1
|
Du MX, Han LX, Wang SR, Xu KJ, Zhu WR, Qiao X, Liu CY. Solvent Effects on the 1 H-NMR Chemical Shifts of Imidazolium-Based Ionic Liquids. Chemphyschem 2023; 24:e202300292. [PMID: 37491736 DOI: 10.1002/cphc.202300292] [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: 04/24/2023] [Revised: 07/22/2023] [Accepted: 07/25/2023] [Indexed: 07/27/2023]
Abstract
The 1 H nuclear magnetic resonance (1 H-NMR) spectrum is a useful tool for characterizing the hydrogen bonding (H-bonding) interactions in ionic liquids (ILs). As the main hydrogen bond (H-bond) donor of imidazolium-based ILs, the chemical shift (δH2 ) of the proton in the 2-position of the imidazolium ring (H2) exhibits significant and complex solvents, concentrations and anions dependence. In the present work, based on the dielectric constants (ϵ) and Kamlet-Taft (KT) parameters of solvents, we identified that the δH2 are dominated by the solvents polarity and the competitive H-bonding interactions between cations and anions or solvents. Besides, the solvents effects on δH2 are understood by the structure of ILs in solvents: 1) In diluted solutions of inoizable solvents, ILs exist as free ions and the cations will form H-bond with solvents, resulting in δH2 being independent with anions but positively correlated with βS . 2) In diluted solutions of non-ionzable solvents, ILs exist as contact ion-pairs (CIPs) and H2 will form H-bond with anions. Since non-ionizable solvents hardly influence the H-bonding interactions between H2 and anions, the δH2 are not related to βS but positively correlated with βIL .
Collapse
Affiliation(s)
- Ming-Xuan Du
- Department CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 10049, China
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Lin-Xue Han
- Department CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 10049, China
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Shi-Rong Wang
- Department CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 10049, China
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Kuang-Jie Xu
- Department CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 10049, China
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Wen-Rui Zhu
- Department CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 10049, China
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Xin Qiao
- Department CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Chen-Yang Liu
- Department CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 10049, China
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| |
Collapse
|
2
|
Synthesis, Characterization, Biological Evaluation, and In Silico Studies of Imidazolium-, Pyridinium-, and Ammonium-Based Ionic Liquids Containing n-Butyl Side Chains. Molecules 2022; 27:molecules27196650. [PMID: 36235187 PMCID: PMC9572234 DOI: 10.3390/molecules27196650] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/23/2022] [Accepted: 09/26/2022] [Indexed: 11/17/2022] Open
Abstract
Ionic liquids (ILs) have emerged as active pharmaceutical ingredients because of their excellent antibacterial and biological activities. Herein, we used the green-chemistry-synthesis procedure, also known as the metathesis method, to develop three series of ionic liquids using 1-methyl-3-butyl imidazolium, butyl pyridinium, and diethyldibutylammonium as cations, and bromide (Br−), methanesulfonate (CH3SO3−), bis(trifluoromethanesulfonyl)imide (NTf2−), dichloroacetate (CHCl2CO2−), tetrafluoroborate (BF4−), and hydrogen sulfate (HSO4−) as anions. Spectroscopic methods were used to validate the structures of the lab-synthesized ILs. We performed an agar well diffusion assay by using pathogenic bacteria that cause various infections (Escherichia coli; Enterobacter aerogenes; Klebsiella pneumoniae; Proteus vulgaris; Pseudomonas aeruginosa; Streptococcus pneumoniae; Streptococcus pyogenes) to scrutinize the in vitro antibacterial activity of the ILs. It was established that the nature and unique combination of the cations and anions were responsible for the antibacterial activity of the ILs. Among the tested ionic liquids, the imidazolium cation and NTf2− and HSO4− anions exhibited the highest antibacterial activity. The antibacterial potential was further investigated by in silico studies, and it was observed that bis(trifluoromethanesulfonyl)imide (NTf2−) containing imidazolium and pyridinium ionic liquids showed the maximum inhibition against the targeted bacterial strains and could be utilized in antibiotics. These antibacterial activities float the ILs as a promising alternative to the existing antibiotics and antiseptics.
