Lanthanum methoxide

The advantage of this method over the others described in the preceding sections is that the lithium chloride is soluble in methanol, making the separation of insoluble methoxides easily possible. The method was later extended by other workers for the preparation of methoxides of beryllium, " lanthanum,uranium, neptunium, vanadium, iron, ° and copper. ... 

Similarly, preparation of anhydrous and/or unsolvated lanthanide tris-acetylacetonates remained a challenge till 1965, as the efforts to remove ligated water from Ln()S-dik>3.2H2O (obtained from aqueous media) led to hydrolyzed products. However, pure tris-j6-diketonates of lanthanum, praseodymium, and neodymium could be easily synthesized by the reactions of their alkoxides (methoxides/isopropoxides) with 3 equivalents of acetylacetone (acacH) ... 

The methoxides and ethoxides of lanthanoids are insoluble solids. The derivatives of phenols and higher alcohols are amorphous or crystalline substances soluble in common organic solvents. Some of them (isopropoxides, tert-butoxides and derivatives of 2,6-di-tert-butylphenols) are sublimed in vacuum at 190-250 C. The cerium tetra-alkoxides with tertiary-radicals appear to be distillable liquids. The mixed alkoxide of lanthanum La(0C3H7-i)2(0CH2C4H70) containing the residue of tetrahydrofurfuryl alcohol OCH2C4H7O and the isopropoxy groups remains liquid at room temperature [14]. 

A lanthanum-chromium methoxide complex was prepared by Bilger et al. (1997) for the synthesis of lanthanum chromite (LaCrOs) powder. The starting materials for the two cations were lanthanum trichloride heptahydrale and chromium trichloride hexahydrate. The methoxide complex was hydrolyzed, and the product peptized to obtain a stable sol. Calcined gel particles gave rise to stoichiometric LaCrOa powders (see also Mechanical Dispersion of Sols ). 

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