title: Uranium(VI) sulfilimine complexes: a new class of nitrogen analogues of the uranyl ion.
abstract: The compound tetraphenylphosphonium tetrachlorooxo-S,S-diphenylsulfiliminatouranium, [Ph4P][UOCl4(NSPh2)], has been prepared in high yield from [Ph4P][UOCl5] and [Ph2S=NSiMe3]. An X-ray structure of this compound shows that the uranium atom has a pseudooctahedral geometry with oxygen and nitrogen atoms in trans positions. The structure of the analogous phosphoriminato complex [Ph4P][UOCl4(NPPh3)] has been determined for comparison. Derivatization of the sulfide group shows that only a limited range of functionalization confers stability toward reduction. The emission spectrum of the first electronic excited state reveals a greatly reduced energy compared with that of the uranyl ion. This red shift in the transition is consistent with the weakening of the U-N bond relative to the U-O bond.
authors.affiliation: Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, U.K.
authors.forename: V C
authors.initials: VC
authors.lastname: Williams
authors.forename: M
authors.initials: M
authors.lastname: Müller
authors.forename: M A
authors.initials: MA
authors.lastname: Leech
authors.forename: R G
authors.initials: RG
authors.lastname: Denning
authors.forename: M L
authors.initials: ML
authors.lastname: Green