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Yang M, Xiong Z, Li Y, Chen X, Zhou W. Gas-phase formation of Grignard-type organolanthanide (III) ions RLnCl 3 - : The influences of lanthanide center and hydrocarbyl group. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2023; 37:e9512. [PMID: 36972406 DOI: 10.1002/rcm.9512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/17/2023] [Accepted: 03/20/2023] [Indexed: 05/16/2023]
Abstract
RATIONALE Compared with organomagnesium compounds (Grignard reagents), the Grignard-type organolanthanides (III) exhibit several utilizable differences in reactivity. However, the fundamental understanding of Grignard-type organolanthanides (III) is still in its infancy. Decarboxylation of metal carboxylate ions is an effective method to obtain organometallic ions that are well suited for gas-phase investigation using electrospray ionization (ESI) mass spectrometry in combination with density functional theory (DFT) calculations. METHODS The (RCO2 )LnCl3 - (R = CH3 , Ln = La-Lu except Pm; Ln = La, R = CH3 CH2 , CH2 CH, HCC, C6 H5 , and C6 H11 ) precursor ions were produced in the gas phase via ESI of LnCl3 and RCO2 H or RCO2 Na mixtures in methanol. Collision-induced dissociation (CID) was employed to examine whether the Grignard-type organolanthanide (III) ions RLnCl3 - can be obtained via decarboxylation of lanthanide chloride carboxylate ions (RCO2 )LnCl3 - . DFT calculations can be used to determine the influences of lanthanide center and hydrocarbyl group on the formation of RLnCl3 - . RESULTS When R = CH3 , CID of (CH3 CO2 )LnCl3 - (Ln = La-Lu except Pm) yielded decarboxylation products (CH3 )LnCl3 - and reduction products LnCl3 ·- with a variation in the relative intensity ratio of (CH3 )LnCl3 - /LnCl3 ·- . The trend is as follows: (CH3 )EuCl3 - /EuCl3 ·- < (CH3 )YbCl3 - /YbCl3 ·- ≈ (CH3 )SmCl3 - /SmCl3 ·- < other (CH3 )LnCl3 - /LnCl3 ·- , which complies with the trend of Ln (III)/Ln (II) reduction potentials in general. When Ln = La and hydrocarbyl groups were varied as CH3 CH2 , CH2 CH, HCC, C6 H5 , and C6 H11 , the fragmentation behaviors of these (RCO2 )LaCl3 - precursor ions were diverse. Except for (C6 H11 CO2 )LaCl3 - , the four remaining (RCO2 )LaCl3 - (R = CH3 CH2 , CH2 CH, HCC, and C6 H5 ) ions all underwent decarboxylation to yield RLaCl3 - . (CH2 CH)LaCl3 - and especially (CH3 CH2 )LaCl3 - are prone to undergo β-hydride transfer to form LaHCl3 - , whereas (HCC)LaCl3 - and (C6 H5 )LaCl3 - are not. A minor reduction product, LaCl3 ·- , was formed via C6 H5 radical loss of (C6 H5 )LaCl3 - . The relative intensities of RLaCl3 - compared to (RCO2 )LaCl3 - decrease as follows: HCC > CH2 CH > C6 H5 > CH3 > CH3 CH2 >> C6 H11 (not visible). CONCLUSION A series of Grignard-type organolanthanide (III) ions RLnCl3 - (R = CH3 , Ln = La-Lu except Pm; Ln = La, R = CH3 CH2 , CH2 CH, HCC, and C6 H5 ) were produced from (RCO2 )LnCl3 - via CO2 loss, whereas (C6 H11 )LaCl3 - did not. The experimental and theoretical results suggest that the reduction potentials of Ln (III)/Ln (II) couples as well as the bulkiness and hybridization of hydrocarbyl groups play important roles in promoting or limiting the formation of RLnCl3 - via decarboxylation of (RCO2 )LnCl3 - .
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Affiliation(s)
- Meixian Yang
- Department of Radiochemistry, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
- School of Chemical Sciences, School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Zhixin Xiong
- Department of Radiochemistry, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
- School of Chemical Sciences, School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Yangjuan Li
- Department of Radiochemistry, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
| | - Xiuting Chen
- Department of Radiochemistry, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
| | - Wei Zhou
- Department of Radiochemistry, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
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Jin Q, Li J, Ariafard A, Canty AJ, O'Hair RA. Formation and reactions of the 1, 8-naphthyridine (napy) ligated geminally dimetallated phenyl complexes [(napy)Cu 2(Ph)] +, [(napy)Ag 2(Ph)] + and [(napy)CuAg(Ph)] . EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2019; 25:30-43. [PMID: 30773925 DOI: 10.1177/1469066718795959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Gas-phase ion trap mass spectrometry experiments and density functional theory calculations have been used to examine the routes to the formation of the 1,8-naphthyridine (napy) ligated geminally dimetallated phenyl complexes [(napy)Cu2(Ph)]+, [(napy)Ag2(Ph)]+ and [(napy)CuAg(Ph)]+ via extrusion of CO2 or SO2 under collision-induced dissociation conditions from their corresponding precursor complexes [(napy)Cu2(O2CPh)]+, [(napy)Ag2(O2CPh)]+, [(napy)CuAg(O2CPh)]+ and [(napy)Cu2(O2SPh)]+, [(napy)Ag2(O2SPh)]+, [(napy)CuAg(O2SPh)]+. Desulfination was found to be more facile than decarboxylation. Density functional theory calculations reveal that extrusion proceeds via two transition states: TS1 enables isomerization of the O, O-bridged benzoate to its O-bound form; TS2 involves extrusion of CO2 or SO2 with the concomitant formation of the organometallic cation and has the highest barrier. Of all the organometallic cations, only [(napy)Cu2(Ph)]+ reacts with water via hydrolysis to give [(napy)Cu2(OH)]+, consistent with density functional theory calculations which show that hydrolysis proceeds via the initial formation of the adduct [(napy)Cu2(Ph)(H2O)]+ which then proceeds via TS3 in which the coordinated H2O is deprotonated by the coordinated phenyl anion to give the product complex [(napy)Cu2(OH)(C6H6)]+, which then loses benzene.
