1
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Saju A, Crawley MR, MacMillan SN, Lacy DC. Manganese(III) Nitrate Complexes as Bench-Stable Powerful Oxidants. J Am Chem Soc 2024; 146:11616-11621. [PMID: 38639535 DOI: 10.1021/jacs.4c03411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
We report herein a convenient one-pot synthesis for the shelf-stable molecular complex [Mn(NO3)3(OPPh3)2] (2) and describe the properties that make it a powerful and selective one-electron oxidation (deelectronation) reagent. 2 has a high reduction potential of 1.02 V versus ferrocene (MeCN) (1.65 vs normal hydrogen electrode), which is one the highest known among readily available redox agents used in chemical synthesis. 2 exhibits stability toward air in the solid state, can be handled with relative ease, and is soluble in most common laboratory solvents such as MeCN, dichloromethane, and fluorobenzene. 2 is substitutionally labile with respect to the coordinated (pseudo)halide ions enabling the synthesis of other new Mn(III) nitrato complexes also with high reduction potentials ranging from 0.6 to 1.0 V versus ferrocene.
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Affiliation(s)
- Ananya Saju
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States
| | - Matthew R Crawley
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States
| | - Samantha N MacMillan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - David C Lacy
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States
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2
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Zhang YQ, Zhang Y, Zeng G, Liao RZ, Li M. Mechanism of photocatalytic CO 2 reduction to HCO 2H by a robust multifunctional iridium complex. Dalton Trans 2024; 53:684-698. [PMID: 38078488 DOI: 10.1039/d3dt03329e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
The tetradentate PNNP-type IrIII complex Mes-IrPCY2 ([Cl-IrIII-H]+) is reported to be an efficient catalyst for the reduction of CO2 to formate with excellent selectivity under visible light irradiation. Density functional calculations have been carried out to elucidate the mechanism and the origin of selectivity in the present work. Calculations suggest that the double-reduced complex 1-H (1[IrI-H]0) demonstrates higher activity than the single-reduced complex 2-H (2[IrIII(L˙-)-H]+), possibly owing to the higher hydride donor ability of the former compared to the latter; thus 1-H functions as the active species in the overall CO2 reduction reaction. In the HCOO- formation pathway, the hydride of 1-H performs a nucleophilic attack on CO2via an outer-sphere fashion to generate species 1-OCHO (1[IrI-OCHO]0), which then releases HCOO- to produce an IrI intermediate. A subsequent protonation and chloride coordination of the Ir center leads to the regeneration of catalyst 1[Cl-IrIII-H]+. For the CO production, a nucleophilic attack on CO2 takes place by the Ir atom of 1-Hvia an inner-sphere manner to afford complex O2C-3-H (1[O2C-IrIII-H]0), followed by a two-proton-one-electron reduction to furnish the OC-2-H complex (2[OC-IrIII(L˙-)-H]+) after liberating a H2O. Ultimately, CO is released to form 2-H. The stronger nucleophilicity as well as smaller steric hindrance of the hydride than the Ir atom of the active species 1-H (1[IrI-H]0) is found to account for the favoring of formate formation over CO formation. Meanwhile, the CO2 reduction reaction is calculated to be preferred over the hydrogen evolution reaction, and this is consistent with the experimental product distributions.
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Affiliation(s)
- Ya-Qiong Zhang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
- Hubei Key Laboratory of Purification and Application of Plant Anti-Cancer Active Ingredients, College of Chemistry and Life Science, Hubei University of Education, Wuhan, 430205, China
| | - Yu Zhang
- Hubei Key Laboratory of Purification and Application of Plant Anti-Cancer Active Ingredients, College of Chemistry and Life Science, Hubei University of Education, Wuhan, 430205, China
| | - Guoping Zeng
- Hubei Key Laboratory of Purification and Application of Plant Anti-Cancer Active Ingredients, College of Chemistry and Life Science, Hubei University of Education, Wuhan, 430205, China
| | - Rong-Zhen Liao
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
| | - Man Li
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
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3
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Alcázar JJ, Misad Saide AC, Campodónico PR. Reliable and accurate prediction of basic pK[Formula: see text] values in nitrogen compounds: the pK[Formula: see text] shift in supramolecular systems as a case study. J Cheminform 2023; 15:90. [PMID: 37770903 PMCID: PMC10540475 DOI: 10.1186/s13321-023-00763-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 09/20/2023] [Indexed: 09/30/2023] Open
Abstract
This article presents a quantitative structure-activity relationship (QSAR) approach for predicting the acid dissociation constant (pK[Formula: see text]) of nitrogenous compounds, including those within supramolecular complexes based on cucurbiturils. The model combines low-cost quantum mechanical calculations with QSAR methodology and linear regressions to achieve accurate predictions for a broad range of nitrogen-containing compounds. The model was developed using a diverse dataset of 130 nitrogenous compounds and exhibits excellent predictive performance, with a high coefficient of determination (R[Formula: see text]) of 0.9905, low standard error (s) of 0.3066, and high Fisher statistic (F) of 2142. The model outperforms existing methods, such as Chemaxon software and previous studies, in terms of accuracy and its ability to handle heterogeneous datasets. External validation on pharmaceutical ingredients, dyes, and supramolecular complexes based on cucurbiturils confirms the reliability of the model. To enhance usability, a script-like tool has been developed, providing a streamlined process for users to access the model. This study represents a significant advancement in pK[Formula: see text] prediction, offering valuable insights for drug design and supramolecular system optimization.
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Affiliation(s)
- Jackson J. Alcázar
- Centro de Química Médica, Universidad del Desarrollo, Av.Plaza 680, 7780272 Santiago, RM Chile
| | | | - Paola R. Campodónico
- Centro de Química Médica, Universidad del Desarrollo, Av.Plaza 680, 7780272 Santiago, RM Chile
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4
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Radtke V, Priester D, Heering A, Müller C, Koslowski T, Leito I, Krossing I. The Unified Redox Scale for All Solvents: Consistency and Gibbs Transfer Energies of Electrolytes from their Constituent Single Ions. Chemistry 2023; 29:e202300609. [PMID: 37191477 DOI: 10.1002/chem.202300609] [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: 02/23/2023] [Revised: 04/28/2023] [Accepted: 05/11/2023] [Indexed: 05/17/2023]
Abstract
We have devised the unified redox scale Eabs H2O , which is valid for all solvents. The necessary single ion Gibbs transfer energy between two different solvents, which only can be determined with extra-thermodynamic assumptions so far, must clearly satisfy two essential conditions: First, the sum of the independent cation and anion values must give the Gibbs transfer energy of the salt they form. The latter is an observable and measurable without extra-thermodynamic assumptions. Second, the values must be consistent for different solvent combinations. With this work, potentiometric measurements on silver ions and on chloride ions show that both conditions are fulfilled using a salt bridge filled with the ionic liquid [N2225 ][NTf2 ]: if compared to the values resulting from known pKL values, the silver and chloride single ion magnitudes combine within a uncertainty of 1.5 kJ mol-1 to the directly measurable transfer magnitudes of the salt AgCl from water to the solvents acetonitrile, propylene carbonate, dimethylformamide, ethanol, and methanol. The resulting values are used to further develop the consistent unified redox potential scale Eabs H2O that now allows to assess and compare redox potentials in and over six different solvents. We elaborate on its implications.
