1
|
Reversible nucleophilic addition can lower the observed enantioselectivity in palladium-catalyzed allylic amination reactions with a variety of chiral ligands. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.08.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
2
|
Keller BO, Esbata AA, Buncel E, van Loon GW. Rapidly formed quinalphos complexes with transition metal ions characterized by electrospray ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:1319-1328. [PMID: 23681809 DOI: 10.1002/rcm.6570] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 02/07/2013] [Accepted: 02/08/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE Electrospray ionization tandem mass spectrometry (ESI-MS/MS) offers the unique opportunity to characterize complexes of the organophosphorus pesticide (OP) quinalphos (PA-Q) with transition metal ions immediately formed after contact. This study complements research looking at longer term kinetics of quinalphos hydrolysis in the presence of transition metal ions and gives insights into the structural features of the initial complex formation in solution. (Hydrolysis reaction: PA-Q + H2 O → PA-OH + HQ, where PA-OH is the diethyl phosphate product and HQ is hydroxyquinoxaline.) METHODS Low micromolar PA-Q solutions with an approximately 3-fold molar excess of transition metal ions were immediately analyzed after mixing. Fragmentation of the transition metal ion complexes with PA-Q was accomplished in two different ways: first, in-source fragmentation by elevating the declustering potential and second, low-energy collision-induced dissociation (CID). RESULTS For Ag(+), the [PA-Q - Ag(+)] and respective Ag(+) -containing degradation product ions are readily observed. For Cu(2+), we observed the [PA-Q + Cu(2+) + NO3(-)] complex ion with weak intensity and strong signals from both the [2PA-Q + Cu(+)] and the [PA-Q + Cu(+)] ions, the latter two attributable to charge-state reduction in the gas phase from Cu(II) to Cu(I), indicating that PA-Q fulfills specific structural requirements of the formed complex for charge-state reduction during transition from solution to the gas phase. For Hg(2+), the [PA-Q + Hg(2+) + (PA-OH - H)(-)] ion was the largest observed species containing one Hg(2+) ion. No 1:1 species ([PA-Q] or other degradation products:Hg(2+)) was observable. CONCLUSIONS ESI-MS/MS of complexes formed from PA-Q and transition metal ions is a formidable technique to probe initial formation of these complexes in solution. Previous work from other groups established structural requirements that enable charge-state reduction from Cu(II) to Cu(I) in ligand complexes during transition into the gas phase, and these rules allow us to propose structural features of PA-Q complexes with copper ions in solution.
Collapse
Affiliation(s)
- Bernd O Keller
- Department of Pathology & Laboratory Medicine, University of British Columbia, Child & Family Research Institute, Vancouver, BC, V5Z 4H4, Canada.
| | | | | | | |
Collapse
|
3
|
Schröder D. Applications of electrospray ionization mass spectrometry in mechanistic studies and catalysis research. Acc Chem Res 2012; 45:1521-32. [PMID: 22702223 DOI: 10.1021/ar3000426] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mechanistic studies form the basis for a better understanding of chemical processes, helping researchers develop more sustainable reactions by increasing the yields of the desired products, reducing waste production, and lowering the consumption of resources and energy overall. Conventional methods for the investigation of reaction mechanisms in solution include kinetic studies, isotope labeling, trapping of reactive intermediates, and advanced spectroscopic techniques. Within the past decade, electrospray ionization mass spectrometry (ESI-MS) has provided an additional tool for mechanistic studies because researchers can directly probe liquid samples by mass spectrometry under gentle conditions. Specifically, ESI-MS allows researchers to identify the molecular entities present in solution over the course of a chemical transformation. ESI-MS is particularly useful for investigations of organic reactions or metal catalysis that involve ionic intermediates. Accordingly, researchers are increasingly using ESI-MS in mechanistic studies and catalyst development. However, a further understanding of the ESI process and how it can facilitate mechanistic studies has not accompanied this increased use of the technique. Therefore, at least in part the ESI-MS method not only has offered great promise for the elucidation of reaction mechanisms but also became a black box with the occasional risk of misinterpretation. In this Account, we summarize applications of ESI-MS for synthetic and mechanistic research. Recently researchers have established direct linkages between gas-phase data obtained via ESI-MS and processes occurring in solution, and these results reveal qualitative and quantitative correlations between ESI-MS measurements and solution properties. In this context, time dependences, concentration series, and counterion effects can serve as criteria that allow researchers assess if the gas-phase measurements correlate with the situation in the solution. Furthermore, we report developments that bridge the gap between gas-phase and solution-phase studies. We also describe predictions derived from ESI-MS that have been verified with solution-phase chemistry experiments.
