kreienborg NM, Merten C, Englert U, Strohmann C. Gauging the Strength of the Molecular Halogen Bond via Experimental Electron Density and Spectroscopy. ACS OMEGA 2023; 8:21531-21539. [PMID: 37360450 PMCID: PMC10286298 DOI: 10.1021/acsomega.3c00619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 04/19/2023] [Indexed: 06/28/2023]
Abstract
Strong and weak halogen bonds (XBs) in discrete aggregates involving the same acceptor are addressed by experiments in solution and in the solid state. Unsubstituted and perfluorinated iodobenzenes act as halogen donors of tunable strength; in all cases, quinuclidine represents the acceptor. NMR titrations reliably identify the strong intermolecular interactions in solution, with experimental binding energies of approx. 7 kJ/mol. Interaction of the σ hole at the halogen donor iodine leads to a redshift in the symmetric C-I stretching vibration; this shift reflects the interaction energy in the halogen-bonded adducts and may be assessed by Raman spectroscopy in condensed phase even for weak XBs. An experimental picture of the electronic density for the XBs is achieved by high-resolution X-ray diffraction on suitable crystals. Quantum theory of atoms in molecules (QTAIM) analysis affords the electron densities and energy densities in the bond critical points of the halogen bonds and confirms stronger interaction for the shorter contacts. For the first time, the experimental electron density shows a significant effect on the atomic volumes and Bader charges of the quinuclidine N atoms, the halogen-bond acceptor: strong and weak XBs are reflected in the nature of their acceptor atom. Our experimental findings at the acceptor atom match the discussed effects of halogen bonding and thus the proposed concepts in XB activated organocatalysis.
Collapse
Affiliation(s)
- Felix Otte
- Inorganic
Chemistry, TU Dortmund University, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Johannes Kleinheider
- Inorganic
Chemistry, TU Dortmund University, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Bastian Grabe
- Faculty
of Chemistry and Chemical Biology, TU Dortmund
University, Otto-Hahn-Str. 4a, 44227 Dortmund, Germany
| | - Wolf Hiller
- Faculty
of Chemistry and Chemical Biology, TU Dortmund
University, Otto-Hahn-Str. 4a, 44227 Dortmund, Germany
| | - Franziska Busse
- Inorganic
Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
| | - Ruimin Wang
- Inorganic
Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
- Institute
of Molecular Science, Shanxi University, Wucheng Road 92, 030006 Taiyuan, P. R. China
| | - Nora M. Kreienborg
- Organic Chemistry
II, Ruhr University Bochum, Universitätstraße 150, 44801 Bochum, Germany
| | - Christian Merten
- Organic Chemistry
II, Ruhr University Bochum, Universitätstraße 150, 44801 Bochum, Germany
| | - Ulli Englert
- Inorganic
Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany
- Institute
of Molecular Science, Shanxi University, Wucheng Road 92, 030006 Taiyuan, P. R. China
| | - Carsten Strohmann
- Inorganic
Chemistry, TU Dortmund University, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| |
Collapse
|
3
|
Robidas R, Reinhard DL, Huber SM, Legault CY. A Quantum-chemical Analysis on the Lewis Acidity of Diarylhalonium Ions. Chemphyschem 2023; 24:e202200634. [PMID: 36043491 PMCID: PMC10092059 DOI: 10.1002/cphc.202200634] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 08/30/2022] [Indexed: 01/07/2023]
Abstract
Cyclic diaryliodonium compounds like iodolium derivatives have increasingly found use as noncovalent Lewis acids in the last years. They are more stable toward nucleophilic substitution than acyclic systems and are markedly more Lewis acidic. Herein, this higher Lewis acidity is analyzed and explained via quantum-chemical calculations and energy decomposition analyses. Its key origin is the change in energy levels and hybridization of iodine's orbitals, leading to both more favorable electrostatic interaction and better charge transfer. Both of the latter seem to contribute in similar fashion, while hydrogen bonding as well as steric repulsion with the phenyl rings play at best a minor role. In comparison to iodolium, bromolium and chlorolium are less Lewis acidic the lighter the halogen, which is predominantly based on less favorable charge-transfer interactions.
