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Updated: Apr 19, 2026
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Cationic zinc organyls as precatalysts for hydroamination reactions
Maren A Chilleck1, Larissa Hartenstein, Thomas Braun
1Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin (Germany).
Abstract:
The cationic zinc triple-decker complex [Zn2 Cp*3 ](+) [BAr(F) 4 ](-) (BAr(F) 4 =B(3,5-(CF3 )2 C6 H3 )4 ) exhibits catalytic activity in intra- and intermolecular hydroamination reactions in the absence of a cocatalyst. These hydroaminations presumably proceed through the activation of the C-C multiple bond of the alkene or alkyne by a highly electrophilic zinc species, which is formed upon elimination of the Cp* ligands. The reaction of [Zn2 Cp*3 ](+) [BAr(F) 4 ](-) with henylacetylene gives the hydrocarbonation product (Cp*)(Ph)CCH2 , which might be formed via a similar reaction pathway. Additionally, several other structurally well-defined cationic zinc organyls have been examined as precatalysts for intermolecular hydroamination reactions without the addition of a cocatalyst. These studies reveal that the highest activity is achieved in the absence of any donor ligands. The neutral complex [ZnCp(2S) 2 ] (Cp(2S) =C5 Me4 (CH2 )2 SMe) shows a remarkably high catalytic activity in the presence of a Brønsted acid.
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