Cargando…
Understanding the unique reactivity patterns of nickel/JoSPOphos manifold in the nickel-catalyzed enantioselective C–H cyclization of imidazoles
The 3d transition metal-catalyzed enantioselective C–H functionalization provides a sustainable strategy for the construction of chiral molecules. A better understanding of the catalytic nature of the reactions and the factors controlling the enantioselectivity is important for rational design of mo...
Autores principales: | , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
The Royal Society of Chemistry
2020
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8178989/ https://www.ncbi.nlm.nih.gov/pubmed/34163805 http://dx.doi.org/10.1039/d0sc04578k |
_version_ | 1783703687925858304 |
---|---|
author | Liu, Jian-Biao Wang, Xin Messinis, Antonis M. Liu, Xiao-Jun Kuniyil, Rositha Chen, De-Zhan Ackermann, Lutz |
author_facet | Liu, Jian-Biao Wang, Xin Messinis, Antonis M. Liu, Xiao-Jun Kuniyil, Rositha Chen, De-Zhan Ackermann, Lutz |
author_sort | Liu, Jian-Biao |
collection | PubMed |
description | The 3d transition metal-catalyzed enantioselective C–H functionalization provides a sustainable strategy for the construction of chiral molecules. A better understanding of the catalytic nature of the reactions and the factors controlling the enantioselectivity is important for rational design of more efficient systems. Herein, the mechanisms of Ni-catalyzed enantioselective C–H cyclization of imidazoles are investigated by density functional theory (DFT) calculations. Both the π-allyl nickel(ii)-promoted σ-complex-assisted metathesis (σ-CAM) and the nickel(0)-catalyzed oxidative addition (OA) mechanisms are disfavored. In addition to the typically proposed ligand-to-ligand hydrogen transfer (LLHT) mechanism, the reaction can also proceed via an unconventional σ-CAM mechanism that involves hydrogen transfer from the JoSPOphos ligand to the alkene through P–H oxidative addition/migratory insertion, C(sp(2))–H activation via σ-CAM, and C–C reductive elimination. Importantly, computational results based on this new mechanism can indeed reproduce the experimentally observed enantioselectivities. Further, the catalytic activity of the π-allyl nickel(ii) complex can be rationalized by the regeneration of the active nickel(0) catalyst via a stepwise hydrogen transfer, which was confirmed by experimental studies. The calculations reveal several significant roles of the secondary phosphine oxide (SPO) unit in JoSPOphos during the reaction. The improved mechanistic understanding will enable design of novel enantioselective C–H transformations. |
format | Online Article Text |
id | pubmed-8178989 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | The Royal Society of Chemistry |
record_format | MEDLINE/PubMed |
spelling | pubmed-81789892021-06-22 Understanding the unique reactivity patterns of nickel/JoSPOphos manifold in the nickel-catalyzed enantioselective C–H cyclization of imidazoles Liu, Jian-Biao Wang, Xin Messinis, Antonis M. Liu, Xiao-Jun Kuniyil, Rositha Chen, De-Zhan Ackermann, Lutz Chem Sci Chemistry The 3d transition metal-catalyzed enantioselective C–H functionalization provides a sustainable strategy for the construction of chiral molecules. A better understanding of the catalytic nature of the reactions and the factors controlling the enantioselectivity is important for rational design of more efficient systems. Herein, the mechanisms of Ni-catalyzed enantioselective C–H cyclization of imidazoles are investigated by density functional theory (DFT) calculations. Both the π-allyl nickel(ii)-promoted σ-complex-assisted metathesis (σ-CAM) and the nickel(0)-catalyzed oxidative addition (OA) mechanisms are disfavored. In addition to the typically proposed ligand-to-ligand hydrogen transfer (LLHT) mechanism, the reaction can also proceed via an unconventional σ-CAM mechanism that involves hydrogen transfer from the JoSPOphos ligand to the alkene through P–H oxidative addition/migratory insertion, C(sp(2))–H activation via σ-CAM, and C–C reductive elimination. Importantly, computational results based on this new mechanism can indeed reproduce the experimentally observed enantioselectivities. Further, the catalytic activity of the π-allyl nickel(ii) complex can be rationalized by the regeneration of the active nickel(0) catalyst via a stepwise hydrogen transfer, which was confirmed by experimental studies. The calculations reveal several significant roles of the secondary phosphine oxide (SPO) unit in JoSPOphos during the reaction. The improved mechanistic understanding will enable design of novel enantioselective C–H transformations. The Royal Society of Chemistry 2020-11-04 /pmc/articles/PMC8178989/ /pubmed/34163805 http://dx.doi.org/10.1039/d0sc04578k Text en This journal is © The Royal Society of Chemistry https://creativecommons.org/licenses/by-nc/3.0/ |
spellingShingle | Chemistry Liu, Jian-Biao Wang, Xin Messinis, Antonis M. Liu, Xiao-Jun Kuniyil, Rositha Chen, De-Zhan Ackermann, Lutz Understanding the unique reactivity patterns of nickel/JoSPOphos manifold in the nickel-catalyzed enantioselective C–H cyclization of imidazoles |
title | Understanding the unique reactivity patterns of nickel/JoSPOphos manifold in the nickel-catalyzed enantioselective C–H cyclization of imidazoles |
title_full | Understanding the unique reactivity patterns of nickel/JoSPOphos manifold in the nickel-catalyzed enantioselective C–H cyclization of imidazoles |
title_fullStr | Understanding the unique reactivity patterns of nickel/JoSPOphos manifold in the nickel-catalyzed enantioselective C–H cyclization of imidazoles |
title_full_unstemmed | Understanding the unique reactivity patterns of nickel/JoSPOphos manifold in the nickel-catalyzed enantioselective C–H cyclization of imidazoles |
title_short | Understanding the unique reactivity patterns of nickel/JoSPOphos manifold in the nickel-catalyzed enantioselective C–H cyclization of imidazoles |
title_sort | understanding the unique reactivity patterns of nickel/jospophos manifold in the nickel-catalyzed enantioselective c–h cyclization of imidazoles |
topic | Chemistry |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8178989/ https://www.ncbi.nlm.nih.gov/pubmed/34163805 http://dx.doi.org/10.1039/d0sc04578k |
work_keys_str_mv | AT liujianbiao understandingtheuniquereactivitypatternsofnickeljospophosmanifoldinthenickelcatalyzedenantioselectivechcyclizationofimidazoles AT wangxin understandingtheuniquereactivitypatternsofnickeljospophosmanifoldinthenickelcatalyzedenantioselectivechcyclizationofimidazoles AT messinisantonism understandingtheuniquereactivitypatternsofnickeljospophosmanifoldinthenickelcatalyzedenantioselectivechcyclizationofimidazoles AT liuxiaojun understandingtheuniquereactivitypatternsofnickeljospophosmanifoldinthenickelcatalyzedenantioselectivechcyclizationofimidazoles AT kuniyilrositha understandingtheuniquereactivitypatternsofnickeljospophosmanifoldinthenickelcatalyzedenantioselectivechcyclizationofimidazoles AT chendezhan understandingtheuniquereactivitypatternsofnickeljospophosmanifoldinthenickelcatalyzedenantioselectivechcyclizationofimidazoles AT ackermannlutz understandingtheuniquereactivitypatternsofnickeljospophosmanifoldinthenickelcatalyzedenantioselectivechcyclizationofimidazoles |