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Eder J, Antonov AS, Tupikina EY, Gschwind RM. Chiral Diselenophosphoric Acids for Ion Pair Catalysis: A Novel Approach to Enhance Both Proton Donating and Proton Accepting Properties. Chemistry 2024; 30:e202401793. [PMID: 38747423 DOI: 10.1002/chem.202401793] [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: 05/07/2024] [Indexed: 07/18/2024]
Abstract
The activation of poorly reactive substrates via strong chiral acids is a central topic in asymmetric ion pair catalysis these days. Despite highly successful scaffolds such as N-triflylphosphoramides, these catalysts either lack C2-symmetry or provide multiple H-bond acceptor sites, leading to lower ee values for certain reactions. We present BINOL-based diselenophosphoric acids (DSA) as an extremely promising alternative. Using an intertwined approach of synthesis and NMR studies, we developed a synthetic approach to DSA with up to 98 % NMR yield. The obtained acids provide both very high proton donor and proton acceptor properties, a bifunctionality, which is key to catalytic applications. Indeed, first reactivity test proved the much higher acidity of DSA and its ability to initiate Mukaiyama-Mannich reaction and protodesilylation of silyl ethers. Together with their C2-symmetry, the single donor and single acceptor situation, the decreased tendency of self-association, and the straightforward synthesis with potential 3,3'-substitution, the DSA provide all features ideal for the further development of ion pair catalysis.
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Affiliation(s)
- Johannes Eder
- Institute of Organic Chemistry, University of Regensburg, D-93053, Regensburg, Germany
| | - Alexander S Antonov
- Institute of Organic Chemistry, University of Regensburg, D-93053, Regensburg, Germany
| | - Elena Yu Tupikina
- Institute of Chemistry, St. Petersburg State University, 198504, St. Petersburg, Russian Federation
| | - Ruth M Gschwind
- Institute of Organic Chemistry, University of Regensburg, D-93053, Regensburg, Germany
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2
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Krutin DV, Zakharov AS, Tupikina EY, Mulloyarova VV. Unveiling the electronic structure peculiarities of phosphine selenides as NMR probes for non-covalent interactions: an experimental and theoretical study. Phys Chem Chem Phys 2024. [PMID: 39023050 DOI: 10.1039/d4cp01191k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
In this work, R3PSe (R = Me, Et, n-Bu, t-Bu and Ph) were studied experimentally using NMR spectroscopy in solution and the solid-state in combinaton with quantum chemical methods. The study shows that the NMR parameters of these phosphine selenides, such as δP, δSe, and 1JPSe, are sensitive to subtle changes in the electronic environment of the P and Se atoms. Consequently, phosphine selenides R3PSe can serve as promising spectral probes for the detection and quantitative investigation of various non-covalent interactions. Additionally, the variations of R in phosphine selenides influence the observed NMR spectral parameters, primarily through effects such as π-backdonation and hyperconjugation, which have been observed experimentally and confirmed theoretically.
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Affiliation(s)
- Danil V Krutin
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
| | - Anton S Zakharov
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
| | - Elena Yu Tupikina
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
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3
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Chakalov ER, Shekurov RP, Miluykov VA, Tolstoy PM. Evidence of extremely short hydrogen bond in the homoconjugated ferrocene-1,1'-diyl-bisphosphinic acid anion: sign change of the H/D isotope effect on the 31P NMR chemical shift. Phys Chem Chem Phys 2023; 25:29486-29495. [PMID: 37888828 DOI: 10.1039/d3cp03714b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
The structure of the two intramolecular hydrogen-bonded motifs within ferrocene-1,1'-diyl-bisphosphinic acid, a cyclic dimer and a homoconjugated anion, has been experimentally revealed by NMR spectroscopy for a solution in a low-freezing polar aprotic CDF3/CDF2Cl medium at 100 K. Structure elucidation was achieved with the help of the H/D isotope effects on the 1H, 2H and, for the first time, 31P NMR chemical shifts. The questions of bridging hydron localization and origins of opposite signs of H/D isotope effects on the 31P NMR chemical shifts in the cyclic dimer and homoconjugated anion have also been addressed by DFT calculations, including numerical solution of the Schrödinger equation for proton and deuteron vibrations in the anharmonic double well potentials.
