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Aiello F, Uccello Barretta G, Balzano F, Spiaggia F. The Phenomenon of Self-Induced Diastereomeric Anisochrony and Its Implications in NMR Spectroscopy. Molecules 2023; 28:6854. [PMID: 37836697 PMCID: PMC10574224 DOI: 10.3390/molecules28196854] [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: 09/01/2023] [Revised: 09/21/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023] Open
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is an analytical technique largely applied in the analysis of discrimination processes involving enantiomeric substrates and chiral agents, which can interact with the analyte either via covalent bonding or via formation of diastereomeric solvates. However, enantiodiscrimination has been observed, in some cases, even in the absence of any additional chiral selector. The reasons behind this phenomenon must be found in the capability of some chiral substrates to interact with themselves by forming diastereomeric solvates in solution that can generate nonequivalences in the NMR spectra of enantiomerically enriched mixtures. As a result, differentiation of enantiomers is observed, thus allowing the quantification of the enantiomeric composition of the mixture under investigation. The tendency of certain substrates to self-aggregate and to generate diastereomeric adducts in solution can be defined as Self-Induced Diastereomeric Anisochrony (SIDA), but other acronyms have been used to refer to this phenomenon. In the present work, an overview of SIDA processes investigated via NMR spectroscopy will be provided, with a particular emphasis on the nature of the substrates involved, on the interaction mechanisms at the basis of the phenomenon, and on theoretical treatments proposed in the literature to explain them.
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Affiliation(s)
- Federica Aiello
- National Research Council, Institute for Chemical and Physical Processes (CNR-IPCF), Via G. Moruzzi 1, 56124 Pisa, Italy
| | - Gloria Uccello Barretta
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy; (F.B.); (F.S.)
| | - Federica Balzano
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy; (F.B.); (F.S.)
| | - Fabio Spiaggia
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy; (F.B.); (F.S.)
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2
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Hu S. Copper (II) Ions Induced Self-Disproportionation of Enantiomers in Capillary Electrophoresis for the Quantification of Atenolol Enantiomers. Molecules 2023; 28:5908. [PMID: 37570878 PMCID: PMC10420844 DOI: 10.3390/molecules28155908] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 08/13/2023] Open
Abstract
Despite the fact that the self-disproportionation of enantiomers (SDE) has been found for several decades and has been widely used in crystallization, sublimation and chromatography for the purification or separation of nonracemic compounds, the phenomenon of SDE in capillary electrophoresis (CE) has never been reported up to now. Here, a new approach to separate enantiomers in CE based on SDE was demonstrated by introducing copper (II) ions into the separation media. The enantiomers of atenolol interact with copper ions to produce positively charged complexes with different electrophoretic mobilities from the single molecules. The dynamic equilibrium between homo- or heterochiral complexes (associates) and single molecules of atenolol enantiomers supports the manifestation of SDE. Different mobilities of the single molecules and associates, and different distribution of two enantiomers between the single molecules and associates caused by their different concentrations, produce a net difference in electrodriven migration velocities of the two enantiomers. The relative movement of two enantiomers causes a zone depleted in one enantiomer at the rear end of sample segment, giving a trapezoidal CE curve with a step at the end. Quantification of enantiomers is achieved according to the step height. The analysis does not rely on the use of enantiomerically pure chiral selector and the result agrees with that obtained by conventional chiral CE using a chiral selector.
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Affiliation(s)
- Shaoqiang Hu
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471934, China
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3
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Olbrycht M, Gumieniak J, Mruc P, Balawejder M, Piątkowski W, Antos D. Separation of non-racemic mixtures of enantiomers by achiral chromatography. J Chromatogr A 2023; 1693:463877. [PMID: 36854210 DOI: 10.1016/j.chroma.2023.463877] [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: 01/10/2023] [Revised: 02/15/2023] [Accepted: 02/15/2023] [Indexed: 02/21/2023]
Abstract
The phenomenon of partial separation of enantiomeric mixtures in achiral chromatography (ACh) has already been documented for a wide variety of chiral compounds. It is attributed to the so-called effect of self-disproportionation of enantiomers (SDE). However, quantitative description of the SDE mechanism underlying adsorption of enantiomers on achiral surfaces is still incomplete, which hinders the application of that technique for large-scale separations. In this study, a mechanistic model for description of retention behavior of SDE-phoric compounds in silica-based ACh has been developed along with a procedure for fast determination of the model parameters. The model assumes formation of associates of chiral molecules, which occurs due to homo and hetero-chiral interactions in the adsorbed phase. The ability of the model to reproduce band profiles was verified for enantiomeric mixtures of three structurally different chiral compounds.
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Affiliation(s)
- Maksymilian Olbrycht
- Department of Chemical and Process Engineering, Rzeszow University of Technology, Rzeszów, Poland
| | - Justyna Gumieniak
- Department of Component Manufacturing and Production Organization, Rzeszów University of Technology, Stalowa Wola, Poland
| | - Patrycja Mruc
- Doctoral School of Engineering and Technical Sciences at the Rzeszów University of Technology, Poland
| | - Maciej Balawejder
- Institute of Food Technology and Nutrition, The College of Natural Sciences, University of Rzeszów, Rzeszów, Poland
| | - Wojciech Piątkowski
- Department of Chemical and Process Engineering, Rzeszow University of Technology, Rzeszów, Poland
| | - Dorota Antos
- Department of Chemical and Process Engineering, Rzeszow University of Technology, Rzeszów, Poland.
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4
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Dašková V, Padín D, Feringa BL. Turning Enantiomeric Relationships into Diastereomeric Ones: Self-Resolving α-Ureidophosphonates and Their Organocatalytic Enantioselective Synthesis. J Am Chem Soc 2022; 144:23603-23613. [PMID: 36516975 PMCID: PMC9801384 DOI: 10.1021/jacs.2c10911] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Controlling chiral recognition and chiral information transfer has major implications in areas ranging from drug design and asymmetric catalysis to supra- and macromolecular chemistry. Especially intriguing are phenomena associated with chiral self-recognition. The design of systems that show self-induced recognition of enantiomers, i.e., involving homochiral versus heterochiral dimers, is particularly challenging. Here, we report the chiral self-recognition of α-ureidophosphonates and its application as both a powerful analytical tool for enantiomeric ratio determination by NMR and as a convenient way to increase their enantiomeric purity by simple achiral column chromatography or fractional precipitation. A combination of NMR, X-ray, and DFT studies indicates that the formation of homo- and heterochiral dimers involving self-complementary intermolecular hydrogen bonds is responsible for their self-resolving properties. It is also shown that these often unnoticed chiral recognition phenomena can facilitate the stereochemical analysis during the development of new asymmetric transformations. As a proof of concept, the enantioselective organocatalytic hydrophosphonylation of alkylidene ureas toward self-resolving α-ureidophosphonates is presented, which also led us to the discovery of the largest family of self-resolving compounds reported to date.
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5
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Peluso P, Chankvetadze B. Recognition in the Domain of Molecular Chirality: From Noncovalent Interactions to Separation of Enantiomers. Chem Rev 2022; 122:13235-13400. [PMID: 35917234 DOI: 10.1021/acs.chemrev.1c00846] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
It is not a coincidence that both chirality and noncovalent interactions are ubiquitous in nature and synthetic molecular systems. Noncovalent interactivity between chiral molecules underlies enantioselective recognition as a fundamental phenomenon regulating life and human activities. Thus, noncovalent interactions represent the narrative thread of a fascinating story which goes across several disciplines of medical, chemical, physical, biological, and other natural sciences. This review has been conceived with the awareness that a modern attitude toward molecular chirality and its consequences needs to be founded on multidisciplinary approaches to disclose the molecular basis of essential enantioselective phenomena in the domain of chemical, physical, and life sciences. With the primary aim of discussing this topic in an integrated way, a comprehensive pool of rational and systematic multidisciplinary information is provided, which concerns the fundamentals of chirality, a description of noncovalent interactions, and their implications in enantioselective processes occurring in different contexts. A specific focus is devoted to enantioselection in chromatography and electromigration techniques because of their unique feature as "multistep" processes. A second motivation for writing this review is to make a clear statement about the state of the art, the tools we have at our disposal, and what is still missing to fully understand the mechanisms underlying enantioselective recognition.
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Affiliation(s)
- Paola Peluso
- Istituto di Chimica Biomolecolare ICB, CNR, Sede secondaria di Sassari, Traversa La Crucca 3, Regione Baldinca, Li Punti, I-07100 Sassari, Italy
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Avenue 3, 0179 Tbilisi, Georgia
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6
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Han J, Wzorek A, Klika KD, Soloshonok VA. Recommended Tests for the Self-Disproportionation of Enantiomers (SDE) to Ensure Accurate Reporting of the Stereochemical Outcome of Enantioselective Reactions. MOLECULES (BASEL, SWITZERLAND) 2021; 26:molecules26092757. [PMID: 34067099 PMCID: PMC8124418 DOI: 10.3390/molecules26092757] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 05/04/2021] [Accepted: 05/04/2021] [Indexed: 12/14/2022]
Abstract
The purpose of this review is to highlight the necessity of conducting tests to gauge the magnitude of the self-disproportionation of enantiomers (SDE) phenomenon to ensure the veracity of reported enantiomeric excess (ee) values for scalemic samples obtained from enantioselective reactions, natural products isolation, etc. The SDE always occurs to some degree whenever any scalemic sample is subjected to physicochemical processes concomitant with the fractionation of the sample, thus leading to erroneous reporting of the true ee of the sample if due care is not taken to either preclude the effects of the SDE by measurement of the ee prior to the application of physicochemical processes, suppressing the SDE, or evaluating all obtained fractions of the sample. Or even avoiding fractionation altogether if possible. There is a clear necessity to conduct tests to assess the magnitude of the SDE for the processes applied to samples and the updated and improved recommendations described herein cover chromatography and processes involving gas-phase transformations such as evaporation or sublimation.
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Affiliation(s)
- Jianlin Han
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China;
| | - Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland;
| | - Karel D. Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- Correspondence: (K.D.K.); (V.A.S.)
| | - Vadim A. Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, Alameda Urquijo 36-5, Plaza Bizkaia, 48011 Bilbao, Spain
- Correspondence: (K.D.K.); (V.A.S.)