Collapse
Affiliation(s)
- Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| |
Collapse
|
4
|
Schröder D, Buděšínský M, Roithová J. Deprotonation of p-Hydroxybenzoic Acid: Does Electrospray Ionization Sample Solution or Gas-Phase Structures? J Am Chem Soc 2012; 134:15897-905. [DOI: 10.1021/ja3060589] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2,
16610 Prague 6, Czech Republic
| | - Miloš Buděšínský
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2,
16610 Prague 6, Czech Republic
| | - Jana Roithová
- Department of Organic Chemistry,
Faculty of Sciences, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic
| |
Collapse
|
5
|
Severa L, Jirásek M, Švec P, Teplý F, Révész Á, Schröder D, Koval D, Kašička V, Císařová I, Šaman D. Counterion-Induced Inversion of Conformer Stability of a [5]Helquat Dication. Chempluschem 2012. [DOI: 10.1002/cplu.201200009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
6
|
Jaklová Dytrtová J, Jakl M, Schröder D. Complexation of malic acid with cadmium(II) probed by electrospray ionization mass spectrometry. Talanta 2012; 90:63-8. [DOI: 10.1016/j.talanta.2011.12.076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 12/24/2011] [Accepted: 12/28/2011] [Indexed: 11/26/2022]
|
7
|
|
8
|
Schröder D. Ion clustering in electrospray mass spectrometry of brine and other electrolyte solutions. Phys Chem Chem Phys 2012; 14:6382-90. [DOI: 10.1039/c2cp40586e] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
9
|
Révész Á, Schröder D, Svec J, Wimmerová M, Sindelar V. Anion Binding by Bambus[6]uril Probed in the Gas Phase and in Solution. J Phys Chem A 2011; 115:11378-86. [DOI: 10.1021/jp205218k] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Ágnes Révész
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | | | | | | |
Collapse
|
10
|
Agrawal D, Schröder D, Frech CM. Observation of Binuclear Palladium Clusters upon ESI-MS Monitoring of the Suzuki–Miyaura Cross-Coupling Catalyzed by a Dichloro-bis(aminophosphine) Complex of Palladium. Organometallics 2011. [DOI: 10.1021/om200274z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Divya Agrawal
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 16610 Prague 6, Czech Republic
| | - Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 16610 Prague 6, Czech Republic
| | - Christian M. Frech
- Institute of Inorganic Chemistry, University of Zürich, Winterthurstrasse 190, 8057 Zürich, Switzerland
| |
Collapse
|
11
|
Dytrtová JJ, Jakl M, Schröder D, Čadková E, Komárek M. Complexation between the fungicide tebuconazole and copper(II) probed by electrospray ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:1037-1042. [PMID: 21452380 DOI: 10.1002/rcm.4957] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 01/21/2011] [Accepted: 01/23/2011] [Indexed: 05/30/2023]
Abstract
Electrospray ionization mass spectrometry (ESI-MS) is used to probe the complex formation between tebuconazole (1) and copper(II) salts, which both are commonly used fungicides in agriculture. Experiments with model solutions containing 1 and CuCl(2) reveal the initial formation of the copper(II) species [(1)CuCl](+) and [(1)(2)CuCl](+) which undergo reduction to the corresponding copper(I) ions [(1)Cu](+) and [(1)(2)Cu](+) under more drastic ionization conditions in the ESI source. In additional experiments, copper/tebuconazole complexes were also detected in samples made from soil solutions of various origin and different amount of mineralization. The direct sampling of such solutions via ESI-MS is thus potentially useful for understanding of the interactions between copper(II) salts and tebuconazole in environmental samples.