Collapse
Affiliation(s)
- Raphaël Robidas
- Department of Chemistry, Université de Sherbrooke, Centre in Green Chemistry and Catalysis, J1K 2R1, Sherbrooke, Québec, Canada
| | - Dominik L Reinhard
- Fakultät für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Stefan M Huber
- Fakultät für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Claude Y Legault
- Department of Chemistry, Université de Sherbrooke, Centre in Green Chemistry and Catalysis, J1K 2R1, Sherbrooke, Québec, Canada
| |
Collapse
|
4
|
Steinke T, Wonner P, Gauld RM, Heinrich S, Huber SM. Catalytic Activation of Imines by Chalcogen Bond Donors in a Povarov [4+2] Cycloaddition Reaction. Chemistry 2022; 28:e202200917. [PMID: 35704037 PMCID: PMC9545453 DOI: 10.1002/chem.202200917] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Indexed: 12/15/2022]
Abstract
Recently, chalcogen bonding has been investigated in more detail in organocatalysis and the scope of activated functionalities continues to increase. Herein, the activation of imines in a Povarov [4+2] cycloaddition reaction with bidentate cationic chalcogen bond donors is presented. Tellurium-based Lewis acids show superior properties compared to selenium-based catalysts and inactive sulfur-based analogues. The catalytic activity of the chalcogen bonding donors increases with weaker binding anions. Triflate, however, is not suitable due to its participation in the catalytic pathway. A solvent screening revealed a more efficient activation in less polar solvents and a pronounced effect of solvent (and catalyst) on endo : exo diastereomeric ratio. Finally, new chiral chalcogen bonding catalysts were applied but provided only racemic mixtures of the product.
Collapse
Affiliation(s)
- Tim Steinke
- Fakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstraße 15044801BochumGermany
| | - Patrick Wonner
- Fakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstraße 15044801BochumGermany
| | - Richard M. Gauld
- Fakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstraße 15044801BochumGermany
| | - Sascha Heinrich
- Fakultät für Biologie und BiotechnologieRuhr-Universität BochumUniversitätsstraße 15044801BochumGermany
| | - Stefan M. Huber
- Fakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstraße 15044801BochumGermany
| |
Collapse
|
5
|
Karandikar SS, Bhattacharjee A, Metze BE, Javaly N, Valente EJ, McCormick TM, Stuart DR. Orbital analysis of bonding in diarylhalonium salts and relevance to periodic trends in structure and reactivity. Chem Sci 2022; 13:6532-6540. [PMID: 35756513 PMCID: PMC9172531 DOI: 10.1039/d2sc02332f] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 05/10/2022] [Indexed: 12/16/2022] Open
Abstract
Diarylhalonium compounds provide new opportunities as reagents and catalysts in the field of organic synthesis. The three center, four electron (3c-4e) bond is a center piece of their reactivity, but structural variation among the diarylhaloniums, and in comparison with other λ3-iodanes, indicates that the model needs refinement for broader applicability. We use a combination of Density Functional Theory (DFT), Natural Bond Orbital (NBO) Theory, and X-ray structure data to correlate bonding and structure for a λ3-iodane and a series of diarylchloronium, bromonium, and iodonium salts, and their isoelectronic diarylchalcogen counterparts. This analysis reveals that the s-orbital on the central halogen atom plays a greater role in the 3c-4e bond than previously considered. Finally, we show that our revised bonding model and associated structures account for both kinetic and thermodynamic reactivity for both acyclic phenyl(mesityl)halonium and cyclic dibenzohalolium salts.
Collapse
Affiliation(s)
| | - Avik Bhattacharjee
- Department of Chemistry, Portland State University Portland OR 97201 USA
| | - Bryan E Metze
- Department of Chemistry, Portland State University Portland OR 97201 USA
| | - Nicole Javaly
- Department of Chemistry, Portland State University Portland OR 97201 USA
| | - Edward J Valente
- Department of Chemistry, University of Portland Portland OR 97203 USA
| | | | - David R Stuart
- Department of Chemistry, Portland State University Portland OR 97201 USA
| |
Collapse
|
6
|
Völkel M, Engelage E, Kondratiuk M, Huber SM. Evaluation of 6‐halogenated 2‐pyridone moieties as halogen bond donors. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Martin Völkel
- Ruhr-Universität Bochum: Ruhr-Universitat Bochum Chemie und Biochemie GERMANY
| | - Elric Engelage
- Ruhr-Universität Bochum: Ruhr-Universitat Bochum Chemie und Biochemie GERMANY
| | - Mykhailo Kondratiuk
- Ruhr-Universität Bochum: Ruhr-Universitat Bochum Chemie und Biochemie GERMANY
| | - Stefan Matthias Huber
- Ruhr-Universität Bochum Fakultät für Chemie und Biochemie NC 4/171Universitätsstraße 150 44801 Bochum GERMANY
| |
Collapse
|
7
|