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Affiliation(s)
- E R Chakalov
- Institute of Chemistry, St. Petersburg State University, Russia.
| | - R P Shekurov
- A.E. Arbuzov Institute of Organic and Physical Chemistry, RAS, Russia
| | - V A Miluykov
- A.E. Arbuzov Institute of Organic and Physical Chemistry, RAS, Russia
| | - P M Tolstoy
- Institute of Chemistry, St. Petersburg State University, Russia.
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4
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Nazarski RB. On the Use of Deuterated Organic Solvents without TMS to Report 1H/ 13C NMR Spectral Data of Organic Compounds: Current State of the Method, Its Pitfalls and Benefits, and Related Issues. Molecules 2023; 28:4369. [PMID: 37298845 PMCID: PMC10254718 DOI: 10.3390/molecules28114369] [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: 04/29/2023] [Revised: 05/22/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023] Open
Abstract
The quite popular, simple but imperfect method of referencing NMR spectra to residual 1H and 13C signals of TMS-free deuterated organic solvents (referred to as Method A) is critically discussed for six commonly used NMR solvents with respect to their δH and δC values that exist in the literature. Taking into account the most reliable data, it was possible to recommend 'best' δX values for such secondary internal standards. The position of these reference points on the δ scale strongly depends on the concentration and type of analyte under study and the solvent medium used. For some solvents, chemically induced shifts (CISs) of residual 1H lines were considered, also taking into account the formation of 1:1 molecular complexes (for CDCl3). Typical potential errors that can occur as a result of improper application of Method A are considered in detail. An overview of all found δX values adopted by users of this method revealed a discrepancy of up to 1.9 ppm in δC reported for CDCl3, most likely caused by the CIS mentioned above. The drawbacks of Method A are discussed in relation to the classical use of an internal standard (Method B), two 'instrumental' schemes in which Method A is often implicitly applied, that is, the default Method C using 2H lock frequencies and Method D based on Ξ values, recommended by the IUPAC but only occasionally used for 1H/13C spectra, and external referencing (Method E). Analysis of current needs and opportunities for NMR spectrometers led to the conclusion that, for the most accurate application of Method A, it is necessary to (a) use dilute solutions in a single NMR solvent and (b) to report δX data applied for the reference 1H/13C signals to the nearest 0.001/0.01 ppm to ensure the precise characterization of new synthesized or isolated organic systems, especially those with complex or unexpected structures. However, the use of TMS in Method B is strongly recommended in all such cases.
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Affiliation(s)
- Ryszard B Nazarski
- Theoretical and Structural Chemistry Group, Department of Physical Chemistry, Faculty of Chemistry, University of Lodz, 163/165 Pomorska, 90-236 Łódź, Poland
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5
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Tupikina EY, Korostelev VO, Krutin DV, Tolstoy PM. Evolution of vibrational bands upon gradual protonation/deprotonation of arsinic acid H 2As(O)OH in media of different polarity. Phys Chem Chem Phys 2023; 25:8664-8675. [PMID: 36891959 DOI: 10.1039/d2cp06060d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
This computational work is devoted to the investigation (MP2/def2-TZVP) of the geometry and IR parameters of arsinic acid H2AsOOH and its hydrogen-bonded complexes under vacuum and in media with different polarity. The medium effects were accounted for in two ways: (1) implicitly, using the IEFPCM model, varying the dielectric permittivity (ε) and (2) explicitly, by considering hydrogen-bonded complexes of H2As(O)OH with various hydrogen bond donors (41 complexes) or acceptors (38 complexes), imitating a gradual transition to the As(OH)2+ or AsO2- moiety, respectively. It was shown that the transition from vacuum to a medium with ε > 1 causes the As(O)OH fragment to lose its flatness. The solvent polar medium introduces significant changes in the geometry and IR spectral parameters of hydrogen-bonded complexes too: as the polarity of a medium increases, weak hydrogen bonds become weaker, and strong and medium hydrogen bonds become stronger; in the case of a complex with two hydrogen bonds cooperativity effects are observed. In almost all cases the driving force of these changes appears to be preferential solvation of charge-separated structures. In the limiting case of complete deprotonation (or conversely complete protonation) the vibrational frequencies of νAsO and νAs-O turn into νAs-O(asym) and νAs-O(sym), respectively. In the intermediate cases the distance between νAsO and νAs-O is sensitive to both implicit solvation and explicit solvation and the systematic changes of this distance can be used for estimation of the degree of proton transfer within the hydrogen bond.