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Affiliation(s)
- Valentin Radtke
- Institut für Anorganische und, Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Denis Priester
- Institut für Anorganische und, Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Agnes Heering
- Institute of Chemistry, University of Tartu, Ravila 14a Str, 50411, Tartu, Estonia
| | - Carina Müller
- Institut für Anorganische und, Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Thorsten Koslowski
- Institut für Physikalische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Ivo Leito
- Institute of Chemistry, University of Tartu, Ravila 14a Str, 50411, Tartu, Estonia
| | - Ingo Krossing
- Institut für Anorganische und, Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstr. 21, 79104, Freiburg, Germany
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5
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Chong SL, Tan IS, Foo HCY, Chan YS, Lam MK, Lee KT. Ultrasonic‑assisted molten salt hydrates pretreated Eucheuma cottonii residues as a greener precursor for third-generation l-lactic acid production. BIORESOURCE TECHNOLOGY 2022; 364:128136. [PMID: 36257523 DOI: 10.1016/j.biortech.2022.128136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
This study aims to establish an efficient pretreatment method that facilitates the conversion of sugars from macroalgae wastes, Eucheuma cottonii residues (ECRs) during hydrolysis and subsequently enhances l-lactic acid (L-LA) production. Hence, ultrasonic-assisted molten salt hydrates (UMSHs) pretreatment was proposed to enhance the accessibility of ECRs to hydrolyze into glucose through dilute acid hydrolysis (DAH). The obtained hydrolysates were employed as the substrate in producing L-LA by separate hydrolysis and fermentation (SHF). The maximum glucose yield (97.75 %) was achieved using UMSHs pretreated ECRs with 40 wt% ZnCl2 at 80 °C for 2 h and followed with DAH. The optimum glucose to L-LA yield obtained for SHF was 90.08 % using 5 % (w/w) inoculum cell densities of B. coagulans ATCC 7050 with yeast extract (YE). A comparable performance (89.65 %) was obtained using a nutrient combination (lipid-extracted Chlorella vulgaris residues (CVRs), vitamin B3, and vitamin B5) as a partial alternative for YE.
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Affiliation(s)
- Soo Ling Chong
- Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University Malaysia, CDT 250, 98009 Miri, Sarawak, Malaysia
| | - Inn Shi Tan
- Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University Malaysia, CDT 250, 98009 Miri, Sarawak, Malaysia.
| | - Henry Chee Yew Foo
- Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University Malaysia, CDT 250, 98009 Miri, Sarawak, Malaysia
| | - Yen San Chan
- Department of Chemical and Energy Engineering, Faculty of Engineering and Science, Curtin University Malaysia, CDT 250, 98009 Miri, Sarawak, Malaysia
| | - Man Kee Lam
- Chemical Engineering Department, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia; HICoE-Centre for Biofuel and Biochemical Research, Institute of Self-Sustainable Building, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia
| | - Keat Teong Lee
- School of Chemical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Penang, Malaysia
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6
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Zhang YQ, Wang ZH, Li M, Liao RZ. Understanding the chemoselectivity switch in CO2 reduction catalyzed by Co and Fe complexes bearing a pentadentate N5 ligand. J Catal 2022. [DOI: 10.1016/j.jcat.2022.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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7
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Rall JM, Schorpp M, Keilwerth M, Mayländer M, Friedmann C, Daub M, Richert S, Meyer K, Krossing I. Synthesis and Characterization of Stable Iron Pentacarbonyl Radical Cation Salts. Angew Chem Int Ed Engl 2022; 61:e202204080. [PMID: 35543697 PMCID: PMC9401057 DOI: 10.1002/anie.202204080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Indexed: 11/09/2022]
Abstract
The open‐shell iron pentacarbonyl cation [Fe(CO)5].+ was isolated by deelectronation, i.e., the single‐electron oxidation of the parent neutral Fe(CO)5 using [phenazineF].+ as the [Al(ORF)4]− and [F‐{Al(ORF)3}2]− salt (RF=C(CF3)3; phenazineF=perfluoro‐5,10‐bis(perfluorophenyl)‐5,10‐dihydrophenazine). [Fe(CO)5].+[Al(ORF)4]− was fully characterized (scXRD analysis, IR, NMR, EPR, 57Fe spectroscopy, CV and SQUID magnetization study) and, apart from being a compound of fundamental interest, may serve as a precursor for low‐valent iron coordination chemistry.
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Affiliation(s)
- Jan M. Rall
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Marcel Schorpp
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Martin Keilwerth
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Department für Chemie und Pharmazie Anorganische Chemie Egerlandstrasse 1 91059 Erlangen Germany
| | - Maximilian Mayländer
- Institut für Physikalische Chemie Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Christian Friedmann
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Michael Daub
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Sabine Richert
- Institut für Physikalische Chemie Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Department für Chemie und Pharmazie Anorganische Chemie Egerlandstrasse 1 91059 Erlangen Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
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8
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Radtke V, Gebel N, Priester D, Ermantraut A, Bäuerle M, Himmel D, Stroh R, Koslowski T, Leito I, Krossing I. Measurements and Utilization of Consistent Gibbs Energies of Transfer of Single Ions: Towards a Unified Redox Potential Scale for All Solvents. Chemistry 2022; 28:e202200509. [PMID: 35446995 PMCID: PMC9401597 DOI: 10.1002/chem.202200509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Indexed: 11/08/2022]
Abstract
Utilizing the “ideal” ionic liquid salt bridge to measure Gibbs energies of transfer of silver ions between the solvents water, acetonitrile, propylene carbonate and dimethylformamide results in a consistent data set with a precision of 0.6 kJ mol−1 over 87 measurements in 10 half‐cells. This forms the basis for a coherent experimental thermodynamic framework of ion solvation chemistry. In addition, we define the solvent independent peabsH2O
‐ and the EabsH2O
values that account for the electronating potential of any redox system similar to the pHabsH2O
value of a medium that accounts for its protonating potential. This EabsH2O
scale is thermodynamically well‐defined enabling a straightforward comparison of the redox potentials (reducities) of all media with respect to the aqueous redox potential scale, hence unifying all conventional solvents′ redox potential scales. Thus, using the Gibbs energy of transfer of the silver ion published herein, one can convert and unify all hitherto published redox potentials measured, for example, against ferrocene, to the EabsH2O
scale.