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Affiliation(s)
- Qiuyan Jin
- 1 School of Chemistry and Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Victoria, Australia
| | - Jiaye Li
- 1 School of Chemistry and Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Victoria, Australia
| | - Alireza Ariafard
- 2 Department of Chemistry, Faculty of Science, Central Tehran Branch, Islamic Azad University, Shahrak Gharb, Tehran, Iran
| | - Allan J Canty
- 3 School of Physical Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Richard Aj O'Hair
- 1 School of Chemistry and Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Victoria, Australia
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3
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Cheng GJ, Zhong XM, Wu YD, Zhang X. Mechanistic understanding of catalysis by combining mass spectrometry and computation. Chem Commun (Camb) 2019; 55:12749-12764. [PMID: 31560354 DOI: 10.1039/c9cc05458h] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The combination of mass spectrometry and computational chemistry has been proven to be powerful for exploring reaction mechanisms. The former provides information of reaction intermediates, while the latter gives detailed reaction energy profiles.
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Affiliation(s)
- Gui-Juan Cheng
- Lab of Computational Chemistry and Drug Design
- State Key Laboratory of Chemical Oncogenomics
- Peking University Shenzhen Graduate School
- Shenzhen
- China
| | - Xiu-Mei Zhong
- Lab of Computational Chemistry and Drug Design
- State Key Laboratory of Chemical Oncogenomics
- Peking University Shenzhen Graduate School
- Shenzhen
- China
| | - Yun-Dong Wu
- Lab of Computational Chemistry and Drug Design
- State Key Laboratory of Chemical Oncogenomics
- Peking University Shenzhen Graduate School
- Shenzhen
- China
| | - Xinhao Zhang
- Lab of Computational Chemistry and Drug Design
- State Key Laboratory of Chemical Oncogenomics
- Peking University Shenzhen Graduate School
- Shenzhen
- China
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4
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Bathie FLB, Bowen CJ, Hutton CA, O'Hair RAJ. Unimolecular reactivity of organotrifluoroborate anions, RBF 3- , and their alkali metal cluster ions, M(RBF 3 ) 2- (M = Na, K; R = CH 3 , CH 3 CH 2 , CH 3 (CH 2 ) 3 , CH 3 (CH 2 ) 5 , c-C 3 H 5 , C 6 H 5 , C 6 H 5 CH 2 , CH 2 CHCH 2 , CH 2 CH, C 6 H 5 CO). RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2018; 32:1045-1052. [PMID: 29645303 DOI: 10.1002/rcm.8134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/22/2018] [Accepted: 03/25/2018] [Indexed: 06/08/2023]
Abstract
RATIONALE Potassium organotrifluoroborates (RBF3 K) are important reagents used in organic synthesis. Although mass spectrometry is commonly used to confirm their molecular formulae, the gas-phase fragmentation reactions of organotrifluoroborates and their alkali metal cluster ions have not been previously reported. METHODS Negative-ion mode electrospray ionization (ESI) together with collision-induced dissociation (CID) using a triple quadrupole mass spectrometer were used to examine the fragmentation pathways for RBF3- (where R = CH3 , CH3 CH2 , CH3 (CH2 )3 , CH3 (CH2 )5 , c-C3 H5 , C6 H5 , C6 H5 CH2 , CH2 CHCH2 , CH2 CH, C6 H5 CO) and M(RBF3 )2- (M = Na, K), while density functional theory (DFT) calculations at the M06/def2-TZVP level were used to examine the structures and energies associated with fragmentation reactions for R = Me and Ph. RESULTS Upon CID, preferentially elimination of HF occurs for RBF3- ions for systems where R = an alkyl anion, whereas R- formation is favoured when R = a stabilized anion. At higher collision energies loss of F- and additional HF losses are sometimes observed. Upon CID of M(RBF3 )2- , formation of RBF3- is the preferred pathway with some fluoride transfer observed only when M = Na. The DFT-calculated relative thermochemistry for competing fragmentation pathways is consistent with the experiments. CONCLUSIONS The main fragmentation pathways of RBF3- are HF elimination and/or R- loss. This contrasts with the fragmentation reactions of other organometallate anions, where reductive elimination, beta hydride transfer and bond homolysis are often observed. The presence of fluoride transfer upon CID of Na(RBF3 )2- but not K(RBF3 )2- is in agreement with the known fluoride affinities of Na+ and K+ and can be rationalized by Pearson's HSAB theory.
