199800-27-6Relevant academic research and scientific papers
Synthesis and conversions of metallocycles 22. NMR studies of the mechanism of Cp2ZrCl2-catalyzed cycloalumination of olefins with triethylaluminum to form aluminacyclopentanes
Khalilov,Parfenova,Rusakov,Ibragimov,Dzhemilev
, p. 2051 - 2058 (2007/10/03)
The mechanism of cycloalumination of olefins under the action of AlEt3 in the presence of Cp2ZrCl2 giving rise to aluminacyclopentanes was investigated by dynamic 1H and 13C NMR spectroscopy. The bimetallic complex Cp2ZrEtCl-AlEt3 is formed initially and is converted into the bridged complex Cp2Zr(Cl)CH2CH2AlEt2 as a result of β-hydride shift and elimination of the ethane molecule. The resulting complex adds a molecule of the initial olefin yielding aluminacyclopentanes. Under the action of Et2AlCl in the presence of an excess of AlEt3, zirconacyclopentanes give rise to intermediate bimetallic complexes stable at -70 °C. Under the reaction conditions, the latter compounds are converted into aluminacyclopentanes.
