Exploration of the Interconversion of Uranium Anilido and Imido Species

Exploring the reactivity of the trivalent uranium penta(anilido) species, U(NHDIPP) 5 K 2 (THF) 4 ( 1 ) (DIPP = 2,6‐diisopropylphenyl), leads to the formation of uranium imido complexes. Treating 1 with 2 equivalents (equiv) of 18‐crown‐6 (18c6) causes spontaneous oxidation and the formation of [U(NDIPP)(NHDIPP) 4 ][K(18c6)(THF)] 2 ( 2 ). Oxidation of 1 with AgBPh 4 , or 2 with I 2, results in the formation of the uranium(VI) bis(anilido) bis(imido) compound, U(NDIPP) 2 (NHDIPP) 2 ( 3 ). This species is in equilibrium with the previously established U(NDIPP) 3 and is trapped with one equiv of of 2,2′‐bipyridine (bpy) to form (bpy)U(NDIPP) 2 (NHDIPP) 2 ( 4 ). All species are analyzed by 1 H NMR spectroscopy and X‐ray crystallography, where possible.