title: A general and modular synthesis of monoimidouranium(IV) dihalides.
abstract: The conproportionation reaction between the dimeric diimidouranium(V) species [U(N(t)Bu)(2)(I)((t)Bu(2)bpy)](2) ((t)Bu(2)bpy = 4,4'-di-tert-butyl-2,2'-bipyridyl) and UI(3)(THF)(4) in the presence of additional (t)Bu(2)bpy yields U(N(t)Bu)(I)(2)((t)Bu(2)bpy)(THF)(2) (2), an unprecedented example of a monoimidouranium(IV) dihalide complex. The general synthesis of this family of uranium(IV) derivatives can be achieved more readily by adding 2 equiv of MN(H)R (M = Li, K; R = (t)Bu, 2,6-(i)PrC(6)H(3), 2-(t)BuC(6)H(4)) to UX(4) in the presence of coordinating Lewis bases to give complexes with the general formula U(NR)(X)(2)(L)(n) (X = Cl, I; L = (t)Bu(2)bpy, n = 1; L = THF, n = 2). The complexes were characterized by (1)H NMR spectroscopy and single-crystal X-ray diffraction analysis of compounds 2 and {U[N(2,6-(i)PrC(6)H(3))](Cl)(2)(THF)(2)}(2) (4). (The X-ray structures of 5 and 6 are reported in the Supporting Information.)
authors.affiliation: MPA Division, Los Alamos National Laboratory, MS J514, Los Alamos, New Mexico 87545, USA.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Jilek
authors.forename: Liam P
authors.initials: LP
authors.lastname: Spencer
authors.forename: David L
authors.initials: DL
authors.lastname: Kuiper
authors.forename: Brian L
authors.initials: BL
authors.lastname: Scott
authors.forename: Ursula J
authors.initials: UJ
authors.lastname: Williams
authors.forename: James M
authors.initials: JM
authors.lastname: Kikkawa
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Schelter
authors.forename: James M
authors.initials: JM
authors.lastname: Boncella