Ylides with gold

Bis-ylides, with gold , 2, 272 [5-5]Bitrovacenes, properties, 5, 51 [7-7]Bitrovacenes, properties, 5, 51 Blapharocalyxin E, via lead triacetates, 9, 387 Block co-polymers... 

Dialkynyl ligands, in platinum(II) complexes, 8, 545 iV,iV-Diallylamine, via allyindium reagents, 9, 703-704 Diallyl clusters, in trirutheniums and triosmiums, 6, 773 gem-Diallyl esters, via indium-mediated allylation, 9, 677 Diallyl ethers, isomerization, 10, 90 Diamagnetic ylides, with gold(II), 2, 278 Diamides... 

Phosphorus—selenium bonds, alkyne additions, 10, 782 Phosphorus—sulfur bonds, alkyne additions, 10, 781 Phosphorus ylides with gold(I), 2, 275 with trinuclear Os clusters, 6, 740 Phosphoylides, actinide complexes, 4, 203 Photoacoustic calorimetry, in thermochemistry, 1, 612-613 Photoactive molecular devices, and -[RefCO) ,] fragment, 5, 886... 

The compound 70 has also been reported showing the ambident character (both C- and N-coordination) of the cyano-stabilized ylide as ligand. The authors have also transposed their work concerning the keto-bis-ylide and palladium, with the synthesis of the C-bonded complex 71 or the new cycloplatinated or-thometallated compound 72. The latter by various treatments allows one to obtain other ylidic cationic complexes of platinum such as 73. A C,C,C-terdentate coordination of the keto bis-ylide, already observed with the palladium is also obtained from the reaction of 73 with gold derivatives. 

The compound 86 constitutes an interesting compound in which a bis keto-ylide coordinates both a palladium (through an aryl and an ylidic carbon) and a mercuric center (through an yfidic carbon) [89,110]. This C,C,C-terdentate coordination has also been observed with gold complexes. 

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.

Functions [R2Au] are also present in the large family of gold(i) complexes of phosphonium, arsonium, and sulfonium ylides . Section 2.05.6 is dedicated to this class of complexes, where dinuclear compounds with gold in the oxidation state +2 are also common. 

Unusual aurophilic bonding between gold in different oxidation states appears to be responsible for the adduct formation between (G6F5)3Au and cyclic ylide complexes with gold in the oxidation state +1 and +2 and in related compounds with an ionic structure (Scheme 24)155-157... 

Cyclic amino-carbenes, in molybdenum carbonyls, 5, 457 Cyclic bis(phosphine) dichlorides, with iron carbonyls, 6, 48 Cyclic carbenes, as gold atom ligands, 2, 289 Cyclic carbometallation, zirconium complexes, 10, 276 Cyclic carbozirconation characteristics, 10, 276 intermolecular reactions, 10, 278 intramolecular reactions, 10, 278 Cyclic dinuclear ylides, and gold , 2, 276 Cyclic 1,2-diols, intramolecular coupling to, 11, 51 Cyclic enones, diastereoselective cuprate additions, 9, 515 Cyclic esters, ring-opening polymerization, via lanthanide catalysis, 4, 145 Cyclic ethers... 

In the last section reactions were presented in which the bridging ylide ligands do not appear to participate and the diauracycle remains intact. This is not the case when the starting 6w-ylide reacts with gold(I) derivatives, which are either cationic... 

A related dinuclear species 77, recently described, constitutes the first dinuclear gold(I) complex with heterobridged phosphor-1,1 -dithiolato moieties and bis(ylide) bridging ligands [ 102]. It is obtained by reaction between [ AuS2PPh2] and the diylide gold complex 74 (R=Me). No intermolecular Au-Au interaction is observed in 77 but the oxidative addition of chlorine to the product leads to a new complex 78 in which a single bond is formed between the two Au(II) centers (Scheme 26). 

The reaction of the dinuclear gold(I) amidinate complex, [Au2(2,6-Me2Ph-form)2], with Hg(CN)2 (1 2 stoichiometry) in THF forms a 2D coordination polymer, [Au2(2,6-Me2Ph-form)2]-2Hg(CN)2 2THF, not the expected oxidative-addition product of the type formed vdth the ylides. White crystals and a yellow powder are formed. 

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... 

Gold(I) ylides are oxidized in 0.1 M [Bu4N]BF4/THFat low potentials of +0.11 and + 0.23 V vs. Ag/AgCl (quasi-reversible). The dinuclear amidinate oxidizes under the same conditions at + 1.24 V vs. Ag/AgCl (reversible). These large differences in chemical character of the dinuclear gold(I) complexes appear to explain the widely different behavior of these compounds and especially toward the reaction with mercury cyanide. 

Neutral ylide, isocyanide and carbene pentafluorophenyl gold] 111) complexes with the general formulae trans-[Au]C6F5)X2]CH2PR3)[ ]PR3 = PPh3, PPh2Me, PPhMe2),... 

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