Oxo ligand silylation in a uranyl beta-ketoiminate complex

Area of Science:

• Organometallic Chemistry
• Uranium Chemistry
• Silicon Chemistry

Background:

• Uranyl complexes with bulky beta-diketiminate ligands, (Ar)acnac, are investigated for their reactivity.
• The role of silylating agents in modifying uranium coordination environments is a key area of interest.

Purpose of the Study:

• To explore the reaction of uranyl complexes with trimethylsilyl iodide (Me3SiI).
• To compare the reactivity of Me3SiI with other trimethylsilyl halides (Me3SiX, where X = Cl, OTf) towards uranyl complexes.

Main Methods:

• Reaction of uranyl complex UO2((Ar)acnac)2 with Me3SiI.
• Isolation and characterization of reaction products.
• Comparative study with reactions involving Me3SiCl and Me3SiOTf.

Main Results:

• Addition of Me3SiI to UO2((Ar)acnac)2 yields U(OSiMe3)2I2((Ar)acnac) in moderate yield.
• Side products include I2 and a silylated ligand, ArNC(Ph)=CHC(Ph)OSiMe3, resulting from Me3Si+ abstraction.
• Reactions with Me3SiCl and Me3SiOTf produce different uranyl complexes, UO2Cl2((Ar)acnacH)2 and UO2(OTf)2((Ar)acnacH)2(Et2O), respectively.

Conclusions:

• Me3SiI exhibits distinct reactivity compared to Me3SiCl and Me3SiOTf with uranyl complexes.
• The reaction pathway with Me3SiI involves silylation of the uranyl oxygen and ligand abstraction.
• The choice of trimethylsilyl halide significantly influences the outcome of reactions with uranyl beta-diketiminate complexes.