Gold complexes dithiophosphinates

The behavior of Hg(CN)2 toward the dinuclear gold(I) amidinate complexes requires comment. In the case of the dinuclear gold(I) ylide, oxidation of the Au(I) to Au(II) resulted in the formation of a reduced mercury(O) product. Figure 1.19(a) [36]. In the mercury(II) cyanide reaction with the dinuclear gold(I) dithiophosphinate. Figure 1.19(b), the stability of the gold(I)-carbon bond compared... 

Figure 1.19 Schematic representation of the reactions between Hg(CN)2 and the (a) dinuclear gold(l) ylide with loss of Hg(0), (b) dinuclear gold(l) dithiophosphinate with los of AuCN, and with (c) dinuclear Au(l) 2,6-Me2formamidinate complexes.

Another important class of bidentate ligands in gold chemistry are those composed of sulfur donor ligands such as dithiocarbamates, dithiolates, dithiocarboxylates, dithiophosphinates, dithiophosphates, and so on. The complexes prepared with these ligands are generally of the type Au2(p.-SS)(PR3)2]"+ or Au2(p-SS)(p-PP)] [153-155], [Au2(p-SS)2f [156, 157] or Au3( i-SS)2(PPh3)2 [158]. All these... 

Crystal structures of [Au2(E E)2]2+ (E = chalcogen donor atom) have been described with dithiocarbamate [265-271], xantate [272], MNT [273-275], dithiopho-sphonate [276], dithiophosphinate [277], dithiophosphate [278, 279] or trithiocarbo-nate [280] ligands. The gold-gold interaction in complexes shown in Figure 2.48 has been analyzed by ab initio Hartree-Fock calculations [281]. 

Some complexes with particularly interesting structures are formed from gold(I) and N, iV-dialkyldithiocarbamates and 0,0 -diisopropyldithiophosphate,277 279 and probably also for dithiophosphinates, prepared according to equation (38). These form dimeric units with approximately linear SAuS linkages, but the dimers are further associated into chains by intermolecular Au Au contacts as shown in Figure 7. When it is considered that the Au—Au distance in metallic gold is 276.8 pm, it is clear that the intramolecular and intermolecular Au—Au distances in these complexes of 276-310 pm and 305-340 pm respectively must involve some bonding interaction,7 and this has been confirmed by Raman spectroscopy.281... 

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