Phosphine-gold® complexes synthesis

The number of gold complexes containing tertiary phosphines, arsines, or stibines as ligands is large because of the wide use of the fragment AuL+, mainly with L = PPh3, in the synthesis of... 

Polyauration starts from the carbon atom for which the species with four, five and six gold atoms have been prepared. These are available from the reaction of polyborylmethanes with [AuCl(PR3)] or trimethylsilyl diazomethanes with [0(AuPR3)3]+. The tetranuclear derivatives are formed with bulky phosphines and less sterically demanding phosphines enable the synthesis of the hypervalent species [230]. The structures of these complexes are tetrahedral, trigonal bypiramidal and octahedral, respectively (Figure 1.36). Many complexes of the type [RC(AuPR3)4]+ [231] have also been synthesized. 

Some dissociation of free phosphine is also observed in solution [97]. A relevant finding in this work is that the free phosphine is also active [95] (originally reported in 1966 [110]), and the implication is that the gold complex serves as a releasing mechanism for the cytotoxic ligand. Since copper salts potentiate the activity of free phosphine [111] there is a possibility of in vivo phosphine release followed by copper activation — similar in concept to the possible antitumour mechanisms of 1,10-phenan-throline and the thiosemicarbazones. In pursuit of this line, Cu(II) was shown to displace dppe from [Au(dppe)2]Cl [112] to give a Cu(I) complex. Further synthesis and testing of copper-diphosphine complexes struc-... 

Synthesis and design of novel tetranuclear and dinuclear gold(I) phosphine acetylide complexes. First X-ray crystal structures of a tetranuclear ([Au4(tppb)(C Ph)4]) and a related dinuclear ([AUjfdppb) (C=CPh)2] complex, V. W. W. Yam, S. W. K. Choi, K. K. Cheung, Organometallics 1996,15,1734. 

Synthesis, structure, luminescence, and Raman-determined excited state distortions of a trinuclear gold(I) phosphine thiolate complex, S. D. Hanna, S. I. Khan, J. I. Zink, Inorg. Chem. 1996, 35, 5813. 

Hydroamination of olefins has received considerable attention this year as a route to functionalized piperidines and spiropiperidines, particularly in regard to the investigation of new catalysts. In the synthesis of spiro-piperidines, two new mild and more general intramolecular hydroamination protocols were developed this year. One protocol uses a cationic gold-phosphine complex (Au[P(fBu)2(o-biphenyl)]Cl) as the catalyst... 

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