1
|
Schmahl S, Horn F, Jin J, Westphal H, Belder D, Asmis KR. Online-Monitoring of the Enantiomeric Ratio in Microfluidic Chip Reactors Using Chiral Selector Ion Vibrational Spectroscopy. Chemphyschem 2024; 25:e202300975. [PMID: 38418402 DOI: 10.1002/cphc.202300975] [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: 12/18/2023] [Revised: 02/23/2024] [Accepted: 02/23/2024] [Indexed: 03/01/2024]
Abstract
A novel experimental approach for the rapid online monitoring of the enantiomeric ratio of chiral analytes in solution is presented. The charged analyte is transferred to the gas phase by electrospray. Diastereomeric complexes are formed with a volatile chiral selector in a buffer-gas-filled ion guide held at room temperature, mass-selected, and subsequently spectrally differentiated by cryogenic ion trap vibrational spectroscopy. Based on the spectra of the pure complexes in a small diastereomer-specific spectral range, the composition of diastereomeric mixtures is characterized using the cosine similarity score, from which the enantiomeric ratio in the solution is determined. The method is demonstrated for acidified alanine solutions and using three different chiral selectors (2-butanol, 1-phenylethanol, 1-amino-2-propanol). Among these, 2-butanol is the best choice as a selector for protonated alanine, also because the formation ratio of the corresponding diastereomeric complexes is found to be independent of the nature of the enantiomer. Subsequently, a microfluidic chip is implemented to mix enantiomerically pure alanine solutions continuously and determine the enantiomeric ratio online with minimal sample consumption within one minute and with competitive accuracy.
Collapse
Affiliation(s)
- Sonja Schmahl
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103, Leipzig, Germany
| | - Francine Horn
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103, Leipzig, Germany
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195, Berlin, Germany
| | - Jiaye Jin
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103, Leipzig, Germany
| | - Hannes Westphal
- Institut für Analytische Chemie, Universität Leipzig, Linnéstraße 3, 04103, Leipzig, Germany
| | - Detlev Belder
- Institut für Analytische Chemie, Universität Leipzig, Linnéstraße 3, 04103, Leipzig, Germany
| | - Knut R Asmis
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103, Leipzig, Germany
| |
Collapse
|
2
|
Xu J, Bakker JM, Lushchikova OV, Lievens P, Janssens E, Hou GL. Pentagon, Hexagon, or Bridge? Identifying the Location of a Single Vanadium Cation on Buckminsterfullerene Surface. J Am Chem Soc 2023; 145:22243-22251. [PMID: 37757468 DOI: 10.1021/jacs.3c08451] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
Buckminsterfullerene C60 has received extensive research interest since its discovery. In addition to its interesting intrinsic properties of exceptional stability and electron-accepting ability, the broad chemical tunability by decoration or substitution on the C60-fullerene surface makes it a fascinating molecule. However, to date, there is uncertainty about the binding location of such decorations on the C60 surface, even for a single adsorbed metal atom. In this work, we report the gas-phase synthesis of the C60V+ complex and its in situ characterization by mass spectrometry and infrared spectroscopy with the help of quantum chemical calculations and molecular dynamics simulations. We identify the most probable binding position of a vanadium cation on C60 above a pentagon center in an η5-fashion, demonstrate a high thermal stability for this complex, and explore the bonding nature between C60 and the vanadium cation, revealing that large orbital and electrostatic interactions lie at the origin of the stability of the η5-C60V+ complex.