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Affiliation(s)
- Fiona L B Bathie
- School of Chemistry and Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Chris J Bowen
- Shimadzu Scientific, Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Craig A Hutton
- School of Chemistry and Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Richard A J O'Hair
- School of Chemistry and Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Parkville, Victoria, 3010, Australia
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5
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Do dihydroxymagnesium carboxylates form Grignard-type reagents? A theoretical investigation on decarboxylative fragmentation. J Mol Model 2018; 24:106. [PMID: 29589173 DOI: 10.1007/s00894-018-3639-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 03/12/2018] [Indexed: 10/17/2022]
Abstract
Dihydroxymagnesium carboxylates [(OH)2MgO2CR] were probed for decarboxylation on a theoretical level, by utilizing both Møller-Plesset perturbation theory (MP2) and density functional theory (B3LYP-DFT) computations. This study is connected to the question of whether this recently introduced, astrobiologically relevant chemical class may form Grignard-type reagent molecules. To extract trends for a broad molecular mass range, different linear alkyl chain lengths between C4 and C11 were computed. The forward energy barrier for decarboxylation reactions increases linearly as a function of the ligand's chain length. Decarboxylation-type fragmentations of these organomagnesium compounds seem to be improbable in non-catalytic, low energetic environments. A high forward energy barrier (EMP2 > 55 kcal mol-1) towards a described transition state restricts the release of CO2. Nevertheless, we propose the release of CO2 on a theoretical level, as been revealed via an intramolecular nucleophilic attack mechanism. Once the challenging transition state for decarboxylation is overcome, a stable Mg-C bond is formed. These mechanistic insights were gained by help of natural bond orbital analysis. The Cα atom (first carbon atom in the ligand chain attached to the carboxyl group) is thought to prefer binding towards the electrophilic magnesium coordination center, rather than towards the electrophilic CO2-carbon atom. Additionally, the putatively formed Grignard-type OH-bearing product molecules possess a more polarized Mg-C bond in comparison to RMgCl species. Therefore, carbanion formation from OH-bearing Grignard-type molecules is made feasible for triggering C-C bond formation reactions. Graphical abstract This study asks whether recently introduced, astrobiologically dihydroxymagnesium carboxylates form Grignard-type reagent molecules via decarboxylative fragmentation.
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6
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Błaziak K, Miller GBS, Ryding MJ, Uggerud E. Reaction Model for the Formation of Benzene from Benzoates and Grignard Reagents. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700816] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Kacper Błaziak
- Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry; Department of Chemistry; University of Oslo; P. O. Box 1033 Blindern 0315 Oslo Norway
| | - Glenn B. S. Miller
- Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry; Department of Chemistry; University of Oslo; P. O. Box 1033 Blindern 0315 Oslo Norway
| | - Mauritz Johan Ryding
- Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry; Department of Chemistry; University of Oslo; P. O. Box 1033 Blindern 0315 Oslo Norway
| | - Einar Uggerud
- Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry; Department of Chemistry; University of Oslo; P. O. Box 1033 Blindern 0315 Oslo Norway
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Abstract
The rich diversity and complexity of organic matter found in meteorites is rapidly expanding our knowledge and understanding of extreme environments from which the early solar system emerged and evolved. Here, we report the discovery of a hitherto unknown chemical class, dihydroxymagnesium carboxylates [(OH)2MgO2CR]-, in meteoritic soluble organic matter. High collision energies, which are required for fragmentation, suggest substantial thermal stability of these Mg-metalorganics (CHOMg compounds). This was corroborated by their higher abundance in thermally processed meteorites. CHOMg compounds were found to be present in a set of 61 meteorites of diverse petrological classes. The appearance of this CHOMg chemical class extends the previously investigated, diverse set of CHNOS molecules. A connection between the evolution of organic compounds and minerals is made, as Mg released from minerals gets trapped into organic compounds. These CHOMg metalorganic compounds and their relation to thermal processing in meteorites might shed new light on our understanding of carbon speciation at a molecular level in meteorite parent bodies.
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8
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Miller GBS, Uggerud E. Dissociation of Mg(ii) and Zn(ii) complexes of simple 2-oxocarboxylates – relationship to CO2fixation, and the Grignard and Barbier reactions. Org Biomol Chem 2017; 15:6813-6825. [DOI: 10.1039/c7ob01327b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The glyoxylate and pyruvate carboxylates have been complexed to Mg(ii) and Zn(ii) to investigate the intrinsic interactions of these important biochemical species in the gas phase.
