title: Trivalent uranium phenylchalcogenide complexes: exploring the bonding and reactivity with CS2 in the Tp*2UEPh series (E = O, S, Se, Te).
abstract: The trivalent uranium phenylchalcogenide series, Tp*2UEPh (Tp* = hydrotris(3,5-dimethylpyrazolyl)borate, E = O (1), S (2), Se (3), Te (4)), has been synthesized to investigate the nature of the U-E bond. All compounds have been characterized by (1)H NMR, infrared and electronic absorption spectroscopies, and in the case of 4, X-ray crystallography. Compound 4 was also studied by SQUID magnetometry. Computational studies establish Mulliken spin densities for the uranium centers ranging from 3.005 to 3.027 (B3LYP), consistent for uranium-chalcogenide bonds that are primarily ionic in nature, with a small covalent contribution. The reactivity of 2-4 toward carbon disulfide was also investigated and showed reversible CS2 insertion into the U(III)-E bond, forming Tp*2U(κ(2)-S2CEPh) (E = S (5), Se (6), Te (7)). Compound 5 was characterized crystallographically.
authors.affiliation: H.C. Brown Laboratory, Department of Chemistry, Purdue University , West Lafayette 47907, Indiana, United States.
authors.forename: Ellen M
authors.initials: EM
authors.lastname: Matson
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Breshears
authors.forename: John J
authors.initials: JJ
authors.lastname: Kiernicki
authors.forename: Brian S
authors.initials: BS
authors.lastname: Newell
authors.forename: Phillip E
authors.initials: PE
authors.lastname: Fanwick
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Shores
authors.forename: Justin R
authors.initials: JR
authors.lastname: Walensky
authors.forename: Suzanne C
authors.initials: SC
authors.lastname: Bart