Halide complexes dinuclear

Homoleptic complexes with bidentate C C donor ylide derivatives are well known. Oxidative addition of some gold(I) [Au2 (CH2)2PR2 2] species by addition of halogen, pseudo-halogen, or alkyl halide affords dinuclear Au(II) complexes which... 

The possibility of formation of dimeric structures should be taken into account in the syntheses of metal-halide complexes of other ligands. In this respect, the transformation (3.72) is interesting and representative, in which not only monomeric mononuclear 637, but also dinuclear 638 complexes were isolated and their structures determined by x-ray diffraction [89] ... 

Other synthetic routes reported involve the interactions of trifluoro-phosphine metallates and iodine (method E), displacement of carbon monoxide, alkenes, etc. by PF3 from the corresponding halide complexes (method F), addition of PF3 to dinuclear halogeno-bridged PF3 complexes at low temperatures (method G), and treatment of a metal hydrido- PF3 complex with iodoform (method H). 

Such aquo complexes react with triphenylphosphine yielding the corresponding phosphino compound. It is noteworthy that while the dinuclear platinum complexes do not react with water to produce the hydroxo compound and the formation of this hydroxo compound requires the refluxing of the halide complexes with KOH or NBU4OH for 24 hours, the silver derivatives decompose in solution with NBU4OH and react with water under mild conditions to form the hydroxo complex. Similarly, while the dinuclear platinum complexes do not react, for instance, with tht to cleave the bridging Pt(y(i-X)Pt system, the aquo silver compound reacts with tetrahy-... 

Most complexes of this oxidation state are derivatives of the rhenium(III) halides. They are classified according to the other ligands (if any) that are present. For example, ReChfPRjlj will be found under phosphine complexes rather than halide complexes . Mononuclear complexes of rhenium(III) are mostly of the types [ReX2L4]" and ReXjL, but rarely [ReX4L2] . Additionally, two very important classes of complexes exist that are derivatives of the quadruply bonded dinuclear [RcjXg] and doubly bonded trinuclear [RejX,2] anions (X = Cl, Br or I). ... 

Harutyunyan et al. investigated the formation of the chiral Cu(I)-diphosphine complexes, as part of a comprehensive mechanistic study on the Cu(I)-catalysed ACA of Grignard reagents to a,p-unsaturated carbonyl compounds [127]. Based on NMR, ESI-MS, IR, electrochemistry and X-ray ciystaUography measurements, they concluded that halide-bridged dinuclear copper complexes Cl (Scheme 30) are formed and persist in the solvents typically used for the ACA (Et20, tBuOMe and CH2CI2). 

Li, D., Che, C.-M., Kwong, H.-L. and Yam, V.W.-W. (1992) Photoinduced C-C bond formation from alkyl halides catalysed by luminescent dinuclear gold(I) and copper(l) complexes. Journal of the Chemical Society, Dalton Transactions, 3325-3329. 

The majority of gold(I) carbene complexes are pure organometallic compounds and the are out of the scope of this work. Some halide or triphenylphosphine carbene complexes are known and they will be considered here. Nucleophilic addition of alcohols or amines to gold-coordinated isocyanides is one of the best-established methods to obtain gold carbene derivatives. The reaction of H[Au(CN)2] with propene oxide and estirene oxide yields (cyano)carbene complexes (380) avoiding the intermediate step.2257 A cyclic carbene compound is obtained by reaction of a dinuclear isocyanide with amine (Scheme 32).2258... 

The complex [Au2(PPh3)2] has been prepared by reduction of [AuI(PPh3)] with sodium napht-halide. Its core unit is isoelectronic with mercurous halides Hg2X2 but, curiously enough, it has a dinuclear trans bent structure with d(Au—An) = 2.76 A and a Au—Au—P angle of 129°.3325 There is no confirmation as yet of the original preliminary report. 

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