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Affiliation(s)
- Glenn B. S. Miller
- Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry
- Department of Chemistry
- University of Oslo
- N-0315 Oslo
- Norway
| | - Einar Uggerud
- Mass Spectrometry Laboratory and Centre of Theoretical and Computational Chemistry
- Department of Chemistry
- University of Oslo
- N-0315 Oslo
- Norway
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9
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Hester TH, Albury RM, Pruitt CJM, Goebbert DJ. Fragmentation of [Ni(NO 3) 3] −: A Study of Nickel–Oxygen Bonding and Oxidation States in Nickel Oxide Fragments. Inorg Chem 2016; 55:6634-42. [DOI: 10.1021/acs.inorgchem.6b00812] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas H. Hester
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Rachael M. Albury
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Carrie Jo M. Pruitt
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Daniel J. Goebbert
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
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10
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Schnegelsberg C, Bachmann S, Kolter M, Auth T, John M, Stalke D, Koszinowski K. Association and Dissociation of Grignard Reagents RMgCl and Their Turbo Variant RMgCl⋅LiCl. Chemistry 2016; 22:7752-62. [DOI: 10.1002/chem.201600699] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Christoph Schnegelsberg
- Institut für Organische und Biomolekulare Chemie; Georg-August-Universität Göttingen; Tammannstraße 2 37077 Göttingen Germany
| | - Sebastian Bachmann
- Institut für Anorganische Chemie; Georg-August-Universität Göttingen; Tammannstraße 4 37077 Göttingen Germany
| | - Marlene Kolter
- Institut für Organische und Biomolekulare Chemie; Georg-August-Universität Göttingen; Tammannstraße 2 37077 Göttingen Germany
| | - Thomas Auth
- Institut für Organische und Biomolekulare Chemie; Georg-August-Universität Göttingen; Tammannstraße 2 37077 Göttingen Germany
| | - Michael John
- Institut für Organische und Biomolekulare Chemie; Georg-August-Universität Göttingen; Tammannstraße 2 37077 Göttingen Germany
| | - Dietmar Stalke
- Institut für Anorganische Chemie; Georg-August-Universität Göttingen; Tammannstraße 4 37077 Göttingen Germany
| | - Konrad Koszinowski
- Institut für Organische und Biomolekulare Chemie; Georg-August-Universität Göttingen; Tammannstraße 2 37077 Göttingen Germany
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11
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Dau PD, Rios D, Gong Y, Michelini MC, Marçalo J, Shuh DK, Mogannam M, Van Stipdonk MJ, Corcovilos TA, Martens JK, Berden G, Oomens J, Redlich B, Gibson JK. Synthesis and Hydrolysis of Uranyl, Neptunyl, and Plutonyl Gas-Phase Complexes Exhibiting Discrete Actinide–Carbon Bonds. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00079] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Phuong D. Dau
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Daniel Rios
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Yu Gong
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Maria C. Michelini
- Dipartimento
di Chimica, Università della Calabria, 87030 Arcavacata
di Rende, Italy
| | - Joaquim Marçalo
- Centro
de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, 2695-066 Bobadela LRS, Portugal
| | - David K. Shuh
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Mejdi Mogannam
- Skyline College, San Bruno, California 94066, United States
| | - Michael J. Van Stipdonk
- Department
of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282, United States
| | - Theodore A. Corcovilos
- Department
of Physics, Duquesne University, Pittsburgh, Pennsylvania 15282, United States
| | - Jonathan K. Martens
- Radboud University, Institute for Molecules and
Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - Giel Berden
- Radboud University, Institute for Molecules and
Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - Jos Oomens
- Radboud University, Institute for Molecules and
Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
- van
‘t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
| | - Britta Redlich
- Radboud University, Institute for Molecules and
Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - John K. Gibson
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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Hitzenberger JF, Dammann C, Lang N, Lungerich D, García-Iglesias M, Bottari G, Torres T, Jux N, Drewello T. Making the invisible visible: improved electrospray ion formation of metalloporphyrins/-phthalocyanines by attachment of the formate anion (HCOO(-)). Analyst 2016; 141:1347-55. [PMID: 26753183 DOI: 10.1039/c5an02148k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A protocol is developed for the coordination of the formate anion (HCOO(-)) to neutral metalloporphyrins (Pors) and -phthalocyanines (Pcs) containing divalent metals as a means to improve their ion formation in electrospray ionization (ESI). This method is particularly useful when the oxidation of the neutral metallomacrocycle fails. While focusing on Zn(II)Pors and Zn(II)Pcs, we show that formate is also readily attached to Mn(II), Mg(II) and Co(II)Pcs. However, for the Co(II)Pc secondary reactions can be observed. Upon collision-induced dissociation (CID), Zn(II)Por/Pc·formate supramolecular complexes can undergo the loss of CO2 in combination with transfer of a hydride anion (H(-)) to the zinc metal center. Further dissociation leads to electron transfer and hydrogen atom loss, generating a route to the radical anion of the Zn(II)Por/Pc without the need for electrochemical reduction, although the Zn(II)Por/Pc may have a too low electron affinity to allow electron transfer directly from the formate anion. In addition to single Por molecules, multi Por arrays were successfully analyzed by this method. In this case, multiple addition of formate occurs, giving rise to multiply charged species. In these multi Por arrays, complexation of the formate anion occurs by two surrounding Por units (sandwich). Therefore, the maximum attainment of formate anions in these arrays corresponds to the number of such sandwich complexes rather than the number of porphyrin moieties. The same bonding motif leads to dimers of the composition [(Zn(II)Por/Pc)2·HCOO](-). In these, the formate anion can act as a structural probe, allowing the distinction of isomeric ions with the formate bridging two macrocycles or being attached to a dimer of directly connected macrocycles.
