Cerium alkoxide isopropoxide

The alkoxides Ce(OR)4 are another well-developed class of Ce compounds. The alkoxide group plays an important role in stabilising the Ce(IV) state, witness the existence of [CeCp2(OBuOz] and [CeCp3(OBu )], when other Ce(IV) organometallics cannot be isolated. The isopropoxide is volatile in vacuo below 200 °C (its bis (isopropanol) adduct has six-coordinate cerium). General methods are available to... 

The differences in solubility of metal isopropoxides and their alcoholates have led to the crystallization of pure isopropoxide isopropanolates of some tetravalent elements. For example, zirconium tetraisopropoxide is a viscous supercooled liquid which dissolves in excess of isopropyl alcohol and crystallizes out in the form of pure white crystals which were characterized as Zr(OPr )4.Pr OH. Similarly tin tetraisopropoxide and cerium tetraisopropoxide have been obtained as crystalline alcoholates, Sn(OPr )4.Pr OH ° and Ce(OPP)4.Pr OH which were used as the starting materials for the synthesis of a number of new alkoxides. 

The isopropoxides of cerium and thorium also show higher association (3.1 and 3.8, respectively, in boiling benzene) than titanium, zirconium, and hafnium alkoxides. 

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]. 

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