Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies
Chemoselective photoredox fluorination is an appealing approach to access fluorinated fine chemicals such as active pharmaceutical ingredients, but most of the known procedures currently lack time-resolved mechanistic insights. We use nanosecond transient absorption spectroscopy and density function...
| Main Authors: | , , , , , |
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| Format: | Journal Article |
| Language: | English |
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2018
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| Online Access: | https://hdl.handle.net/10356/87664 http://hdl.handle.net/10220/47035 |
| _version_ | 1811688582174212096 |
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| author | Kee, J. W. Shao, H. Kee, C. W. Lu, Yunpeng Soo, Han Sen Tan, Choon Hong |
| author2 | School of Physical and Mathematical Sciences |
| author_facet | School of Physical and Mathematical Sciences Kee, J. W. Shao, H. Kee, C. W. Lu, Yunpeng Soo, Han Sen Tan, Choon Hong |
| author_sort | Kee, J. W. |
| collection | NTU |
| description | Chemoselective photoredox fluorination is an appealing approach to access fluorinated fine chemicals such as active pharmaceutical ingredients, but most of the known procedures currently lack time-resolved mechanistic insights. We use nanosecond transient absorption spectroscopy and density functional theory (DFT) calculations to elucidate the elementary steps after irradiation in a photocatalytic fluorination procedure that we reported previously. Time-resolved optical spectroscopy suggests that direct reaction only occurs between the photoexcited anthraquinone (AQN) and Selectfluor®. We have observed spectroscopic evidence of a novel transient AQN–Selectfluor® species for the first time. Further studies by DFT calculations suggest that the AQN–Selectfluor® triplet exciplex formed by photoirradiation is responsible for initiating and sustaining the fluorination reaction. |
| first_indexed | 2024-10-01T05:34:30Z |
| format | Journal Article |
| id | ntu-10356/87664 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T05:34:30Z |
| publishDate | 2018 |
| record_format | dspace |
| spelling | ntu-10356/876642023-02-28T19:23:45Z Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies Kee, J. W. Shao, H. Kee, C. W. Lu, Yunpeng Soo, Han Sen Tan, Choon Hong School of Physical and Mathematical Sciences Photoredox Catalysis C-H Fluorination DRNTU::Science::Chemistry Chemoselective photoredox fluorination is an appealing approach to access fluorinated fine chemicals such as active pharmaceutical ingredients, but most of the known procedures currently lack time-resolved mechanistic insights. We use nanosecond transient absorption spectroscopy and density functional theory (DFT) calculations to elucidate the elementary steps after irradiation in a photocatalytic fluorination procedure that we reported previously. Time-resolved optical spectroscopy suggests that direct reaction only occurs between the photoexcited anthraquinone (AQN) and Selectfluor®. We have observed spectroscopic evidence of a novel transient AQN–Selectfluor® species for the first time. Further studies by DFT calculations suggest that the AQN–Selectfluor® triplet exciplex formed by photoirradiation is responsible for initiating and sustaining the fluorination reaction. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) Accepted version 2018-12-18T03:00:46Z 2019-12-06T16:46:47Z 2018-12-18T03:00:46Z 2019-12-06T16:46:47Z 2017 Journal Article Kee, J. W., Shao, H., Kee, C. W., Lu, Y., Soo, H. S., & Tan, C. H. (2017). Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies. Catalysis Science & Technology, 7(4), 848-857. doi:10.1039/C6CY02484J 2044-4753 https://hdl.handle.net/10356/87664 http://hdl.handle.net/10220/47035 10.1039/C6CY02484J en Catalysis Science & Technology © 2017 Royal Society of Chemistry. This is the author created version of a work that has been peer reviewed and accepted for publication by Catalysis Science & Technology, Royal Society of Chemistry. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1039/C6CY02484J]. 10 p. application/pdf |
| spellingShingle | Photoredox Catalysis C-H Fluorination DRNTU::Science::Chemistry Kee, J. W. Shao, H. Kee, C. W. Lu, Yunpeng Soo, Han Sen Tan, Choon Hong Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies |
| title | Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies |
| title_full | Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies |
| title_fullStr | Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies |
| title_full_unstemmed | Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies |
| title_short | Mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time-resolved and DFT studies |
| title_sort | mechanistic insights for the photoredox organocatalytic fluorination of aliphatic carbons by anthraquinone using time resolved and dft studies |
| topic | Photoredox Catalysis C-H Fluorination DRNTU::Science::Chemistry |
| url | https://hdl.handle.net/10356/87664 http://hdl.handle.net/10220/47035 |
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