ISSN:
0009-2940
Keywords:
Gold
;
S ligands
;
Carboxylato complexes
;
Thioether complexes
;
Sulfonium complexes
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Treatment of 2-mercaptoaniline with {[(Ph3P)Au]3O}+ BF-4 leads to a regioselective auration to give the (2-aminophenyl)sulfonium complex {(2-H2NC6H4S[Au(PPh3)]2}+ BF-4 (1) as the sole product. With the same reagent, 4-hydroxyphenyl)sulfonium salt 2, and 2-mercaptopyridine is converted into the 2-pyridylsulfonium salt 3. Dinuclear auration of the thiol functions is thus clearly favoured over the reaction at any of the other functional groups (-NH2, -py, -OH). As shown in earlier work, this is also true for HS-functional carboxylic acids. With an excess of the oxonium reagent, however, 2-mercaptosuccinic acid was now found to be converted into a tetranuclear complex with a doubly aurated sulfonium group and monoaurated carboxylate functions (4). Bis(2-mercaptoethyl) ether and thioether react with the oxonium salt to give tetranuclear bis(sulfonium salts) 5, 6, with bifurcated {-S[Au(PPh3)]2}+ groups at both ends. Structural studies of compounds 1, 5 and 6 showed the cations to be aggregated into centrosymmetrical dimers through short Au-Au contacts. Compound 5 forms one-dimensional infinite chains through a similar aggregation via the two bifurcated sulfonium end groups of each individual dicationic unit. The dications of compound 6 are associated only into centrosymmetrical dimers leaving one of the two sulfonium groups of each unit without auriophilic contacts to neighbouring dications, probably owing to an internal Au-S contact with the thioether function.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19971300515
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