Collapse
|
3
|
Damodaran K. Recent advances in NMR spectroscopy of ionic liquids. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 129:1-27. [PMID: 35292132 DOI: 10.1016/j.pnmrs.2021.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 12/17/2021] [Accepted: 12/28/2021] [Indexed: 06/14/2023]
Abstract
This review presents recent developments in the application of NMR spectroscopic techniques in the study of ionic liquids. NMR has been the primary tool not only for the structural characterization of ionic liquids, but also for the study of dynamics. The presence of a host of NMR active nuclei in ionic liquids permits widespread use of multinuclear NMR experiments. Chemical shifts and multinuclear coupling constants are used routinely for the structure elucidation of ionic liquids and of products formed by their covalent interactions with other materials. Also, the availability of a multitude of NMR techniques has facilitated the study of dynamical processes in them. These include the use of NOESY to study inter-ionic interactions, pulsed-field gradient techniques for probing transport properties, and relaxation measurements to elucidate rotational dynamics. This review will focus on the application of each of these techniques to investigate ionic liquids.
Collapse
Affiliation(s)
- Krishnan Damodaran
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
| |
Collapse
|
4
|
Lengvinaitė D, Kvedaraviciute S, Bielskutė S, Klimavicius V, Balevicius V, Mocci F, Laaksonen A, Aidas K. Structural Features of the [C4mim][Cl] Ionic Liquid and Its Mixtures with Water: Insight from a 1H NMR Experimental and QM/MD Study. J Phys Chem B 2021; 125:13255-13266. [PMID: 34806880 PMCID: PMC8667039 DOI: 10.1021/acs.jpcb.1c08215] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/09/2021] [Indexed: 01/05/2023]
Abstract
The 1H NMR chemical shift of water exhibits non-monotonic dependence on the composition of an aqueous mixture of 1-butyl-3-methylimidazolium chloride, [C4mim][Cl], ionic liquid (IL). A clear minimum is observed for the 1H NMR chemical shift at a molar fraction of the IL of 0.34. To scrutinize the molecular mechanism behind this phenomenon, extensive classical molecular dynamics simulations of [C4mim][Cl] IL and its mixtures with water were carried out. A combined quantum mechanics/molecular mechanics approach based on the density functional theory was applied to predict the NMR chemical shifts. The proliferation of strongly hydrogen-bonded complexes between chloride anions and water molecules is found to be the reason behind the increasing 1H NMR chemical shift of water when its molar fraction in the mixture is low and decreasing. The model shows that the chemical shift of water molecules that are trapped in the IL matrix without direct hydrogen bonding to the anions is considerably smaller than the 1H NMR chemical shift predicted for the neat water. The structural features of neat IL and its mixtures with water have also been analyzed in relation to their NMR properties. The 1H NMR spectrum of neat [C4mim][Cl] was predicted and found to be in very reasonable agreement with the experimental data. Finally, the experimentally observed strong dependence of the chemical shift of the proton at position 2 in the imidazolium ring on the composition of the mixture was rationalized.
