Conversion of Trivalent Uranium Anilido to Tetravalent Uranium Imido Species via Oxidative Deprotonation

Two uranium­(III) anilido complexes were synthesized, Tp*₂U­(NH-C₆H₄-p-terpyridine) (2-terpy) and Tp*₂U­(NH-C₆H₄-p-CH₃) (2-ptol), where Tp* = hydrotris­(3,5-dimethylpyrazolyl)­borate, by protonation of Tp*₂UBn (1-Bn; Bn = benzyl) with 4-[2,6-di­(pyridin-2-yl)­pyridin-4-yl]­benzenamine or p-toluidine, respectively. Conversion to the respective uranium­(IV) imido species was possible by oxidation and deprotonation, forming Tp*₂U­(N-C₆H₄-p-terpyridine) (3-terpy) and Tp*₂U­(N-C₆H₄-p-CH₃) (3-ptol). These compounds were characterized by multinuclear NMR spectroscopy, IR spectroscopy, electronic absorption spectroscopy, and X-ray crystallography.