Collapse
Affiliation(s)
- Jianzhi Xu
- MOE Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed Matter, School of Physics, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Joost M Bakker
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, HFML-FELIX, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Olga V Lushchikova
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, HFML-FELIX, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Peter Lievens
- Quantum Solid-State Physics, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
| | - Ewald Janssens
- Quantum Solid-State Physics, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
| | - Gao-Lei Hou
- MOE Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed Matter, School of Physics, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| |
Collapse
|
3
|
Li YK, Müller F, Schöllkopf W, Asmis KR, Sauer J. Gas-Phase Mechanism of O .- /Ni 2+ -Mediated Methane Conversion to Formaldehyde. Angew Chem Int Ed Engl 2022; 61:e202202297. [PMID: 35460320 PMCID: PMC9400983 DOI: 10.1002/anie.202202297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Indexed: 01/05/2023]
Abstract
The gas-phase reaction of NiAl2 O4 + with CH4 is studied by mass spectrometry in combination with vibrational action spectroscopy and density functional theory (DFT). Two product ions, NiAl2 O4 H+ and NiAl2 O3 H2 + , are identified in the mass spectra. The DFT calculations predict that the global minimum-energy isomer of NiAl2 O4 + contains Ni in the +II oxidation state and features a terminal Al-O.- oxygen radical site. They show that methane can react along two competing pathways leading to formation of either a methyl radical (CH3 ⋅) or formaldehyde (CH2 O). Both reactions are initiated by hydrogen atom transfer from methane to the terminal O.- site, followed by either CH3 ⋅ loss or CH3 ⋅ migration to an O2- site next to the Ni2+ center. The CH3 ⋅ attaches as CH3 + to O2- and its unpaired electron is transferred to the Ni-center reducing it to Ni+ . The proposed mechanism is experimentally confirmed by vibrational spectroscopy of the reactant and two different product ions.
Collapse
Affiliation(s)
- Ya-Ke Li
- Wilhelm-Ostwald Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany.,Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195, Berlin, Germany.,Present address: Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China
| | - Fabian Müller
- Wilhelm-Ostwald Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany.,Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195, Berlin, Germany.,Institut für Chemie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany
| | - Wieland Schöllkopf
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195, Berlin, Germany
| | - Knut R Asmis
- Wilhelm-Ostwald Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany
| | - Joachim Sauer
- Institut für Chemie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany
| |
Collapse
|
4
|
Li Y, Müller F, Schöllkopf W, Asmis KR, Sauer J. Gas‐Phase Mechanism of O
.−
/Ni
2+
‐Mediated Methane Conversion to Formaldehyde. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202202297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ya‐Ke Li
- Wilhelm-Ostwald Institut für Physikalische und Theoretische Chemie Universität Leipzig Linnéstr. 2 04103 Leipzig Germany
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Germany
- Present address: Green Catalysis Center and College of Chemistry Zhengzhou University Zhengzhou 450001 China
| | - Fabian Müller
- Wilhelm-Ostwald Institut für Physikalische und Theoretische Chemie Universität Leipzig Linnéstr. 2 04103 Leipzig Germany
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Germany
- Institut für Chemie Humboldt-Universität zu Berlin Unter den Linden 6 10099 Berlin Germany
| | - Wieland Schöllkopf
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6 14195 Berlin Germany
| | - Knut R. Asmis
- Wilhelm-Ostwald Institut für Physikalische und Theoretische Chemie Universität Leipzig Linnéstr. 2 04103 Leipzig Germany
| | - Joachim Sauer
- Institut für Chemie Humboldt-Universität zu Berlin Unter den Linden 6 10099 Berlin Germany
| |
Collapse
|
5
|
Müller F, Sauer J, Song X, Asmis KR. The Chemical Nature of Ti 4O 10-: Vibrational Predissociation Spectroscopy Combined with Global Structure Optimization. J Phys Chem A 2021; 125:9571-9577. [PMID: 34709822 DOI: 10.1021/acs.jpca.1c05552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The gas-phase infrared spectrum of Ti4O10- is studied in the spectral range from 400 cm-1 to 1250 cm-1 using cryogenic ion trap vibrational spectroscopy, in combination with density functional theory (DFT). The infrared photodissociation (IRPD) spectrum of D2-tagged Ti4O10- provides evidence for a structure of lower symmetry that contains a superoxo group (1121 cm-1) and two terminal Ti=O moieties. DFT combined with a genetic algorithm for global structure optimization predicts two isomers which feature a superoxo group: the Cs symmetric global minimum-energy structure and a similar isomer (C1) that is slightly higher in energy. Coupled cluster calculations confirm the relative stability. Comparison of the harmonic DFT spectra (different functionals) with the IRPD spectrum suggests that both of these isomers contribute. Earlier assignments to the adamantane-like C3v isomer with three terminal Ti-O• - groups in a quartet state are not confirmed. They were based on the infrared multiple photon photodissociation (IRMPD) spectrum of bare Ti4O10- and local DFT structure optimizations.
