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Z. Naturforsch. 2013,
68b, 467 – 473
doi:10.5560/ZNB.2013-3076
Ligand Exchange at a Gold(I) Carbene Complex
Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 30, D-48149 Münster, Germany
Reprint requests to Prof. Dr. F. E. Hahn. Fax: +49 251 8333108. E-mail:
fehahn@uni-muenster.de
Received February 28, 2013 / published online Juli 2, 2013
Dedicated to Professor Heinrich Nöth on the occasion of his 85th birthday
Gold complex [AuCl(NHC)] (NHC = N,N′-dipropylbenzimidazolin-2-ylidene) 1 undergoes facile substitution reactions at the gold(I) center. Treatment of 1 with anionic phenylacetylide or thiophenolate led to the neutral gold complexes 2 and 3, respectively. The cationic gold complexes [Au(NHC)(pyridine)](BF4) [4]BF4 and [Au2(NHC)2(4,4′-bipyridine)](BF4)2 [5](BF4)2 were obtained via abstraction of the chloro ligand from 1 and reaction with the appropriate amine. Reaction of 1 with AgBF4 in the presence of PPh3 instead of an amine led to an inseparable product mixture of the mixed NHC/PPh3 complex [6]BF4, the dicarbene complex [Au(NHC)2]BF4, [7]BF4, and [Au(PPh3)2]BF4, [8]BF4. Crystals of 2 and [6]BF4 were obtained, and X-ray diffraction structure analyses revealed that the gold(I) atoms are coordinated in a linear fashion by the NHC and the co-ligand.
Key words: N-Heterocyclic Carbene, Phosphine, Acetylide Ligand, Gold Complexes