Thiolato-gold complexes

Soluble RSAu oligomers have been observed to form bis(thiolato) gold(I) complexes in the presence of thiols [11, 29-33] ... 

However, [CySAujn is found to redissolve when a large excess of CySH is present. This is due to the formation of the bis(cysteinato)gold(I) complex, [Au(SCy)2], which at pH 7.4 is favored. This is an example of bis(thiolato)gold(I) formation. 

These bis(thiolato)gold(I) complexes are useful models for providing insights into the chemistry of the end products of the reactions between 1 1 gold thiolates and any excess (including other) thiol, including some reactions with proteins in vivo. 

No structure determinations on simple bis(thiolato)gold(I) complexes have yet been reported, but they are assumed to have linear stereochemistry as in [Au(S203)2]3 and in the complex D-penicillamine derivative Na[Au2Ni2(pen)4], of structure (21)., 269 270... 

M ) are not as high as might be expected, and the reaction is readily reversed to the left at acid pH values. Neither tris- nor tetra-kis-thiolato gold(I) complexes have been characterized, in contrast to the isoelectronic Hg(II). It is notable that the compartments of cells that accumulate much gold (lysosomes) can be quite acidic (pH 5) and that bisthiolato gold(I) complexes readily revert to 1 1 polymers at low... 

Apart from gold(I) phosphine systems, gold(I) chalcogenido and thiolato complexes represent another fast growing area of research in luminescent gold complexes. One of the reasons for such... 

Chahda, R.K., Kumar, R. and Tuck, D.G. (1987) The direct electrochemical synthesis of thiolato complexes of copper, silver, and gold molecular structure of [Cu(SC H4CH3-o) (l,10-phenanthroline)]2.CH3CN , Can. J. Chem., 65, 1336-1342. 

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