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

摘要

Reaction of the uranium alkyl complex (C_5Me_5) _2UMe_2 (1) with Et_3N·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 _5Me_5)_2UF_2(L) (L = NC _5H_5 (2), Me_3PO (3)). Similarly, reaction of (C_5Me_5)_2U[κ~2-(C,N)-CH _2Si(CH_3)_2N(SiMe_3)] (5) with Et _3N·3HF in toluene gives the uranium(iv) amide-fluoride complex (C_5Me_5)_2U[N(SiMe_3)_2](F) (6). The fluoride complex (C_5Me_5)_2UF _2(NC_5H_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.