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Flurbiprofen: A Study of the Behavior of the Scalemate by Chromatography, Sublimation, and NMR. Symmetry (Basel) 2021. [DOI: 10.3390/sym13040543] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
2-(2-Fluoro-4-biphenyl) propionic acid (flurbiprofen), from the phenylalkanoic acid family of nonsteroidal anti-inflammatory drugs (NSAID’s), is currently on the pharmaceutical market as a racemate. This racemic compound was tested for its propensity to undergo the self-disproportionation of enantiomers (SDE) phenomenon by various forms of chromatography (SDEvC), such as routine gravity-driven column chromatography, medium-pressure liquid chromatography (MPLC), preparative thin-layer chromatography (PTLC), and size-exclusion chromatography (SEC), as well as by sublimation (SDEvS). Furthermore, examination by nuclear magnetic resonance (NMR) in various solvents found that flurbiprofen exhibited the phenomenon of self-induced diastereomeric anisochronism (SIDA). By measurement of the diffusion coefficient (D), the longitudinal relaxation time (T1), and the transverse relaxation time (T2) using NMR, as well as by electrospray ionization-mass spectrometry (ESI-MS) examinations, the preferred intermolecular association was found to be solvent dependent, e.g., heterochiral association was preferred in toluene, while homochiral association was preferred in more polar solvents. This study also attempted, unsuccessfully, to correlate the NMR measurements of flurbiprofen with chromatographic outcomes for the rationalization and prediction of chromatographic results based on NMR measurements. Because the intermolecular hydrogen bonding of the acid groups in flurbiprofen overwhelmingly predominates over other intermolecular interactions, flurbiprofen seemed to represent a good test case for this idea. The behavior of scalemic samples of flurbiprofen is important, as, although it is currently dispensed as a racemate, clinical applications of the R enantiomer have been investigated. SDEvC and SDEvS both have ramifications for the preparation, handling, and storage of enantioenriched flurbiprofen, and this concern applies to other chiral drugs as well.
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8
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Potentially Mistaking Enantiomers for Different Compounds Due to the Self-Induced Diastereomeric Anisochronism (SIDA) Phenomenon. Symmetry (Basel) 2020. [DOI: 10.3390/sym12071106] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The NMR phenomenon of self-induced diastereomeric anisochronism (SIDA) was observed with an alcohol and an ester. The alcohol exhibited large concentration-dependent chemical shifts (δ’s), which initially led us to erroneously consider whether two enantiomers were in fact atropisomers. This highlights a potential complication for the analysis of chiral compounds due to SIDA, namely the misidentification of enantiomers. A heterochiral association preference for the alcohol in CDCl3 was determined by the intermolecular nuclear Overhauser effect (NOE) and diffusion measurements, the same preference as found in the solid state. The ester revealed more subtle effects, but concentration-dependent δ’s, observation of intermolecular NOE’s, as well as distinct signals for the two enantiomers in a scalemic sample all indicated the formation of associates. Intermolecular NOE and diffusion measurements indicated that homochiral association is slightly preferred over heterochiral association in CDCl3, thus masking association for enantiopure and racemic samples of equal concentration. As observed with the alcohol, heterochiral association was preferred for the ester in the solid state. The potential problems that SIDA can cause are highlighted and constitute a warning: Due care should be taken with respect to conditions, particularly the concentration, when measuring NMR spectra of chiral compounds. Scalemic samples of both the alcohol and the ester were found to exhibit the self-disproportionation of enantiomers (SDE) phenomenon by preparative TLC, the first report of SDE by preparative TLC.
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9
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Kwiatkowska M, Marcinkowska M, Wzorek A, Pajkert R, Han J, Klika KD, Soloshonok VA, Röschenthaler GV. The self-disproportionation of enantiomers (SDE) via column chromatography of β-amino-α,α-difluorophosphonic acid derivatives. Amino Acids 2019; 51:1377-1385. [PMID: 31468209 DOI: 10.1007/s00726-019-02774-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 08/18/2019] [Indexed: 01/05/2023]
Abstract
This work presents the first study of the self-disproportionation of enantiomers via chromatography (SDEvC) of β-aminophosphonic acid esters, several of which have been synthesized for the first time. Three types of structures were examined, N-acetylated, dipeptide construction with N-Cbz glycine, and a free amine. In the latter case, this is the first time that SDEvC has been reported for free amine amino acids. In all the three types of structures, significant SDE magnitudes (Δee's up to 55%) were exhibited underscoring the ubiquitous nature of the SDE phenomenon. Chemical models of homo- versus heterochiral intermolecular interactions are proposed to rationalize the SDE magnitude differences amongst these new β-aminophosphonic acid derivatives. In addition, the incorporation of additional, competing binding modes to a molecule, was found to lead to a reduction of the SDE magnitude by shifting the intermolecular binding away from the stereogenic center and/or by leading to a convoluted binding system that disrupts the structured and relatively stable assemblies that give rise to the SDE.
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Affiliation(s)
- Magdalena Kwiatkowska
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland
| | - Magdalena Marcinkowska
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland
| | - Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland.
| | - Romana Pajkert
- Department of Life Sciences and Chemistry, Jacobs University Bremen gGmbH, 28759, Bremen, Germany
| | - Jianlin Han
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China.
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain. .,IKERBASQUE, Basque Foundation for Science, María Díaz de Haro 3, Plaza Bizkaia, 48013, Bilbao, Spain.