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Affiliation(s)
- Jakob Felix Hitzenberger
- Physical Chemistry I, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 3, 91058 Erlangen, Germany.
| | - Claudia Dammann
- Physical Chemistry I, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 3, 91058 Erlangen, Germany.
| | - Nina Lang
- Organic Chemistry II, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Henkestraße 42, 91054 Erlangen, Germany.
| | - Dominik Lungerich
- Organic Chemistry II, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Henkestraße 42, 91054 Erlangen, Germany.
| | - Miguel García-Iglesias
- Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
| | - Giovanni Bottari
- Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain. and IMDEA-Nanociencia, c/Faraday 9, Campus de Cantoblanco, 28049 Madrid, Spain
| | - Tomás Torres
- Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain. and IMDEA-Nanociencia, c/Faraday 9, Campus de Cantoblanco, 28049 Madrid, Spain
| | - Norbert Jux
- Organic Chemistry II, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Henkestraße 42, 91054 Erlangen, Germany.
| | - Thomas Drewello
- Physical Chemistry I, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 3, 91058 Erlangen, Germany.
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13
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van Huizen NA, Luider TM, Jobst KJ, Terlouw JK, Holmes JL, Burgers PC. Interaction of metal cations with functionalised hydrocarbons in the gas phase: further experimental evidence for solvation of metal ions by the hydrocarbon chain. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2016; 22:61-70. [PMID: 27419899 DOI: 10.1255/ejms.1410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Relative affinity measurements of monovalent metal ions (= Li(+), Cu(+) and Ag(+)) towards aliphatic amines, alcohols and methyl alkanoates (P) have been performed using the kinetic method on the dissociation of metal bound dimer ions of the type P(1)-M(+)-P(2). It was found that the cations' affinity towards long chain (≥C(4) chain length) n- and s-alkylamines, n-alkanols and methyl n- alkanoates was unexpectedly enhanced. This is attributed to a bidentate interaction of the metal ion with the amine, alcohol or ester functional group and the aliphatic chain, paralleling earlier observations on metal bound nitriles. Methyl substitution at the functional group (s-alkylamines compared with n-alkylamines) serves to strengthen only the N•••M(+) bond, and this can be rationalized by the larger proton affinities of s-alkylamines compared to n-alkylamines. This substitution, however, has no effect on the metal ion-hydrocarbon bond. In contrast, methyl substitution remote from the functional group, as in iso-pentylamine, does lead to strengthening of the metal ion-hydrocarbon bond. The cuprous ion affinity of hexadecylamine, C(16)H(33)NH(2) was found to be as large as that for ethylenediamine (352 kJ mol(-1)), known to be a strong copper binding agent. It is argued that such a metal ion-hydrocarbon interaction does not occur in the metal bound dimers.
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Affiliation(s)
- Nick A van Huizen
- Department of Neurology, Laboratory of Neuro-Oncology, Erasmus Medical Center, The Netherlands. Department of Surgery, Erasmus Medical Center, The Netherlands.
| | - Theo M Luider
- D epartment of Neurology, Laboratory of Neuro-Oncology, Erasmus Medical Center, The Netherlands.
| | - Karl J Jobst
- Ontar io Ministry of the Environment and Climate Change, 125 Resources Road, Toronto, Ontario M9P 3V6, Canada. Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada.
| | - Johan K Terlouw
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada.
| | - John L Holmes
- C hemistry Department, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N6N5, Canada.
| | - Peter C Burgers
- D epartment of Neurology, Laboratory of Neuro-Oncology, Erasmus Medical Center, The Netherlands.
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Albury RM, Pruitt CJM, Hester TH, Goebbert DJ. Fragmentation of Cr(NO3)4–: Metal Oxidation upon O•– Abstraction. J Phys Chem A 2015; 119:11471-8. [DOI: 10.1021/acs.jpca.5b08841] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rachael M. Albury
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Carrie Jo M. Pruitt
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Thomas H. Hester
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Daniel J. Goebbert
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
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15
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Lam TW, Zhang H, Siu CK. Reductions of oxygen, carbon dioxide, and acetonitrile by the magnesium(II)/magnesium(I) couple in aqueous media: theoretical insights from a nano-sized water droplet. J Phys Chem A 2015; 119:2780-92. [PMID: 25738586 DOI: 10.1021/jp511490n] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Reductions of O2, CO2, and CH3CN by the half-reaction of the Mg(II)/Mg(I) couple (Mg(2+) + e(-) → Mg(+•)) confined in a nanosized water droplet ([Mg(H2O)16](•+)) have been examined theoretically by means of density functional theory based molecular dynamics methods. The present works have revealed many intriguing aspects of the reaction dynamics of the water clusters within several picoseconds or even in subpicoseconds. The reduction of O2 requires an overall doublet spin state of the system. The reductions of CO2 and CH3CN are facilitated by their bending vibrations and the electron-transfer processes complete within 0.5 ps. For all reactions studied, the radical anions, i.e., O2(•-), CO2(•-), and CH3CN(•-), are initially formed on the cluster surface. O2(•-) and CO2(•-) can integrate into the clusters due to their high hydrophilicity. They are either solvated in the second solvation shell of Mg(2+) as a solvent-separated ion pair (ssip) or directly coordinated to Mg(2+) as a contact-ion pair (cip) having the (1)η-[MgO2](•+) and (1)η-[MgOCO](•+) coordination modes. The (1)η-[MgO2](•+) core is more crowded than the (1)η-[MgOCO](•+) core. The reaction enthalpies of the formation of ssip and cip of [Mg(CO2)(H2O)16](•+) are -36 ± 4 kJ mol(-1) and -30 ± 9 kJ mol(-1), respectively, which were estimated based on the average temperature changes during the ion-molecule reaction between CO2 and [Mg(H2O)16](•+). The values for the formation of ssip and cip of [Mg(O2)(H2O)16](•+) are estimated to be -112 ± 18 kJ mol(-1) and -128 ± 28 kJ mol(-1), respectively. CH3CN(•-) undergoes protonation spontaneously to form the hydrophobic [CH3CN, H](•). Both CH3CN and [CH3CN, H](•) cannot efficiently penetrate into the clusters with activation barriers of 22 kJ mol(-1) and ∼40 kJ mol(-1), respectively. These results provide fundamental insights into the solvation dynamics of the Mg(2+)/Mg(•+) couple on the molecular level.
