title: Systematic investigation of thorium(IV)- and uranium(IV)-ligand bonding in dithiophosphonate, thioselenophosphinate, and diselenophosphonate complexes.
abstract: Homoleptic soft-donor actinide complexes of the general form An[E2PROR']4 were synthesized from salt metathesis between ThCl4(DME)2 or UI4(1,4-dioxane)2 and M[E2PROR'], M = Na, K, to yield 2 (An = Th, E = S, R = 4-MeOC6H4, R' = Me), 3 (An = Th, E = S, R = 4-MeOC6H4, R' = (t)Bu), 4 (An = U, E = S, R = 4-MeOC6H4, R' = Me), 5 (An = Th, E = Se, R = C6H5, R' = Me), and 6 (An = U, E = Se, R = C6H5, R' = Me). In addition thorium and uranium thioselenophosphinate complexes 7 and 8 were produced from the reaction of ThCl4(DME)2 and UI4(1,4-dioxane)2 and Na[SSePPh2], respectively. All compounds were characterized using elemental analysis, (1)H and (31)P NMR, and IR spectroscopy, and the U(IV) compounds were also examined with UV-vis spectroscopy. The (77)Se NMR spectrum of 5 reveals the first reported resonance with a Th-Se bond. The solid-state structures of 2, 5, 7, and 8 were determined by X-ray crystallography. The actinide-ligand bonding was examined using density functional theory calculations in conjunction with quantum theory of atoms-in-molecules analysis and shows slightly increased covalency in actinide-selenium bonds than actinide-sulfur.
authors.affiliation: Department of Chemistry, University of Missouri-Columbia , 601 S. College Avenue, Columbia, Missouri 65211-7600, United States.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Behrle
authors.forename: Charles L
authors.initials: CL
authors.lastname: Barnes
authors.forename: Nikolas
authors.initials: N
authors.lastname: Kaltsoyannis
authors.forename: Justin R
authors.initials: JR
authors.lastname: Walensky