Olation Reactions

Dynamic and isothermal thermogravimetric measurements [1284] for the olation reactions... 

Werner and Surber2 used this olation reaction to assign configurations to the salts. The lilac-colored potassium salt, which crystallizes as either the di-or trihydrate, was first prepared by Werner and Surber.2... 

The recognition of H302 bridges provided an explanation for why it was the only cis-hydroxoaqua species that could undergo the so-called olation reaction to give dihydroxo species, i.e.,... 

A), strong, and centered hydrogen bonds.846 Heating of solid compounds (169) at 150°C leads to the formation of the dihydroxo-bridged dimers (170) (olation reaction Scheme 28).846 Stereoselectivity of the olation reactions for the [Cr2(chxn)4(/x-H307)2]41 complexes (chxn = (15,25)- or (15,25)-l,2-/nmv-cyclohexanediamine) has been discussed.847... 

The preparation and properties of many hydroxoaqua complexes of chromium(III) and cobalt III) were reported since the beginning of the century, but some of them cannot be used for growing single crystals. Rapid crystallization or recrystallization yields microcrystalline precipitates while slow crystallization is often obstructed by olation (reaction 8), isomerization and other slow substitution reactions. 

Olation reactions also take place in aqueous solution. A well known example is the olation of the Cr(III) aqua ion... 

The difference between the simple and the complex salts lies in the capability of the ions to deprotonate the water molecules associated with them. For simple ions this is not probable. The hydrolyzed and deprotonated metal cations form multinuclear complexes through oxolation-olation reactions discussed below. These reactions are dependent, not only on the pH, but also on the total metal concentration. By using the conditional constant approach this is illustrated as the dependency of log a(Fe(OH)) plotted as a function of the pH for a range of concentrations of Fe + ions in Figure 8.12. ... 

The axial coordination sites, trans to the Mo=0 bond, are less acid explaining the presence of water molecules inside the rings. As the condensation takes place at the equatorial positions, soluble inorganic chains are formed and are closed by a double olation-reaction. The formation of rings is probably due to an entropic factor since a cycUc conformation, rather than a linear chain, increases the entropy of the solvent, generates the elimination of two water molecules and reduces the interactions with the solvent by minimizing the surface. 

Fig. 11. The olation reaction. The solid lined squares indicate the original tetrameric units, and the dashed lines denote new ol bridges...

For the [Co(bipy)a] + ion, it was possible to separate the oxygenation and olation reactions so that the effect of dibridging upon the oxygenation could be investigated. The rate of conversion of the oxygenated species into the oxidized form was also measured. 

The dimer consisting of two edge-shared octahedra forms via an olation reaction between two singly hydrolyzed monomers (/i = 1) ... 

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