Collapse
Affiliation(s)
- Dovilė Lengvinaitė
- Institute
of Chemical Physics, Faculty of Physics, Vilnius University, Vilnius LT-10257, Lithuania
| | | | - Stasė Bielskutė
- Institute
of Chemical Physics, Faculty of Physics, Vilnius University, Vilnius LT-10257, Lithuania
| | - Vytautas Klimavicius
- Institute
of Chemical Physics, Faculty of Physics, Vilnius University, Vilnius LT-10257, Lithuania
| | - Vytautas Balevicius
- Institute
of Chemical Physics, Faculty of Physics, Vilnius University, Vilnius LT-10257, Lithuania
| | - Francesca Mocci
- Università
di Cagliari, Dipartimento di Scienze Chimiche e Geologiche, Cittadella
Universitaria di Monserrato, Cagliari I-09042, Monserrato, Italy
| | - Aatto Laaksonen
- Energy Engineering,
Division of Energy Science, Luleå
University of Technology, Luleå 97181, Sweden
- Division
of Physical Chemistry, Department of Materials and Environmental Chemistry,
Arrhenius Laboratory, Stockholm University, Stockholm 10691, Sweden
- Center of
Advanced Research in Bionanoconjugates and Biopolymers, “Petru Poni” Institute of Macromolecular
Chemistry, Iasi 700469, Romania
- State
Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Kęstutis Aidas
- Institute
of Chemical Physics, Faculty of Physics, Vilnius University, Vilnius LT-10257, Lithuania
| |
Collapse
|
5
|
Sutar Y, Fulton SR, Paul S, Altamirano S, Mhatre S, Saeed H, Patel P, Mallick S, Bhat R, Patravale VB, Chauhan H, Nielsen K, Date AA. Docusate-Based Ionic Liquids of Anthelmintic Benzimidazoles Show Improved Pharmaceutical Processability, Lipid Solubility, and in Vitro Activity against Cryptococcus neoformans. ACS Infect Dis 2021; 7:2637-2649. [PMID: 34467755 PMCID: PMC8884109 DOI: 10.1021/acsinfecdis.1c00063] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
As the existing therapeutic modalities for the treatment of cryptococcal meningitis (CM) have suboptimal efficacy, repurposing existing drugs for the treatment of CM is of great interest. The FDA-approved anthelmintic benzimidazoles, albendazole, mebendazole, and flubendazole, have demonstrated potent but variable in vitro activity against Cryptococcus neoformans, the predominant fungal species responsible for CM. We performed molecular docking studies to ascertain the interaction of albendazole, mebendazole, and flubendazole with a C. neoformans β-tubulin structure, which revealed differential binding interactions and explained the different in vitro efficacies reported previously and observed in this investigation. Despite their promising in vitro efficacy, the repurposing of anthelmintic benzimidazoles for oral CM therapy is significantly hampered due to their high crystallinity, poor pharmaceutical processability, low and pH-dependent solubility, and drug precipitation upon entering the intestine, all of which result in low and variable oral bioavailability. Here, we demonstrate that the anthelmintic benzimidazoles can be transformed into partially amorphous low-melting ionic liquids (ILs) with a simple metathesis reaction using amphiphilic sodium docusate as a counterion. In vitro efficacy studies on a laboratory reference and a clinical isolate of C. neoformans showed 2- to 4-fold lower IC90 values for docusate-based ILs compared to the pure anthelmintic benzimidazoles. Furthermore, using a C. neoformans strain with green fluorescent protein (GFP)-tagged β-tubulin and albendazole and its docusate IL as model candidates, we showed that the benzimidazoles and their ILs reduce the viability of C. neoformans by interfering with its microtubule assembly. Unlike pure anthelmintic benzimidazoles, the docusate-based ILs showed excellent solubility in organic solvents and >30-fold higher solubility in bioavailability-enhancing lipid vehicles. Finally, the docusate ILs were successfully incorporated into SoluPlus, a self-assembling biodegradable polymer, which upon dilution with water formed polymeric micelles with a size of <100 nm. Thus, the development of docusate-based ILs represents an effective approach to improve the physicochemical properties and potency of anthelmintic benzimidazoles to facilitate their repurposing and preclinical development for CM therapy.
