Halide complexes of

Magnesium forms few halide complexes of the type MX4 , though [NEt4]2[MgCl4] has been reported examples of for the heavier... 

Similar structural diversity characterizes the heavier halide complexes of the group. The... 

An extensive range of mono- and binuclear halide complexes of platinum and palladium exist. Of the tetrahalometallate(II) ions, some like PtF4 and Pdl4 are elusive, the latter only having been characterized in solution. 

Table 4 Important geometrical parameters in the structures of the halide complexes of 163 and 164... 

Axelrad, G., Laosooksathit, S., and Engel, R., Reactions of copper halide complexes of trivalent phosphorus with vinylic halides, /. Org. Chem., 46, 5200, 1981. 

Silver(I) halide complexes of oA could not be prepared. The phosphine ap, however, reacts with silver iodide to give a colourless, unstable, non-conducting compound of empirical formula Agl(ap). This compound reacts with excess ap to give the stable 2 1 adduct Agl(ap)2- Silver bromide and silver chloride react directly with the ligand to give similar 2 1 adducts. These complexes are essentially monomeric, contain three-coordinate silver (I) and uncoordinated olefinic groups. The structure of the 1 1 adduct is unknown. 

A variety of behaviour is observed in the reactions of [Na(THF)4][cyclo-P5 Bu4] with phosphine halide complexes of the nickel triad." Of particular interest is the formation of the complex Ni(cyclo-P5 Bu3)(PEt3)2 in which the... 

A large number of halide complexes of thallium(III) have been prepared by precipitation of the complexes from solution with a suitable cation, eg, H+, (C2H5)4N+, (C6H5)4As+, and K+. Both four-coordinated [HXJ" and six-coordinated [TlXJ3 ions exist in solutions and in solid states. 

The nickel halide complexes of Schiff bases (113) and (114) obtained from benzaldehyde and a number of diamines have the formula NiX2L (X = Cl, Br, I) with pseudotetrahedral structure in the solid state and in solution as well.954... 

Carbonyl halide complexes of platinum(IV) are less common. The reaction of [Pt(CO)2]s with chloride ion in an aqueous solution of iron(HI) ions gives Pt(CO)H2Cl2, which adds chloride to give Pt(CO)H2ClJ.313,314 Addition of chlorine to a thionyl chloride solution of Pt(CO)2Cl2 at room temperature results in the rapid formation of Pt(CO)Cl (equation 106), which shows a carbonyl stretch at 2191 cm-1. The yellow-orange compound is stable toward Cl- but reacts with water to form C02.315... 

High oxidation state silver halide complexes of chloride, bromide and iodide tend to be even more unstable with respect to reduction and have not been studied in detail.549... 

The stability constants in melts of NH4N03- H20 of ZnX+, ZnX2 (n = 1-3 X = Cl or Br), CdX+, CdX2 (n = 1.5-3 X = Cl or Br) and HgX HgX2 (n = 2.5 X = Cl or Br) have been determined.950,931 The behaviour of zinc is peculiar if the Ki and K2 values are compared with those of cadmium and mercury. The stability constants increase with temperature and the bromide is more stable than the chloride, trends which are opposite to those normally observed for the halide complexes of most metals in anhydrous or aqueous melts. The data also show... 

Much work has been devoted to the halide complexation of these elements in non-aqueous media. Equilibrium and calorimetric measurements for the formation of the [MX ](n-2) (M = Zn or Cd X = Cl, Br, I or SCN n = 1-4) anions in dimethyl sulfoxide (DMSO) have shown that stability constants follow the same order, but are much larger than those found for aqueous solution zinc exhibits an enhanced hardness as an acceptor in DMSO as compared to cadmium. Calorimetric measurements indicate a change from octahedral to tetrahedral coordination with increasing halide concentrations.1002-1006... 

Halide ligands are found in homoleptic complexes as well as in mixed ligands systems. Halide complexes of Ir(IV) such as [IrCl6]2 [16918-91-5] are readily reduced to Ir(III) species, eg [IrCl6]2 [14648-50-1], in neutral or basic solution, or in the presence of reducing agents such as KI, oxalate, or... 

The simplest and most generally useful synthetic method for metal diketonates is from the diketone and a metal such as a halide, hydroxide, oxide, sulfate, carbonate, carboxylate, etc. in a variety of solvents such as water, alcohol, carbon tetrachloride or neat diketone. Since many / -diketones are poorly soluble in water, use of an organic solvent or cosolvent may be helpful. Optionally, a base such as sodium carbonate, triethylamine or urea may be added. Addition of a base early in the reaction converts the diketone to its conjugate base, which usually has greater solubility in aqueous media.159 In some cases, metal halide complexes of the diketone form as intermediates, e.g. SnCl4(MeCOCH2COMe), which has been formulated as... 

Halide complexes of this group react with carbanions to form stable alkylmetalloporphyrins.27 The thallium atom is significantly displaced (0.98 A) from the N4 plane with a large T1—N,, distance (2.29 A) in Tl(TPP)Me, formed by the reaction of H2TPP and MeTl(OCOMe)2 (Scheme 5). Monovalent thallium porphyrin complexes are also known.17 They can be prepared by treating a porphyrin with thallium(I) ethoxide in THF.29 Unlike the other Group IIIB metalloporphyrins, [Tl i Por) is easily hydrolyzed. 

In contrast to nickel, simple homoleptic Tpx or Bpx, and heteroleptic pyrazolylborate-halide complexes of palladium and platinum are largely unexplored. Indeed, while for 3d metals these are "standard" targets for each successive generation of poly(pyrazolyl)borate ligand, for the... 

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] ... 

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