Wojtkowiak K, Jezierska A, Panek JJ. Revealing Intra- and Intermolecular Interactions Determining Physico-Chemical Features of Selected Quinolone Carboxylic Acid Derivatives. Molecules 2022; 27:2299. [PMID: 35408698 PMCID: PMC9000753 DOI: 10.3390/molecules27072299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 03/24/2022] [Accepted: 03/30/2022] [Indexed: 02/04/2023] Open
Abstract
The intra- and intermolecular interactions of selected quinolone carboxylic acid derivatives were studied in monomers, dimers and crystals. The investigated compounds are well-recognized as medicines or as bases for further studies in drug design. We employed density functional theory (DFT) in its classical formulation to develop gas-phase and solvent reaction field (PCM) models describing geometric, energetic and electronic structure parameters for monomers and dimers. The electronic structure was investigated based on the atoms in molecules (AIM) and natural bond orbital (NBO) theories. Special attention was devoted to the intramolecular hydrogen bonds (HB) present in the investigated compounds. The characterization of energy components was performed using symmetry-adapted perturbation theory (SAPT). Finally, the time-evolution methods of Car-Parrinello molecular dynamics (CPMD) and path integral molecular dynamics (PIMD) were employed to describe the hydrogen bond dynamics as well as the spectroscopic signatures. The vibrational features of the O-H stretching were studied using Fourier transformation of the autocorrelation function of atomic velocity. The inclusion of quantum nuclear effects provided an accurate depiction of the bridged proton delocalization. The CPMD and PIMD simulations were carried out in the gas and crystalline phases. It was found that the polar environment enhances the strength of the intramolecular hydrogen bonds. The SAPT analysis revealed that the dispersive forces are decisive factors in the intermolecular interactions. In the electronic ground state, the proton-transfer phenomena are not favourable. The CPMD results showed generally that the bridged proton is localized at the donor side, with possible proton-sharing events in the solid-phase simulation of stronger hydrogen bridges. However, the PIMD enabled the quantitative estimation of the quantum effects inclusion-the proton position was moved towards the bridge midpoint, but no qualitative changes were detected. It was found that the interatomic distance between the donor and acceptor atoms was shortened and that the bridged proton was strongly delocalized.
Collapse
Affiliation(s)
| | - Aneta Jezierska
- Faculty of Chemistry, University of Wrocław, ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland;
| | - Jarosław J. Panek
- Faculty of Chemistry, University of Wrocław, ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland;
| |
Collapse
|
8
|
Marzouk S, Ajili Y, Ben El Hadj Rhouma M, Ben Said R, Hochlaf M. Theoretical treatment of IO-X (X = N 2, CO, CO 2, H 2O) complexes. Phys Chem Chem Phys 2022; 24:7203-7213. [PMID: 35266935 DOI: 10.1039/d1cp05536d] [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
Iodine monoxide (IO) is an important component of the biogeochemical cycle of iodine. For instance, it is present in the troposphere, where it plays a crucial role in the physical chemical processes involving iodine containing compounds. Here, we present a theoretical study on a series of atmospherically relevant complexes of IO with N2, CO, CO2 and H2O, where their structural and spectroscopic properties and their interaction energies are computed. Calculations are carried out by means of ab initio post Hartree-Fock (RCCSD(T) and RMP2) methods and density functional theory DFT (PBE0 and M05-2X) based approaches with and without the inclusion of dispersion correction. After comparison to RCCSD(T), we highlight the good performance of M05-2X(+D3) DFT in describing the bonding between IO and X (X = N2, CO, CO2, H2O). Moreover, we found that the IO-X (X = N2, CO, CO2, H2O) complexes are formed by non-covalent interactions between the two monomers. In sum, we characterized two types of complexes: I-bonded and O-bonded, where the former is more stable. The atmospheric implications of the present findings are also discussed such as in the formation of the iodine oxide particles (IOPs).
Collapse
Affiliation(s)
- S Marzouk
- Laboratoire de Recherche d'Etude des Milieux Ionisés et Réactifs (EMIR), Institut Préparatoire aux Etudes d'Ingénieurs de Monastir, Université de Monastir, Tunisia.,Université Gustave Eiffel, COSYS/LISIS, 5 Bd Descartes 77454, Champs sur Marne, France.
| | - Y Ajili
- Laboratoire de Spectroscopie Atomique, Moléculaire et Applications - LSAMA, Université de Tunis-El Manar, Tunis, Tunisia
| | - M Ben El Hadj Rhouma
- Laboratoire de Recherche d'Etude des Milieux Ionisés et Réactifs (EMIR), Institut Préparatoire aux Etudes d'Ingénieurs de Monastir, Université de Monastir, Tunisia
| | - R Ben Said
- Department of Chemistry, College of Science and Arts, Qassim University, ArRass, Saudi Arabia
| | - M Hochlaf
- Université Gustave Eiffel, COSYS/LISIS, 5 Bd Descartes 77454, Champs sur Marne, France.