Collapse
Affiliation(s)
- Yogesh Sutar
- Department of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo, Hilo, Hawaii 96720, United States
| | - Sophie R Fulton
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sagarkumar Paul
- Department of Pharmaceutical Sciences, Creighton University School of Pharmacy and Health Profession, 2200 California Plaza, Omaha, Nebraska 68710, United States
| | - Sophie Altamirano
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Susmit Mhatre
- Department of Pharmaceutical Sciences, Institute of Chemical Technology, N.P Marg, Matunga, Mumbai, Maharashtra 400011, India
| | - Hiwa Saeed
- Department of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo, Hilo, Hawaii 96720, United States
| | - Pratikkumar Patel
- Department of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo, Hilo, Hawaii 96720, United States
| | - Sudipta Mallick
- Department of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo, Hilo, Hawaii 96720, United States
| | - Roopal Bhat
- Department of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo, Hilo, Hawaii 96720, United States
- Department of Pharmaceutics, Shree Chanakya Education Society's Indira College of Pharmacy, Tathawade, Pune, Maharashtra 411033, India
| | - Vandana B Patravale
- Department of Pharmaceutical Sciences, Institute of Chemical Technology, N.P Marg, Matunga, Mumbai, Maharashtra 400011, India
| | - Harsh Chauhan
- Department of Pharmaceutical Sciences, Creighton University School of Pharmacy and Health Profession, 2200 California Plaza, Omaha, Nebraska 68710, United States
| | - Kirsten Nielsen
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Abhijit A Date
- Department of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo, Hilo, Hawaii 96720, United States
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii Manoa, Honolulu, Hawaii 96813, United States
| |
Collapse
|
6
|
Saeed HK, Sutar Y, Patel P, Bhat R, Mallick S, Hatada AE, Koomoa DLT, Lange I, Date AA. Synthesis and Characterization of Lipophilic Salts of Metformin to Improve Its Repurposing for Cancer Therapy. ACS OMEGA 2021; 6:2626-2637. [PMID: 33553880 PMCID: PMC7859945 DOI: 10.1021/acsomega.0c04779] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 01/14/2021] [Indexed: 06/12/2023]
Abstract
Epidemiological evidence has accentuated the repurposing of metformin hydrochloride for cancer treatment. However, the extreme hydrophilicity and poor permeability of metformin hydrochloride are responsible for its poor anticancer activity in vitro and in vivo. Here, we report the synthesis and characterization of several lipophilic metformin salts containing bulky anionic permeation enhancers such as caprate, laurate, oleate, cholate, and docusate as counterions. Of various counterions tested, only docusate was able to significantly improve the lipophilicity and lipid solubility of metformin. To evaluate the impact of the association of anionic permeation enhancers with metformin, we checked the in vitro anticancer activity of various lipophilic salts of metformin using drug-sensitive (MYCN-2) and drug-resistant (SK-N-Be2c) neuroblastoma cells as model cancer cells. Metformin hydrochloride showed a very low potency (IC50 ≈ >100 mM) against MYCN-2 and SK-N-Be2c cells. Anionic permeation enhancers showed a considerably higher activity (IC50 ≈ 125 μM to 1.6 mM) against MYCN-2 and SK-N-Be2c cells than metformin. The association of metformin with most of the bulky anionic agents negatively impacted the anticancer activity against MYCN-2 and SK-N-Be2c cells. However, metformin docusate showed 700- to 4300-fold improvement in anticancer potency compared to metformin hydrochloride and four- to five-fold higher in vitro anticancer activity compared to sodium docusate, indicating a synergistic association between metformin and docusate. A similar trend was observed when we tested the in vitro activity of metformin docusate, sodium docusate, and metformin hydrochloride against hepatocellular carcinoma (HepG2) and triple-negative breast cancer (MDA-MB-231) cells.
Collapse
Affiliation(s)
- Hiwa K. Saeed
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
| | - Yogesh Sutar
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
| | - Pratikkumar Patel
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
| | - Roopal Bhat
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
- Department
of Pharmaceutics, Shree Chanakya Education
Society’s Indira College of Pharmacy, Tathawade, Pune, Maharashtra 411033, India
| | - Sudipta Mallick
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
| | - Alyssa E. Hatada
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
| | - Dana-Lynn T. Koomoa
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
| | - Ingo Lange
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
| | - Abhijit A. Date
- Department
of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai’i at Hilo, Hilo Hawaii 96720, United States
| |
Collapse
|
7
|
NMR Parameters of Imidazolium Ionic Liquids as Indicators of Their State and Properties in Aqueous Solutions. J SOLUTION CHEM 2020. [DOI: 10.1007/s10953-020-01044-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
8
|
Gaur A, Avula NVS, Balasubramanian S. Insights into the Stabilization of Fluoride Ions in Ionic Liquids: Pointers to Better Fluorinating Agents. J Phys Chem B 2020; 124:8844-8856. [PMID: 32930587 DOI: 10.1021/acs.jpcb.0c04939] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The fluorination efficiency of a fluorinating agent depends on the free availability of the fluoride ions, which in turn depends on its interaction with its solvation shell. A stable fluoride-based poor solvate ionic liquid (SIL) comprising 1-ethyl-3-methylimidazolium (EMIM) cation and ethylene glycol (EG) was recently reported and demonstrated as a fluorinating agent. Herein, we performed ab initio calculations and ab initio molecular dynamics simulations to gain a microscopic understanding of the intermolecular interactions in this SIL in gas, liquid, and crystalline phases. Ethylene glycol (EG), being capable of forming hydrogen bond(s) with the fluoride ion, prevents the latter from reacting with the EMIM cation. Fluoride forms hydrogen bonds with both the cation and the EG molecule, but it was found to have more affinity toward EG, forming a stronger hydrogen bond with its hydroxyl proton than with the acidic proton of the cation. An optimal concentration of EG in the SIL balances its contribution to stabilizing the fluoride ion and yet making fluoride available for fluorination.
Collapse
Affiliation(s)
- Anjali Gaur
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560 064, India
| | - Nikhil V S Avula
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560 064, India
| | - Sundaram Balasubramanian
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560 064, India
| |
Collapse
|
9
|
Bryant N, G. Yoo C, Pu Y, Ragauskas AJ. 2D HSQC Chemical Shifts of Impurities from Biomass Pretreatment. ChemistrySelect 2020. [DOI: 10.1002/slct.202000406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Nathan Bryant
- Department of Chemical and Biomolecular Engineering University of Tennessee Knoxville 37916 USA
| | - Chang G. Yoo
- Department of Paper and Bioprocess Engineering State University of New York College of Environmental Science and Forestry Syracuse NY 13210 USA
| | - Yunqiao Pu
- Center for Bioenergy Innovation, Biosciences Division University of Tennessee-Oak Ridge National Laboratory Joint Institute for Biological Science, Oak Ridge National Laboratory Oak Ridge TN 37831 USA
| | - Arthur J. Ragauskas
- Department of Chemical and Biomolecular Engineering University of Tennessee Knoxville 37916 USA
- Center for Bioenergy Innovation, Biosciences Division University of Tennessee-Oak Ridge National Laboratory Joint Institute for Biological Science, Oak Ridge National Laboratory Oak Ridge TN 37831 USA
- Center for Renewable Carbon, Department of Forestry, Wildlife, and Fisheries University of Tennessee Institute of Agriculture Knoxville TN 37996 USA
| |
Collapse
|
10
|
Guschlbauer J, Vollgraff T, Sundermeyer J. Systematic study on anion–cation interactions via doubly ionic H-bonds in 1,3-dimethylimidazolium salts comprising chalcogenolate anions MMIm [ER] (E = S, Se; R = H, tBu, SiMe3). Dalton Trans 2019; 48:10971-10978. [DOI: 10.1039/c9dt01586h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We present convenient syntheses of so far inaccessible, crystalline and highly pure 1,3-dialkylimidazolium salts with extremely nucleophilic thiolate and selenolate anions [ER]− (R = H, tBu, SiMe3).
Collapse
Affiliation(s)
- Jannick Guschlbauer
- Fachbereich Chemie and Materials Science Center
- Philipps-Universität Marburg
- 35043 Marburg
- Germany
| | - Tobias Vollgraff
- Fachbereich Chemie and Materials Science Center
- Philipps-Universität Marburg
- 35043 Marburg
- Germany
| | - Jörg Sundermeyer
- Fachbereich Chemie and Materials Science Center
- Philipps-Universität Marburg
- 35043 Marburg
- Germany
| |
Collapse
|