Towards high-valent uranium compounds from metallacyclic uranium(iv) precursors

Abstract

Treatment of [NaUN*(C,N)₂] [N* = N(SiMe₃)₂; C,N = CH₂SiMe₂N(SiMe₃)] with I₂ led to the formation of the larger metallacycle [UN*(N{SiMe₃}SiMe₂CH₂CH₂SiMe₂N{SiMe₃})I] resulting from U–C cleavage and C–C coupling. Reaction of [NaUN*(O,N)₂] [O,N = OC(CH₂)SiMe₂N(SiMe₃)] with I₂ afforded the U^V complex [Na{UN*(O,N)₂}₂(μ-I)] which was converted into the mononuclear azido derivative [NaUN*(O,N)₂(N₃)]. This latter was not transformed into the neutral U^VI derivative in the presence of I₂ but afforded [U^V(N{SiMe₃}SiMe₂C{CHI}O)₂I(THF)], resulting from a cascade of addition, substitution and protonolysis reactions.