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Updated: Sep 3, 2025

Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Insights on the Lewis Superacid Al(OTeF5 )3 : Solvent Adducts, Characterization and Properties
Kurt F Hoffmann1, Anja Wiesner1, Simon Steinhauer1
1Fachbereich für Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie - Anorganische Chemie, Fabeckstraße 34/36, 14195, Berlin, Germany.
Abstract:
Preparation and characterization of the dimeric Lewis superacid [Al(OTeF5 )3 ]2 and various solvent adducts is presented. The latter range from thermally stable adducts to highly reactive, weakly bound species. DFT calculations on the ligand affinity of these Lewis acids were performed in order to rank their remaining Lewis acidity. An experimental proof of the Lewis acidity is provided by the reaction of solvent-adducts of Al(OTeF5 )3 with [PPh4 ][SbF6 ] and OPEt3 , respectively. Furthermore, their reactivity towards chloride and pentafluoroorthotellurate salts as well as (CH3 )3 SiCl and (CH3 )3 SiF is shown. This includes the formation of the dianion [Al(OTeF5 )5 ]2- .
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