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Evidence for Triplet Sensitization in the Visible‐Light‐Induced [2+2] Photocycloaddition of Eniminium Ions
Εniminium ions were prepared from the corresponding α,β‐unsaturated carbonyl compounds (enones and enals), and were found to be promoted to their respective triplet states by energy transfer. The photoexcited intermediates underwent intra‐ or intermolecular [2+2] photocycloaddition in good yields (5...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
John Wiley and Sons Inc.
2017
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5768022/ https://www.ncbi.nlm.nih.gov/pubmed/29178574 http://dx.doi.org/10.1002/anie.201710441 |
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author | Hörmann, Fabian M. Chung, Tim S. Rodriguez, Elsa Jakob, Matthias Bach, Thorsten |
author_facet | Hörmann, Fabian M. Chung, Tim S. Rodriguez, Elsa Jakob, Matthias Bach, Thorsten |
author_sort | Hörmann, Fabian M. |
collection | PubMed |
description | Εniminium ions were prepared from the corresponding α,β‐unsaturated carbonyl compounds (enones and enals), and were found to be promoted to their respective triplet states by energy transfer. The photoexcited intermediates underwent intra‐ or intermolecular [2+2] photocycloaddition in good yields (50–78 %) upon irradiation at λ=433 nm or λ=457 nm. Iridium or ruthenium complexes with a sufficiently high triplet energy were identified as efficient catalysts (2.5 mol % catalyst loading) for the reaction. The intermolecular [2+2] photocycloaddition of an eniminium ion derived from a chiral secondary amine proceeded with high enantioselectivity (88 % ee). |
format | Online Article Text |
id | pubmed-5768022 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2017 |
publisher | John Wiley and Sons Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-57680222018-02-01 Evidence for Triplet Sensitization in the Visible‐Light‐Induced [2+2] Photocycloaddition of Eniminium Ions Hörmann, Fabian M. Chung, Tim S. Rodriguez, Elsa Jakob, Matthias Bach, Thorsten Angew Chem Int Ed Engl Communications Εniminium ions were prepared from the corresponding α,β‐unsaturated carbonyl compounds (enones and enals), and were found to be promoted to their respective triplet states by energy transfer. The photoexcited intermediates underwent intra‐ or intermolecular [2+2] photocycloaddition in good yields (50–78 %) upon irradiation at λ=433 nm or λ=457 nm. Iridium or ruthenium complexes with a sufficiently high triplet energy were identified as efficient catalysts (2.5 mol % catalyst loading) for the reaction. The intermolecular [2+2] photocycloaddition of an eniminium ion derived from a chiral secondary amine proceeded with high enantioselectivity (88 % ee). John Wiley and Sons Inc. 2017-12-13 2018-01-15 /pmc/articles/PMC5768022/ /pubmed/29178574 http://dx.doi.org/10.1002/anie.201710441 Text en © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial (http://creativecommons.org/licenses/by-nc/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. |
spellingShingle | Communications Hörmann, Fabian M. Chung, Tim S. Rodriguez, Elsa Jakob, Matthias Bach, Thorsten Evidence for Triplet Sensitization in the Visible‐Light‐Induced [2+2] Photocycloaddition of Eniminium Ions |
title | Evidence for Triplet Sensitization in the Visible‐Light‐Induced [2+2] Photocycloaddition of Eniminium Ions |
title_full | Evidence for Triplet Sensitization in the Visible‐Light‐Induced [2+2] Photocycloaddition of Eniminium Ions |
title_fullStr | Evidence for Triplet Sensitization in the Visible‐Light‐Induced [2+2] Photocycloaddition of Eniminium Ions |
title_full_unstemmed | Evidence for Triplet Sensitization in the Visible‐Light‐Induced [2+2] Photocycloaddition of Eniminium Ions |
title_short | Evidence for Triplet Sensitization in the Visible‐Light‐Induced [2+2] Photocycloaddition of Eniminium Ions |
title_sort | evidence for triplet sensitization in the visible‐light‐induced [2+2] photocycloaddition of eniminium ions |
topic | Communications |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5768022/ https://www.ncbi.nlm.nih.gov/pubmed/29178574 http://dx.doi.org/10.1002/anie.201710441 |
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