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Affiliation(s)
- Valentin Radtke
- Institut für Anorganische und Analytische Chemie Freiburger Materialforschungszentrum (FMF) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Niklas Gebel
- Institut für Anorganische und Analytische Chemie Freiburger Materialforschungszentrum (FMF) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Denis Priester
- Institut für Anorganische und Analytische Chemie Freiburger Materialforschungszentrum (FMF) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Andreas Ermantraut
- Institut für Anorganische und Analytische Chemie Freiburger Materialforschungszentrum (FMF) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Monika Bäuerle
- Institut für Anorganische und Analytische Chemie Freiburger Materialforschungszentrum (FMF) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Daniel Himmel
- Institut für Anorganische und Analytische Chemie Freiburger Materialforschungszentrum (FMF) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Regina Stroh
- Institut für Anorganische und Analytische Chemie Freiburger Materialforschungszentrum (FMF) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Thorsten Koslowski
- Institut für Physikalische Chemie Albert-Ludwigs-Universität Freiburg Albertstr. 23a 79104 Freiburg Germany
| | - Ivo Leito
- Institute of Chemistry University of Tartu Ravila 14a Str 50411 Tartu Estonia
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie Freiburger Materialforschungszentrum (FMF) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
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9
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Rall JM, Schorpp M, Keilwerth M, Mayländer M, Friedmann C, Daub M, Richert S, Meyer K, Krossing I. Synthesis and Characterization of Stable Iron Pentacarbonyl Radical Cation Salts. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jan M. Rall
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Marcel Schorpp
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Martin Keilwerth
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Department für Chemie und Pharmazie Anorganische Chemie Egerlandstrasse 1 91059 Erlangen Germany
| | - Maximilian Mayländer
- Institut für Physikalische Chemie Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Christian Friedmann
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Michael Daub
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Sabine Richert
- Institut für Physikalische Chemie Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Department für Chemie und Pharmazie Anorganische Chemie Egerlandstrasse 1 91059 Erlangen Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie und Freiburger Materialforschungszentrum (FMF) Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
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10
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He T, Klare HFT, Oestreich M. Perdeuteration of Deactivated Aryl Halides by H/D Exchange under Superelectrophile Catalysis. J Am Chem Soc 2022; 144:4734-4738. [PMID: 35258291 DOI: 10.1021/jacs.2c00080] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Superelectrophilic silylium/arenium ions are shown to be highly effective H/D exchange promoters for the exhaustive deuteration of electron-deficient aryl halides. Several of the resulting perdeuterated aryl halides have been previously inaccessible with existing deuterium-labeling procedures. Using inexpensive C6D6 as the deuterium source, excellent degrees of deuterium incorporation were achieved under ambient reaction conditions. Importantly, the perdeuteration remains unaffected on multigram scale, even at a reduced catalyst loading of 0.1 mol %. By this method, otherwise expensive or noncommercially available NMR solvents such as 1,2-dichloro- and 1,2-difluorobenzene can be prepared.
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Affiliation(s)
- Tao He
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Hendrik F T Klare
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Martin Oestreich
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
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11
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Zhang YQ, Li YY, Maseras F, Liao RZ. Mechanism and selectivity of photocatalyzed CO 2 reduction by a function-integrated Ru catalyst. Dalton Trans 2022; 51:3747-3759. [PMID: 35168249 DOI: 10.1039/d1dt03825g] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The phosphine-substituted Ru(II) polypyridyl complex, [RuII-(tpy)(pqn)(MeCN)]2+ (RuP), was disclosed to be an efficient photocatalyst for the reduction of CO2 to CO with excellent selectivity. In this work, density functional calculations were performed to elucidate the reaction mechanism and understand the origin of selectivity. The calculations showed that RuP was first excited to the singlet excited state, followed by intersystem crossing to produce a triplet species (3RuIII(L˙-)-S), which was then reduced by the sacrificial electron donor BIH to generate a RuII(L˙-) intermediate. The ligand of RuII(L˙-) was further reduced to produce a RuII(L2-) intermediate. The redox non-innocent nature of the tpy and pqn ligands endows the Ru center with an oxidation state of +2 after two one-electron reductions. RuII(L2-) nucleophilically attacks CO2, in which two electrons are delivered from the ligands to CO2, affording a RuII-COOH species after protonation. This is followed by the protonation of the hydroxyl moiety of RuII-COOH, coupled with the C-O bond cleavage, resulting in the formation of RuII-CO. Ultimately, CO is dissociated after two one-electron reductions. Protonation of RuII(L2-) to generate a RuII-hydride, a critical intermediate for the production of formate and H2, turns out to be kinetically less favorable, even though it is thermodynamically more favorable. This fact is due to the presence of a Ru2+ ion in the reduced catalyst, which disfavors its protonation.
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Affiliation(s)
- Ya-Qiong Zhang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Ying-Ying Li
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Feliu Maseras
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avgda. Països Catalans, 16, 43007 Tarragona, Catalonia, Spain
| | - Rong-Zhen Liao
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
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12
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Deleebeeck L, Snedden A, Stoica D. Reconciling the pHe measurements of bioethanol: pHabs measurements of buffered 50-50 wt% water-ethanol mixtures. Anal Chim Acta X 2022; 10:100085. [PMID: 35923414 PMCID: PMC9240372 DOI: 10.1016/j.acax.2022.100085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 10/29/2021] [Accepted: 06/19/2022] [Indexed: 11/25/2022] Open
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13
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Electrolyte acidification from anode reactions during lithium mediated ammonia synthesis. Electrochem commun 2022. [DOI: 10.1016/j.elecom.2021.107186] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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14
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Sellin M, Friedmann C, Mayländer M, Richert S, Krossing I. Towards Clustered Carbonyl Cations [M
3
(CO)
14
]
2+
(M = Ru, Os): The Need for Innocent Deelectronation . Chem Sci 2022; 13:9147-9158. [PMID: 36093020 PMCID: PMC9384829 DOI: 10.1039/d2sc02358j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 07/07/2022] [Indexed: 11/21/2022] Open
Abstract
To access the hitherto almost unknown class of clustered transition metal carbonyl cations, the trimetal dodecacarbonyls M3(CO)12 (M = Ru, Os) were reacted with the oxidant Ag+[WCA]−, but yielded the silver complexes [Ag{M3(CO)12}2]+[WCA]−...
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Affiliation(s)
- Malte Sellin
- Institut für Anorganische und Analytische Chemie, Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Christian Friedmann
- Institut für Anorganische und Analytische Chemie, Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Maximilian Mayländer
- Institut für Physikalische Chemie, Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Sabine Richert
- Institut für Physikalische Chemie, Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie, Albert-Ludwigs-Universität Freiburg Albertstr. 21 79104 Freiburg Germany
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15
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Bhattacharjee A, Brown DSV, Virca CN, Ethridge TE, Mendez Galue O, Pham UT, McCormick TM. Computational investigation into intramolecular hydrogen bonding controlling the isomer formation and pKa of octahedral nickel (II) proton reduction catalysts. Dalton Trans 2022; 51:3676-3685. [DOI: 10.1039/d2dt00043a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work demonstrates the impact of intramolecular hydrogen bonding (H-bonding) on the calculated pKa of octahedral tris-(pyridinethiolato)nickel (II), [Ni(PyS)3]-, proton reduction catalysts. Density Functional Theory (DFT) calculations on a [Ni(PyS)3]-...
