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Updated: Jun 22, 2025

Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Host-guest chemistry of tridentate Lewis acids based on tribenzotriquinacene
Maurice Franke1, Tobin Ens1, Andreas Mix1
1Universität Bielefeld, Fakultät für Chemie, Lehrstuhl für Anorganische Chemie und Strukturchemie (ACS), Centre for Molecular Materials (CM2), Universitätsstraße 25, D-33615 Bielefeld, Germany. mitzel@uni-bielefeld.de.
Abstract:
Flexible poly-Lewis acids (PLA) based on the tribenzotriquinacene (TBTQ) scaffold have been synthesised. Hydrosilylation of 4b,8b,12b-triallyltribenzotriquinacene and subsequent exchange of the chlorine substituents with weaker coordinating triflate groups afforded a novel triple silyl-functionalised PLA. By regioselective hydroboration of triallyl-TBTQ with various organoboranes, PLAs with different Lewis acidities were obtained. The synthesised PLAs were combined with neutral bases in host-guest experiments. DOSY NMR spectroscopy was performed to elucidate the complexation process in solution. These experiments revealed a highly dynamic interaction between the boron-functionalised PLA and triazine. However, the addition of one equivalent of tris(dimethylphosphino(methyl))phenylsilane led to the formation of a 1 : 1 adduct, which was confirmed by diffusion experiments.
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