| |
Collapse
|
9
|
Decato DA, Sun J, Boller MR, Berryman OB. Pushing the Limits of the Hydrogen Bond Enhanced Halogen Bond —The Case of the C–H Hydrogen Bond. Chem Sci 2022; 13:11156-11162. [PMID: 36320486 PMCID: PMC9516949 DOI: 10.1039/d2sc03792k] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/31/2022] [Indexed: 11/21/2022] Open
Abstract
C–H hydrogen bonds have remarkable impacts on various chemical systems. Here we consider the influence of C–H hydrogen bonds to iodine atoms. Positioning a methyl group between two iodine halogen bond donors of the receptor engendered intramolecular C–H hydrogen bonding (HBing) to the electron-rich belt of both halogen bond donors. When coupled with control molecules, the role of the C–H hydrogen bond was evaluated. Gas-phase density functional theory studies indicated that methyl C–H hydrogen bonds help bias a bidentate binding conformation. Interaction energy analysis suggested that the charged C–H donors augment the halogen bond interaction—producing a >10 kcal mol−1 enhancement over a control lacking the C–H⋯I–C interaction. X-ray crystallographic analysis demonstrated C–H hydrogen bonds and bidentate conformations with triflate and iodide anions, yet the steric bulk of the central functional group seems to impact the expected trends in halogen bond distance. In solution, anion titration data indicated elevated performance from the receptors that utilize C–H Hydrogen Bond enhanced Halogen Bonds (HBeXBs). Collectively, the results suggest that even modest hydrogen bonds between C–H donors and iodine acceptors can influence molecular structure and improve receptor performance. C–H hydrogen bonds to iodine halogen bond donors are shown to improve halogen bonding and molecular preorganization.![]()
Collapse
Affiliation(s)
| | - Jiyu Sun
- University of Montana 32 Campus Drive Missoula MT USA
| | | | | |
Collapse
|
10
|
Zhao C, Sun C, Li X, Zeng Y. Aza‐Diels‐Alder Reaction of Danishefsky's Diene with Imine Catalyzed by N‐Heterocyclic Imidazole Halogen Bond Donors. ChemistrySelect 2021. [DOI: 10.1002/slct.202103487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Chang Zhao
- College of Chemistry and Materials Science Hebei Normal University Shijiazhuang 050024 China
| | - Cuihong Sun
- College of Chemical Engineering Shijiazhuang University Shijiazhuang 050035 China
| | - Xiaoyan Li
- College of Chemistry and Materials Science Hebei Normal University Shijiazhuang 050024 China
| | - Yanli Zeng
- College of Chemistry and Materials Science Hebei Normal University Shijiazhuang 050024 China
| |
Collapse
|
11
|
Scheiner S. Maximal occupation by bases of π-hole bands surrounding linear molecules. J Comput Chem 2021; 43:319-330. [PMID: 34859910 DOI: 10.1002/jcc.26792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/19/2022]
Abstract
Linear molecules such as CO2 contain a positive π-hole ring that surrounds C on the molecule's equator. Quantum calculations examine the question as to how many bases can simultaneously bind to this ring. Linear molecules examined are TO2 , where T = C, Si, Ge, Sn; bases are NCH and NH3 . CO2 engages in the weakest of the tetrel bonds, and can bind up to three NCH and two NH3 . Unlike σ-hole tetrel bonds, Si forms the strongest tetrel bonds, with interaction energies as high as 43 kcal/mol with NH3 . But like GeO2 , SiO2 can sustain only two bases in its equatorial ring. The π-hole ring of SnO2 can engage in up to four tetrel bonds with either NCH or NH3 , even though these bonds are weaker than those with GeO2 or SiO2 . As all of these complexes cast TO2 in the role of multiple electron acceptor, the resulting negative cooperativity makes each successive bond weaker than its predecessor as bases are added, as well as reducing the magnitude of the central molecule's π-hole.
Collapse
Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah, USA
| |
Collapse
|
12
|
Abstract
The list of σ-hole bonds is long and growing, encompassing both H-bonds and its closely related halogen, chalcogen, etc., sisters. These bonds rely on the asymmetric distribution of electron density, whose depletion along the extension of a covalent bond leaves a positive region of electrostatic potential from which these bonds derive their name. However, the density distributions of other molecules contain analogous positive regions that lie out of the molecular plane known as π-holes, which are likewise capable of engaging in noncovalent bonds. Quantum calculations are applied to study such π-hole bonds that involve linear molecules, whose positive region is a circular belt surrounding the molecule, rather than the more restricted area of a σ-hole. These bonds are examined in terms of their most fundamental elements arising from the spatial dispositions of their relevant molecular orbitals and the π-holes in both the total electron density and the electrostatic potential to which they lead. Systems examined comprise tetrel, chalcogen, aerogen, and triel bonds, as well as those involving group II elements, with atoms drawn from various rows of the Periodic Table. The π-hole bonds established by linear molecules tend to be weaker than those of comparable planar systems.
Collapse
Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, USA
| |
Collapse
|
13
|
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.
