Barium alkoxides monomeric

Using a tetradentate ligand, Rees and Moreno have proposed the first example of a monomeric barium bis-alkoxide (26). The proposed solution structure (Fig. 2) was determined based on ciyoscopic and spectroscopic data. One notable characteristic of this monomeric barium alkoxide is that it is an ambient temperature liquid. Although the compound exists as a monomer in the solution state, oligomeric species prevail in the absence of solvent. This phenomenon has been ob-... 

Recently (33, 59), soluble monomeric alkoxides (aryloxides) of calcium and barium have been synthesized by the reactions of their iodides with the potassium salts of sterically hindered alcohols (phenols). 

Interest in the synthesis and structural characterisation of less common metalloorganophosphide systems has continued. A range of alkali metal complexes of the phosphide anion (48) has been prepared from the lithio-phosphide by simple metathesis with alkali metal alkoxides. The lithio-phosphide exists as a dimer, but crystallisation of the sodium and potassium drivatives in the presence of TMEDA results in the formation of monomeric species. The caesium triphosphenide (49), involving a phosphorus analogue of the allyl anion, has been prepared from the previously described sodium complex. Unlike the sodium and potassium complexes, which are monomeric, the caesium complex has a polymeric structure. A variety of arylphosphide complexes of magnesium, calcium, strontium and barium have been prepared and their solid state structures characterised. Cop-per(I)-, silver(I)- and gold(I)-complexes of the cyclo-(P ion have also... 

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