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16
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Raubenheimer HG, Mapolie SF. Acid and base strength variations: rationalization for cyclic amine bases and acidic aqua cations. Dalton Trans 2021; 50:17864-17878. [PMID: 34792051 DOI: 10.1039/d1dt02940a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This perspective highlights and evaluates recent key developments in the thermodynamic approach used to analyze trends in acid and base strength variation. According to this approach, acid and base strength ranking can be interpreted by using thermodynamic or thermochemical cycles. Each cycle generally consists of three independent but well-defined steps. The modus operandi described here entails the identification of the dominant step and the rationalization of its free energy/enthalpy/energy change along a selected series in terms of known structural chemical concepts. Developments in this approach are described by focusing on two related series of bases and two series of acids. In the case of the former the protonation of a series of N-heterocyclic amine bases together with their methyl-substituted analogs receives particular attention while in the case of acids, the acidic properties of aqua dications of elements in period 4 and group 2 are probed. It is illustrated how significant progress in computational chemistry and mass spectrometric techniques can be employed to compare 'inherent' basicity or acidity in the selected families of compounds by using simple gas-phase energy cycles. Unique, dual functions for both electronegativity (element and orbital) and charge density (for aqua cations) indicators are identified and used to evaluate these cycles. Solvent effects (in aqueous solution) are accommodated by including dehydration and hydration changes in appropriately-extended, three-step free energy cycles. It is further suggested that the dominant step in the extended thermodynamic cycle for monomeric aqua cations is the transfer of M(H2O)n2+ complex hydrates from the gas-phase to bulk water. Charge density of the aqua cations again features prominently in proposed rationalizations. Finally, this article also sheds light on salient relationships that exist between empirically and quantum-chemically estimated enthalpy and entropy changes for the aforementioned transfer process.
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Affiliation(s)
- Helgard G Raubenheimer
- Department of Chemistry and Polymer Science, University of Stellenbosch, 7602, Matieland, South Africa.
| | - Selwyn F Mapolie
- Department of Chemistry and Polymer Science, University of Stellenbosch, 7602, Matieland, South Africa.
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17
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da Silva RJNB, Saame J, Anes B, Heering A, Leito I, Näykki T, Stoica D, Deleebeeck L, Bastkowski F, Snedden A, Camões MF. Evaluation and validation of detailed and simplified models of the uncertainty of unified [Formula: see text] measurements in aqueous solutions. Anal Chim Acta 2021; 1182:338923. [PMID: 34602195 DOI: 10.1016/j.aca.2021.338923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 11/24/2022]
Abstract
The use of the unified pH concept, [Formula: see text] , applicable to aqueous and non-aqueous solutions, which allows interpreting and comparison of the acidity of different types of solutions, requires reliable and objective determination. The [Formula: see text] can be determined by a single differential potentiometry measurement referenced to an aqueous reference buffer or by a ladder of differential potentiometric measurements that allows minimisation of inconsistencies of various determinations. This work describes and assesses bottom-up evaluations of the uncertainty of these measurements, where uncertainty components are combined by the Monte Carlo Method (MCM) or Taylor Series Approximation (TSM). The MCM allows a detailed simulation of the measurements, including an iterative process involving in minimising ladder deviations. On the other hand, the TSM requires the approximate determination of minimisation uncertainty. The uncertainty evaluation was successfully applied to measuring aqueous buffers with pH of 2.00, 4.00, 7.00, and 10.00, with a standard uncertainty of 0.01. The reference and estimated values from both approaches are metrologically compatible for a 95% confidence level even when a negligible contribution of liquid junction potential uncertainty is assumed. The MCM estimated pH values with an expanded uncertainty, for the 95% confidence level, between 0.26 and 0.51, depending on the pH value and ladder inconsistencies. The minimisation uncertainty is negligible or responsible for up to 87% of the measurement uncertainty. The TSM quantified measurement uncertainties on average only 0.05 units larger than the MCM estimated ones. Additional experimental tests should be performed to test these uncertainty models for analysis performed in other laboratories and on non-aqueous solutions.
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Affiliation(s)
| | - Jaan Saame
- University of Tartu, Institute of Chemistry, Ravila 14a, 50411, Tartu, Estonia
| | - Bárbara Anes
- Centro de Química Estutural, Faculdade de Ciências da Universidade de Lisboa, Ed. C8, Campo Grande, 1649-016, Lisboa, Portugal
| | - Agnes Heering
- University of Tartu, Institute of Chemistry, Ravila 14a, 50411, Tartu, Estonia
| | - Ivo Leito
- University of Tartu, Institute of Chemistry, Ravila 14a, 50411, Tartu, Estonia
| | - Teemu Näykki
- Finnish Environment Institute SYKE, Laboratory Centre, Mustialankatu 3, 00790, Helsinki, Finland
| | - Daniela Stoica
- Laboratoire National de Metrologie et D'Essais, 1 Rue Gaston Boissier, 75015, Paris, France
| | | | - Frank Bastkowski
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116, Braunschweig, Germany
| | | | - M Filomena Camões
- Centro de Química Estutural, Faculdade de Ciências da Universidade de Lisboa, Ed. C8, Campo Grande, 1649-016, Lisboa, Portugal
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18
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Klare HFT, Oestreich M. The Power of the Proton: From Superacidic Media to Superelectrophile Catalysis. J Am Chem Soc 2021; 143:15490-15507. [PMID: 34520196 DOI: 10.1021/jacs.1c07614] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Superacidic media became famous in connection with carbocations. Yet not all reactive intermediates can be generated, characterized, and eventually isolated from these Brønsted acid/Lewis acid cocktails. The counteranion, that is the conjugate base, in these systems is often too nucleophilic and/or engages in redox chemistry with the newly formed cation. The Brønsted acidity, especially superacidity, is in fact often not even crucial unless protonation of extremely weak bases needs to be achieved. Instead, it is the chemical robustness of the aforementioned counteranion that determines the success of the protolysis. The advent of molecular Brønsted superacids derived from weakly coordinating, redox-inactive counteranions that do withstand the enormous reactivity of superelectrophiles such as silicon cations completely changed the whole field. This Perspective summarizes general aspects of medium and molecular Brønsted acidity and shows how applications of molecular Brønsted superacids have advanced from stoichiometric reactions to catalytic processes involving protons and in situ generated superelectrophiles.
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Affiliation(s)
- Hendrik F T Klare
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
| | - Martin Oestreich
- Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany
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19
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Radtke V, Stoica D, Leito I, Camões F, Krossing I, Anes B, Roziková M, Deleebeeck L, Veltzé S, Näykki T, Bastkowski F, Heering A, Dániel N, Quendera R, Liv L, Uysal E, Lawrence N. A unified pH scale for all solvents: part I – intention and reasoning (IUPAC Technical Report). PURE APPL CHEM 2021. [DOI: 10.1515/pac-2019-0504] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The definition of pH, its measurement and standard buffers, is well developed in aqueous solutions. Its definition in solvents other than water has been elaborated for a couple of solvents and their mixtures with water. However, the definition of a universal pH scale spanning all solvents and phases, not to mention standard procedures of measurement, is still a largely uncharted territory. UnipHied is a European collaboration and has the goal of putting the theoretical concept of an earlier introduced (2010) unified pHabs scale on a metrologically well-founded basis into practice. The pHabs scale enables the comparability of acidity between different phases. This article draws the connection of the concepts of unified acidity and secondary pH measurement.