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10
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Han J, Wzorek A, Soloshonok VA, Klika KD. The self-disproportionation of enantiomers (SDE): The effect of scaling down, potential problems versus prospective applications, possible new occurrences, and unrealized opportunities? Electrophoresis 2019; 40:1869-1880. [PMID: 30653701 DOI: 10.1002/elps.201800414] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 12/24/2018] [Accepted: 01/13/2019] [Indexed: 11/10/2022]
Abstract
This commentary discusses an important, though not widely appreciated, chiral phenomenon of molecular chirality that effectively always occurs whenever nonracemic samples are subjected to practically any physicochemical process (e.g., force field, recrystallization, sublimation, even distillation, etc.) under totally achiral conditions external to the sample itself. The phenomenon is termed as the self-disproportionation of enantiomers (SDE) and though ubiquitous, its presence may not always be readily apparent, or workers may be otherwise oblivious to its effects. In the particular case of chromatography, when the SDE is apparent, the enantiomeric excess (ee) of the chiral compound is observed to vary across an eluted peak, with anterior eluted portions either enantioenriched or enantiodepleted relative to the ee of the starting material, and conversely for the posterior eluted portions. Herein, we highlight various aspects of the SDE phenomenon as it pertains to chromatography and, in particular, the effect of scaling down chromatographic systems, the potential risk of problems that the SDE can cause, as well as opportunities for practical applications of the phenomenon, possible new occurrences of the SDE phenomenon to be searched for, and unrealized opportunities.
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Affiliation(s)
- Jianlin Han
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, P. R. China
| | - Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Kielce, Poland.,Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, San Sebastián, Spain
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, San Sebastián, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Heidelberg, Germany
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11
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Self-induced recognition of enantiomers (SIRE) and its application in chiral NMR analysis. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2018.07.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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12
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Han J, Kitagawa O, Wzorek A, Klika KD, Soloshonok VA. The self-disproportionation of enantiomers (SDE): a menace or an opportunity? Chem Sci 2018; 9:1718-1739. [PMID: 29675218 PMCID: PMC5892310 DOI: 10.1039/c7sc05138g] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 01/12/2018] [Indexed: 01/05/2023] Open
Abstract
Herein we report on the well-documented, yet not widely known, phenomenon of the self-disproportionation of enantiomers (SDE): the spontaneous fractionation of scalemic material into enantioenriched and -depleted fractions when any physicochemical process is applied.
Herein we report on the well-documented, yet not widely known, phenomenon of the self-disproportionation of enantiomers (SDE): the spontaneous fractionation of scalemic material into enantioenriched and -depleted fractions when any physicochemical process is applied. The SDE has implications ranging from the origins of prebiotic homochirality to unconventional enantiopurification methods, though the risks of altering the enantiomeric excess (ee) unintentionally, regrettably, remain greatly unappreciated. While recrystallization is well known as an SDE process, occurrences of the SDE in other processes are much less recognized, e.g. sublimation and even distillation. But the most common process that many workers seem to be completely ignorant of is SDE via chromatography and reports have included all manner of structures, all types of interactions, and all forms of chromatography, including GC. The SDE can be either a blessing – as a means to obtain enantiopure samples from scalemates – or a curse, as unwitting alteration of the ee leads to errors in the reporting of results and/or misinterpretation of the system under study. Thus the ramifications of the SDE are relevant to any area involving chirality – natural products, asymmetric synthesis, etc. Moreover, there is grave concern regarding errors in the literature, in addition to the possible occurrence of valid results which may have been overlooked and thus remain unreported, as well as the potential for the SDE to alter the ee, particularly via chromatography, and the following concepts will be conveyed: (1) the SDE occurs under totally achiral conditions of (a) precipitation, (b) centrifugation, (c) evaporation, (d) distillation, (e) crystallization, (f) sublimation, and (g) achiral chromatography (e.g. column, flash, MPLC, HPLC, SEC, GC, etc.). (2) The SDE cannot be controlled simply by experimental accuracy and ignorance of the SDE unavoidably leads to mistakes in the recorded and reported stereochemical outcome of enantioselective transformations. (3) The magnitude of the SDE (the difference between the extremes of enantioenrichment and -depletion) can be controlled and used to: (a) minimize mistakes in the recorded experimental values and (b) to develop unconventional and preparatively superior methods for enantiopurification. (4) The magnitude of the SDE cannot be predicted but can be expected for compounds possessing SDE-phoric groups or which have a general tendency for strong hydrogen or halogen bonds or dipole–dipole or aromatic π–π interactions. (5) An SDE test and the rigorous reporting and description of applied physicochemical processes should become part of standard experimental practice to prevent the erroneous reporting of the stereochemical outcome of enantioselective catalytic reactions and the chirooptical properties of scalemates. New directions in the study of the SDE, including halogen bonding-based interactions and novel, unconventional enantiopurification methods such as pseudo-SDE (chiral selector-assisted SDE resolution of racemates), are also reported.
