Cargando…
Two Directing Groups Used for Metal Catalysed Meta‐C−H Functionalisation Only Effect Ortho Electrophilic C−H Borylation
Two templates used in meta‐directed C−H functionalisation under metal catalysis do not direct meta‐C−H borylation under electrophilic borylation conditions. Using BCl(3) only Lewis adduct formation with Lewis basic sites in the template is observed. While combining BBr(3) and the template containing...
Autores principales: | , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
John Wiley and Sons Inc.
2022
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9828458/ https://www.ncbi.nlm.nih.gov/pubmed/36636663 http://dx.doi.org/10.1002/ejoc.202200901 |
_version_ | 1784867278063403008 |
---|---|
author | Iqbal, Saqib A. Millet, Clement R. P. Pahl, Jürgen Yuan, Kang Ingleson, Michael J. |
author_facet | Iqbal, Saqib A. Millet, Clement R. P. Pahl, Jürgen Yuan, Kang Ingleson, Michael J. |
author_sort | Iqbal, Saqib A. |
collection | PubMed |
description | Two templates used in meta‐directed C−H functionalisation under metal catalysis do not direct meta‐C−H borylation under electrophilic borylation conditions. Using BCl(3) only Lewis adduct formation with Lewis basic sites in the template is observed. While combining BBr(3) and the template containing an amide linker only led to amide directed ortho C−H borylation, with no pyridyl directed meta borylation. The amide directed borylation is selective for the ortho borylation of the aniline derived unit in the template, with no ortho borylation of the phenylacetyl ring – which would also form a six membered boracycle – observed. In the absence of other aromatics amide directed ortho borylation on to phenylacetyl rings can be achieved. The absence of meta‐borylation using two templates indicates a higher barrier to pyridyl directed meta borylation relative to amide directed ortho borylation and suggests that bespoke templates for enabling meta‐directed electrophilic borylation may be required. |
format | Online Article Text |
id | pubmed-9828458 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | John Wiley and Sons Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-98284582023-01-10 Two Directing Groups Used for Metal Catalysed Meta‐C−H Functionalisation Only Effect Ortho Electrophilic C−H Borylation Iqbal, Saqib A. Millet, Clement R. P. Pahl, Jürgen Yuan, Kang Ingleson, Michael J. European J Org Chem Research Articles Two templates used in meta‐directed C−H functionalisation under metal catalysis do not direct meta‐C−H borylation under electrophilic borylation conditions. Using BCl(3) only Lewis adduct formation with Lewis basic sites in the template is observed. While combining BBr(3) and the template containing an amide linker only led to amide directed ortho C−H borylation, with no pyridyl directed meta borylation. The amide directed borylation is selective for the ortho borylation of the aniline derived unit in the template, with no ortho borylation of the phenylacetyl ring – which would also form a six membered boracycle – observed. In the absence of other aromatics amide directed ortho borylation on to phenylacetyl rings can be achieved. The absence of meta‐borylation using two templates indicates a higher barrier to pyridyl directed meta borylation relative to amide directed ortho borylation and suggests that bespoke templates for enabling meta‐directed electrophilic borylation may be required. John Wiley and Sons Inc. 2022-11-25 2022-11-25 /pmc/articles/PMC9828458/ /pubmed/36636663 http://dx.doi.org/10.1002/ejoc.202200901 Text en © 2022 The Authors. European Journal of Organic Chemistry published by Wiley-VCH GmbH https://creativecommons.org/licenses/by/4.0/This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Research Articles Iqbal, Saqib A. Millet, Clement R. P. Pahl, Jürgen Yuan, Kang Ingleson, Michael J. Two Directing Groups Used for Metal Catalysed Meta‐C−H Functionalisation Only Effect Ortho Electrophilic C−H Borylation |
title | Two Directing Groups Used for Metal Catalysed Meta‐C−H Functionalisation Only Effect Ortho Electrophilic C−H Borylation |
title_full | Two Directing Groups Used for Metal Catalysed Meta‐C−H Functionalisation Only Effect Ortho Electrophilic C−H Borylation |
title_fullStr | Two Directing Groups Used for Metal Catalysed Meta‐C−H Functionalisation Only Effect Ortho Electrophilic C−H Borylation |
title_full_unstemmed | Two Directing Groups Used for Metal Catalysed Meta‐C−H Functionalisation Only Effect Ortho Electrophilic C−H Borylation |
title_short | Two Directing Groups Used for Metal Catalysed Meta‐C−H Functionalisation Only Effect Ortho Electrophilic C−H Borylation |
title_sort | two directing groups used for metal catalysed meta‐c−h functionalisation only effect ortho electrophilic c−h borylation |
topic | Research Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9828458/ https://www.ncbi.nlm.nih.gov/pubmed/36636663 http://dx.doi.org/10.1002/ejoc.202200901 |
work_keys_str_mv | AT iqbalsaqiba twodirectinggroupsusedformetalcatalysedmetachfunctionalisationonlyeffectorthoelectrophilicchborylation AT milletclementrp twodirectinggroupsusedformetalcatalysedmetachfunctionalisationonlyeffectorthoelectrophilicchborylation AT pahljurgen twodirectinggroupsusedformetalcatalysedmetachfunctionalisationonlyeffectorthoelectrophilicchborylation AT yuankang twodirectinggroupsusedformetalcatalysedmetachfunctionalisationonlyeffectorthoelectrophilicchborylation AT inglesonmichaelj twodirectinggroupsusedformetalcatalysedmetachfunctionalisationonlyeffectorthoelectrophilicchborylation |