Collapse
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.
| |
Collapse
|
14
|
Yu S, Ward JS, Truong K, Rissanen K. Carbonyl Hypoiodites as Extremely Strong Halogen Bond Donors. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Shilin Yu
- Department of Chemistry University of Jyvaskyla Survontie 9 B 40014 Jyväskylä Finland
| | - Jas S. Ward
- Department of Chemistry University of Jyvaskyla Survontie 9 B 40014 Jyväskylä Finland
| | - Khai‐Nghi Truong
- Department of Chemistry University of Jyvaskyla Survontie 9 B 40014 Jyväskylä Finland
| | - Kari Rissanen
- Department of Chemistry University of Jyvaskyla Survontie 9 B 40014 Jyväskylä Finland
| |
Collapse
|
15
|
Yu S, Ward JS, Truong K, Rissanen K. Carbonyl Hypoiodites as Extremely Strong Halogen Bond Donors. Angew Chem Int Ed Engl 2021; 60:20739-20743. [PMID: 34268851 PMCID: PMC8518949 DOI: 10.1002/anie.202108126] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Indexed: 12/19/2022]
Abstract
Neutral halogen-bonded O-I-N complexes were prepared from in situ formed carbonyl hypoiodites and aromatic organic bases. The carbonyl hypoiodites have a strongly polarized iodine atom with larger σ-holes than any known uncharged halogen bond donor. Modulating the Lewis basicity of the selected pyridine derivatives and carboxylates leads to halogen-bonded complexes where the classical O-I⋅⋅⋅N halogen bond transforms more into a halogen-bonded COO- ⋅⋅⋅I-N+ ion-pair (salt) with an asymmetric O-I-N moiety. X-ray analyses, NMR studies, and calculations reveal the halogen bonding geometries of the carbonyl hypoiodite-based O-I-N complexes, confirming that in the solid-state the iodine atom is much closer to the N-atom of the pyridine derivatives than its original position at the carboxylate O-atom.
Collapse
Affiliation(s)
- Shilin Yu
- Department of ChemistryUniversity of JyvaskylaSurvontie 9 B40014JyväskyläFinland
| | - Jas S. Ward
- Department of ChemistryUniversity of JyvaskylaSurvontie 9 B40014JyväskyläFinland
| | - Khai‐Nghi Truong
- Department of ChemistryUniversity of JyvaskylaSurvontie 9 B40014JyväskyläFinland
| | - Kari Rissanen
- Department of ChemistryUniversity of JyvaskylaSurvontie 9 B40014JyväskyläFinland
| |
Collapse
|
16
|
Oliveira VP, Marcial BL, Machado FBC, Kraka E. Relating Bond Strength and Nature to the Thermodynamic Stability of Hypervalent Togni-Type Iodine Compounds. Chempluschem 2021; 86:1199-1210. [PMID: 34437775 DOI: 10.1002/cplu.202100285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 08/09/2021] [Indexed: 11/08/2022]
Abstract
The bond strength and nature of a set of 32 Togni-like reagents have been investigated at the M062X/def2-TZVP(D) level of theory in acetonitrile described with the SMD continuum solvent model, to rationalize the main factors responsible for their thermodynamic stability in different conformations, and trifluoromethylation capabilities. For the assessment of bond strength, we utilized local stretching force constants and associated bond strength orders, complemented with local features of the electron density to access the nature of the bonds. Bond dissociation energies varied from 31.6 to 79.9 kcal/mol depending on the polarizing power of the ligand trans to CF3 . Based on the analysis of the Laplacian of the density, we propose that the charge-shift bond character plays an important role in the stability of the molecules studied, especially for those containing I-O bonds. New insights on the trans influence and on possible ways to fine-tune the stability of these reagents are provided.
Collapse
Affiliation(s)
- Vytor Pinheiro Oliveira
- Instituto Tecnológico de Aeronáutica (ITA), Departamento de Química, São José dos Campos, 12228-900, São Paulo, Brazil
| | - Bruna Luana Marcial
- Instituto Federal Goiano (IF Goiano), Núcleo de Química, Campus Morrinhos, Goiás, Brazil
| | - Francisco B C Machado
- Instituto Tecnológico de Aeronáutica (ITA), Departamento de Química, São José dos Campos, 12228-900, São Paulo, Brazil
| | - Elfi Kraka
- Computational and Theoretical Chemistry Group (CATCO), Department of Chemistry, Southern Methodist University, 3215 Daniel Ave, Dallas, Texas, 75275-0314, USA
| |
Collapse
|
17
|
Scheiner S. Dissection of the Origin of π-Holes and the Noncovalent Bonds in Which They Engage. J Phys Chem A 2021; 125:6514-6528. [PMID: 34310147 DOI: 10.1021/acs.jpca.1c05431] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Accompanying the rapidly growing list of σ-hole bonds has come the acknowledgment of parallel sorts of noncovalent bonds which owe their stability in large part to a deficiency of electron density in the area above the molecular plane, known as a π-hole. The origins of these π-holes are probed for a wide series of molecules, comprising halogen, chalcogen, pnicogen, tetrel, aerogen, and spodium bonds. Much like in the case of their σ-hole counterparts, formation of the internal covalent π-bond in the Lewis acid molecule pulls density toward the bond midpoint and away from its extremities. This depletion of density above the central atom is amplified by an electron-withdrawing substituent. At the same time, the amplitude of the π*-orbital is enhanced in the region of the density-depleted π-hole, facilitating a better overlap with the nucleophile's lone pair orbital and a stabilizing n → π* charge transfer. The presence of lone pairs on the central atom acts to attenuate the π-hole and shift its position somewhat, resulting in an overall weakening of the π-hole bond. There is a tendency for π-hole bonds to include a higher fraction of induction energy than σ-bonds with proportionately smaller electrostatic and dispersion components, but this distinction is less a product of the σ- or π-character and more a function of the overall bond strength.