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Affiliation(s)
- Jianlin Han
- School of Chemistry and Chemical Engineering , State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Nanjing University , 210093 Nanjing , China .
| | - Osamu Kitagawa
- Department of Applied Chemistry , Shibaura Institute of Technology , 3-7-5 Toyosu, Kohto-ku , Tokyo 135-8548 , Japan
| | - Alicja Wzorek
- Institute of Chemistry , Jan Kochanowski University in Kielce , Świętokrzyska 15G , 25-406 Kielce , Poland.,Department of Organic Chemistry I , Faculty of Chemistry , University of the Basque Country UPV/EHU , Paseo Manuel Lardizábal 3 , 20018 San Sebastián , Spain .
| | - Karel D Klika
- Molecular Structure Analysis , German Cancer Research Center (DKFZ) , Im Neuenheimer Feld 280 , D-69009 Heidelberg , Germany .
| | - Vadim A Soloshonok
- Department of Organic Chemistry I , Faculty of Chemistry , University of the Basque Country UPV/EHU , Paseo Manuel Lardizábal 3 , 20018 San Sebastián , Spain . .,IKERBASQUE, Basque Foundation for Science , Alameda Urquijo 36-5, Plaza, Bizkaia , 48011 Bilbao , Spain
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13
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Han J, Soloshonok VA, Klika KD, Drabowicz J, Wzorek A. Chiral sulfoxides: advances in asymmetric synthesis and problems with the accurate determination of the stereochemical outcome. Chem Soc Rev 2017; 47:1307-1350. [PMID: 29271432 DOI: 10.1039/c6cs00703a] [Citation(s) in RCA: 162] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Chiral sulfoxides are in extremely high demand in nearly every sector of the chemical industry concerned with the design and development of new synthetic reagents, drugs, and functional materials. The primary objective of this review is to update readers on the latest developments from the past five years (2011-2016) in the preparation of optically active sulfoxides. Methodologies covered include catalytic asymmetric sulfoxidation using either chemical, enzymatic, or hybrid biocatalytic means; kinetic resolution involving oxidation to sulfones, reduction to sulfides, modification of side chains, and imidation to sulfoximines; as well as various other methods including nucleophilic displacement at the sulfur atom for the desymmetrization of achiral sulfoxides, enantioselective recognition and separation based on either metal-organic frameworks (MOF's) or host-guest chemistry, and the Horner-Wadsworth-Emmons reaction. A second goal of this work concerns a critical discussion of the problem of the accurate determination of the stereochemical outcome of a reaction due to the self-disproportionation of enantiomers (SDE) phenomenon, particularly as it relates to chiral sulfoxides. The SDE is a little-appreciated phenomenon that can readily and spontaneously occur for scalemic samples when subjected to practically any physicochemical process. It has now been unequivocally demonstrated that ignorance in the SDE phenomenon inevitably leads to erroneous interpretation of the stereochemical outcome of catalytic enantioselective reactions, in particular, for the synthesis of chiral sulfoxides. It is hoped that this two-pronged approach to covering the chemistry of chiral sulfoxides will be appealing, engaging, and motivating for current research-active authors to respond to in their future publications in this exciting area of current research.
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Affiliation(s)
- Jianlin Han
- School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Nanjing University, 210093 Nanjing, China.
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018 San Sebastián, Spain. and IKERBASQUE, Basque Foundation for Science, Alameda Urquijo 36-5, Plaza Bizkaia, 48011 Bilbao, Spain
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69009 Heidelberg, Germany.
| | - Józef Drabowicz
- Department of Heterooganic Chemistry, Center of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łódź, Poland and Institute of Chemistry, Environmental Protection and Biotechnology, Jan Długosz University in Częstochowa, Armii Krajowej 13/15, 42-201 Częstochowa, Poland
| | - Alicja Wzorek
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018 San Sebastián, Spain. and Institute of Chemistry, Jan Kochanowski University in Kielce, Swiętokrzyska 15G, 25-406 Kielce, Poland.
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14
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A question of policy: should tests for the self-disproportionation of enantiomers (SDE) be mandatory for reports involving scalemates? ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.tetasy.2017.08.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Terada S, Hirai M, Honzawa A, Kitagawa O, Kamizela A, Wzorek A, Soloshonok VA. Possible Case of Halogen Bond-Driven Self-Disproportionation of Enantiomers (SDE) via Achiral Chromatography. Chemistry 2017; 23:14631-14638. [PMID: 28783208 DOI: 10.1002/chem.201703308] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Indexed: 11/12/2022]
Abstract
The major breakthrough reported in this work is the discovery of likely halogen bond-driven self-disproportionation of enantiomers (SDE). Taking into account that the halogen-bonding interactions can be rationally designed and can match, or even exceed, the strength of the more familiar hydrogen bond, this discovery clearly opens an unexpected new direction of research in the areas of molecular chirality and the SDE phenomenon.
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Affiliation(s)
- Shumpei Terada
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Motohiro Hirai
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Ayaka Honzawa
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Osamu Kitagawa
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Angelika Kamizela
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland
| | - Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland.,Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain.,JKERBASQUE, Basque Foundation for Science, University of the Basque Country UPV/EHU, Maria Diaz de Haro 3, 48013, Bilbao, Spain
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16
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Martens J, Bhushan R. Enantioseparations in Achiral Environments and Chromatographic Systems. Isr J Chem 2016. [DOI: 10.1002/ijch.201600086] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jürgen Martens
- Institute of Chemistry; Carl von Ossietzky University Oldenburg; Carl-von-Ossietzky-Strasse 9-11, DE- 26129 Oldenburg Germany
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17
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Wzorek A, Sato A, Drabowicz J, Soloshonok VA, Klika KD. Remarkable magnitude of the self-disproportionation of enantiomers (SDE) via achiral chromatography: application to the practical-scale enantiopurification of β-amino acid esters. Amino Acids 2015; 48:605-13. [PMID: 26704565 DOI: 10.1007/s00726-015-2152-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/08/2015] [Indexed: 11/28/2022]
Abstract
We report the best performance yet for the self-disproportionation of enantiomers (SDE) via achiral chromatography as typically used in laboratories for the isolated yield of the excess enantiomer using N-acetyl β-amino acid ethyl esters. The results are the most convincing ever demonstration of the capability of the SDE for practical-scale enantiopurification as comparable, or even superior for some systems, to that of recrystallization. For example, from a sample of 94.4 % ee, a yield of 71 % of enantiopure material was isolated in a single chromatographic run. Moreover, the lack of an esoteric structural entity, e.g. strongly polarizing groups, such as, for instance CF3, highlights the fact that the phenomenon is not dependent on the presence of such and thus the process is relevant to any usual-type structure. In contrast to recrystallization, the procedure is predictable, general, and dependable, boding well for its widespread application in routine laboratory settings.
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Affiliation(s)
- Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland. .,Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain.
| | - Azusa Sato
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain.,Department of Chemistry, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666, Japan
| | - Józef Drabowicz
- Department of Heteroorganic Chemistry, Center of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363, Łódź, Poland.,Institute of Chemistry, Environmental Protection and Biotechnology, Jan Dlugosz University in Czestochowa, Armii Krajowej 13/15, 42-201, Częstochowa, Poland
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain. .,IKERBASQUE, Basque Foundation for Science, Alameda Urquijo 36-5, Plaza Bizkaia, 48011, Bilbao, Spain.
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69009, Heidelberg, Germany.
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18
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Wzorek A, Klika KD, Drabowicz J, Sato A, Aceña JL, Soloshonok VA. The self-disproportionation of the enantiomers (SDE) of methyl n-pentyl sulfoxide via achiral, gravity-driven column chromatography: a case study. Org Biomol Chem 2015; 12:4738-46. [PMID: 24873904 DOI: 10.1039/c4ob00831f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work explores the self-disproportionation of enantiomers (SDE) of chiral sulfoxides via achiral, gravity-driven column chromatography using methyl n-pentyl sulfoxide as a case study. A major finding of this work is the remarkable persistence and high magnitude of the SDE for the analyte. Thus, it is the first case where SDE is observed even in the presence of MeOH in the mobile phase. The study demonstrated the practical preparation, in line with theory, of enantiomerically pure (>99.9% ee) samples of methyl n-pentyl sulfoxide starting from a sample of only modest ee (<35%). Remarkably, it was found that the order of elution was inverted, i.e. enantiomerically depleted fractions preceded later eluting enantiomerically enriched ones, when the stationary phase was changed from silica gel to aluminum oxide. To the best of our knowledge, this is the first occurrence of inverted SDE behavior due solely to a change in the stationary phase. Aberrant SDE behavior was observed in that the ee did not always fall continuously during the progression of the chromatography, and this was attributed to the complexity of the system at hand which cannot be described in simple terms such as the formation only of homo- and heterochiral dimers based on a single interaction. The results nevertheless suggest that all compounds with a chiral sulfoxide moiety in their structure are likely to exhibit the SDE phenomenon and thus this work constitutes the first example of SDE predictability. Moreover, it could well be that optical purification based on the SDE phenomenon is a simple, convenient, and inexpensive method for the optical purification of this class of compounds with a high degree of proficiency.
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Affiliation(s)
- Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Swiętokrzyska 15G, 25-406 Kielce, Poland
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19
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Wzorek A, Sato A, Drabowicz J, Soloshonok VA, Klika KD. Enantiomeric Enrichmentsviathe Self-Disproportionation of Enantiomers (SDE) by Achiral, Gravity-Driven Column Chromatography: a Case Study UsingN-(1-Phenylethyl)acetamide for Optimizing the Enantiomerically Pure Yield and Magnitude of the SDE. Helv Chim Acta 2015. [DOI: 10.1002/hlca.201500041] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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20
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Han J, Aceña JL, Yasuda N, Uekusa H, Ono T, Soloshonok VA, Klika KD. Carbonyl group coordination preferences in square-planar NiII and PdII complexes of pentadentate ligands by electron-withdrawing/donating substituents. Inorganica Chim Acta 2015. [DOI: 10.1016/j.ica.2015.04.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Xu Z, Wang Q, Zhu J. Total Syntheses of (-)-Mersicarpine, (-)-Scholarisine G, (+)-Melodinine E, (-)-Leuconoxine, (-)-Leuconolam, (-)-Leuconodine A, (+)-Leuconodine F, and (-)-Leuconodine C: Self-Induced Diastereomeric Anisochronism (SIDA) Phenomenon for Scholarisine G and Leuconodines A and C. J Am Chem Soc 2015; 137:6712-24. [PMID: 25946614 DOI: 10.1021/jacs.5b03619] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Enantioselective total syntheses of title natural products from a common cyclohexenone derivative (S)-18 were reported. Ozonolysis of (S)-18 afforded a stable diketo ester (R)-17 that was subsequently converted to two skeletally different natural products, i.e., (-)-mersicarpine (8) with a [6.5.6.7] fused tetracyclic ring system and (-)-scholarisine G (9) with a [6.5.6.6.5] fused pentacyclic skeleton, respectively. The postcyclization diversification was realized by taking advantage of the facile conversion of (+)-melodinine E (6) to N-acyliminium ion 7, from which a hydroxy group was selectively introduced to the C6, C7, C10 and the central C21 position of diazafenestrane system, leading to (-)-leuconodine A (11), (+)-leuconodine F (12), (-)-scholarisine G (9), (-)-leuconodine C (13), and skeletally different (-)-leuconolam (5). Furthermore, an unprecedented non-natural oxabridged oxadiazafenestrane 68 was formed by oxidation of (+)-melodinine E (6). During the course of this study, a strong self-induced diastereomeric anisochronism (SIDA) phenomenon was observed for scholarisine G (9), leuconodines A (11) and C (13). X-ray structures of both the racemic and the enantiopure natural products 9, 11, and 13 were obtained. The different crystal packing of these two forms nicely explained the chemical shift differences observed in the (1)H NMR spectra of the racemic and the enantio-enriched compounds in an achiral environment.
