Syntheses, crystal structures, reactivity, and photochemistry of gold(III) bromides bearing N-heterocyclic carbenes

Author(s)
Christa Hirtenlehner, Charlotte Krims, Johanna Hölbling, Manuela List, Manfred Zabel, Michel Fleck, Raphael J. F. Berger, Wolfgang Schoefberger, Uwe Monkowius
Abstract

Gold(I) complexes bearing N-heterocyclic carbenes (NHC) of the type (NHC)AuBr (3a/3b) [NHC = 1-methyl-3-benzylimidazol-2-ylidene (= MeBnIm), and 1,3-dibenzylimidazol-2-ylidene (= Bn2Im)] are prepared by transmetallation reactions of (tht)AuBr (tht = tetrahydrothiophene) and (NHC)AgBr (2a/2b). The homoleptic, ionic complexes [(NHC)2Au]Br (6a/6b) are synthesized by the reaction with free carbene. Successive oxidation of 3a/3b and 6a/6b with bromine gave the respective (NHC)AuBr3 (4a/4b) and [(NHC)2AuBr2]Br (7a/7b) in good overall yields as yellow powders. All complexes were characterized by NMR spectroscopy, mass spectrometry, elemental analysis and single crystal X-ray diffraction. Reactions of the Au(III) complexes towards anionic ligands like carboxylates, phenolates and thiophenolates were investigated and result in a complete or partial reduction to a Au(I) complex. Irradiation of the Au(III) complexes with UV light yield the Au(I) congeners in a clean photo-reaction.

Organisation(s)
Department of Mineralogy and Crystallography
External organisation(s)
Johannes Kepler Universität Linz, University Hospital Regensburg, Paris-Lodron Universität Salzburg
Journal
Dalton Transactions
Volume
40
Pages
9899-9910
No. of pages
12
ISSN
1477-9226
Publication date
2011
Peer reviewed
Yes
Austrian Fields of Science 2012
105113 Crystallography
Portal url
https://ucrisportal.univie.ac.at/en/publications/bef93b84-4ba6-4db4-92d1-c8432ad0c727