Characterization of the acidity and basicity of green solvents by NMR techniques
The acidity and basicity of the solvents can influence the reaction outcome notably, and hence the precise measurement of pH is important for reaction. However, not all the pH values of organic solvents can be determined with a classic pH meter straightly. In this research, the acidity and basicity...
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| Format: | Article |
| Language: | English |
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KeAi Communications Co. Ltd.
2021-08-01
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| Series: | Magnetic Resonance Letters |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2772516221000012 |
| _version_ | 1811292264414052352 |
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| author | Kemeng Shi Christian Marcus Pedersen Hui Chang Jing Shi Yingxiong Wang Yan Qiao |
| author_facet | Kemeng Shi Christian Marcus Pedersen Hui Chang Jing Shi Yingxiong Wang Yan Qiao |
| author_sort | Kemeng Shi |
| collection | DOAJ |
| description | The acidity and basicity of the solvents can influence the reaction outcome notably, and hence the precise measurement of pH is important for reaction. However, not all the pH values of organic solvents can be determined with a classic pH meter straightly. In this research, the acidity and basicity of environmentally friendly green solvents, such as ZnCl2 molten salt hydrate, ionic liquids (ILs) and deep eutectic solvents (DESs), were characterized by 31P and 1H NMR spectroscopy using trimethylphosphine oxide (TMPO) and pyrrole as probe molecules at 298 K. For the ZnCl2 molten salt hydrate, the acidic strength of the ZnCl2 molten salt hydrate increased with the concentration of ZnCl2. By using the 1H-pyrrole NMR approach, it was found that the base strength of amino acid-based ILs follows the order: [Ch][Lys] > [Ch][His]. |
| first_indexed | 2024-04-13T04:42:49Z |
| format | Article |
| id | doaj.art-e34fdc46650a445997872a9e786c84cd |
| institution | Directory Open Access Journal |
| issn | 2772-5162 |
| language | English |
| last_indexed | 2024-04-13T04:42:49Z |
| publishDate | 2021-08-01 |
| publisher | KeAi Communications Co. Ltd. |
| record_format | Article |
| series | Magnetic Resonance Letters |
| spelling | doaj.art-e34fdc46650a445997872a9e786c84cd2022-12-22T03:01:57ZengKeAi Communications Co. Ltd.Magnetic Resonance Letters2772-51622021-08-01118188Characterization of the acidity and basicity of green solvents by NMR techniquesKemeng Shi0Christian Marcus Pedersen1Hui Chang2Jing Shi3Yingxiong Wang4Yan Qiao5Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, ChinaDepartment of Chemistry, University of Copenhagen, DK-2100 Copenhagen, DenmarkSinopec Shanghai Petrochemical Co., Ltd., Shanghai, 200540, ChinaInstitute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, ChinaInstitute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China; Corresponding authors.Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China; Corresponding authors.The acidity and basicity of the solvents can influence the reaction outcome notably, and hence the precise measurement of pH is important for reaction. However, not all the pH values of organic solvents can be determined with a classic pH meter straightly. In this research, the acidity and basicity of environmentally friendly green solvents, such as ZnCl2 molten salt hydrate, ionic liquids (ILs) and deep eutectic solvents (DESs), were characterized by 31P and 1H NMR spectroscopy using trimethylphosphine oxide (TMPO) and pyrrole as probe molecules at 298 K. For the ZnCl2 molten salt hydrate, the acidic strength of the ZnCl2 molten salt hydrate increased with the concentration of ZnCl2. By using the 1H-pyrrole NMR approach, it was found that the base strength of amino acid-based ILs follows the order: [Ch][Lys] > [Ch][His].http://www.sciencedirect.com/science/article/pii/S2772516221000012Green solventsAcidityBasicity31P-TMPO NMR1H-pyrrole NMR |
| spellingShingle | Kemeng Shi Christian Marcus Pedersen Hui Chang Jing Shi Yingxiong Wang Yan Qiao Characterization of the acidity and basicity of green solvents by NMR techniques Magnetic Resonance Letters Green solvents Acidity Basicity 31P-TMPO NMR 1H-pyrrole NMR |
| title | Characterization of the acidity and basicity of green solvents by NMR techniques |
| title_full | Characterization of the acidity and basicity of green solvents by NMR techniques |
| title_fullStr | Characterization of the acidity and basicity of green solvents by NMR techniques |
| title_full_unstemmed | Characterization of the acidity and basicity of green solvents by NMR techniques |
| title_short | Characterization of the acidity and basicity of green solvents by NMR techniques |
| title_sort | characterization of the acidity and basicity of green solvents by nmr techniques |
| topic | Green solvents Acidity Basicity 31P-TMPO NMR 1H-pyrrole NMR |
| url | http://www.sciencedirect.com/science/article/pii/S2772516221000012 |
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