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Affiliation(s)
- Zhengren Xu
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, CH-1015 Lausanne, Switzerland
| | - Qian Wang
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, CH-1015 Lausanne, Switzerland
| | - Jieping Zhu
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, CH-1015 Lausanne, Switzerland
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22
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Maeno M, Tokunaga E, Yamamoto T, Suzuki T, Ogino Y, Ito E, Shiro M, Asahi T, Shibata N. Self-disproportionation of enantiomers of thalidomide and its fluorinated analogue via gravity-driven achiral chromatography: mechanistic rationale and implications. Chem Sci 2015; 6:1043-1048. [PMID: 29560192 PMCID: PMC5811091 DOI: 10.1039/c4sc03047h] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 10/30/2014] [Indexed: 01/13/2023] Open
Abstract
We report on the self-disproportionation of enantiomers (SDE) of non-racemic thalidomide (1) and 3'-fluorothalidomide (2) under the conditions of gravity-driven achiral silica-gel chromatography. The presence of a fluorine atom on the chiral center dramatically alters the structure and polarity of 1 and 2, resulting in the opposite SDE profile on silica-gel.
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Affiliation(s)
- Mayaka Maeno
- Department of Nanopharmaceutical Sciences and Department of Frontier Materials , Nagoya Institute of Technology , Gokiso, Showa-ku , Nagoya 466-8555 , Japan .
| | - Etsuko Tokunaga
- Department of Nanopharmaceutical Sciences and Department of Frontier Materials , Nagoya Institute of Technology , Gokiso, Showa-ku , Nagoya 466-8555 , Japan .
| | - Takeshi Yamamoto
- Department of Nanopharmaceutical Sciences and Department of Frontier Materials , Nagoya Institute of Technology , Gokiso, Showa-ku , Nagoya 466-8555 , Japan .
| | - Toshiya Suzuki
- Department of Life Science and Medical Bioscience , Waseda University (TWIns) , Wakamatsu-cho 2-2, Shinjuku-ku , Tokyo 162-8480 , Japan .
| | - Yoshiyuki Ogino
- Department of Life Science and Medical Bioscience , Waseda University (TWIns) , Wakamatsu-cho 2-2, Shinjuku-ku , Tokyo 162-8480 , Japan .
| | - Emi Ito
- Department of Nanopharmaceutical Sciences and Department of Frontier Materials , Nagoya Institute of Technology , Gokiso, Showa-ku , Nagoya 466-8555 , Japan .
| | - Motoo Shiro
- Consolidated Research Institute for Advanced Science and Medical Care , Waseda University (ASMeW) , Waseda-tsurumaki-cho 513, Shinjuku-ku , Tokyo 162-0041 , Japan
| | - Toru Asahi
- Department of Life Science and Medical Bioscience , Waseda University (TWIns) , Wakamatsu-cho 2-2, Shinjuku-ku , Tokyo 162-8480 , Japan .
| | - Norio Shibata
- Department of Nanopharmaceutical Sciences and Department of Frontier Materials , Nagoya Institute of Technology , Gokiso, Showa-ku , Nagoya 466-8555 , Japan .
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23
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Suzuki Y, Han J, Kitagawa O, Aceña JL, Klika KD, Soloshonok VA. A comprehensive examination of the self-disproportionation of enantiomers (SDE) of chiral amides via achiral, laboratory-routine, gravity-driven column chromatography. RSC Adv 2015. [DOI: 10.1039/c4ra13928c] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The behavior of a series of chiral amides during column chromatography using an achiral stationary phase revealed that a self-disproportionation of enantiomers (SDE) was always observed regardless of amide structure or chromatographic conditions.
