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Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study
Gold(I)-catalysed direct allylic etherifications have been successfully carried out with chirality transfer to yield enantioenriched, γ-substituted secondary allylic ethers. Our investigations include a full substrate-scope screen to ascertain substituent effects on the regioselectivity, stereoselec...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
WILEY-VCH Verlag
2015
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4586480/ https://www.ncbi.nlm.nih.gov/pubmed/26248980 http://dx.doi.org/10.1002/chem.201501607 |
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author | Barker, Graeme Johnson, David G Young, Paul C Macgregor, Stuart A Lee, Ai-Lan |
author_facet | Barker, Graeme Johnson, David G Young, Paul C Macgregor, Stuart A Lee, Ai-Lan |
author_sort | Barker, Graeme |
collection | PubMed |
description | Gold(I)-catalysed direct allylic etherifications have been successfully carried out with chirality transfer to yield enantioenriched, γ-substituted secondary allylic ethers. Our investigations include a full substrate-scope screen to ascertain substituent effects on the regioselectivity, stereoselectivity and efficiency of chirality transfer, as well as control experiments to elucidate the mechanistic subtleties of the chirality-transfer process. Crucially, addition of molecular sieves was found to be necessary to ensure efficient and general chirality transfer. Computational studies suggest that the efficiency of chirality transfer is linked to the aggregation of the alcohol nucleophile around the reactive π-bound Au–allylic ether complex. With a single alcohol nucleophile, a high degree of chirality transfer is predicted. However, if three alcohols are present, alternative proton transfer chain mechanisms that erode the efficiency of chirality transfer become competitive. |
format | Online Article Text |
id | pubmed-4586480 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | WILEY-VCH Verlag |
record_format | MEDLINE/PubMed |
spelling | pubmed-45864802015-10-05 Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study Barker, Graeme Johnson, David G Young, Paul C Macgregor, Stuart A Lee, Ai-Lan Chemistry Full Papers Gold(I)-catalysed direct allylic etherifications have been successfully carried out with chirality transfer to yield enantioenriched, γ-substituted secondary allylic ethers. Our investigations include a full substrate-scope screen to ascertain substituent effects on the regioselectivity, stereoselectivity and efficiency of chirality transfer, as well as control experiments to elucidate the mechanistic subtleties of the chirality-transfer process. Crucially, addition of molecular sieves was found to be necessary to ensure efficient and general chirality transfer. Computational studies suggest that the efficiency of chirality transfer is linked to the aggregation of the alcohol nucleophile around the reactive π-bound Au–allylic ether complex. With a single alcohol nucleophile, a high degree of chirality transfer is predicted. However, if three alcohols are present, alternative proton transfer chain mechanisms that erode the efficiency of chirality transfer become competitive. WILEY-VCH Verlag 2015-09-21 2015-08-06 /pmc/articles/PMC4586480/ /pubmed/26248980 http://dx.doi.org/10.1002/chem.201501607 Text en © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. https://creativecommons.org/licenses/by/4.0/ © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Full Papers Barker, Graeme Johnson, David G Young, Paul C Macgregor, Stuart A Lee, Ai-Lan Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study |
title | Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study |
title_full | Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study |
title_fullStr | Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study |
title_full_unstemmed | Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study |
title_short | Chirality Transfer in Gold(I)-Catalysed Direct Allylic Etherifications of Unactivated Alcohols: Experimental and Computational Study |
title_sort | chirality transfer in gold(i)-catalysed direct allylic etherifications of unactivated alcohols: experimental and computational study |
topic | Full Papers |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4586480/ https://www.ncbi.nlm.nih.gov/pubmed/26248980 http://dx.doi.org/10.1002/chem.201501607 |
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