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Affiliation(s)
- Tim-Wai Lam
- Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, P. R. China
| | - Han Zhang
- Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, P. R. China
| | - Chi-Kit Siu
- Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, P. R. China
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16
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O’Hair RAJ, Rijs NJ. Gas phase studies of the Pesci decarboxylation reaction: synthesis, structure, and unimolecular and bimolecular reactivity of organometallic ions. Acc Chem Res 2015; 48:329-40. [PMID: 25594228 DOI: 10.1021/ar500377u] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
CONSPECTUS: Decarboxylation chemistry has a rich history, and in more recent times, it has been recruited in the quest to develop cheaper, cleaner, and more efficient bond-coupling reactions. Thus, over the past two decades, there has been intense investigation into new metal-catalyzed reactions of carboxylic substrates. Understanding the elementary steps of metal-mediated transformations is at the heart of inventing new reactions and improving the performance of existing ones. Fortunately, during the same time period, there has been a convergence in mass spectrometry (MS) techniques, which allows these catalytic processes to be examined efficiently in the gas phase. Thus, electrospray ionization (ESI) sources have been combined with ion-trap mass spectrometers, which in turn have been modified to either accept radiation from tunable OPO lasers for spectroscopy based structural assignment of ions or to allow the study of ion-molecule reactions (IMR). The resultant "complete" gas-phase chemical laboratories provide a platform to study the elementary steps of metal-catalyzed decarboxylation reactions in exquisite detail. In this Account, we illustrate how the powerful combination of ion trap mass spectrometry experiments and DFT calculations can be systematically used to examine the formation of organometallic ions and their chemical transformations. Specifically, ESI-MS allows the transfer of inorganic carboxylate complexes, [RCO2M(L)n](x), (x = charge) from the condensed to the gas phase. These mass selected ions serve as precursors to organometallic ions [RM(L)n](x) via neutral extrusion of CO2, accessible by slow heating in the ion trap using collision induced dissociation (CID). This approach provides access to an array of organometallic ions with well-defined stoichiometry. In terms of understanding the decarboxylation process, we highlight the role of the metal center (M), the organic group (R), and the auxiliary ligand (L), along with cluster nuclearity, in promoting the formation of the organometallic ion. Where isomeric organometallic ions are generated and normal MS approaches cannot distinguish them, we describe approaches to elucidate the decarboxylation mechanism via determination of their structure. These "unmasked" organometallic ions, [RM(L)n](x), can also be structurally interrogated spectroscopically or via CID. We have thus compared the gas-phase structures and decomposition of several highly reactive and synthetically important organometallic ions for the first time. Perhaps the most significant aspect of this work is the study of bimolecular reactions, which provides experimental information on mechanistically obscure bond-formation and cross-coupling steps and the intrinsic reactivity of ions. We have sought to understand transformations of substrates including acid-base and hydrolysis reactions, along with reactions resulting in C-C bond formation. Our studies also allow a direct comparison of the performance of different metal catalysts in the individual elementary steps associated with protodecarboxylation and decarboxylative alkylation cycles. Electronic structure (DFT and ab initio) and dynamics (RRKM) calculations provide further mechanistic insights into these reactions. The broad implications of this research are that new reactions can be discovered and that the performance of metal catalysts can be evaluated in terms of each of their elementary steps. This has been particularly useful for the study of metal-mediated decarboxylation reactions.
