Organometallic uranium(IV) fluoride complexes: preparation using protonolysis chemistry and reactivity with trimethylsilyl reagents.

Reaction of the uranium alkyl complex (C(5)Me(5))(2)UMe(2) (1) with Et(3)N.3HF in toluene in the presence of a donor ligand (pyridine or trimethylphosphine oxide) results in gas evolution and the formation of the uranium(IV) difluoride complexes (C(5)Me(5))(2)UF(2)(L) (L = NC(5)H(5) (2), Me(3)P=O (3)). Similarly, reaction of (C(5)Me(5))(2)U[kappa(2)-(C,N)-CH(2)Si(CH(3))(2)N(SiMe(3))] (5) with Et(3)N.3HF in toluene gives the uranium(IV) amide-fluoride complex (C(5)Me(5))(2)U[N(SiMe(3))(2)](F) (6). The fluoride complex (C(5)Me(5))(2)UF(2)(NC(5)H(5)) (2) shows versatile reaction chemistry with a variety of trimethylsilyl reagents and demonstrates that the U-F bond provides an attractive synthetic strategy for accessing new functional groups that are not available from alkoxide or chloride complexes.