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Boron Carboxylate Catalysis of Homoallylboration
[Image: see text] Boron tris(trifluoroacetate) is identified as the first effective catalyst for the homoallyl- and homocrotylboration of aldehydes by cyclopropylcarbinylboronates. NMR spectroscopic studies and theoretical calculations of key intermediates and transition states both suggest that a l...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Chemical
Society
2014
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4033657/ https://www.ncbi.nlm.nih.gov/pubmed/24754566 http://dx.doi.org/10.1021/jo500599h |
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author | Dugas, Gabrielle J. Lam, Yu-hong Houk, K. N. Krauss, Isaac J. |
author_facet | Dugas, Gabrielle J. Lam, Yu-hong Houk, K. N. Krauss, Isaac J. |
author_sort | Dugas, Gabrielle J. |
collection | PubMed |
description | [Image: see text] Boron tris(trifluoroacetate) is identified as the first effective catalyst for the homoallyl- and homocrotylboration of aldehydes by cyclopropylcarbinylboronates. NMR spectroscopic studies and theoretical calculations of key intermediates and transition states both suggest that a ligand-exchange mechanism, akin to our previously reported PhBCl(2)-promoted homoallylations, is operative. Our experimental and theoretical results also suggest that the catalytic activity of boron tris(trifluoroacetate) might originate from more facile catalytic turnover of the trifluoroacetate ligands (in agreement with DFT calculations) or from a lower propensity for formation of off-pathway reservoir intermediates (as observed by (1)H NMR). This work shows that carboxylates are viable catalytic ligands for homoallyl- and homocrotylations of carbonyl compounds and opens the door to the development of catalytic asymmetric versions of this transformation. |
format | Online Article Text |
id | pubmed-4033657 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2014 |
publisher | American Chemical
Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-40336572015-04-23 Boron Carboxylate Catalysis of Homoallylboration Dugas, Gabrielle J. Lam, Yu-hong Houk, K. N. Krauss, Isaac J. J Org Chem [Image: see text] Boron tris(trifluoroacetate) is identified as the first effective catalyst for the homoallyl- and homocrotylboration of aldehydes by cyclopropylcarbinylboronates. NMR spectroscopic studies and theoretical calculations of key intermediates and transition states both suggest that a ligand-exchange mechanism, akin to our previously reported PhBCl(2)-promoted homoallylations, is operative. Our experimental and theoretical results also suggest that the catalytic activity of boron tris(trifluoroacetate) might originate from more facile catalytic turnover of the trifluoroacetate ligands (in agreement with DFT calculations) or from a lower propensity for formation of off-pathway reservoir intermediates (as observed by (1)H NMR). This work shows that carboxylates are viable catalytic ligands for homoallyl- and homocrotylations of carbonyl compounds and opens the door to the development of catalytic asymmetric versions of this transformation. American Chemical Society 2014-04-23 2014-05-16 /pmc/articles/PMC4033657/ /pubmed/24754566 http://dx.doi.org/10.1021/jo500599h Text en Copyright © 2014 American Chemical Society |
spellingShingle | Dugas, Gabrielle J. Lam, Yu-hong Houk, K. N. Krauss, Isaac J. Boron Carboxylate Catalysis of Homoallylboration |
title | Boron Carboxylate Catalysis
of Homoallylboration |
title_full | Boron Carboxylate Catalysis
of Homoallylboration |
title_fullStr | Boron Carboxylate Catalysis
of Homoallylboration |
title_full_unstemmed | Boron Carboxylate Catalysis
of Homoallylboration |
title_short | Boron Carboxylate Catalysis
of Homoallylboration |
title_sort | boron carboxylate catalysis
of homoallylboration |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4033657/ https://www.ncbi.nlm.nih.gov/pubmed/24754566 http://dx.doi.org/10.1021/jo500599h |
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