title: An actinide metallacyclopropene complex: synthesis, structure, reactivity, and computational studies.
abstract: The synthesis, structure, and reactivity of an actinide metallacyclopropene were comprehensively studied. The reduction of [η(5)-1,2,4-(Me3C)3C5H2]2ThCl2 (1) with potassium graphite (KC8) in the presence of diphenylacetylene (PhC≡CPh) yields the first stable actinide metallacyclopropene [η(5)-1,2,4-(Me3C)3C5H2]2Th(η(2)-C2Ph2) (2). The magnetic susceptibility data show that 2 is indeed a diamagnetic Th(IV) complex, and density functional theory (DFT) studies suggest that the 5f orbitals contribute to the bonding of the metallacyclopropene Th-(η(2)-C═C) moiety. Complex 2 shows no reactivity toward alkynes, but it reacts with a variety of heterounsaturated molecules such as aldehyde, ketone, carbodiimide, nitrile, organic azide, and diazoalkane derivatives. DFT studies complement the experimental observations and provide additional insights. Furthermore, a comparison between Th and group 4 metals reveals that Th(4+) shows unique reactivity patterns.
authors.affiliation: Department of Chemistry, Beijing Normal University , Beijing 100875, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Fang
authors.forename: Wenshan
authors.initials: W
authors.lastname: Ren
authors.forename: Guohua
authors.initials: G
authors.lastname: Hou
authors.forename: Guofu
authors.initials: G
authors.lastname: Zi
authors.forename: De-Cai
authors.initials: DC
authors.lastname: Fang
authors.forename: Laurent
authors.initials: L
authors.lastname: Maron
authors.forename: Marc D
authors.initials: MD
authors.lastname: Walter