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Stabilization of 2,6-Diarylanilinum Cation by Through-Space Cation-π Interactions
Joan Simó Padial1, Jordi Poater2,3, D Thao Nguyen1
1Institute for Molecules and Materials, Radboud University , Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
Abstract:
Energetically favorable cation-π interactions play important roles in numerous molecular recognition processes in chemistry and biology. Herein, we present synergistic experimental and computational physical-organic chemistry studies on 2,6-diarylanilines that contain flanking meta/para-substituted aromatic rings adjacent to the central anilinium ion. A combination of measurements of pKa values, structural analyses of 2,6-diarylanilinium cations, and quantum chemical analyses based on the quantitative molecular orbital theory and a canonical energy decomposition analysis (EDA) scheme reveal that through-space cation-π interactions essentially contribute to observed trends in proton affinities and pKa values of 2,6-diarylanilines.
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