摘要 |
The present invention concerns an addition compound of a carboxylic acid and a rare earth or gallium halide or a rare earth or gallium halogenocarboxylate of the same acid. This compound is obtained by a process in which a rare earth or gallium carboxylate is reacted with HX, X representing a halogen, in a solvent selected from alkanes, cycloalkanes and aromatic solvents and mixtures thereof, the reaction being carried out with an X/rare earth or gallium atomic ratio of less than 3 when preparing a halogenocarboxylate. The invention also concerns a second process for preparing an anhydrous addition compound of a rare earth or gallium halide and a nitrogen or oxygen donor compound in which an addition compound of a carboxylic acid and a rare earth halide of the type described above is prepared, and a nitrogen or oxygen donor is added to the medium obtained, the donor being selected from linear and cyclic aliphatic oxides, aliphatic glycol ethers, aliphatic ketones, aliphatic amides, aliphatic nitrites, aliphatic sulphoxides and hexamethylphosphotriamide. |