Collapse
Affiliation(s)
- Jana Jaklová Dytrtová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo náměstí 2, 166 10, Prague 6, Czech Republic.
| | | | | | | | | |
Collapse
|
12
|
Paterová J, Heyda J, Jungwirth P, Shaffer CJ, Révész Á, Zins EL, Schröder D. Microhydration of the Magnesium(II) Acetate Cation in the Gas Phase. J Phys Chem A 2011; 115:6813-9. [DOI: 10.1021/jp110463b] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Jana Paterová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Jan Heyda
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Christopher J. Shaffer
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Ágnes Révész
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Emilie L. Zins
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| |
Collapse
|
13
|
Butschke B, Schwarz H. Thermal C−H Bond Activation of Benzene, Toluene, and Methane with Cationic [M(X)(bipy)]+ (M = Ni, Pd, Pt; X = CH3, Cl; bipy = 2,2′-bipyridine): A Mechanistic Study. Organometallics 2011. [DOI: 10.1021/om101138d] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Burkhard Butschke
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, D-10623 Berlin, Germany
| | - Helmut Schwarz
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, D-10623 Berlin, Germany
| |
Collapse
|
14
|
Schröder D, Ducháčková L, Tarábek J, Karwowska M, Fijalkowski KJ, Ončák M, Slavíček P. Direct Observation of Triple Ions in Aqueous Solutions of Nickel(II) Sulfate: A Molecular Link Between the Gas Phase and Bulk Behavior. J Am Chem Soc 2011; 133:2444-51. [DOI: 10.1021/ja105408a] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, v.v.i., Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Lucie Ducháčková
- Department of Organic and Nuclear Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic
| | - Ján Tarábek
- Institute of Organic Chemistry and Biochemistry, v.v.i., Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | | | | | - Milan Ončák
- Institute of Chemical Technology Prague, Technická 5, 16628 Prague 6, Czech Republic
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 18223 Prague 8, Czech Republic
| | - Petr Slavíček
- Institute of Chemical Technology Prague, Technická 5, 16628 Prague 6, Czech Republic
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 18223 Prague 8, Czech Republic
| |
Collapse
|
15
|
Agrawal D, Schröder D. Insight into Solution Chemistry from Gas-Phase Experiments. Organometallics 2011. [DOI: 10.1021/om100972n] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Divya Agrawal
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| | - Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| |
Collapse
|
16
|
Ducháčková L, Roithová J, Milko P, Žabka J, Tsierkezos N, Schröder D. Comparative Study of Mono- and Dinuclear Complexes of Late 3d-Metal Chlorides with N,N-Dimethylformamide in the Gas phase. Inorg Chem 2010; 50:771-82. [DOI: 10.1021/ic100759h] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lucie Ducháčková
- Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic
| | - Jana Roithová
- Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic
| | - Petr Milko
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
- Institute of Chemistry and the Lise-Meitner-Minerva Center for Computational Quantum Chemistry, Hebrew University of Jerusalem, 91904, Jerusalem, Israel
| | - Jan Žabka
- J. Heyrovský Institute of Physical Chemistry, Dolejškova, 3, 18223 Prague 8, Czech Republic
| | - Nikos Tsierkezos
- Institut für Chemie, Elektrochemie und Galvanotechnik, Technische Universität Ilmenau, Weimarer Strasse 25, 98693 Ilmenau, Germany
| | - Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| |
Collapse
|