Collapse
Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, United States
| |
Collapse
|
18
|
Robidas R, Reinhard DL, Legault CY, Huber SM. Iodine(III)-Based Halogen Bond Donors: Properties and Applications. CHEM REC 2021; 21:1912-1927. [PMID: 34145711 DOI: 10.1002/tcr.202100119] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/21/2021] [Indexed: 12/24/2022]
Abstract
Halogen bonding, the non-covalent interaction of Lewis bases with an electron-deficient region of halogen substituents, received increased attention recently. Consequently, the design and evaluation of numerous halogen-containing species as halogen bond donors have been subject to intense research. More recently, organoiodine compounds at the iodine(III) state have been receiving growing attention in the field. Due to their electronic and structural properties, they provide access to unique binding modes. For this reason, our groups have been involved in the development of such compounds, in the quantification of their halogen bonding strength (through the evaluation of their Lewis acidities), as well as in the evaluation of their activities as catalysts in several model reactions. This account will describe these contributions.
Collapse
Affiliation(s)
- Raphaël Robidas
- Department of Chemistry, Université de Sherbrooke, J1K 2R1, Sherbrooke, Québec, Canada
| | - Dominik L Reinhard
- Fakultät für Chemie und Biochemie, Ruhr-Universität Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Claude Y Legault
- Department of Chemistry, Université de Sherbrooke, J1K 2R1, Sherbrooke, Québec, Canada
| | - Stefan M Huber
- Fakultät für Chemie und Biochemie, Ruhr-Universität Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| |
Collapse
|
19
|
Erdmann P, Greb L. Multidimensional Lewis Acidity: A Consistent Data Set of Chloride, Hydride, Methide, Water and Ammonia Affinities for 183 p-Block Element Lewis Acids. Chemphyschem 2021; 22:935-943. [PMID: 33755288 PMCID: PMC8252043 DOI: 10.1002/cphc.202100150] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/22/2021] [Indexed: 11/17/2022]
Abstract
The computed fluoride ion affinity (FIA) is a widely applied descriptor to gauge Lewis acidity. Like every other single-parameter Lewis acidity scale, the FIA metric suffers from the one-dimensionality, that prohibits addressing Lewis acidity by the multidimensionality it inherently requires (i. e., reference Lewis base dependency). However, a systematic screening of computed affinities other than the FIA is much less developed. Herein, we extended our CCSD(T)/CBS benchmark of different density functionals and the DLPNO-CCSD(T) method for chloride (CIA), methide (MIA), hydride (HIA), water (WA), and ammonia (AA) affinities. The best performing methods are subsequently applied to yield nearly 800 affinities for 183 p-block element compounds of group 13-16 with an estimated accuracy of <10 kJ mol-1 . The study's output serves as a consistent library for qualitative analyses and a training set for future statistical approaches. A first holistic correlation analysis underscores the need for a multidimensional description of Lewis acidity.
Collapse
Affiliation(s)
- Philipp Erdmann
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120Heidelberg
| | - Lutz Greb
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120Heidelberg
| |
Collapse
|
20
|
Abstract
We systematically investigated iodine–metal and iodine–iodine bonding in van Koten’s pincer complex and 19 modifications changing substituents and/or the transition metal with a PBE0–D3(BJ)/aug–cc–pVTZ/PP(M,I) model chemistry. As a novel tool for the quantitative assessment of the iodine–metal and iodine–iodine bond strength in these complexes we used the local mode analysis, originally introduced by Konkoli and Cremer, complemented with NBO and Bader’s QTAIM analyses. Our study reveals the major electronic effects in the catalytic activity of the M–I–I non-classical three-center bond of the pincer complex, which is involved in the oxidative addition of molecular iodine I2 to the metal center. According to our investigations the charge transfer from the metal to the σ* antibonding orbital of the I–I bond changes the 3c–4e character of the M–I–I three-center bond, which leads to weakening of the iodine I–I bond and strengthening of the metal–iodine M–I bond, facilitating in this way the oxidative addition of I2 to the metal. The charge transfer can be systematically modified by substitution at different places of the pincer complex and by different transition metals, changing the strength of both the M–I and the I2 bonds. We also modeled for the original pincer complex how solvents with different polarity influence the 3c–4e character of the M–I–I bond. Our results provide new guidelines for the design of pincer complexes with specific iodine–metal bond strengths and introduce the local vibrational mode analysis as an efficient tool to assess the bond strength in complexes.
