The reactivity of tetrachloroauric acid (HAuCl 4 ) with readily accessible bidentate N-donor ligands affords N,N-ligated Au(iii) center complexes. These compounds are useful precursors of stable catalysts, anticancer agents, and building blocks for materials. This report provides detailed insight into intermediates, equilibria, the counter anion effect, and structural variability, using spectroscopy, crystallography and computational tools. Novel mixed-valence Au(i) and Au(iii) complexes [Au(o-phen)Cl 2 ] 2 [AuCl 2 ][AuCl 4 ] and [Au(o-phen)Cl 2 ][AuCl 2 ] having AuCl 2 - and AuCl 4 - anions linearly arranged in the axial sites of the square-planar Au(o-phen)Cl 2 cation were discovered. Other competing side products of the reaction studied revealed protonated N,N-bidentate ligands with AuCl 4 - anions. Quantitative variable temperature NMR studies reveal that for a mixture of target Au(iii) salt and the protonated ligand, the reaction favors the irreversible formation of the side product. Using a rapid (30 min) temperature controlled protocol, the desired coordinated species is accessible in respectable yields while avoiding side products.
|Number of pages||7|
|State||Published - 2019|
Bibliographical noteFunding Information:
Financial support was provided by the University of Kentucky (UK). This study made use of the UK NMR facility, the UK X-ray facility with funds from the MRI program (grants CHE-0319176 and CHE-1625732), and Boston University Mass spectrometry facility. We thank Dr. Justin Mobley for assistance with VT-NMR.
© 2019 The Royal Society of Chemistry.
ASJC Scopus subject areas
- Inorganic Chemistry