Collapse
Affiliation(s)
- Fabian Müller
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstr. 2, 04103 Leipzig, Germany.,Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Joachim Sauer
- Institut für Chemie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099 Berlin, Germany
| | - Xiaowei Song
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Knut R Asmis
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstr. 2, 04103 Leipzig, Germany
| |
Collapse
|
6
|
Li YK, Babin MC, Debnath S, Iwasa T, Kumar S, Taketsugu T, Asmis KR, Lyalin A, Neumark DM. Structural Characterization of Nickel-Doped Aluminum Oxide Cations by Cryogenic Ion Trap Vibrational Spectroscopy. J Phys Chem A 2021; 125:9527-9535. [PMID: 34693712 DOI: 10.1021/acs.jpca.1c07156] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Isolated nickel-doped aluminum oxide cations (NiOm)(Al2O3)n(AlO)+ with m = 1-2 and n = 1-3 are investigated by infrared photodissociation (IRPD) spectroscopy in combination with density functional theory and the single-component artificial force-induced reaction method. IRPD spectra of the corresponding He-tagged cations are reported in the 400-1200 cm-1 spectral range and assigned based on a comparison to calculated harmonic IR spectra of low-energy isomers. Simulated spectra of the lowest energy structures generally match the experimental spectra, but multiple isomers may contribute to the spectra of the m = 2 series. The identified structures of the oxides (m = 1) correspond to inserting a Ni-O moiety into an Al-O bond of the corresponding (Al2O3)1-3(AlO)+ cluster, yielding either a doubly or triply coordinated Ni2+ center. The m = 2 clusters prefer similar structures in which the additional O atom either is incorporated into a peroxide unit, leaving the oxidation state of the Ni2+ atom unchanged, or forms a biradical comprising a terminal oxygen radical anion Al-O•- and a Ni3+ species. These clusters represent model systems for under-coordinated Ni sites in alumina-supported Ni catalysts and should prove helpful in disentangling the mechanism of selective oxidative dehydrogenation of alkanes by Ni-doped catalysts.
Collapse
Affiliation(s)
- Ya-Ke Li
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstrasse 2, 04103 Leipzig, Germany.,Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Mark C Babin
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Sreekanta Debnath
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstrasse 2, 04103 Leipzig, Germany.,Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Takeshi Iwasa
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Sonu Kumar
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
| | - Tetsuya Taketsugu
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.,Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
| | - Knut R Asmis
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstrasse 2, 04103 Leipzig, Germany
| | - Andrey Lyalin
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan.,Center for Green Research on Energy and Environmental Materials, National Institute for Material Science (NIMS), Tsukuba 305-0044, Japan
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| |
Collapse
|
7
|
Affiliation(s)
- Martin Mayer
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103 Leipzig, Germany
| | - Knut R. Asmis
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103 Leipzig, Germany
| |
Collapse
|
8
|
Berenbeim JA, Wong NGK, Cockett MCR, Berden G, Oomens J, Rijs AM, Dessent CEH. Sodium cationization can disrupt the intramolecular hydrogen bond that mediates the sunscreen activity of oxybenzone. Phys Chem Chem Phys 2020; 22:19522-19531. [PMID: 32840272 DOI: 10.1039/d0cp03152f] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A key decay pathway by which organic sunscreen molecules dissipate harmful UV energy involves excited-state hydrogen atom transfer between proximal enol and keto functional groups. Structural modifications of this molecular architecture have the potential to block ultrafast decay processes, and hence promote direct excited-state molecular dissociation, profoundly affecting the efficiency of an organic sunscreen. Herein, we investigate the binding of alkali metal cations to a prototype organic sunscreen molecule, oxybenzone, using IR characterization. Mass-selective IR action spectroscopy was conducted at the free electron laser for infrared experiments, FELIX (600-1800 cm-1), on complexes of Na+, K+ and Rb+ bound to oxybenzone. The IR spectra reveal that K+ and Rb+ adopt binding positions away from the key OH intermolecular hydrogen bond, while the smaller Na+ cation binds directly between the keto and enol oxygens, thus breaking the intramolecular hydrogen bond. UV laser photodissociation spectroscopy was also performed on the series of complexes, with the Na+ complex displaying a distinctive electronic spectrum compared to those of K+ and Rb+, in line with the IR spectroscopy results. TD-DFT calculations reveal that the origin of the changes in the electronic spectra can be linked to rupture of the intramolecular bond in the sodium cationized complex. The implications of our results for the performance of sunscreens in mixtures and environments with high concentrations of metal cations are discussed.
