Reactions to Form Polylithiated Compounds

Reactions at a Group lA Metal Center 10.2.2.6. Reactions to Form Polylithiated Compounds 10.2.2.6.1. In Condensed Phases. 

Moreover, in deprotonation reactions with common alkyllithium bases (e.g. butyl-lithium), no side-products are formed, that increase the solubility of the polylithium compound. Also, product mixtures are only rarely observed with this method. Thus, the resulting polylithium compound can be isolated or crystallized more easily. This is why—in addition to Section II. E—only this section presents many visualizations of successful X-ray structural analyses of polylithiated compounds. 

In 1971 the second perlithio compound, C5Li4, was obtained by lithiation of 1,3-pentadiyne (7, 8). When the latter is treated with alkyl-lithium compounds in the absence of TMEDA, addition of alkyllithium reagents to one of the triple bonds is the main reaction, and no highly metalated products form. However with TMEDA, polylithiation takes... 

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