Imido Exchange in Bis(imido) Uranium(Ⅵ) Complexes with Aryl Isocyanates

摘要

For the past 150 years, studies of uranium(Ⅵ) have been generally directed toward understanding the chemical behavior and unique bonding in the uranyl ion (UO_2~(2+)). This ion possesses U-O bonds which have high thermodynamic stability and extreme kinetic inertness. As a result, the majority of UO_2~(2+) reaction chemistry involves substitution of equatorially coordinated ligands while leaving the U-O bond unaffected. Recently, we have reported the syntheses of isoelectronic bis(imido) [U(NR)_2]~(2+) and oxo-imido [U(NR)(O)]~(2+) ions which possess many of the bonding features found in UO_2~(2+). Our recent isolation of these ions has stimulated us to investigate their reactivity to elucidate a more complete understanding of uranium(Ⅵ) chemistry.