Gold phosphine complexes, reactions with

Model reactions on [AuCl(PEt3)] with GSH show chloride displacement but no phosphine displacement [40], and intracellular GSH binding to auranofin was also observed by NMR studies on red cells [14]. The presence of the phosphine, necessary for oral administration, may also dictate some of the biochemical differences between auranofin and the injectable gold complexes. The breakdown of auranofin eventually produces Et PO, a reaction interestingly mimicked by 2,3-dimercaptopropanol (or British Anti-Lewisite) in its reactions with gold—phosphine complexes [14]. The phosphine oxide has recently been detected in human serum [41], supporting the theory that, upon cellular distribution, loss of phosphine results in behavior similar to that of non-phosphine containing complexes. 

The intermolecular reaction of alkynes 11-16 with alkenes II-17 catalyzed by gold(I) leads to cyclobutenes II-18 with complete regio- and diastCTeoselectivity. Moderate to good yields are obtained when gold(I) complex 7 with a very bulky phosphine ligand is used (Scheme 3.10) [Ref. 192 in Chap. 1]. This transformation shows that [2-1-2] cycloaddition predominates in the reaction between alkynes and alkenes when the constraints imposed by the tethers are absent, like in the intermolecular process. 

Very few examples of bridging non-cyclic methanides of gold are known. Among them the complex 79 has been reported as the result of the reaction of phosphine-phosphonium derivatives with acetylacetonate derivatives of gold(I) [103,104]. The complexes 80 [89,98], already seen in previous paragraphs, cor-... 

The reaction of the gold(I) complex [Au(C6F5)(tht)j with the water soluble phosphine l,3,5-triaza-7-phosphaadamantane (PTA) gives the complex Au(C6F5) PTA] [28]. 

Tetragoldmethane complexes are obtained from tetra-(boryl)methane compounds upon reaction with gold-halide complexes in the presence of an ionic fluoride (equation 35)." Tetragoldmethane species, such as (1), can only be isolated with bulky tertiary phosphines, L, which shield the molecule from further attack by [TAu]+ nucleophiles. With smaller ligands T, penta- and hexaauration occurs, leading to hypercoordinate carbon compounds. " " " ... 

The reaction of organolithiums or organomagnesium halide reagents with gold halides proceeds similarly to the copper halides in a 1 1 ratio. Their phosphine complexes can be isolated and characterized. In a 2 1 ratio, the transmetallation reaction is followed by ate complexation to form organoaurate complexes ... 

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