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Affiliation(s)
- Elena Yu Tupikina
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
| | | | - Danil V Krutin
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
| | - Peter M Tolstoy
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
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Hansen PE. Isotope Effects on Chemical Shifts in the Study of Hydrogen Bonds in Small Molecules. Molecules 2022; 27:2405. [PMID: 35458603 PMCID: PMC9026942 DOI: 10.3390/molecules27082405] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/03/2022] [Accepted: 04/05/2022] [Indexed: 11/16/2022] Open
Abstract
This review is giving a short introduction to the techniques used to investigate isotope effects on NMR chemical shifts. The review is discussing how isotope effects on chemical shifts can be used to elucidate the importance of either intra- or intermolecular hydrogen bonding in ionic liquids, of ammonium ions in a confined space, how isotope effects can help define dimers, trimers, etc., how isotope effects can lead to structural parameters such as distances and give information about ion pairing. Tautomerism is by advantage investigated by isotope effects on chemical shifts both in symmetric and asymmetric systems. The relationship between hydrogen bond energies and two-bond deuterium isotope effects on chemical shifts is described. Finally, theoretical calculations to obtain isotope effects on chemical shifts are looked into.
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Affiliation(s)
- Poul Erik Hansen
- Department of Science and Environment, Roskilde University, Universitetsvej 1, DK-4000 Roskilde, Denmark
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7
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Yakubenko AA, Puzyk AM, Korostelev VO, Mulloyarova VV, Tupikina EY, Tolstoy PM, Antonov AS. Self-association of diphenylpnictoginic acids in solution and solid state: covalent vs. hydrogen bonding. Phys Chem Chem Phys 2022; 24:7882-7892. [PMID: 35302575 DOI: 10.1039/d2cp00286h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Triphenylpnictogens were oxidized to access diphenylpnictioginic acids Ph2XOOH (X = P, As, Sb, Bi). It was shown that oxidation with chloramine-T does not lead to the cleavage of a C-pnictogen bond. The preliminary reductive cleavage with sodium in liquid ammonia followed by the oxidation with hydrogen peroxide was successfully utilised for the synthesis of diphenylphosphinic and diphenylarsinic acids. It was shown that in solid state (by means of XRD), all diphenylpnictoginic acids form polymeric chains. Diphenylbismuthinic and diphenylantimonic acids form polymeric covalent adducts, while diphenylphosphinic and diphenylarsinic chains are associated through hydrogen bonding. Unlike diphenylphosphinic acid, diphenilarsinic acid forms two polymorphs of hydrogen-bonded infinite chains. In solution in a polar aprotic solvent diphenylarsinic acid, similarly to dimethylarsinic, forms hydrogen-bonded cyclic dimers together with a small amount of cyclic trimers.
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Affiliation(s)
- Artyom A Yakubenko
- St. Petersburg State University, Institute of Chemistry, Universitetskii pr. 26, 198504 St. Petersburg, Russian Federation
| | - Aleksandra M Puzyk
- St. Petersburg State University, Institute of Chemistry, Universitetskii pr. 26, 198504 St. Petersburg, Russian Federation
| | - Vladislav O Korostelev
- St. Petersburg State University, Institute of Chemistry, Universitetskii pr. 26, 198504 St. Petersburg, Russian Federation
| | - Valeriia V Mulloyarova
- St. Petersburg State University, Institute of Chemistry, Universitetskii pr. 26, 198504 St. Petersburg, Russian Federation
| | - Elena Yu Tupikina
- St. Petersburg State University, Institute of Chemistry, Universitetskii pr. 26, 198504 St. Petersburg, Russian Federation
| | - Peter M Tolstoy
- St. Petersburg State University, Institute of Chemistry, Universitetskii pr. 26, 198504 St. Petersburg, Russian Federation
| | - Alexander S Antonov
- St. Petersburg State University, Institute of Chemistry, Universitetskii pr. 26, 198504 St. Petersburg, Russian Federation
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8
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Kostin MA, Pylaeva S, Tolstoy P. Phosphine oxides as NMR and IR spectroscopic probes for geometry and energy of PO···H–A hydrogen bonds. Phys Chem Chem Phys 2022; 24:7121-7133. [DOI: 10.1039/d1cp05939d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work we evaluate the possibility to use the NMR and IR spectral properties of P=O group to estimate the geometry and strength of hydrogen bonds which it forms...
