title: Influence of the substitution and conformation of C--H-bond-based bis-triazole acceptors in anion-binding catalysis.
abstract: A study on the key parameters involved in the anion-binding process and catalytic activity of the new family of CH-bond-based, anion-binding bis-triazole catalysts BisTri was carried out. The effects of substitution at the side arms and the central backbone structure of the catalyst were investigated. Electron-deficient 3,5-bis(trifluoromethyl)phenyl groups at the side arms led to the most strongly bound structures. The evaluation of differently shaped anions showed remarkable binding selectivity of the BisTri derivatives for the chloride anion. Examination of various nucleophiles in a model catalytic alkylation reaction suggested a more complex mechanism than the expected SN 1, in which the nucleophiles also participate partially in activation of the electrophile. DFT calculations were performed to investigate the relationship between the catalyst conformation and the binding affinity. Finally, in silico design and identification of a new, more efficient BisTri catalyst was accomplished.
authors: Organisch-Chemisches Institut, Münster University, Corrensstrasse 40, 48149 Münster (Germany); New address: Institute for Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg (Germany).
authors: Sören
authors: S
authors: Asmus
authors: Stephan
authors: S
authors: Beckendorf
authors: Mercedes
authors: M
authors: Zurro
authors: Christian
authors: C
authors: Mück-Lichtenfeld
authors: Roland
authors: R
authors: Fröhlich
authors: Olga
authors: O
authors: García Mancheño
keywords: alkylation; anion acceptors; anions; nitrogen heterocycles; organocatalysis