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Affiliation(s)
- Richard A. J. O’Hair
- School of Chemistry, University of Melbourne, Melbourne, Victoria 3010, Australia
- Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- ARC Centre of Excellence in Free Radical Chemistry and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Nicole J. Rijs
- School of Chemistry, University of Melbourne, Melbourne, Victoria 3010, Australia
- Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- ARC Centre of Excellence in Free Radical Chemistry and Biotechnology, The University of Melbourne, Melbourne, Victoria 3010, Australia
- Institut für Chemie, Technische Universität Berlin, Straße des 17. Juni 115, 10623 Berlin, Germany
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17
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Li J, Khairallah GN, O'Hair RAJ. Decarboxylation versus Acetonitrile Loss in Silver Acetate and Silver Propiolate Complexes, [RCO2Ag2(CH3CN)n]+ (where R = CH3 and CH3C≡C; n = 1 and 2). Aust J Chem 2015. [DOI: 10.1071/ch15210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Gas-phase experiments using collision-induced dissociation in an ion trap mass spectrometer have been used in combination with density functional theory (DFT) calculations (at the B3LYP/SDD6–31+G(d) level of theory) to examine the competition between decarboxylation and loss of a coordinated acetonitrile in the unimolecular fragmentation reactions of the silver acetate and silver propiolate complexes, [RCO2Ag2(CH3CN)n]+ (where R = CH3 and CH3C≡C; n = 1 and 2), introduced into the gas-phase via electrospray ionisation. When R = CH3, loss of acetonitrile is the sole reaction channel observed for both complexes (n = 1 and 2), consistent with DFT calculations, which highlight that the barriers for decarboxylation 2.18 eV (n = 2) and 1.96 eV (n = 1) are greater than the binding energies of the coordinated acetonitriles (1.60 eV for n = 2; 1.64 eV for n = 1). In contrast, when R = CH3C≡C, decarboxylation is the main fragmentation pathway observed for both complexes (n = 1 and 2), with loss of acetonitrile only being a minor product channel. This is consistent with DFT calculations, which reveal that the barriers for decarboxylation are 1.17 eV (n = 2) and 1.16 eV (n = 1), which are both below the binding energies of the coordinated acetonitriles (1.55 eV for n = 2; 1.56 eV for n = 1). The barrier for decarboxylation of [CH3C≡CCO2Ag2]+ is 1.22 eV, which is less than the 2.06 eV reported for decarboxylation of [CH3CO2Ag2]+ (Al Sharif et al. Organometallics, 2013, 32, 5416). The observed ease of decarboxylation of silver propiolate complexes in the gas-phase is consistent with the recently reported use of silver salts in metal catalysed decarboxylative C–C and C–X bond forming reactions of propiolic acids.
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18
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Li J, Khairallah GN, Steinmetz V, Maitre P, O'Hair RAJ. Copper mediated decyano decarboxylative coupling of cyanoacetate ligands: Pesci versus Lewis acid mechanism. Dalton Trans 2015; 44:9230-40. [DOI: 10.1039/c5dt00942a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A combination of gas-phase ion trap multistage mass spectrometry (MSn) experiments and density functional theory (DFT) calculations have been used to examine the mechanisms of the sequential decomposition reactions of copper cyanoacetate anions, [(NCCH2CO2)2Cu]−.
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Affiliation(s)
- Jiawei Li
- School of Chemistry
- University of Melbourne
- Australia
- Bio21 Institute of Molecular Science and Biotechnology
- The University of Melbourne
| | - George N. Khairallah
- School of Chemistry
- University of Melbourne
- Australia
- Bio21 Institute of Molecular Science and Biotechnology
- The University of Melbourne
| | - Vincent Steinmetz
- Laboratoire de Chimie Physique
- UMR8000 CNRS
- Université Paris-Sud
- Orsay
- France
| | - Philippe Maitre
- Laboratoire de Chimie Physique
- UMR8000 CNRS
- Université Paris-Sud
- Orsay
- France
| | - Richard A. J. O'Hair
- School of Chemistry
- University of Melbourne
- Australia
- Bio21 Institute of Molecular Science and Biotechnology
- The University of Melbourne
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19
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Khairallah GN, da Silva G, O'Hair RAJ. Molecular salt effects in the gas phase: tuning the kinetic basicity of [HCCLiCl]⁻ and [HCCMgCl₂]⁻ by LiCl and MgCl₂. Angew Chem Int Ed Engl 2014; 53:10979-83. [PMID: 25079912 DOI: 10.1002/anie.201404362] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 06/11/2014] [Indexed: 11/09/2022]
Abstract
A combination of gas-phase ion-molecule reaction experiments and theoretical kinetic modeling is used to examine how a salt can influence the kinetic basicity of organometallates reacting with water. [HC≡CLiCl](-) reacts with water more rapidly than [HC≡CMgCl2](-), consistent with the higher reactivity of organolithium versus organomagnesium reagents. Addition of LiCl to [HC≡CLiCl](-) or [HC≡CMgCl2](-) enhances their reactivity towards water by a factor of about 2, while addition of MgCl2 to [HC≡CMgCl2](-) enhances its reactivity by a factor of about 4. Ab initio calculations coupled with master equation/RRKM theory kinetic modeling show that these reactions proceed via a mechanism involving formation of a water adduct followed by rearrangement, proton transfer, and acetylene elimination as either discrete or concerted steps. Both the energy and entropy requirements for these elementary steps need to be considered in order to explain the observed kinetics.
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Affiliation(s)
- George N Khairallah
- School of Chemistry and Bio21 Institute, University of Melbourne, Melbourne, Victoria 3010 (Australia); ARC Centre of Excellence for Free-Radical Chemistry and Biotechnology.
