Cargando…

A DFT-based mechanistic proposal for the light-driven insertion of dioxygen into Pt(ii)–C bonds

The photocatalyzed insertion of dioxygen into the Pt(ii)–methyl bond in terpyridine platinum complexes has been shown to proceed efficiently, but its mechanism remains a challenge. In particular, there are serious counter-intuitive differences in the reactivity of structurally similar complexes. M06...

Descripción completa

Detalles Bibliográficos
Autores principales: Fernández-Alvarez, Victor M., Ho, Sarah K. Y., Britovsek, George J. P., Maseras, Feliu
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Royal Society of Chemistry 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5994795/
https://www.ncbi.nlm.nih.gov/pubmed/29938033
http://dx.doi.org/10.1039/c8sc01161c
_version_ 1783330506010525696
author Fernández-Alvarez, Victor M.
Ho, Sarah K. Y.
Britovsek, George J. P.
Maseras, Feliu
author_facet Fernández-Alvarez, Victor M.
Ho, Sarah K. Y.
Britovsek, George J. P.
Maseras, Feliu
author_sort Fernández-Alvarez, Victor M.
collection PubMed
description The photocatalyzed insertion of dioxygen into the Pt(ii)–methyl bond in terpyridine platinum complexes has been shown to proceed efficiently, but its mechanism remains a challenge. In particular, there are serious counter-intuitive differences in the reactivity of structurally similar complexes. M06 calculations in solvent with a valence double-ζ basis set supplemented by polarization and diffusion shells (benchmarked against ωB97x-D calculations with a larger basis set) are able to provide a satisfactory mechanistic answer. The proposed mechanism starts with the absorption of a photon by the metal complex, which then evolves into a triplet state that reacts with the triplet dioxygen fragment. A variety of possible reaction paths have been identified, some leading to the methylperoxo product and others reverting to the reactants, and the validity of some of these paths has been confirmed by additional experiments. The balance between the barriers towards productive and unproductive paths reproduces the diverging experimental behavior of similar complexes and provides a general mechanistic picture for these processes.
format Online
Article
Text
id pubmed-5994795
institution National Center for Biotechnology Information
language English
publishDate 2018
publisher Royal Society of Chemistry
record_format MEDLINE/PubMed
spelling pubmed-59947952018-06-22 A DFT-based mechanistic proposal for the light-driven insertion of dioxygen into Pt(ii)–C bonds Fernández-Alvarez, Victor M. Ho, Sarah K. Y. Britovsek, George J. P. Maseras, Feliu Chem Sci Chemistry The photocatalyzed insertion of dioxygen into the Pt(ii)–methyl bond in terpyridine platinum complexes has been shown to proceed efficiently, but its mechanism remains a challenge. In particular, there are serious counter-intuitive differences in the reactivity of structurally similar complexes. M06 calculations in solvent with a valence double-ζ basis set supplemented by polarization and diffusion shells (benchmarked against ωB97x-D calculations with a larger basis set) are able to provide a satisfactory mechanistic answer. The proposed mechanism starts with the absorption of a photon by the metal complex, which then evolves into a triplet state that reacts with the triplet dioxygen fragment. A variety of possible reaction paths have been identified, some leading to the methylperoxo product and others reverting to the reactants, and the validity of some of these paths has been confirmed by additional experiments. The balance between the barriers towards productive and unproductive paths reproduces the diverging experimental behavior of similar complexes and provides a general mechanistic picture for these processes. Royal Society of Chemistry 2018-05-04 /pmc/articles/PMC5994795/ /pubmed/29938033 http://dx.doi.org/10.1039/c8sc01161c Text en This journal is © The Royal Society of Chemistry 2018 https://creativecommons.org/licenses/by-nc/3.0/This article is freely available. This article is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported Licence (CC BY-NC 3.0)
spellingShingle Chemistry
Fernández-Alvarez, Victor M.
Ho, Sarah K. Y.
Britovsek, George J. P.
Maseras, Feliu
A DFT-based mechanistic proposal for the light-driven insertion of dioxygen into Pt(ii)–C bonds
title A DFT-based mechanistic proposal for the light-driven insertion of dioxygen into Pt(ii)–C bonds
title_full A DFT-based mechanistic proposal for the light-driven insertion of dioxygen into Pt(ii)–C bonds
title_fullStr A DFT-based mechanistic proposal for the light-driven insertion of dioxygen into Pt(ii)–C bonds
title_full_unstemmed A DFT-based mechanistic proposal for the light-driven insertion of dioxygen into Pt(ii)–C bonds
title_short A DFT-based mechanistic proposal for the light-driven insertion of dioxygen into Pt(ii)–C bonds
title_sort dft-based mechanistic proposal for the light-driven insertion of dioxygen into pt(ii)–c bonds
topic Chemistry
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5994795/
https://www.ncbi.nlm.nih.gov/pubmed/29938033
http://dx.doi.org/10.1039/c8sc01161c
work_keys_str_mv AT fernandezalvarezvictorm adftbasedmechanisticproposalforthelightdriveninsertionofdioxygenintoptiicbonds
AT hosarahky adftbasedmechanisticproposalforthelightdriveninsertionofdioxygenintoptiicbonds
AT britovsekgeorgejp adftbasedmechanisticproposalforthelightdriveninsertionofdioxygenintoptiicbonds
AT maserasfeliu adftbasedmechanisticproposalforthelightdriveninsertionofdioxygenintoptiicbonds
AT fernandezalvarezvictorm dftbasedmechanisticproposalforthelightdriveninsertionofdioxygenintoptiicbonds
AT hosarahky dftbasedmechanisticproposalforthelightdriveninsertionofdioxygenintoptiicbonds
AT britovsekgeorgejp dftbasedmechanisticproposalforthelightdriveninsertionofdioxygenintoptiicbonds
AT maserasfeliu dftbasedmechanisticproposalforthelightdriveninsertionofdioxygenintoptiicbonds