title: Intrinsic reactivity of a uranium metallacyclopropene toward unsaturated organic molecules.
abstract: The uranium metallacyclopropene (η5-C5Me5)2U[η2-C2(SiMe3)2] (1) reacts with various small unsaturated organic molecules. For example, replacement of bis(trimethylsilyl)acetylene occurs when complex 1 is exposed to alkynes, conjugated alkenes, nitriles and quinones. Reaction of 1 with internal phenyl(alkyl)acetylene PhC[triple bond, length as m-dash]CMe selectively yields the Cssymmetric uranium metallacyclopentadiene (η5-C5Me5)2U[η2-C(Ph)[double bond, length as m-dash]C(Me)-C(Ph)[double bond, length as m-dash]C(Me)] (6) after the loss of bis(trimethylsilyl)acetylene, while treatment of 1 with phenyl(silyl)acetylenes (PhC[triple bond, length as m-dash]CR, R = SiHMe2, SiMe3) gives the corresponding C2vsymmetric isomers (η5-C5Me5)2U[η2-C(R)[double bond, length as m-dash]C(Ph)-C(Ph)[double bond, length as m-dash]C(R)] (R = SiHMe2(7), SiMe3(8)). Furthermore, while no deprotonation occurs between complex 1 and pyridine derivatives, cyclohexanone can be inserted into the uranium metallacyclopropene moiety of 1 to yield the five-membered, heterocyclic complex (η5-C5Me5)2U[OC(CH2)5(C2(SiMe3)2)] (14) in quantitative conversion. Density functional theory (DFT) studies have been performed to complement the experimental studies.
authors.affiliation: Department of Chemistry, Beijing Normal University, Beijing 100875, China. dingwanjian@bnu.edu.cn gzi@bnu.edu.cn.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, Beijing Normal University, Beijing 100875, China. dingwanjian@bnu.edu.cn gzi@bnu.edu.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Fang
authors.affiliation: Department of Chemistry, Beijing Normal University, Beijing 100875, China. dingwanjian@bnu.edu.cn gzi@bnu.edu.cn.
authors.forename: Guohua
authors.initials: G
authors.lastname: Hou
authors.affiliation: Department of Chemistry, Beijing Normal University, Beijing 100875, China. dingwanjian@bnu.edu.cn gzi@bnu.edu.cn.
authors.forename: Lin
authors.initials: L
authors.lastname: Ai
authors.affiliation: Department of Chemistry, Beijing Normal University, Beijing 100875, China. dingwanjian@bnu.edu.cn gzi@bnu.edu.cn.
authors.forename: Wanjian
authors.initials: W
authors.lastname: Ding
authors.affiliation: Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany. mwalter@tu-bs.de.
authors.forename: Marc D
authors.initials: MD
authors.lastname: Walter
authors.affiliation: Department of Chemistry, Beijing Normal University, Beijing 100875, China. dingwanjian@bnu.edu.cn gzi@bnu.edu.cn.
authors.forename: Guofu
authors.initials: G
authors.lastname: Zi