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20
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Woolley M, Khairallah GN, da Silva G, Donnelly PS, O’Hair RAJ. Direct versus Water-Mediated Protodecarboxylation of Acetic Acid Catalyzed by Group 10 Carboxylates, [(phen)M(O2CCH3)]+. Organometallics 2014. [DOI: 10.1021/om500493w] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Matthew Woolley
- School of Chemistry, ‡Bio21 Institute of Molecular Science
and Biotechnology, §ARC Centre of Excellence
for Free Radical Chemistry and Biotechnology, and ∥Department of Chemical and Biomolecular
Engineering, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - George N. Khairallah
- School of Chemistry, ‡Bio21 Institute of Molecular Science
and Biotechnology, §ARC Centre of Excellence
for Free Radical Chemistry and Biotechnology, and ∥Department of Chemical and Biomolecular
Engineering, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Gabriel da Silva
- School of Chemistry, ‡Bio21 Institute of Molecular Science
and Biotechnology, §ARC Centre of Excellence
for Free Radical Chemistry and Biotechnology, and ∥Department of Chemical and Biomolecular
Engineering, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Paul S. Donnelly
- School of Chemistry, ‡Bio21 Institute of Molecular Science
and Biotechnology, §ARC Centre of Excellence
for Free Radical Chemistry and Biotechnology, and ∥Department of Chemical and Biomolecular
Engineering, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Richard A. J. O’Hair
- School of Chemistry, ‡Bio21 Institute of Molecular Science
and Biotechnology, §ARC Centre of Excellence
for Free Radical Chemistry and Biotechnology, and ∥Department of Chemical and Biomolecular
Engineering, The University of Melbourne, Melbourne, Victoria 3010, Australia
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21
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Bodo E, Ciavardini A, Dalla Cort A, Giannicchi I, Yafteh Mihan F, Fornarini S, Vasile S, Scuderi D, Piccirillo S. Anion Recognition by Uranyl-Salophen Derivatives as Probed by Infrared Multiple Photon Dissociation Spectroscopy and Ab Initio Modeling. Chemistry 2014; 20:11783-92. [DOI: 10.1002/chem.201402788] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 06/02/2014] [Indexed: 11/11/2022]
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22
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Khairallah GN, da Silva G, O'Hair RAJ. Molecular Salt Effects in the Gas Phase: Tuning the Kinetic Basicity of [HCCLiCl]−and [HCCMgCl2]−by LiCl and MgCl2. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201404362] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Bluemke TD, Clegg W, García-Alvarez P, Kennedy AR, Koszinowski K, McCall MD, Russo L, Hevia E. Structural and reactivity insights in Mg–Zn hybrid chemistry: Zn–I exchange and Pd-catalysed cross-coupling applications of aromatic substrates. Chem Sci 2014. [DOI: 10.1039/c4sc01263a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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24
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Hale RD, Chan CC, Weisbecker CS, Attygalle AB. Gas-phase fragmentation of metal adducts of alkali-metal oxalate salts. JOURNAL OF MASS SPECTROMETRY : JMS 2014; 49:195-200. [PMID: 24619545 DOI: 10.1002/jms.3322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Revised: 11/24/2013] [Accepted: 12/01/2013] [Indexed: 06/03/2023]
Abstract
Upon collisional activation, gaseous metal adducts of lithium, sodium and potassium oxalate salts undergo an expulsion of CO2, followed by an ejection of CO to generate a product ion that retains all three metals atoms of the precursor. Spectra recorded even at very low collision energies (2 eV) showed peaks for a 44-Da neutral fragment loss. Density functional theory calculations predicted that the ejection of CO2 requires less energy than an expulsion of a Na(+) and that the [Na3CO2](+) product ion formed in this way bears a planar geometry. Furthermore, spectra of [Na3C2O4](+) and [(39)K3C2O4](+) recorded at higher collision energies showed additional peaks at m/z 90 and m/z 122 for the radical cations [Na2CO2](+•) and [K2CO2](+•), respectively, which represented a loss of an M(•) from the precursor ions. Moreover, [Na3CO2](+), [(39)K3CO2](+) and [Li3CO2](+) ions also undergo a CO loss to form [M3O](+). Furthermore, product-ion spectra for [Na3C2O4](+) and [(39)K3C2O4](+) recorded at low collision energies showed an unexpected peak at m/z 63 for [Na2OH](+) and m/z 95 for [(39)K2OH](+), respectively. An additional peak observed at m/z 65 for [Na2(18)OH](+) in the spectrum recorded for [Na3C2O4](+), after the addition of some H2(18)O to the collision gas, confirmed that the [Na2OH](+) ion is formed by an ion-molecule reaction with residual water in the collision cell.
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Affiliation(s)
- Robert D Hale
- Stevens Institute of Technology, Chemistry and Chemical Biology, Hoboken, NJ, USA
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25
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Rijs NJ, Yoshikai N, Nakamura E, O’Hair RAJ. Unraveling Organocuprate Complexity: Fundamental Insights into Intrinsic Group Transfer Selectivity in Alkylation Reactions. J Org Chem 2014; 79:1320-34. [DOI: 10.1021/jo4027325] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
| | - Naohiko Yoshikai
- Division
of Chemistry and Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, Singapore 637371
| | - Eiichi Nakamura
- Department
of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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26
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Rodríguez-Blanco G, Jobst KJ, Luider TM, Terlouw JK, Burgers PC. Generation and Dissociation of RCOOCaCl2−and other Carboxylate-Substituted Superhalogens: CO2Capture and Implications for Structure Analysis. Chempluschem 2013; 78:1184-1189. [DOI: 10.1002/cplu.201300161] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 07/16/2013] [Indexed: 11/08/2022]
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