Cargando…
Ultrafast photoactivation of C─H bonds inside water-soluble nanocages
Light energy absorbed by molecules can be harnessed to activate chemical bonds with extraordinary speed. However, excitation energy redistribution within various molecular degrees of freedom prohibits bond-selective chemistry. Inspired by enzymes, we devised a new photocatalytic scheme that preorgan...
Autores principales: | , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Association for the Advancement of Science
2019
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6386559/ https://www.ncbi.nlm.nih.gov/pubmed/30801018 http://dx.doi.org/10.1126/sciadv.aav4806 |
_version_ | 1783397400308613120 |
---|---|
author | Das, Ankita Mandal, Imon Venkatramani, Ravindra Dasgupta, Jyotishman |
author_facet | Das, Ankita Mandal, Imon Venkatramani, Ravindra Dasgupta, Jyotishman |
author_sort | Das, Ankita |
collection | PubMed |
description | Light energy absorbed by molecules can be harnessed to activate chemical bonds with extraordinary speed. However, excitation energy redistribution within various molecular degrees of freedom prohibits bond-selective chemistry. Inspired by enzymes, we devised a new photocatalytic scheme that preorganizes and polarizes target chemical bonds inside water-soluble cationic nanocavities to engineer selective functionalization. Specifically, we present a route to photoactivate weakly polarized sp(3) C─H bonds in water via host-guest charge transfer and control its reactivity with aerial O(2). Electron-rich aromatic hydrocarbons self-organize inside redox complementary supramolecular cavities to form photoactivatable host-guest charge transfer complexes in water. An ultrafast C─H bond cleavage within ~10 to 400 ps is triggered by visible-light excitation, through a cage-assisted and solvent water–assisted proton-coupled electron transfer reaction. The confinement prolongs the lifetime of the carbon-centered radical to enable a facile yet selective reaction with molecular O(2) leading to photocatalytic turnover of oxidized products in water. |
format | Online Article Text |
id | pubmed-6386559 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | American Association for the Advancement of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-63865592019-02-23 Ultrafast photoactivation of C─H bonds inside water-soluble nanocages Das, Ankita Mandal, Imon Venkatramani, Ravindra Dasgupta, Jyotishman Sci Adv Research Articles Light energy absorbed by molecules can be harnessed to activate chemical bonds with extraordinary speed. However, excitation energy redistribution within various molecular degrees of freedom prohibits bond-selective chemistry. Inspired by enzymes, we devised a new photocatalytic scheme that preorganizes and polarizes target chemical bonds inside water-soluble cationic nanocavities to engineer selective functionalization. Specifically, we present a route to photoactivate weakly polarized sp(3) C─H bonds in water via host-guest charge transfer and control its reactivity with aerial O(2). Electron-rich aromatic hydrocarbons self-organize inside redox complementary supramolecular cavities to form photoactivatable host-guest charge transfer complexes in water. An ultrafast C─H bond cleavage within ~10 to 400 ps is triggered by visible-light excitation, through a cage-assisted and solvent water–assisted proton-coupled electron transfer reaction. The confinement prolongs the lifetime of the carbon-centered radical to enable a facile yet selective reaction with molecular O(2) leading to photocatalytic turnover of oxidized products in water. American Association for the Advancement of Science 2019-02-22 /pmc/articles/PMC6386559/ /pubmed/30801018 http://dx.doi.org/10.1126/sciadv.aav4806 Text en Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). http://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license (http://creativecommons.org/licenses/by-nc/4.0/) , which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited. |
spellingShingle | Research Articles Das, Ankita Mandal, Imon Venkatramani, Ravindra Dasgupta, Jyotishman Ultrafast photoactivation of C─H bonds inside water-soluble nanocages |
title | Ultrafast photoactivation of C─H bonds inside water-soluble nanocages |
title_full | Ultrafast photoactivation of C─H bonds inside water-soluble nanocages |
title_fullStr | Ultrafast photoactivation of C─H bonds inside water-soluble nanocages |
title_full_unstemmed | Ultrafast photoactivation of C─H bonds inside water-soluble nanocages |
title_short | Ultrafast photoactivation of C─H bonds inside water-soluble nanocages |
title_sort | ultrafast photoactivation of c─h bonds inside water-soluble nanocages |
topic | Research Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6386559/ https://www.ncbi.nlm.nih.gov/pubmed/30801018 http://dx.doi.org/10.1126/sciadv.aav4806 |
work_keys_str_mv | AT dasankita ultrafastphotoactivationofchbondsinsidewatersolublenanocages AT mandalimon ultrafastphotoactivationofchbondsinsidewatersolublenanocages AT venkatramaniravindra ultrafastphotoactivationofchbondsinsidewatersolublenanocages AT dasguptajyotishman ultrafastphotoactivationofchbondsinsidewatersolublenanocages |