Organouranium chemistry

For example, Henry Gilman attempted to synthesize compounds like tetramethyluranium, and others worked on uranium metal carbonyls, but none of the efforts met success due to organouranium instability.

Ernst Otto Fischer in 1962 discovered tetracyclopentadienyluranium Cp4U by reaction of KCp with UCl4 (6% yield) as a compound stable in air as a solid but not in solution.

In 1968, the group of Andrew Streitwieser prepared the stable but pyrophoric compound uranocene (COT)2U, which has an atom of uranium sandwiched between two cyclooctatetraenide anions (D8h molecular symmetry).

A close relative that does have sufficient reactivity, obtained by reaction of uranocene with uranium borohydride is the half-sandwich compound (COT)U(BH4)2 discovered in 1983 by the group of M.J. Ephritikhine.

Several anionic homoleptic uranium(V) alkyls are known in the form of their lithium etherate salts, including [UR8]3–, with R = Me, CH2TMS, CH2tBu.