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9
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Koeppe B, Tolstoy PM, Guo J, Denisov GS, Limbach HH. Combined NMR and UV-Vis Spectroscopic Studies of Models for the Hydrogen Bond System in the Active Site of Photoactive Yellow Protein: H-Bond Cooperativity and Medium Effects. J Phys Chem B 2021; 125:5874-5884. [PMID: 34060830 DOI: 10.1021/acs.jpcb.0c09923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Intramolecular hydrogen bonds in aprotic media were studied by combined (simultaneous) NMR and UV-vis spectroscopy. The species under investigation were anionic and featured single or coupled H-bonds between, for example, carboxylic groups and phenolic oxygen atoms (COO···H···OC)-, among phenolic oxygen atoms (CO···H···OC)-, and hydrogen bond chains between a carboxylic group and two phenolic oxygen atoms (COO···H···(OC)···H···OC)-. The last anion may be regarded as a small molecule model for the hydrogen bond system in the active site of wild-type photoactive yellow protein (PYP) while the others mimic the corresponding H-bonds in site-selective mutants. Proton positions in isolated hydrogen bonds and hydrogen bond chains were assessed by calculations for vacuum conditions and spectroscopically for the two media, CD2Cl2 and the liquefied gas mixture CDClF2/CDF3 at low temperatures. NMR parameters allow for the estimation of time-averaged H-bond geometries, and optical spectra give additional information about geometry distributions. Comparison of the results from the various systems revealed the effects of the formation of hydrogen bond chains and changes of medium conditions on the geometry of individual H-bonds. In particular, the proton in a hydrogen bond to a carboxylic group shifts from the phenolic oxygen atom in the system COO-···H-OC to the carboxylic group in COO-H···(OC)-···H-OC as a result of hydrogen bond formation to the additional phenolic donor. Increase in medium polarity may, however, induce the conversion of a structure of a type COO-H···(OC)-···H-OC to the type COO-···H-(OC)···H-OC. Application of these results obtained from the model systems to PYP suggests that both cooperative effects within the hydrogen bond chain and a low-polarity protein environment are prerequisites for the stabilization of negative charge on the cofactor and hence for the spectral tuning of the photoreceptor.
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Affiliation(s)
- Benjamin Koeppe
- J. Heyrovský Institute of Physical Chemistry, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
| | - Peter M Tolstoy
- Institute of Chemistry, St. Petersburg State University, Universitetskij pr. 26, 198504 St. Petersburg, Russia
| | - Jing Guo
- Department of Radiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Gleb S Denisov
- Department of Physics, St. Petersburg State University, 198504 St. Petersburg, Russian Federation
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10
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Mulloyarova VV, Puzyk AM, Efimova AA, Antonov AS, Evarestov RA, Aliyarova IS, Asfin RE, Tolstoy PM. Solid-state and solution-state self-association of dimethylarsinic acid: IR, NMR and theoretical study. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.130176] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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11
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Actual Symmetry of Symmetric Molecular Adducts in the Gas Phase, Solution and in the Solid State. Symmetry (Basel) 2021. [DOI: 10.3390/sym13050756] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
This review discusses molecular adducts, whose composition allows a symmetric structure. Such adducts are popular model systems, as they are useful for analyzing the effect of structure on the property selected for study since they allow one to reduce the number of parameters. The main objectives of this discussion are to evaluate the influence of the surroundings on the symmetry of these adducts, steric hindrances within the adducts, competition between different noncovalent interactions responsible for stabilizing the adducts, and experimental methods that can be used to study the symmetry at different time scales. This review considers the following central binding units: hydrogen (proton), halogen (anion), metal (cation), water (hydrogen peroxide).
