Please use this identifier to cite or link to this item: http://hdl.handle.net/10553/69293
Title: Quantifying electronic similarities between NHC-gold(i) complexes and their isolobal imidazolium precursors
Authors: Azofra Mesa, Luis Miguel 
Veenboer, Richard M. P.
Falivene, Laura
Vummaleti, Sai V. C.
Poater, Albert
Nolan, Steven P.
Cavallo, Luigi
UNESCO Clasification: 3303 ingeniería y tecnología químicas
Keywords: N-Heterocyclic-Carbene
Density-Functional Theory
Integration Scheme
Nmr-Spectroscopy
Chemical-Shifts, et al
Issue Date: 2019
Journal: Physical Chemistry Chemical Physics 
Abstract: A series of NHC-gold(i) (NHC = N-heterocyclic carbene) complexes has been studied by DFT calculations, enabling comparison of electronic and NMR behaviour with related protonated and free NHC molecules. Based on calculations, the NMR resonances of the carbenic C-2 carbon atom in [Au(NHC)(Cl)] and [NHC(H)][Cl] exhibit increased shielding when compared to the free N-heterocyclic carbenes by an average of 46.6 +/- 2.2 and 73.7 +/- 4.3 ppm, respectively. A similar trend is observed when analysing the paramagnetic term of the magnetic shielding tensor. Although gold(i) and proton are considered isolobal fragments, imidazolium compounds lack pi-backdonation due to the energetic unavailability of d-orbitals in H+. We propose that NHC-gold(i) complexes exhibit important pi-backdonation irrespective of the relative amount of sigma-donation between the NHC and gold(i)-X (X = anionic ligand) moieties in Au-NHC complexes. Interestingly, a correlation exists between the calculated shielding for gold (Au-197) and the pi-donation and pi-backdonation contributions. We describe that this correlation also exists when analysing the sigma-backdonation term, a property generally ignored yet representing a significant energetic contribution to the stability of the C-2-Au bond.
URI: http://hdl.handle.net/10553/69293
ISSN: 1463-9076
DOI: 10.1039/c9cp02844g
Source: Physical Chemistry Chemical Physics[ISSN 1463-9076],v. 21 (28), p. 15615-15622
Appears in Collections:Artículos
Thumbnail
Adobe PDF (3,82 MB)
Show full item record

SCOPUSTM   
Citations

5
checked on May 9, 2021

WEB OF SCIENCETM
Citations

5
checked on May 9, 2021

Page view(s)

47
checked on May 10, 2021

Download(s)

26
checked on May 10, 2021

Google ScholarTM

Check

Altmetric


Share



Export metadata



Items in accedaCRIS are protected by copyright, with all rights reserved, unless otherwise indicated.