Issue 23, 2014

Facile oxidation of NHC-Au(i) to NHC-Au(iii) complexes by CsBr3

Abstract

CsBr3 was investigated as a new and convenient oxidant for NHC-Au(I) complexes (NHC = imidazo[1,5-a]pyridin-3-ylidene) for the preparation of the respective Au(III) complexes. The Au(I) complexes were synthesized by the silver salt method using [(NHC)2Ag]PF6 and (tht)AuBr. Unexpectedly, the reactions yielded both neutral (NHC)AuBr and ionic [(NHC)2Au]PF6, depending on the N-substituent of the NHC ligand. Oxidation with CsBr3 gave the complexes (NHC)AuBr3 and [(NHC)2AuBr2]PF6 in high yields and purity, which proves the suitability of this reagent. The complexes were further characterised by X-ray diffraction and electronic absorption and emission spectroscopy. The Au(I) complexes exhibit a dual emission attributable to intraligand fluorescence and phosphorescence at both room temperature and 77 K. Upon irradiation with polychromatic light (λ > 305 nm), the Au(III) complexes are cleanly photo-reduced to the Au(I) congener.

Graphical abstract: Facile oxidation of NHC-Au(i) to NHC-Au(iii) complexes by CsBr3

Supplementary files

Article information

Article type
Paper
Submitted
07 Mar 2014
Accepted
16 Apr 2014
First published
17 Apr 2014

Dalton Trans., 2014,43, 8781-8791

Author version available

Facile oxidation of NHC-Au(I) to NHC-Au(III) complexes by CsBr3

M. Kriechbaum, D. Otte, M. List and U. Monkowius, Dalton Trans., 2014, 43, 8781 DOI: 10.1039/C4DT00695J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements