Rubidium organometallic compounds

As discussed in Section 12.2, group 1A metals form ionic metal-carbon bonds. Organometallic compounds of group 1A metals other than lithium have metal-carbon bonds with less of a covalent character than the corresponding bonds in lithium compounds and tend to be especially reactive. Compounds of rubidium and cesium are rarely encountered outside the laboratory, so their toxicological significance is relatively minor. Therefore, aside from lithium compounds, the toxicology of sodium and potassium compounds is of most concern. 

Formation of such intermediates is favorable for lithium because it has a small ionic radius and is high in the proportion of p-character. Organometallic compounds of the other alkali metals (sodium, potassium, rubidium, and cesium) are more polar and more dissociated. They react essentially as solvated ions even in a hydrocarbon medium, yielding high 3,4 placement. 

Organolithium compounds have been more widely used than compounds of the heavier alkali metals. Smith has published an extensive review that focuses on the organometallic chemistry of sodium, potassium, rubidium, and cesium. An important textbook that covers the general aspects of organoalkali metal chemistry was written by Elschenbroich and Salzer. These publications, along with this article in the first edition of this encyclopedia, were used as foundational sources for this overview of the organometallic chemistry of the alkali metals. 

---