Mixed-ligand halides

Halides, 7 1-26 actinide elements, 2 195-233 anion dependence, 39 139 berkelium, 28 48, 51-53 beryllium, 14 255-332 binary, 35 237-246, 274-280 decomposition, 35 277 dichalcogen dihalides, 35 279-280 equilibrium studies, 35 242 mixed-ligand halides, 35 244-246 reactions, 35 246 selenium halides, 35 240-241... 

The presence of halides in the coordination sphere with aldehydes is important as zinc halides are typically used in organic synthesis as organic carbonyl activators. Large excesses of aldehydes and anhydrous zinc halides were necessary. Both monomeric and polymeric structures with halide bridges were observed. Tetrahedral geometries were observed for mixed ligand, aldehyde, and halide complexes.353... 

Heterocyclic nitrogen donors and their adducts with zinc chloride have been studied.623,624 A large number of other ligand systems have also been characterized, for example, zinc halide adducts of 2,2-dimethylpropane-1,3-diamine and hexamethylphosphoramide have been studied.625,626 The formation of mixed ligand complexes with chloride and substituted pyridines has been studied.627 The zinc tris(pyridyl) chloride anion has also been structurally characterized.628 Manganese(II) ions have been used to probe the stereochemistry in reactions of zinc halides with pyrazine.629... 

Mixed-ligand anions [RC=CAuX] are rare in organogold chemistry. Selected examples have been obtained from reactions of [RC=CAuL oligomers with halides Q+X, from Q[Au(acac)2] salts with alkynes, followed by acids HX in the molar ratio 1 1 1, and from complexes (tht)AuCl (tht = tetrahydrothiophene) or [(Ph3P)2C]AuCl with an alkyne and a base (1 1 1). Known examples of products include salts Q+[HC=CAuCl/Br]-72 and [(Ph3P)2CH]+[PhC=CAuCl]. 52,53 Anions with mixed alkynyl/aryl substituents are present in... 

Mixed ligand complexes of the type [NiX(bipy)(PPh3)] (X = halides, jUeff = 2.1 BM) have been reported.311... 

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... 

A convenient method for the stepwise substitution of halide groups by alkoxide ligands involves the use of alkoxysilanes. By this method, Handy and coworkers have synthesized and studied a large number of mixed alkoxy halides of molybdenum and tungsten (equation 39).131-134 The method has also been used for the preparation of phenoxy and substituted phenoxy derivatives.133... 

The alcoholysis of derivatives that do not initially contain alkoxide ligands is of special importance for the preparation of alkoxide halids. It is also an efficient synthetic route to mixed-ligand complexes of chromium [538, 523, 1189] ... 

The molecular complexity of molybdenum (IV) alkoxides is determined by the size and ramification of the alkyl group — the polymeric (R = Me), dimeric (CN = 5, two bridging OR-groups, R = Pr ) with a double metal-metal bond, and even monomers (R = Bu ). The first representatives of W(OR)4 homologous series are tetramers with the [Ti4(OMe)16]-type structure. The derivatives of ramified or bulky alcohols are known only as mixed-ligand complexes (such as dimeric solvates of alkoxide halids with alcohols, various alkoxide hidrides and monomeric complexes with phenantroline, see Table 12.19). 

The halides participate as terminal and bridge ligands and can be included in inner and external spheres of this kind of complex. A few examples of compounds with such terminal ligands are the boron ammines [BX3 NH3], [BX2(NH3)2]X, BX(NH3)3]X2, and [B(NH3)4]X3 (X = F, Cl, Br, I). Halides form part of many mixed-ligand carbonyl complexes, for example, Fe(CO)4I2 and polyhalide anions with various elements [4], In this respect, the structure of the anion [Re2Clx]2 provides important information the Re — Re bond is present and the chlorine atoms have a bridge function [4]. 

More stable mixed-ligand five-coordinated species 104a, b were synthesized by reaction of Sn(OAc)4, with o-mercaptophenol followed by halide salt addition (equation 18)336. 

Evans et al. sequentially reacted the Nd carboxylate precursor Nd[C>2CC (CH3)2CH2CH3]3 % first with DEAC and then with TIBA. By this reaction catalytically active systems are obtained which polymerize IP. In the first reaction step in which Nd carboxylate is reacted with DEAC mixed ligand complexes are formed which contain neodymium and aluminum as well as halide and ethyl groups. Upon crystallization NdC -based compounds are obtained in which solvent is coordinated. These compounds exhibit a more complex... 

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