Publication | Open Access
Reduction of Carbonyl Groups by Uranium(III) and Formation of a Stable Amide Radical Anion
34
Citations
76
References
2017
Year
Methyl benzoate, N,N-dimethylbenzamide, and benzophenone were reduced by U<sup>III</sup> [N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> resulting in uranium(IV) products. Reduction of benzophenone lead to U<sup>IV</sup> [OC⋅Ph<sub>2</sub> )][N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> , (1.1) which forms the dinuclear complex, [N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> U<sup>IV</sup> (OCPhPh-CPh<sub>2</sub> O)U<sup>IV</sup> [N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> (1.2), through coupling of the ketyl radical species upon crystallization. Reaction of N,N-dimethylbenzamide with U<sup>III</sup> [N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> resulted in U<sup>IV</sup> [OC⋅(Ph)(NMe<sub>2</sub> )][N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> (2), a uranium(IV) compound and the first example of a charge-separated amide radical. In the case of methyl benzoate, the reduction resulted in U<sup>IV</sup> (OMe)[N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> (3) and benzaldehyde as the reduced organic fragment. Compound 2 showed the ability to act as a uranium(III) synthon in its reactivity with trimethylsilyl azide, a reaction that yielded U<sup>V</sup> (=NSiMe<sub>3</sub> )[N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> . Additionally, 2 was reduced with potassium graphite resulting in [U(μ-O)[O=C(NMe<sub>2</sub> )(Ph)][N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>2</sub> ]<sub>2</sub> (4), a dinuclear uranium compound bridged by oxo ligands. Reduction of 2 in the presence of 15-crown-5 afforded isolation of the mono-oxo compound, [(15-crown-5)<sub>2</sub> K][UO[N(SiMe<sub>3</sub> )<sub>2</sub> ]<sub>3</sub> ] (5). The results expand the reduction capabilities of U<sup>III</sup> complexes and demonstrate a strategy for isolating novel metal-stabilized radicals.
| Year | Citations | |
|---|---|---|
Page 1
Page 1