Chemical Forums
Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: ambroz on January 31, 2007, 05:33:50 AM
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Hello.
Please, have you any experience with [Au(Me2S)Cl] and/or [Au(PPh3)Cl] complex?
Are they stable? Are they air and water sensitive?
A
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Au(I) is easily oxidised to Au(III) so you have to either have it very well shielded or away from water and air.
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I've worked with the latter compound a lot this summer, it is easily made from H[AuCl4] (obtained from elemental gold dissolved in aqua regia) and PPh3 and can be stored on the shelf. I am quite sure that Me2SAuCl is the least stable of them, though I have no experience of this compuound. The triphenylphospine complex is by far the most stable phospine complex, and ligated with Cl it is more stable than with I etc.
The Me3PAuCl complex crystallizes in in a helicoidal strands, but there exists many different spatial motifs like tetramers, dimers and monomers (in this case Ph3PAuCl and for instance Me3PAuI). This is a results of Au-Au interactions estimated to 30kJ/mol, more or less in the region of hydrogen bonds. Some Au(I) compunds are potent catalysts in organic chemistry at ambient temperatures, sometimes with similar catalytic properties as Au(III) complexes. However acting as a catalyst, the solvatised complex is quite easily driven out as collodial elemental gold (which can appear black, red etc depending on the sizes of the collodial particle).
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Would you happen to have the literature references that would contain those preps?
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Unfortunately no, since they reside in a box on the other side of the globe right now, but you can easily find references and synths by looking up the compounds in the Cambridge structural database and follow some trails.