Lanthanide trichlorides alcoholates

Finally, in this section on alcohols, we should mention investigations in which the trichloride/alcohol systems are acknowledged to be not anhydrous. Solubilities of yttrium trichloride and of most of the lanthanide trichlorides have been determined in 96.8% ethanol over the temperature range 20-60°C (289), while the solubilities of the hydrates LaCl3-7H20 and CeCls-BHjO have been determined in an extensive range of alcohols at 25°C, with a few data at 35° and at 45°C (290). 

Solvates of the monohydroxylic alcohols have been extensively studied. The expected pattern of more solvent molecules per chloride molecule is reported for the lanthanide and yttrium trichlorides. For scandium trichloride, the existence of ScCl3-2EtOH and ScCl3-2C6H13OH compares unexpectedly with the tris-alcoholates reported for the n-C6... 

In a subsequent study of reaction parameters, lanthanide ions were found to promote the selective reduction of conjugated aldehydes in the presence of noncon-jugated aldehydes in aqueous ethanol. Erbium trichloride was the preferred catalyst, usually where the solubility of cerium trichloride in solvents such as isopropyl alcohol was unfavorable (Gemal and Luche, 1981b). The authors described the interaction between the lanthanide and the intermediate substrate as a chelating effect . 

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