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Affiliation(s)
- Valentin Radtke
- Universität Freiburg, IAAC , Albertstr. 21, 79104 Freiburg , Germany
| | - Daniela Stoica
- Laboratoire de Métrologie et d’Essais , 1 Rue Gaston Boissier, 75015 , Paris , France
| | - Ivo Leito
- University of Tartu , 14a Ravila Street, 50411 Tartu , Estonia
| | - Filomena Camões
- FCiências.ID, Centro de Química Estrutural, Faculdade de Ciências da Universidade de Lisboa , Campo Grande, 1749-016 Lisboa , Portugal
| | - Ingo Krossing
- Universität Freiburg, IAAC , Albertstr. 21, 79104 Freiburg , Germany
| | - Bárbara Anes
- FCiências.ID , Centro de Química Estrutural , Faculdade de Ciências da Universidadede Lisboa, Campo Grande , 1749-016 Lisboa , Portugal
| | - Matilda Roziková
- Czech Metrology Institute , Okružní 31/772, 638 00 , Brno , Czech Republic
| | - Lisa Deleebeeck
- Danish Fundamental Metrology , Kogle Allé 5 2970 Hørsholm , Denmark
| | - Sune Veltzé
- Danish National Metrology Institute , Hørsholm , Denmark
| | - Teemu Näykki
- Suomen ympäristökeskus (SYKE) , Latokartanonkaari 11, 00790 Helsinki , Finland
| | - Frank Bastkowski
- Physikalisch-Technische Bundesanstalt , Bundesallee 100, 38116 Braunschweig , Germany
| | - Agnes Heering
- Physikalisch-Technische Bundesanstalt , Bundesallee 100, 38116 Braunschweig , Germany
| | - Nagy Dániel
- Metrological and Technical Supervisory Department of the Government Office of the Capital City Budapest (BFKH) , Németvölgyi út 37-39, 1124 Budapest , Hungary
| | - Raquel Quendera
- Instituto Português da Qualidade , Rua António Gião, 2, 2829-513 Caparica , Portugal
| | - Lokman Liv
- Electrochemistry Laboratory, Chemistry Group, The Scientific and Technological Research Council of Turkey - National Metrology Institute (TUBITAK UME) , Gebze , Kocaeli , 41470 , Turkey
| | - Emrah Uysal
- Electrochemistry Laboratory, Chemistry Group, The Scientific and Technological Research Council of Turkey - National Metrology Institute (TUBITAK UME) , Gebze , Kocaeli , 41470 , Turkey
| | - Nathan Lawrence
- ANBSensors , Unit 4, Penn Farm Studios, Haslingfield , Cambridge , CB23 1JZ , UK
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20
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Deleebeeck L, Snedden A, Nagy D, Szilágyi Nagyné Z, Roziková M, Vičarová M, Heering A, Bastkowski F, Leito I, Quendera R, Cabral V, Stoica D. Unified pH Measurements of Ethanol, Methanol, and Acetonitrile, and Their Mixtures with Water. SENSORS 2021; 21:s21113935. [PMID: 34200436 PMCID: PMC8201227 DOI: 10.3390/s21113935] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/27/2021] [Accepted: 06/02/2021] [Indexed: 11/16/2022]
Abstract
Measurement of pH in aqueous-organic mixtures with different compositions is of high importance in science and technology, but it is, at the same time, challenging both from a conceptual and practical standpoint. A big part of the difficulty comes from the fundamental incomparability of conventional pH values between solvents (spH, solvent-specific scales). The recent introduction of the unified pH (pHabs) concept opens up the possibility of measuring pH, expressed as pHabsH2O, in a way that is comparable between solvent, and, thereby, removing the conceptual problem. However, practical issues remain. This work presents the experience of the authors with measuring pHabsH2O values in mixtures of methanol, ethanol, and acetonitrile, with water, but without the presence of buffers or other additives. The aim was to assigned pHabsH2O values to solvent-water mixtures using differential potentiometry and the 'pHabs-ladder' method. Measurements were made of the potential difference between glass electrodes immersed in different solutions, separated by an ionic liquid salt bridge. Data were acquired for a series of solutions of varying solvent content. This work includes experiences related to: a selection of commercial electrodes, purity of starting material, and comparability between laboratories. Ranges of pHabsH2O values for selected compositions of solvent-water mixtures are presented.
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Affiliation(s)
- Lisa Deleebeeck
- DFM A/S, Kogle Allé 5, 2970 Hørsholm, Denmark;
- Correspondence:
| | | | - Dániel Nagy
- Government Office of the Capital City Budapest (BFKH), Németvölgyi út 37-39, 1124 Budapest, Hungary; (D.N.); (Z.S.N.)
| | - Zsófia Szilágyi Nagyné
- Government Office of the Capital City Budapest (BFKH), Németvölgyi út 37-39, 1124 Budapest, Hungary; (D.N.); (Z.S.N.)
| | - Matilda Roziková
- Czech Metrology Institute (CMI), Okružní 31, 63800 Brno, Czech Republic; (M.R.); (M.V.)
| | - Martina Vičarová
- Czech Metrology Institute (CMI), Okružní 31, 63800 Brno, Czech Republic; (M.R.); (M.V.)
- Faculty of Mechanical Engineering, Slovak University of Technology, Namestie Slobody 17, SK-81231 Bratislava 1, Slovakia
| | - Agnes Heering
- Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig, Germany; (A.H.); (F.B.)
- Institute of Chemistry, University of Tartu (UT), Ravila Street 14a, 50411 Tartu, Estonia;
| | - Frank Bastkowski
- Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig, Germany; (A.H.); (F.B.)
| | - Ivo Leito
- Institute of Chemistry, University of Tartu (UT), Ravila Street 14a, 50411 Tartu, Estonia;
| | - Raquel Quendera
- Instituto Português da Qualidade (IPQ), R. António Gião, 2, 2828-513 Caparica, Portugal; (R.Q.); (V.C.)
| | - Vítor Cabral
- Instituto Português da Qualidade (IPQ), R. António Gião, 2, 2828-513 Caparica, Portugal; (R.Q.); (V.C.)
| | - Daniela Stoica
- Laboratoire National de Metrologie et d’Essais (LNE), 1 rue Gaston Boissier, 75015 Paris, France;
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21
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Williams DBG, Bodachivskyi I. Comment on ‘Chitosan dissolution with sulfopropyl imidazolium Brønsted acidic ionic liquids’. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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22
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Marullo S, D'Anna F. Interplay of Acidity and Ionic Liquid Structure on the Outcome of a Heterocyclic Rearrangement Reaction. J Org Chem 2021; 86:4045-4052. [PMID: 33596066 DOI: 10.1021/acs.joc.0c02707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The study of suitable probe reactions is a powerful tool to investigate the properties of nonconventional solvents such ionic liquids (ILs). In particular, we studied the acid-catalyzed mononuclear rearrangement of heterocycles (MHR) of the Z-phenylhydrazone of 5-amino-3-benzoyl-1,2,4-oxadiazole into the relevant 1,2,3-triazole, in solution of ILs by means of kinetic measurements. We chose as solvents six ILs differing both in the cation and anion, in the presence of five carboxylic and sulfonic acids as catalysts. For a useful comparison, the reaction was also performed in 1,4-dioxane and methanol. In general, the reaction occurs faster in ILs, compared to conventional solvents, according to the weaker solvation interactions operating in the former media. The effect of IL anion and cation on the reactivity and on the acidic strength of the catalysts was analyzed. To this aim, we measured the acidic strength of the sulfonic acids in each IL, estimated by the equilibrium formation constant of each acid with 4-nitroaniline. We found that the trend of reactivity as a function of the IL anion mainly reflects the larger difference in acidic strengths of the catalyst. Conversely, acidic strength spans a narrower range as a function of the IL cation. As a result, other factors come into play, such as the π-π interactions involving aromatic IL cations, substrate, and transition states, leading to a more articulate trend.
