Gold complexes alkyl

The few complexes of these metals where the only ligands are alkyls or aryls are ill characterized, readily oxidized, thermally unstable, and frequently explosive. The products of their thermal decompositions may be complex but almost always involve formation of intermediate alkyl or aryl radicals [155, 156]. The alkyl and aryl complexes of these metals wUch have other ligands attached to the metal are more stable, and in particular, a considerable chemistry of stable alkyl gold complexes is known. 

Unlike alkyl-gold bonds the Au—C bonds in pentafluorophenyl compounds are more resistant to cleavage by protic acids, giving more chemical integrity to the complexes. 

Gold complexes of alkyl phosphonates and ammonia are additives for high pressure organic lubricants. Their precise structure does not seem to be known.119 Solutions of Na[AuCl4] 2HzO are used in electrodeless gold plating.120... 

The effect of the alkyl group, R, on the rate of reaction (42) in solvent dioxan may be seen from Table 34. Relative rate coefficients are given in Table 35, and show that for all the mercuric salts used, the order of reactivity of the gold complexes is that of increasing electron release by the group R, viz. 

The ferrocenylphosphine-silver complex catalyzes the aldol-type reaction of tosylmethyl isocyanide 71 with aldehydes with higher stereoselectivity than the gold complex (Scheme 2-59) [84]. The reaction with several aldehydes produces trans-4-tosyloxazolines 72 in up to 86% ee, which can be converted into optically active l-alkyl-2-aminoethanols by reduction with LiAlH4. 

It has been noted that metal-carbon triple bonds behave in a similar way as alkynes with respect to jr-complex formation13,15. Various heterometallic gold complexes with bridging carbyne ligands reflect this analogy. Alkylidyne complexes like [W(=CR)(CO)2( 5-C5H5)], [W(=CR)(CO)2( 75-C2B9H9R )] (R = alkyl, aryl, amino R = H, Me) readily... 

Bibenzyl is formed in a yield of 22% when a degassed solution in acetonitrile of benzyl chloride, an electron donor such as triethylamine and a catalytic amount of the gold complex 88, is irradiated. The gold complex (88) is described as a potent new photocatalyst for such systems and performs better than existing catalysts. The mechanism of the process has been shown to involve direct halogen transfer as shown in equation 9. The resultant alkyl radicals then yield the final product. A similar reaction operates with 1-bromopentane when it is irradiated under the same conditions This yields -decane178. 

Tetraalkylaurate(lll) complexes were prepared by alkylation of neutral alkyl-gold(lll) complexes by alkyllithium (Eq. 5.9) [32-34]. 

The preparation of two cyclo-octatetraene-gold complexes, (ct)AuCl and (cot)-AU2CI4, has been reported. The structures of biscyclo-octatetraenyl complexes of titanium, vanadium, thallium, and uranium, were deduced from their i.r. spectra. Protonation of (p-cyclo-octatetraene) (p-cyclopentadienyl) complexes has been studied. For the ruthenium and osmium complexes protonation occurs on the eight-membered ring to give CgH moiety co-ordinated to the metal atom via both an T -alkyl and an olefin-metal bond. For the cobalt and rhodium complexes a bicyclic cation (287) is produced which undergoes isomerization to the monocyclic (288). ... 

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