skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Preparation, solution behavior, and solid-state structures of (1,3-R{sub 2}C{sub 5}H{sub 3}){sub 2}UX{sub 2}, where R is CMe{sub 3} or SiMe{sub 3} and X is a one-electron ligand

Abstract

High-yield preparations of the uranium metallocenes [1,3-(Me{sub 3}Si){sub 2}C{sub 5}H{sub 3}]{sub 2}UCL{sub 2}(Cp{double_prime}{sub 2}UCL{sub 2}) and [1,3-(Me{sub 3}C){sub 2}C{sub 5}H{sub 3}]{sub 2}UCL{sub 2} (Cp{sup {double_dagger}}{sub 2}UCL{sub 2}) have been developed from the reaction of UCl{sub 4} and the corresponding magnesocenes Cp{double_prime}{sub 2}Mg and Cp{sup {double_dagger}}{sub 2}Mg in diethyl ether. The chloride ligands can be exchanged with either Me{sub 3}SiBr or Me{sub 3}SiI to give the uranium metallocene bromides or iodides. The fluorides were prepared by the reaction of BF{sub 3}{center_dot}OEt{sub 2} with Cp{double_prime}{sub 2}U(NMe){sub 2}, Cp{sup {double_dagger}}{sub 2}U(OMe){sub 2}, or Cp{sup {double_dagger}}{sub 2}UMe{sub 2}. The crystal structures of Cp{double_prime}{sub 2}UCl{sub 2}, Cp{sup {double_dagger}}{sub 2}UCl{sub 2}, Cp{double_prime}{sub 2}UMe{sub 2}, Cp{sup {double_dagger}}{sub 2}UF{sub 2}, and dimeric (Cp{double_prime}{sub 2}UF{sub 2}){sub 2} are reported. The idealized symmetry of the monomers Cp{double_prime}{sub 2}UX{sub 2} and Cp{sup {double_dagger}}{sub 2}UCl{sub 2} is C{sub 2{nu}} when X is F, Cl, or Br and C{sub 2} when X is I or Me; in the dimer, the idealized symmetry is C{sub i}. This preference is rationalized by intramolecular and intermolecular steric effects. The solution ring conformations and intramolecular exchange processes have been studied by variable-temperature {sup 1}H NMR spectroscopy. In all cases, the low-temperature limiting spectra are consistent with themore » idealized symmetry observed in the solid state.« less

Authors:
; ; ; ;  [1]
  1. Lawrence Berkeley Lab., CA (United States)
Publication Date:
Sponsoring Org.:
National Science Foundation, Washington, DC (United States); USDOE, Washington, DC (United States)
OSTI Identifier:
343700
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Journal Article
Journal Name:
Organometallics
Additional Journal Information:
Journal Volume: 18; Journal Issue: 7; Other Information: PBD: 29 Mar 1999
Country of Publication:
United States
Language:
English
Subject:
40 CHEMISTRY; URANIUM COMPOUNDS; CHEMICAL PREPARATION; ORGANOMETALLIC COMPOUNDS; CRYSTAL STRUCTURE; HALIDES; PHYSICAL PROPERTIES

Citation Formats

Lukens, Jr, W W, Beshouri, S M, Blosch, L L, Stuart, A L, and Andersen, R A. Preparation, solution behavior, and solid-state structures of (1,3-R{sub 2}C{sub 5}H{sub 3}){sub 2}UX{sub 2}, where R is CMe{sub 3} or SiMe{sub 3} and X is a one-electron ligand. United States: N. p., 1999. Web. doi:10.1021/om9805988.
Lukens, Jr, W W, Beshouri, S M, Blosch, L L, Stuart, A L, & Andersen, R A. Preparation, solution behavior, and solid-state structures of (1,3-R{sub 2}C{sub 5}H{sub 3}){sub 2}UX{sub 2}, where R is CMe{sub 3} or SiMe{sub 3} and X is a one-electron ligand. United States. https://doi.org/10.1021/om9805988
Lukens, Jr, W W, Beshouri, S M, Blosch, L L, Stuart, A L, and Andersen, R A. Mon . "Preparation, solution behavior, and solid-state structures of (1,3-R{sub 2}C{sub 5}H{sub 3}){sub 2}UX{sub 2}, where R is CMe{sub 3} or SiMe{sub 3} and X is a one-electron ligand". United States. https://doi.org/10.1021/om9805988.
@article{osti_343700,
title = {Preparation, solution behavior, and solid-state structures of (1,3-R{sub 2}C{sub 5}H{sub 3}){sub 2}UX{sub 2}, where R is CMe{sub 3} or SiMe{sub 3} and X is a one-electron ligand},
author = {Lukens, Jr, W W and Beshouri, S M and Blosch, L L and Stuart, A L and Andersen, R A},
abstractNote = {High-yield preparations of the uranium metallocenes [1,3-(Me{sub 3}Si){sub 2}C{sub 5}H{sub 3}]{sub 2}UCL{sub 2}(Cp{double_prime}{sub 2}UCL{sub 2}) and [1,3-(Me{sub 3}C){sub 2}C{sub 5}H{sub 3}]{sub 2}UCL{sub 2} (Cp{sup {double_dagger}}{sub 2}UCL{sub 2}) have been developed from the reaction of UCl{sub 4} and the corresponding magnesocenes Cp{double_prime}{sub 2}Mg and Cp{sup {double_dagger}}{sub 2}Mg in diethyl ether. The chloride ligands can be exchanged with either Me{sub 3}SiBr or Me{sub 3}SiI to give the uranium metallocene bromides or iodides. The fluorides were prepared by the reaction of BF{sub 3}{center_dot}OEt{sub 2} with Cp{double_prime}{sub 2}U(NMe){sub 2}, Cp{sup {double_dagger}}{sub 2}U(OMe){sub 2}, or Cp{sup {double_dagger}}{sub 2}UMe{sub 2}. The crystal structures of Cp{double_prime}{sub 2}UCl{sub 2}, Cp{sup {double_dagger}}{sub 2}UCl{sub 2}, Cp{double_prime}{sub 2}UMe{sub 2}, Cp{sup {double_dagger}}{sub 2}UF{sub 2}, and dimeric (Cp{double_prime}{sub 2}UF{sub 2}){sub 2} are reported. The idealized symmetry of the monomers Cp{double_prime}{sub 2}UX{sub 2} and Cp{sup {double_dagger}}{sub 2}UCl{sub 2} is C{sub 2{nu}} when X is F, Cl, or Br and C{sub 2} when X is I or Me; in the dimer, the idealized symmetry is C{sub i}. This preference is rationalized by intramolecular and intermolecular steric effects. The solution ring conformations and intramolecular exchange processes have been studied by variable-temperature {sup 1}H NMR spectroscopy. In all cases, the low-temperature limiting spectra are consistent with the idealized symmetry observed in the solid state.},
doi = {10.1021/om9805988},
url = {https://www.osti.gov/biblio/343700}, journal = {Organometallics},
number = 7,
volume = 18,
place = {United States},
year = {1999},
month = {3}
}