Collapse
Affiliation(s)
- Jacob A Berenbeim
- Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
| | - Natalie G K Wong
- Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
| | - Martin C R Cockett
- Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
| | - Giel Berden
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, Nijmegen, The Netherlands
| | - Jos Oomens
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, Nijmegen, The Netherlands
| | - Anouk M Rijs
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7, Nijmegen, The Netherlands
| | | |
Collapse
|
9
|
Mayer M, Pahl M, Spanka M, Grellmann M, Sickert M, Schneider C, Asmis KR, Belder D. Unravelling the configuration of transient ortho-quinone methides by combining microfluidics with gas phase vibrational spectroscopy. Phys Chem Chem Phys 2020; 22:4610-4616. [DOI: 10.1039/c9cp06435d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The alkylidene double bond configuration of transient ortho-quinone methides (o-QMs) is studied by cryogenic ion trap vibrational spectroscopy.
Collapse
Affiliation(s)
- Martin Mayer
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie
- Universität Leipzig
- D-04103 Leipzig
- Germany
| | - Maik Pahl
- Institut für Analytische Chemie
- Universität Leipzig
- D-04103 Leipzig
- Germany
| | - Matthias Spanka
- Institut für Organische Chemie
- Universität Leipzig
- D-04103 Leipzig
- Germany
| | - Max Grellmann
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie
- Universität Leipzig
- D-04103 Leipzig
- Germany
| | - Marcel Sickert
- Institut für Organische Chemie
- Universität Leipzig
- D-04103 Leipzig
- Germany
| | | | - Knut R. Asmis
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie
- Universität Leipzig
- D-04103 Leipzig
- Germany
| | - Detlev Belder
- Institut für Analytische Chemie
- Universität Leipzig
- D-04103 Leipzig
- Germany
| |
Collapse
|
10
|
Carrà A, Macaluso V, Villalta PW, Spezia R, Balbo S. Fragmentation Spectra Prediction and DNA Adducts Structural Determination. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:2771-2784. [PMID: 31696434 DOI: 10.1007/s13361-019-02348-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/04/2019] [Accepted: 10/09/2019] [Indexed: 06/10/2023]
Abstract
In this work, chemical dynamics simulations were optimized and used to predict fragmentation mass spectra for DNA adduct structural determination. O6-methylguanine (O6-Me-G) was used as a simple model adduct to calculate theoretical spectra for comparison with measured high-resolution fragmentation data. An automatic protocol was established to consider the different tautomers accessible at a given energy and obtain final theoretical spectra by insertion of an initial tautomer. In the work reported here, the most stable tautomer was chosen as the initial structure, but in general, any structure could be considered. Allowing for the formation of the various possible tautomers during simulation calculations was found to be important to getting a more complete fragmentation spectrum. The calculated theoretical results reproduce the experimental peaks such that it was possible to determine reaction pathways and product structures. The calculated tautomerization network was crucial to correctly identifying all the observed ion peaks, showing that a mobile proton model holds not only for peptide fragmentation but also for nucleobases. Finally, first principles results were compared to simple machine learning fragmentation models.
Collapse
Affiliation(s)
- Andrea Carrà
- Masonic Cancer Center, University of Minnesota, 2231 6th Street SE, Minneapolis, MN, 55455, USA
| | - Veronica Macaluso
- Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement, Université d'Evry, CEA, CNRS, Université Paris Saclay, Bd. F. Mitterrand, 91025, Evry Cedex, France
| | - Peter W Villalta
- Masonic Cancer Center, University of Minnesota, 2231 6th Street SE, Minneapolis, MN, 55455, USA
| | - Riccardo Spezia
- Laboratoire de Chimie Théorique, LCT, CNRS, Sorbonne Université, F. 75005, Paris, France.
| | - Silvia Balbo
- Masonic Cancer Center, University of Minnesota, 2231 6th Street SE, Minneapolis, MN, 55455, USA.
| |
Collapse
|