Collapse
|
21
|
Heinen F, Reinhard DL, Engelage E, Huber SM. A Bidentate Iodine(III)-Based Halogen-Bond Donor as a Powerful Organocatalyst*. Angew Chem Int Ed Engl 2021; 60:5069-5073. [PMID: 33215804 PMCID: PMC7986438 DOI: 10.1002/anie.202013172] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/11/2020] [Indexed: 12/12/2022]
Abstract
In contrast to iodine(I)-based halogen bond donors, iodine(III)-derived ones have only been used as Lewis acidic organocatalysts in a handful of examples, and in all cases they acted in a monodentate fashion. Herein, we report the first application of a bidentate bis(iodolium) salt as organocatalyst in a Michael and a nitro-Michael addition reaction as well as in a Diels-Alder reaction that had not been activated by noncovalent organocatalysts before. In all cases, the performance of this bidentate XB donor distinctly surpassed the one of arguably the currently strongest iodine(I)-based organocatalyst. Bidentate coordination to the substrate was corroborated by a structural analysis and by DFT calculations of the transition states. Overall, the catalytic activity of the bis(iodolium) system approaches that of strong Lewis acids like BF3 .
Collapse
Affiliation(s)
- Flemming Heinen
- Fakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstrasse 15044801BochumGermany
| | - Dominik L. Reinhard
- Fakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstrasse 15044801BochumGermany
| | - Elric Engelage
- Fakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstrasse 15044801BochumGermany
| | - Stefan M. Huber
- Fakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstrasse 15044801BochumGermany
| |
Collapse
|
22
|
Robidas R, Legault CY, Huber SM. A low cost, high accuracy method for halogen bonding complexes. Phys Chem Chem Phys 2021; 23:3041-3049. [PMID: 33480927 DOI: 10.1039/d0cp05614f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The ONIOM scheme M052X/[Def2TZVP+Def2TZVPD.ECP(I)]:AM1 is shown to represent halogen bond (XB) geometries nearly as well as DFT while being more than two orders of magnitude faster in systems containing >40 atoms. This finding is shown to hold for 40 XB donors, which cover most known backbones, and for a range of neutral and anionic Lewis bases. Complexation free energies can be accurately computed using these geometries and a single-point energy calculation at the DFT level. This approach circumvents the unfavorable scaling of computing time associated with modeling large systems involving halogen bonding.
Collapse
Affiliation(s)
- Raphaël Robidas
- Department of Chemistry, Université de Sherbrooke, 2500 boul. de l'Université, Sherbrooke, Québec J1K 2R1, Canada.
| | - Claude Y Legault
- Department of Chemistry, Université de Sherbrooke, 2500 boul. de l'Université, Sherbrooke, Québec J1K 2R1, Canada.
| | - Stefan M Huber
- Department of Chemistry and Biochemistry, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| |
Collapse
|
23
|
Heinen F, Reinhard DL, Engelage E, Huber SM. Ein zweizähniger Iod(III)‐basierter Halogenbrückendonor als leistungsfähiger Organokatalysator**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202013172] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Flemming Heinen
- Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
| | - Dominik L. Reinhard
- Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
| | - Elric Engelage
- Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
| | - Stefan M. Huber
- Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
| |
Collapse
|
24
|
Bhattarai S, Sutradhar D, Chandra AK. Tuning of halogen-bond strength: Comparative role of basicity and strength of σ-hole. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2020.129239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
25
|
Sethio D, Raggi G, Lindh R, Erdélyi M. Halogen Bond of Halonium Ions: Benchmarking DFT Methods for the Description of NMR Chemical Shifts. J Chem Theory Comput 2020; 16:7690-7701. [PMID: 33136388 PMCID: PMC7726912 DOI: 10.1021/acs.jctc.0c00860] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Indexed: 12/20/2022]
Abstract
Because of their anisotropic electron distribution and electron deficiency, halonium ions are unusually strong halogen-bond donors that form strong and directional three-center, four-electron halogen bonds. These halogen bonds have received considerable attention owing to their applicability in supramolecular and synthetic chemistry and have been intensely studied using spectroscopic and crystallographic techniques over the past decade. Their computational treatment faces different challenges to those of conventional weak and neutral halogen bonds. Literature studies have used a variety of wave functions and DFT functionals for prediction of their geometries and NMR chemical shifts, however, without any systematic evaluation of the accuracy of these methods being available. In order to provide guidance for future studies, we present the assessment of the accuracy of 12 common DFT functionals along with the Hartree-Fock (HF) and the second-order Møller-Plesset perturbation theory (MP2) methods, selected from an initial set of 36 prescreened functionals, for the prediction of 1H, 13C, and 15N NMR chemical shifts of [N-X-N]+ halogen-bond complexes, where X = F, Cl, Br, and I. Using a benchmark set of 14 complexes, providing 170 high-quality experimental chemical shifts, we show that the choice of the DFT functional is more important than that of the basis set. The M06 functional in combination with the aug-cc-pVTZ basis set is demonstrated to provide the overall most accurate NMR chemical shifts, whereas LC-ωPBE, ωB97X-D, LC-TPSS, CAM-B3LYP, and B3LYP to show acceptable performance. Our results are expected to provide a guideline to facilitate future developments and applications of the [N-X-N]+ halogen bond.