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Shenderovich IG. 1,3,5-Triaza-7-Phosphaadamantane (PTA) as a 31P NMR Probe for Organometallic Transition Metal Complexes in Solution. Molecules 2021; 26:molecules26051390. [PMID: 33806666 PMCID: PMC7961616 DOI: 10.3390/molecules26051390] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/01/2021] [Accepted: 03/01/2021] [Indexed: 11/16/2022] Open
Abstract
Due to the rigid structure of 1,3,5-triaza-7-phosphaadamantane (PTA), its 31P chemical shift solely depends on non-covalent interactions in which the molecule is involved. The maximum range of change caused by the most common of these, hydrogen bonding, is only 6 ppm, because the active site is one of the PTA nitrogen atoms. In contrast, when the PTA phosphorus atom is coordinated to a metal, the range of change exceeds 100 ppm. This feature can be used to support or reject specific structural models of organometallic transition metal complexes in solution by comparing the experimental and Density Functional Theory (DFT) calculated values of this 31P chemical shift. This approach has been tested on a variety of the metals of groups 8-12 and molecular structures. General recommendations for appropriate basis sets are reported.
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Affiliation(s)
- Ilya G Shenderovich
- Institute of Organic Chemistry, University of Regensburg, Universitaetstrasse 31, 93053 Regensburg, Germany
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13
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Abstract
The self-association of phosphonic acids with general formula RP(O)(OH)2 in solution state remains largely unexplored. The general understanding is that such molecules form multiple intermolecular hydrogen bonds, but the stoichiometry of self-associates and the bonding motifs are unclear. In this work, we report the results of the study of self-association of tert-butylphosphonic acid using low temperature liquid-state 1H and 31P NMR spectroscopy (100 K; CDF3/CDF2Cl) and density functional theory (DFT) calculations. For the first time, we demonstrate conclusively that polar aprotic medium tert-butylphosphonic acid forms highly symmetric cage-like tetramers held by eight OHO hydrogen bonds, which makes the complex quite stable. In these associates. each phosphonic acid molecule is bonded to three other molecules by forming two hydrogen bonds as proton donor and two hydrogen bonds as proton acceptor. Though the structure of such cage-like tetramers is close to tetrahedral, the formal symmetry of the self-associate is C2.
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Jóźwiak K, Jezierska A, Panek JJ, Goremychkin EA, Tolstoy PM, Shenderovich IG, Filarowski A. Inter- vs. Intramolecular Hydrogen Bond Patterns and Proton Dynamics in Nitrophthalic Acid Associates. Molecules 2020; 25:E4720. [PMID: 33066679 PMCID: PMC7587347 DOI: 10.3390/molecules25204720] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 01/18/2023] Open
Abstract
Noncovalent interactions are among the main tools of molecular engineering. Rational molecular design requires knowledge about a result of interplay between given structural moieties within a given phase state. We herein report a study of intra- and intermolecular interactions of 3-nitrophthalic and 4-nitrophthalic acids in the gas, liquid, and solid phases. A combination of the Infrared, Raman, Nuclear Magnetic Resonance, and Incoherent Inelastic Neutron Scattering spectroscopies and the Car-Parrinello Molecular Dynamics and Density Functional Theory calculations was used. This integrated approach made it possible to assess the balance of repulsive and attractive intramolecular interactions between adjacent carboxyl groups as well as to study the dependence of this balance on steric confinement and the effect of this balance on intermolecular interactions of the carboxyl groups.
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Affiliation(s)
- Kinga Jóźwiak
- Faculty of Chemistry, University of Wrocław 14 F. Joliot-Curie str., 50-383 Wrocław, Poland; (K.J.); (A.J.); (J.J.P.)
| | - Aneta Jezierska
- Faculty of Chemistry, University of Wrocław 14 F. Joliot-Curie str., 50-383 Wrocław, Poland; (K.J.); (A.J.); (J.J.P.)
| | - Jarosław J. Panek
- Faculty of Chemistry, University of Wrocław 14 F. Joliot-Curie str., 50-383 Wrocław, Poland; (K.J.); (A.J.); (J.J.P.)
| | - Eugene A. Goremychkin
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research 6 F. Joliot-Curie str., 141980 Dubna, Russia;
| | - Peter M. Tolstoy
- Institute of Chemistry, St. Petersburg State University, Universitetskij pr. 26, 198504 St. Petersburg, Russia;
| | - Ilya G. Shenderovich
- Institute of Organic Chemistry, University of Regensburg, Universitaetstrasse 31, 93053 Regensburg, Germany
| | - Aleksander Filarowski
- Faculty of Chemistry, University of Wrocław 14 F. Joliot-Curie str., 50-383 Wrocław, Poland; (K.J.); (A.J.); (J.J.P.)
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