title: The U=C double bond: synthesis and study of uranium nucleophilic carbene complexes.
abstract: Treatment of U(BH(4))(4) with 1 or 3 equiv of Li(2)(SCS) x 1.5 Et(2)O, 1, afforded the actinide carbene complexes U(mu-SCS)(3)[U(BH(4))(3)](2) (4) and U(mu-SCS)(3)[Li(Et(2)O)](2) (6), respectively [SCS = (Ph(2)P = S)(2)C]. In THF, complex 4 was transformed into the mononuclear derivative (SCS)U(BH(4))(2)(THF)(2) (5). The multiple bond character of the uranium-carbon bond was first revealed by the X-ray crystal structures of the three complexes. The U=C bond in these complexes present a nucleophilic character, as shown by their reaction with a carbonyl derivative. Finally, DFT calculations prove the involvement of both 5f and 6d orbitals in both the sigma and the pi U-C bonds.
authors.affiliation: Laboratoire Heteroelements et Coordination, CNRS UMR 7653, Ecole Polytechnique, 91128, Palaiseau Cedex, France.
authors.forename: Thibault
authors.initials: T
authors.lastname: Cantat
authors.forename: Thérèse
authors.initials: T
authors.lastname: Arliguie
authors.forename: Anne
authors.initials: A
authors.lastname: Noël
authors.forename: Pierre
authors.initials: P
authors.lastname: Thuéry
authors.forename: Michel
authors.initials: M
authors.lastname: Ephritikhine
authors.forename: Pascal
authors.initials: P
authors.lastname: Le Floch
authors.forename: Nicolas
authors.initials: N
authors.lastname: Mézailles