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Affiliation(s)
- Salvatore Marullo
- Dipartimento di Scienze Biologiche, Chimiche e Farmaceutiche, Sezione di Chimica, Viale delle Scienze, Università degli Studi di Palermo, 90128 Palermo, Italy
| | - Francesca D'Anna
- Dipartimento di Scienze Biologiche, Chimiche e Farmaceutiche, Sezione di Chimica, Viale delle Scienze, Università degli Studi di Palermo, 90128 Palermo, Italy
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23
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Kotsyuda S, Wiesner A, Steinhauer S, Riedel S. Synthesis and Structural Characterization of Tetraalkylammonium Salts of the Weakly Coordinating Anion [Al(OTeF
5
)
4
]
–. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202000101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Sofiya Kotsyuda
- Anorganische Chemie, Institut für Chemie und Biologie Freie Universität Berlin Fabeckstr 34/36 14195 Berlin Germany
| | - Anja Wiesner
- Anorganische Chemie, Institut für Chemie und Biologie Freie Universität Berlin Fabeckstr 34/36 14195 Berlin Germany
| | - Simon Steinhauer
- Anorganische Chemie, Institut für Chemie und Biologie Freie Universität Berlin Fabeckstr 34/36 14195 Berlin Germany
| | - Sebastian Riedel
- Anorganische Chemie, Institut für Chemie und Biologie Freie Universität Berlin Fabeckstr 34/36 14195 Berlin Germany
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24
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Radtke V, Pütz K, Himmel D, Krossing I. The Inverted Philosopher’s Stone: how to turn silver to a base metal. J Solid State Electrochem 2020. [DOI: 10.1007/s10008-020-04633-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AbstractMetals often are classified as “noble” or “base”—characterizing their reduction potential as one of the most important chemical properties. We show that metals are only as noble as allowed by their environment, i.e. this is a relative term, and the “frame of reference” simply is the solvent in which the redox system is present. We prove that silver is a prime example for a noble metal that forfeits its noble character in the simple ionic liquid HMIM Br (1-hexyl-3-methylimidazolium bromide) as an example for such a solvent.
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25
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Beleh OM, Miller E, Toste FD, Miller SJ. Catalytic Dynamic Kinetic Resolutions in Tandem to Construct Two-Axis Terphenyl Atropisomers. J Am Chem Soc 2020; 142:16461-16470. [PMID: 32857500 DOI: 10.1021/jacs.0c08057] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The defined structure of molecules bearing multiple stereogenic axes is of increasing relevance to materials science, pharmaceuticals, and catalysis. However, catalytic enantioselective approaches to control multiple stereogenic axes remain synthetically challenging. We report the catalytic synthesis of two-axis terphenyl atropisomers, with complementary strategies to both chlorinated and brominated variants, formed with high diastereo- and enantioselectivity. The chemistry proceeds through a sequence of two distinct dynamic kinetic resolutions: first, an atroposelective ring opening of Bringmann-type lactones produces a product with one established axis of chirality, and second, a stereoselective arene halogenation delivers the product with the second axis of chirality established. In order to achieve these results, a class of Brønsted basic guanidinylated peptides, which catalyze an efficient atroposelective chlorination, is reported for the first time. In addition, a complementary bromination is reported, which also establishes the second stereogenic axis. These bromo-terphenyls are accessible following the discovery that chiral anion phase transfer catalysis by C2-symmetric phosphoric acids allows catalyst control in the second stereochemistry-determining event. Accordingly, we established the fully catalyst-controlled stereodivergent synthesis of all possible chlorinated stereoisomers while also demonstrating diastereodivergence in the brominated variants, with significant levels of enantioselectivity in all cases.
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Affiliation(s)
- Omar M Beleh
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Edward Miller
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - F Dean Toste
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Scott J Miller
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
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26
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Schorpp M, Heizmann T, Schmucker M, Rein S, Weber S, Krossing I. Synthesis and Application of a Perfluorinated Ammoniumyl Radical Cation as a Very Strong Deelectronator. Angew Chem Int Ed Engl 2020; 59:9453-9459. [PMID: 32187797 PMCID: PMC7317951 DOI: 10.1002/anie.202002768] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Indexed: 12/21/2022]
Abstract
The perfluorinated dihydrophenazine derivative (perfluoro-5,10-bis(perfluorophenyl)-5,10-dihydrophenazine) ("phenazineF ") can be easily transformed to a stable and weighable radical cation salt by deelectronation (i.e. oxidation) with Ag[Al(ORF )4 ]/ Br2 mixtures (RF =C(CF3 )3 ). As an innocent deelectronator it has a strong and fully reversible half-wave potential versus Fc+ /Fc in the coordinating solvent MeCN (E°'=1.21 V), but also in almost non-coordinating oDFB (=1,2-F2 C6 H4 ; E°'=1.29 V). It allows for the deelectronation of [FeIII Cp*2 ]+ to [FeIV (CO)Cp*2 ]2+ and [FeIV (CN-t Bu)Cp*2 ]2+ in common laboratory solvents and is compatible with good σ-donor ligands, such as L=trispyrazolylmethane, to generate novel [M(L)x ]n+ complex salts from the respective elemental metals.
