Coordination chemistry halides

Although redox processes are sometimes observed in metathetical reactions with metal halides, the pyramidal dianion [Te(NtBu)3] has a rich coordination chemistry (Scheme 10.8). For example, the reaction... 

The coordination chemistry of Zn" and Cd", although much less extensive than for preceding transition metals, is still appreciable. Neither element forms stable fluoro complexes but, with the other halides, they form the complex anions [MX3] and [MX4] , those of Cd" being moderately stable in aqueous solution. "" By using the large cation [Co(NH3)6] + it is also possible to isolate the trigonal bipyramidal [CdCls] "... 

The coordination chemistry of hydrogen cyanide, cyanogen and cyanogen halides. B. Corain, Coord. Chem. Rev., 1982, 47,165-200 (111). 

The diazaphosphane or aminoiminophosphane ligands with a NPN framework are another subclass of cyclophosphazenes. These compounds with both phosphorus in oxidation state (111) [104-110] and (V) [111-112] have been employed in the synthesis of four membered heterocycles and coordination chemistry with group 13 derivatives. Several complexes of trivalent phosphorus derivatives with both aluminum halide and alkyls are known as illustrated for 48 in Scheme 21 [113-119]. The structure determination of 48 confirms the formation of a four membered metallacycle [116, 117],... 

Lithium halides disrupt the dimeric structures of 59a or 59c to give distorted cubes of the type 60, in which a molecule of the lithium halide is entrapped by a Li2[E(NtBu)3] monomer.164,165 Similar structures are found for the MeLi, LiN3 and LiOCH=CH2 adducts of 59a.166 168 The pyramidal dianion [Te(N Bu)3]2 has a rich coordination chemistry,169 171 although redox processes are sometimes observed in metathetical reactions with metal halides. For example, reaction with PhPCl2 gives a spirocyclic Te(IV) complex of the [PhP(NtBu)3]2 dianion,163 while treatment with Sn(II) salts generates a complex with a four-coordinate Sn(IV) = Te functionality.172... 

Herrmann WA, Brossmer C, Reisinger CP, Riermaier T, Ofele K, Beller M (1997) Coordination chemistry and mechanisms of metal-catalyzed C-C coupling reactions. Part 10. Palladacycles efficient new catalysts for the Heck vinylation of aryl halides. Chem Eur J 3 1357-1364 Iyer S, Jayanthi A (2001) Acetylferrocenyloxime palladacycle-catalyzed Heck reactions. Tetrahedron Lett 42 7877-7878 Iyer S, Ramesh C (2000) Aryl-Pd covalently bonded palladacycles, novel amino and oxime catalysts di- x-chlorobis(benzaldehydeoxime-6-C,AT)dipalla-dium(II), di- x-chlorobis(dimethylbenzylamine-6-C,A)dipalladium(II) for the Heck reaction. Tetrahedron Lett 41 8981-8984 Jeffery T (1984) Palladium-catalysed vinylation of organic halides under solid-liquid phase transfer conditions. J Chem Soc Chem Commun 1287-1289 (b) idem,... 

We have compiled important preparations of heteroaryl halides, boranes and stannanes for each heterocycle. The large body of data regarding palladium-mediated polymerization of heterocycles in material chemistry is not focused here neither is coordination chemistry involving palladium and heterocycles. 

Coordination complexes that have metal halide clusters as their central cations represent a unique branch of coordination chemistry. The [M6X12]" cluster... 

Chesnut, D.J., Kusnetzow, A., Birge, R.R. and Zubieta, J. (1999) Solid state coordination chemistry of the copper halide- and pseudo-halide-organoamine system, Cu-X-[(bis-2,3-(2-pyridyl) pyrazine)] (X = C1, Br, CN) Hydrothermal synthesis and structural characterization. Inoig. Chem., 38, 2663—2671. 

Coordination chemistry of aluminum prior to 1970 was included in Wade and Banister s account of the element.1 There are thorough reviews of aluminum chemistry with particular reference to oxygen compounds, halides and their adducts, which cover the period prior to... 

The coordination chemistry of indium(I) received little or no attention for many years, largely no doubt because of the lack of suitable starting materials. The indium(I) halides can be easily prepared,1 but are intractable materials which readily undergo hydrolysis and disproportionation (but see Section 25.2.2.1). The only known organoindium(I) compounds are the cyclopentadienyl and methycyclopentadienyl derivatives,8 and the former has proven a useful starting point for some synthetic work. Electrochemical methods have been used either to reduce higher states, or to oxidize the metal in the presence of suitable ligands, in order to produce indium(I) species. 

As with indium, the literature contains a number of surveys of the general inorganic1 and organometallic chemistry of thallium,273 and the reviews of this element already cited are also concerned with the adducts of the halides and pseudohalides,5 and with other aspects of the coordination chemistry.6 A monograph by Lee provides a most useful treatment of the literature up to 1970.274 The application of thallium compounds in organic synthesis has been discussed.275 276... 

This chapter has been devoted to the coordination chemistry of titanium and has made no attempt to describe the more basic chemistry of this element. References to alloys, to the simple halides and oxyhalides, the oxides, sulfides, selenides, tellurides, nitrides, azides, phosphides, arsenides and antimonides are well reviewed by Clark,14 and the recent text by Greenwood and Earnshaw180 contains a good section on titanium. 

Niobium and tantalum compounds form adducts with virtually all types of neutral ant anionic donors. The coordination chemistry of the higher halides is widely developed, and thei activity as Friedel-Crafts catalysts is another manifestation of their Lewis acidity. The stron acceptor capacity of the high valent metal compounds tends to favor the formation of dimers and sometimes of higher condensation products, which competes with coordination with othe donor molecules. Numerous simple anionic or heteropolyanionic species, but little cationi chemistry, and no simple metal salts, are known. 

The coordination chemistry of silver has historically been centred on the reaction of silver(I) ions with N-donor ligands and halides. However, an extensive chemistry now exists for P- and S-donor ligands, whilst for O-donor ligands only weak complexes are generally formed and they have been studied in much less detail. Based on the reactivity and stability of its coordination complexes, the silver(I) ion has been characterized as a class B or soft acid, for which the following stability order is observed N P>As>Sb 0 S Se Te FComparative studies between ligands with these donor atoms allowed the relative stability of silver bonds to be determined as P > S > N > O. 

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