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Affiliation(s)
- Yuya Suzuki
- Department of Applied Chemistry
- Shibaura Institute of Technology
- Tokyo 135-8548
- Japan
| | - Jianlin Han
- School of Chemistry and Chemical Engineering
- Nanjing University
- 210093 Nanjing
- China
| | - Osamu Kitagawa
- Department of Applied Chemistry
- Shibaura Institute of Technology
- Tokyo 135-8548
- Japan
| | - José Luis Aceña
- Department of Organic Chemistry I
- Faculty of Chemistry
- University of the Basque Country UPV/EHU
- 20018 San Sebastián
- Spain
| | - Karel D. Klika
- Molecular Structure Analysis
- German Cancer Research Center (DKFZ)
- D-69009 Heidelberg
- Germany
| | - Vadim A. Soloshonok
- Department of Organic Chemistry I
- Faculty of Chemistry
- University of the Basque Country UPV/EHU
- 20018 San Sebastián
- Spain
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24
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25
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26
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A three-component protocol for the enantiodifferentiation of amines using triphenyl borate and BINOL: is it an ion pair or an amine-coordinated complex? ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.tetasy.2014.03.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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27
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Martens J, Bhushan R. Purification of Enantiomeric Mixtures in Enantioselective Synthesis: Overlooked Errors and Scientific Basis of Separation in Achiral Environment. Helv Chim Acta 2014. [DOI: 10.1002/hlca.201300392] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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28
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Han J, Ono T, Uekusa H, Klika KD, Soloshonok VA. Substituent-controlled preference of carbonyl group–metal coordination in d8 metal complexes with non-symmetric pentadentate ligands. Structural and stereochemical aspects. Dalton Trans 2014; 43:5375-81. [DOI: 10.1039/c3dt53312c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The sidearm substitution of chirally switchable Ni(ii) and Pd(ii) complexes permits stereochemical inclinations to be controlled in the solid state.
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Affiliation(s)
- Jianlin Han
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing, China
| | - Taizo Ono
- National Institute of Advanced Industrial Science and Technology (AIST)
- Nagoya, Japan
| | - Hidehiro Uekusa
- Department of Chemistry and Materials Science
- Tokyo Institute of Technology
- Tokyo 152-8551, Japan
| | - Karel D. Klika
- Molecular Structure Analysis
- German Cancer Research Center (DKFZ)
- D-69009 Heidelberg, Germany
- Department of Chemistry
- University of Turku
| | - Vadim A. Soloshonok
- Department of Organic Chemistry I
- Faculty of Chemistry
- University of the Basque Country UPV/EHU
- 20018 San Sebastián, Spain
- IKERBASQUE
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29
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Sorochinsky AE, Katagiri T, Ono T, Wzorek A, Aceña JL, Soloshonok VA. Optical purifications via self-disproportionation of enantiomers by achiral chromatography: case study of a series of α-CF3-containing secondary alcohols. Chirality 2013; 25:365-8. [PMID: 23716267 DOI: 10.1002/chir.22180] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 03/19/2013] [Accepted: 03/20/2013] [Indexed: 11/10/2022]
Abstract
This work demonstrates that self-disproportionation of enantiomers via achiral chromatography can be recommended as inexpensive and general method for optical purification of enantiomerically enriched compounds. In particular, the advantage of this approach over conventional recrystallization is that it can be used for both crystalline as well as liquid compounds.
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Affiliation(s)
- Alexander E Sorochinsky
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, San Sebastián, Spain
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30
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Self-disproportionation of enantiomers of prazoles via achiral, gravity-driven silica gel column chromatography. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.tetasy.2013.06.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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31
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Trapp O, Schurig V. Nonlinear effects in enantioselective chromatography: prediction of unusual elution profiles of enantiomers in non-racemic mixtures on an achiral stationary phase doped with small amounts of a chiral selector. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.tetasy.2010.04.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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32
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Klika KD, Budovská M, Kutschy P. NMR spectral enantioresolution of spirobrassinin and 1-methoxyspirobrassinin enantiomers using (S)-(−)-ethyl lactate and modeling of spirobrassinin self-association for rationalization of its self-induced diastereomeric anisochromism (SIDA) and enantiomer self-disproportionation on achiral-phase chromatography (ESDAC) phenomena. J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2009.10.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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33
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34
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Enantiodifferentiation of phytoalexin spirobrassinin derivatives using the chiral solvating agent (R)-(+)-1,1′-bi-2-naphthol in conjunction with molecular modeling. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.tetasy.2010.03.035] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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35
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36
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Self-disproportionation of enantiomers of heterocyclic compounds having a tertiary trifluoromethyl alcohol center on chromatography with a non-chiral system. J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2009.12.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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37
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Albrecht M, Soloshonok VA, Schrader L, Yasumoto M, Suhm MA. Chirality-dependent sublimation of -(trifluoromethyl)-lactic acid: Relative vapor pressures of racemic, eutectic, and enantiomerically pure forms, and vibrational spectroscopy of isolated (S,S) and (S,R) dimers. J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2009.11.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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38
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Yasumoto M, Ueki H, Ono T, Katagiri T, Soloshonok VA. Self-disproportionation of enantiomers of isopropyl 3,3,3-(trifluoro)lactate via sublimation: Sublimation rates vs. enantiomeric composition. J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2009.11.026] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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39
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First principle lattice energy calculations for enantiopure and racemic crystals of α-(trifluoromethyl)lactic acid: Is self-disproportionation of enantiomers controlled by thermodynamic stability of crystals? J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2009.12.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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40
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Yasumoto M, Ueki H, Soloshonok VA. Self-disproportionation of enantiomers of 3,3,3-trifluorolactic acid amides via sublimation. J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2009.10.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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41
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Klika KD, Kramer M, Kleinpeter E. DFT computational studies of hydrogen bonding-based diastereomeric complexes – Limitations and applications to enantiodifferentiation. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.theochem.2009.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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42
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Klika KD. Use of sub-stoichiometric amounts of chiral auxiliaries for enantiodifferentiation by NMR; caveats and potential utility. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.tetasy.2009.03.036] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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