Collapse
Affiliation(s)
- Daniel Sethio
- Department of Chemistry—BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
| | - Gerardo Raggi
- Department of Chemistry—BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
| | - Roland Lindh
- Department of Chemistry—BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
| | - Máté Erdélyi
- Department of Chemistry—BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
| |
Collapse
|
26
|
Affiliation(s)
- Martin Breugst
- Department für Chemie Universität zu Köln Greinstraße 4 50939 Köln Germany
| | - Jonas J. Koenig
- Department für Chemie Universität zu Köln Greinstraße 4 50939 Köln Germany
| |
Collapse
|
27
|
Heinen F, Engelage E, Cramer CJ, Huber SM. Hypervalent Iodine(III) Compounds as Biaxial Halogen Bond Donors. J Am Chem Soc 2020; 142:8633-8640. [PMID: 32286829 PMCID: PMC7252947 DOI: 10.1021/jacs.9b13309] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
![]()
“Hypervalent”
iodine(III) derivatives have been established as powerful reagents
in organic transformations, but so far only a handful of studies have
addressed their potential use as halogen-bonding noncovalent Lewis
acids. In contrast to “classical” halogen-bond donors
based on iodine(I) compounds, iodine(III) salts feature two directional
electrophilic axes perpendicular to each other. Herein we present
the first systematic investigation on biaxial binding to such Lewis
acids in solution. To this end, hindered and unhindered iodolium species
were titrated with various substrates, including diesters and diamides,
via 1H NMR spectroscopy and isothermal titration calorimetry.
Clear evidence for biaxial binding was obtained in two model systems,
and the association strengths increased by 2 orders of magnitude.
These findings were corroborated by density functional theory calculations
(which reproduced the trend well but underestimated the absolute binding
constants) and a cocrystal featuring biaxial coordination of a diamide
to the unhindered iodolium compound.
Collapse
Affiliation(s)
- Flemming Heinen
- Fakultät für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150,44801 Bochum, Germany
| | - Elric Engelage
- Fakultät für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150,44801 Bochum, Germany
| | - Christopher J Cramer
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, 207 Pleasant Street SE, Minneapolis 55455-0431, Minnesota, United States
| | - Stefan M Huber
- Fakultät für Chemie und Biochemie, Organische Chemie I, Ruhr-Universität Bochum, Universitätsstraße 150,44801 Bochum, Germany
| |
Collapse
|
28
|
Engelage E, Reinhard D, Huber SM. Is There a Single Ideal Parameter for Halogen-Bonding-Based Lewis Acidity? Chemistry 2020; 26:3843-3861. [PMID: 31943430 PMCID: PMC7154672 DOI: 10.1002/chem.201905273] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Indexed: 01/08/2023]
Abstract
Halogen-bond donors (halogen-based Lewis acids) have now found various applications in diverse fields of chemistry. The goal of this study was to identify a parameter obtainable from a single DFT calculation that reliably describes halogen-bonding strength (Lewis acidity). First, several DFT methods were benchmarked against the CCSD(T) CBS binding data of complexes of 17 carbon-based halogen-bond donors with chloride and ammonia as representative Lewis bases, which revealed M05-2X with a partially augmented def2-TZVP(D) basis set as the best model chemistry. The best single parameter to predict halogen-bonding strengths was the static σ-hole depth, but it still provided inaccurate predictions for a series of compounds. Thus, a more reliable parameter, Ωσ* , has been developed through the linear combination of the σ-hole depth and the σ*(C-I) energy, which was further validated against neutral, cationic, halogen- and nitrogen-based halogen-bond donors with very good performance.
Collapse
Affiliation(s)
- Elric Engelage
- Organische Chemie IFakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstraße 15044801BochumGermany
| | - Dominik Reinhard
- Organische Chemie IFakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstraße 15044801BochumGermany
| | - Stefan M. Huber
- Organische Chemie IFakultät für Chemie und BiochemieRuhr-Universität BochumUniversitätsstraße 15044801BochumGermany
| |
Collapse
|