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Affiliation(s)
- Marcel Schorpp
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Tim Heizmann
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Maximillian Schmucker
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Stephan Rein
- Institut für Physikalische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Stefan Weber
- Institut für Physikalische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
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27
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Schorpp M, Heizmann T, Schmucker M, Rein S, Weber S, Krossing I. Synthesis and Application of a Perfluorinated Ammoniumyl Radical Cation as a Very Strong Deelectronator. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202002768] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Marcel Schorpp
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF)Albert-Ludwigs-Universität Freiburg Albertstrasse 21 79104 Freiburg Germany
| | - Tim Heizmann
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF)Albert-Ludwigs-Universität Freiburg Albertstrasse 21 79104 Freiburg Germany
| | - Maximillian Schmucker
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF)Albert-Ludwigs-Universität Freiburg Albertstrasse 21 79104 Freiburg Germany
| | - Stephan Rein
- Institut für Physikalische ChemieAlbert-Ludwigs-Universität Freiburg Albertstrasse 21 79104 Freiburg Germany
| | - Stefan Weber
- Institut für Physikalische ChemieAlbert-Ludwigs-Universität Freiburg Albertstrasse 21 79104 Freiburg Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF)Albert-Ludwigs-Universität Freiburg Albertstrasse 21 79104 Freiburg Germany
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Xu J, Deng G, Wang YT, Guo HY, Kalhor P, Yu ZW. Local Acid Strength of Solutions and Its Quantitative Evaluation Using Excess Infrared Nitrile Probes. J Phys Chem Lett 2020; 11:1007-1012. [PMID: 31958952 DOI: 10.1021/acs.jpclett.9b03804] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We propose the concept of local acidity in condensed-phase chemistry in this work. The feature is demonstrated in trifluoroethanol (TFE) by employing two Fourier-transform infrared spectroscopy (FTIR) nitrile probes, acetonitrile (CH3CN) and benzonitrile (PhCN). Specifically, three positive excess peaks were found in the binary systems composed of TFE and a probe using excess spectroscopy. To characterize the local acidity quantitatively, we have tried to correlate the wavenumbers of the positive excess peaks of the probes and the pKa values in water of a series of XH-containing compounds (X = O, N, and C). Good linear relationships were discovered. Accordingly, three different pKa values of TFE were determined based on the three positive excess infrared peaks, which are attributed to the monomer, dimer, and trimer of TFE with the help of quantum-chemical calculations. The concept of local acidity and its quantitative evaluation enrich our knowledge of acid-base chemistry and will shed light on a better understanding of microstructures of solutions.
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Affiliation(s)
- Jing Xu
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry , Tsinghua University , Beijing 100084 , P. R. China
| | - Geng Deng
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry , Tsinghua University , Beijing 100084 , P. R. China
| | - Yu-Tian Wang
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry , Tsinghua University , Beijing 100084 , P. R. China
| | - Hao-Yue Guo
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry , Tsinghua University , Beijing 100084 , P. R. China
| | - Payam Kalhor
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry , Tsinghua University , Beijing 100084 , P. R. China
| | - Zhi-Wu Yu
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry , Tsinghua University , Beijing 100084 , P. R. China
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29
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Busca G, Gervasini A. Solid acids, surface acidity and heterogeneous acid catalysis. ADVANCES IN CATALYSIS 2020. [DOI: 10.1016/bs.acat.2020.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Kanzaki R, Kodamatani H, Tomiyasu T. Proton Thermodynamics in a Protic Ionic Liquid, Ethylammonium Nitrate. Chemistry 2019; 25:13500-13503. [PMID: 31454440 DOI: 10.1002/chem.201903485] [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: 07/30/2019] [Indexed: 11/11/2022]
Abstract
In order to investigate the proton solvation state in protic ionic liquids (PILs), ten acid dissociation enthalpies and entropies of eight compounds were determined in ethylammonium nitrate (EAN). Regardless of the nature of the compound, 24 kJ mol-1 larger enthalpy and 65 J mol-1 K-1 larger entropy than those in water, respectively, were observed. These values were reasonably explained by the differences in the proton solvation structure in EAN and water. Namely, protons in EAN exist as HNO3 , having a higher reaction energy than that of H3 O+ in water, undergo entropic stabilization as a result of the less-structured solvation. As such, the entropic effect of the proton solvation structure on the acid-base property is possibly applicable to all PILs. In addition, based on these proton thermodynamics, enthalpy and entropy windows were proposed as a novel perspective for the characterization of solvents. Use of this concept enabled the visualization of similarities and differences between EAN and water.
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Affiliation(s)
- Ryo Kanzaki
- Graduate School of Science and Engineering, Kagoshima University, 1-21-35, Korimoto, Kagoshima, 890-0065, Japan
| | - Hitoshi Kodamatani
- Graduate School of Science and Engineering, Kagoshima University, 1-21-35, Korimoto, Kagoshima, 890-0065, Japan
| | - Takashi Tomiyasu
- Graduate School of Science and Engineering, Kagoshima University, 1-21-35, Korimoto, Kagoshima, 890-0065, Japan
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31
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Pliego JR, Riveros JM. Hybrid discrete‐continuum solvation methods. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2019. [DOI: 10.1002/wcms.1440] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Josefredo R. Pliego
- Departamento de Ciências Naturais Universidade Federal de São João del‐Rei São João del‐Rei Brazil
| | - Jose M. Riveros
- Departamento de Química Fundamental Instituto de Química, Universidade de São Paulo São Paulo Brazil
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32
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Kahlert H, Leito I. Generalization of Acid-Base Diagrams Based on the Unified pH-Scale. Chemphyschem 2019; 20:1779-1785. [PMID: 31087622 PMCID: PMC7003793 DOI: 10.1002/cphc.201900388] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/13/2019] [Indexed: 11/13/2022]
Abstract
So far, pH‐lgci diagrams have been exclusively used for the theoretical description of acid‐base equilibria in aqueous solutions. Here, this approach is extended to include acid‐base equilibria in nonaqueous non‐hydrogen‐bond‐donor (non‐HBD) solvents following the acid‐base theory of Brønsted and Lowry, and using a unified pH scale (pHabs scale). This way, it is possible to estimate the approximate concentrations of all the species involved in acid‐base equilibria in a solution at any solution acidity pH(HS)
, and vice versa. The diagrams are excellent to illustrate the differences in behavior of species involved in the solution equilibria in different solvents, for example, an aqueous solution of acetic acid is an acidic solution; however, the same concentration of acetic acid in DMSO has a pHabsH2O
value of about 10.6, that is, it is a basic solution with reference to the aqueous pH scale.
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Affiliation(s)
- Heike Kahlert
- Institute of Biochemistry, University of Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| | - Ivo Leito
- Institute of Chemistry, University of Tartu, Ravila 14a, 50411, Tartu, Eesti
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34
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Blasius J, Ingenmey J, Perlt E, von Domaros M, Hollóczki O, Kirchner B. Predicting Mole-Fraction-Dependent Dissociation for Weak Acids. Angew Chem Int Ed Engl 2019; 58:3212-3216. [PMID: 30589171 DOI: 10.1002/anie.201811839] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/12/2018] [Indexed: 11/10/2022]
Abstract
We demonstrate for formic and acetic acid dissolved in water as examples that the binary quantum cluster equilibrium (bQCE) approach can predict acid strengths over the whole range of acid concentrations. The acid strength increases in a complex rather than a simple way with increasing mole fraction of the acid from 0 to 0.7, reflecting the complex interplay between the dissociated ions or conjugate bases available as compared to the acid and water molecules. Furthermore, our calculated ion concentrations meet the experimental maximum of the conductivity with excellent agreement for acetic acid and satisfactorily for the formic acid/water mixture. As only a limited number of simple quantum-chemical calculations are required for the prediction, bQCE is clearly a valuable approach to access these quantities also in non-aqueous solutions. It is a highly valuable asset for predicting ionization processes in highly concentrated solutions, which are relevant for biological and chemical systems, as well as technological processes.
