Trifluoromethylation of a Well‐Defined Square‐Planar Aryl‐NiII Complex involving NiIII/CF3. and NiIV−CF3 Intermediate Species
dc.contributor.author
dc.date.accessioned
2018-05-14T12:13:48Z
dc.date.available
2018-05-14T12:13:48Z
dc.date.issued
2017-08-25
dc.identifier.issn
0947-6539
dc.identifier.uri
dc.description.abstract
Ni-mediated trifluoromethylation of an aryl−Br bond in model macrocyclic ligands (L n −Br) has been thoroughly studied, starting with an oxidative addition at Ni 0 to obtain well-defined aryl-Ni II -Br complexes ([L n −Ni II ]Br). Abstraction of the halide with AgX (X=OTf − or ClO 4 − ) thereafter provides [L n −Ni II ](OTf). The nitrate analogue has been obtained through a direct C−H activation of an aryl−H bond using Ni II salts, and this route has been studied by X-ray absorption spectroscopy (XAS). Crystallographic XRD and XAS characterization has shown a tight macrocyclic coordination in the aryl−Ni II complex, which may hamper direct reaction with nucleophiles. On the contrary, enhanced reactivity is observed with oxidants, and the reaction of [L n −Ni II ](OTf) with CF 3 + sources afforded L n −CF 3 products in quantitative yield. A combined experimental and theoretical mechanistic study provides new insights into the operative mechanism for this transformation. Computational analysis indicates the occurrence of an initial single electron transfer (SET) to 5-(trifluoromethyl)dibenzothiophenium triflate (TDTT), producing a transient L 1 −Ni III /CF 3 . adduct, which rapidly recombines to form a [L 1 -Ni IV -CF 3 ](X) 2 intermediate species. A final facile reductive elimination affords L 1 −CF 3 . The well-defined square-planar model system studied here permits to gain fundamental knowledge on the rich redox chemistry of nickel, which is sought to facilitate the development of new Ni-based trifluoromethylation methodologies
dc.description.sponsorship
This work was supported by grants from the European Research Council (Starting Grant Project ERC-2011-StG-277801), the Spanish MICINN (CTQ2016-77989-P and CTQ2014-52525-P), the Catalan DIUE of the Generalitat de Catalunya (2014SGR862 and 2014SGR931).
dc.format.mimetype
application/pdf
dc.language.iso
eng
dc.publisher
Wiley
dc.relation
MINECO/PE 2016-2018/CTQ2016-77989-P
info:eu-repo/grantAgreement/MINECO//CTQ2014-52525-P/ES/FUNCIONALES DFT PARA EL CALCULO DE PROPIEDADES OPTICAS NO LINEALES/
dc.relation.isformatof
Reproducció digital del document publicat a: https://doi.org/10.1002/chem.201702168
dc.relation.ispartof
© Chemistry - A European Journal, 2017, vol. 23, p. 11662-11668
dc.relation.ispartofseries
Articles publicats (D-Q)
dc.rights
Tots els drets reservats
dc.subject
dc.title
Trifluoromethylation of a Well‐Defined Square‐Planar Aryl‐NiII Complex involving NiIII/CF3. and NiIV−CF3 Intermediate Species
dc.type
info:eu-repo/semantics/article
dc.rights.accessRights
info:eu-repo/semantics/embargoedAccess
dc.date.embargoEndDate
info:eu-repo/date/embargoEnd/2026-01-01
dc.relation.projectID
info:eu-repo/grantAgreement/EC/FP7/277801/EU/Sustainable C-X and C-H Functionalization Catalyzed by Copper(III) Species/SUSCATCU3
dc.type.version
info:eu-repo/semantics/publishedVersion
dc.identifier.doi
dc.identifier.idgrec
027310
dc.contributor.funder
dc.type.peerreviewed
peer-reviewed
dc.relation.FundingProgramme
dc.relation.ProjectAcronym
dc.identifier.eissn
1521-3765