Halides double

Brown, I. D. and Duhlev, R. (1991). Divalent metal halide double salts in equilibrium with their aqueous solutions II. Factors determining their crystal structures. J. Solid State Chem. 95, 51-63. 

Treatment of polymer films by reactive gases or reactive volatil compounds allows to easily modify polymers containing alcohols, hydroperoxides, carboxylic acids (or acids halides), double bonds or piperidine groups. New functional groups as organic nitrites, nitrates, iodides, acid halides (Cl, F), amides, esters, peresters and nitroxyl radicals can be generated by a single reaction or by combination of two consecutive treatments. The reactions are very efficient on thin films (ca 50-100 pm) and can be controlled by transmission and reflexion 1R spectroscopy. 

Friend88 specifically criticized Werner s theory and emphasized the differences between his own latent valencies and Werner s Nebenvalenzen. He applied his new theory of valency to ammonium salts, metal ammines and halide double salts , and he proposed that for hexacoordinate central atoms a hexatomic shell forms around the metal but that all the elements or groups are joined together by latent valencies and not necessarily to the metal itself. In 1916, Friend applied his cyclic theory of complexes in detail to the structures of the chlorides of hexaamminecobalt(III), chloro-pentaamminecobalt(III) and dichlorotetraamminecobalt(III) and emphasized four basic differences between his theory and Werner s.89... 

Changing the concentration of either reactant affects the rate. For example, doubling the concentration of either the nucleophile or the alkyl halide doubles the rate. Doubling the concentration of both reactants increases the rate by a factor of four. 

Both benzyl and allyl halides are rapidly hydrogenolyzed. Cleavage can be achieved selectively in the presence of aryl and alkyl halides. Double bond isomerization can often prevent any stereoselectivity in allylic cleavages. 

As we have seen, a study of the kinetics of a reaction is one of the first steps undertaken when one is investigating the mechanism of a reaction. If we were to investigate the kinetics of the reaction of ferf-butyl bromide with water, we would find that doubling the concentration of the alkyl halide doubles the rate of the reaction. We would also find that changing the concentration of the nucleophile has no effect on the rate of the reaction. Knowing that the rate of this nucleophilic substitution reaction depends only on the concentration of the alkyl halide, we can write the following rate law for the reaction ... 

Figure 32. Stereodrawing of the crystal structure of 3.2 (or 3.3) showing the accommodation of a single column of (n-CjH7)4N ions in a channel running parallel to the [101] direction. The host structure is built from selenourea-halide double ribbons and bridging selenourea molecules. Note that the double ribbons lie close to the (020) planes and are cross-linked by the bridging selenourea molecules. Broken lines represent hydrogen bonds, and atom types are distinguished by size and shading.

Orthophosphates crystallise not only as tribasic, monohydrogen or dihydrogen add salts, but also as oxide, hydroxide or halide double salts. Calcium salts, for example, include oxyapatite, hydroxy-... 

Doubling the concentration of the alkyl halide doubles the rate of the reaction, but changing the concentration of the nucleophile has no effect on its rate. This knowledge allows us to write a rate law for the reaction ... 

Systems are known which will reduce most of the organic functions (amides, carboxylic acids, nitriles, nitro, halides, double and triple bonds, aromatic rings, for instance). In most cases, the true catalyst is formed in situ by reduction of the metal with the hydride. Actually, very little is known of the mechanisms of those transition metal-assisted hydride reductions. Catalyzed reductions with NaBH4 have been reviewed [7]. 

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