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Affiliation(s)
- Jan Blasius
- Mulliken Center for Theoretical Chemistry, Universität Bonn, Beringstr. 4, 53115, Bonn, Germany
| | - Johannes Ingenmey
- Mulliken Center for Theoretical Chemistry, Universität Bonn, Beringstr. 4, 53115, Bonn, Germany
| | - Eva Perlt
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, Irvine, CA, 92697, USA
| | - Michael von Domaros
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, Irvine, CA, 92697, USA
| | - Oldamur Hollóczki
- Mulliken Center for Theoretical Chemistry, Universität Bonn, Beringstr. 4, 53115, Bonn, Germany
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Universität Bonn, Beringstr. 4, 53115, Bonn, Germany
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35
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Blasius J, Ingenmey J, Perlt E, von Domaros M, Hollóczki O, Kirchner B. Dissoziation schwacher Säuren über den gesamten Molenbruchbereich. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201811839] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Jan Blasius
- Mulliken Center for Theoretical ChemistryUniversität Bonn Beringstraße 4 53115 Bonn Deutschland
| | - Johannes Ingenmey
- Mulliken Center for Theoretical ChemistryUniversität Bonn Beringstraße 4 53115 Bonn Deutschland
| | - Eva Perlt
- Department of Chemistry, 1102Natural Sciences IIUniversity of California, Irvine Irvine CA 92697 USA
| | - Michael von Domaros
- Department of Chemistry, 1102Natural Sciences IIUniversity of California, Irvine Irvine CA 92697 USA
| | - Oldamur Hollóczki
- Mulliken Center for Theoretical ChemistryUniversität Bonn Beringstraße 4 53115 Bonn Deutschland
| | - Barbara Kirchner
- Mulliken Center for Theoretical ChemistryUniversität Bonn Beringstraße 4 53115 Bonn Deutschland
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36
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Bodachivskyi I, Kuzhiumparambil U, Williams DBG. The role of the molecular formula of ZnCl2·nH2O on its catalyst activity: a systematic study of zinc chloride hydrates in the catalytic valorisation of cellulosic biomass. Catal Sci Technol 2019. [DOI: 10.1039/c9cy00846b] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We show the efficient and direct transformation of a range of low value cellulosic substrates such as lignocellulose and algal biomass, into higher value chemicals, including low molecular weight reducing saccharides and furanoid products.
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Affiliation(s)
- Iurii Bodachivskyi
- School of Mathematical and Physical Sciences
- University of Technology Sydney
- Sydney
- Australia
| | | | - D. Bradley G. Williams
- School of Mathematical and Physical Sciences
- University of Technology Sydney
- Sydney
- Australia
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37
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Hazin K, Patrick BO, Gates DP. Ammonium and Potassium Salts of a Hexacoordinate Phosphorus(V) Anion Featuring P–O and P–C Bonds. Inorg Chem 2018; 58:188-198. [DOI: 10.1021/acs.inorgchem.8b02174] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Khatera Hazin
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Brian O. Patrick
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Derek P. Gates
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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38
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Kanzaki R, Daiba H, Kodamatani H, Tomiyasu T. Validation of pH Standards and Estimation of the Activity Coefficients of Hydrogen and Chloride Ions in an Ionic Liquid, Ethylammonium Nitrate. J Phys Chem B 2018; 122:10593-10599. [PMID: 30351941 DOI: 10.1021/acs.jpcb.8b08870] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We selected and validated the pH values of three standard materials that function in the protic ionic liquid, ethylammonium nitrate (EAN). The pH values of 0.05 mol kg-1 phthalate, oxalate, and phosphate buffers were 4.93 (0.04), 2.12 (0.04), and 7.13 (0.06), respectively (the values in the parentheses denote the standard deviation). Because the pH of EAN ranges from 0 to 10, with a neutral pH of 5, these materials are usable as acidic, basic, or neutral standards. The standard electrode potential of silver-silver chloride in EAN was 127.2 (1.7) mV. The activity coefficients of hydrogen and chloride ions remain equal to unity in EAN of a wide concentration range, which indicates that the effective ionic strength is independent of the solute ion concentration. In addition, the estimated value of the transfer activity coefficient of chloride ion suggests a weaker solvation in EAN compared with water in spite of a ubiquitous cation (C2H5NH3+). These behaviors of ions in EAN can be explained by the unique solvation in the ionic liquid through direct ion-ion electrostatic interactions.
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Affiliation(s)
- Ryo Kanzaki
- Department of Earth and Environmental Sciences, Graduate School of Science and Engineering , Kagoshima University , Korimoto, Kagoshima 890-0065 , Japan
| | - Hikaru Daiba
- Department of Earth and Environmental Sciences, Graduate School of Science and Engineering , Kagoshima University , Korimoto, Kagoshima 890-0065 , Japan
| | - Hitoshi Kodamatani
- Department of Earth and Environmental Sciences, Graduate School of Science and Engineering , Kagoshima University , Korimoto, Kagoshima 890-0065 , Japan
| | - Takashi Tomiyasu
- Department of Earth and Environmental Sciences, Graduate School of Science and Engineering , Kagoshima University , Korimoto, Kagoshima 890-0065 , Japan
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39
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Greb L. Lewis Superacids: Classifications, Candidates, and Applications. Chemistry 2018; 24:17881-17896. [DOI: 10.1002/chem.201802698] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Lutz Greb
- Anorganisch-Chemisches InstitutUniversität Heidelberg Im Neuenheimer Feld 270 Germany
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40
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Montero-Campillo MM, Alkorta I, Elguero J. Enhancement of Thermodynamic Gas-Phase Acidity and Basicity of Water by Means of Secondary Interactions. Chemphyschem 2018; 19:2486-2491. [PMID: 29944196 DOI: 10.1002/cphc.201800518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Indexed: 11/07/2022]
Abstract
A series of A⋅water, B⋅water complexes (A=acid, B=base) are studied at the G4 level of theory to show that water acidity or basicity can be modulated by non-covalent interactions. Protic and non-protic acids interacting with water form hydrogen bonds or other kinds of non-covalent interactions, respectively, that may dramatically change the acidity of water up to almost 360 kJ ⋅ mol-1 in terms of enthalpy. Similarly, hydrogen bonds responsible for the interaction between typical small nitrogen-containing Lewis bases and water can enhance the proton affinity of water by almost 300 kJ ⋅ mol-1 . Our results reveal that these large enhancements are linearly related with the binding energy of the charged complexes, and are determined by the Lewis acid-base properties of the molecule involved in the interaction, allowing a quite precise modulation of the corresponding acid-base properties of water.
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Affiliation(s)
- M Merced Montero-Campillo
- Departamento de Química, Módulo 13, Facultad de Ciencias and Institute of Advanced Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC, Cantoblanco, E-28049, Madrid, Spain
| | - Ibon Alkorta
- Instituto de Química Médica, CSIC, Juan de la Cierva, 3, E-28006, Madrid, Spain
| | - José Elguero
- Instituto de Química Médica, CSIC, Juan de la Cierva, 3, E-28006, Madrid, Spain
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