Synthesis and Reactivity of Ln-C Bonds

The synthesis, structure, and physical and chemical properties of organo-lanthanide complexes containing only polyhaptocyclopentadienyl and cyclooctatetraenyl metal-carbon bonds are fully covered in other reviews (5-7). This section will focus on lanthanide-carbon single bonded species only. Ln—C single bonds are found almost exclusively in only two types of complexes homoleptic complexes, and heteroleptic 

X-ray structural analysis, but the area of lanthanide alkylidene and alkylidyne complexes is likely to develop significantly in the next few years 

This was a clear example of the potential of organolanthanides to display unique reactivity patterns. The tert-butyl results also demonstrated that one need not necessarily expect the principles of organotransition metal chemistry to apply exactly to organolanthanide compounds. Indeed, one of the exciting aspects of this young organolanthanide area is that the principles of reactivity are still being established, i.e., current experiments 

Ln—C bonds and has been usefully extended to a variety of other organolanthanide syntheses (see Sections IV,B. V,C, and VII,A). 

In addition to the formally four-coordinate homoleptic complexes already described, six-coordinate species have been obtained using methyl ligands. Treatment of lanthanide trichlorides with a greater than sixfold excess of CHaLi in the presence of tetramethylethylenediamine (TMEDA) forms complexes containing an octahedral Ln(CHa)6 unit [Eq. (S), Ln = Pr, Nd, Sm, Er, Tm, Yb, Lu] (27-29). X-ray crystallographic studies 

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Synthesis and Reactivity of Organolanthanide Complexes Containing Ln-C Bonds... 

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