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Stabilization of 2,6-Diarylanilinum Cation by Through-Space Cation-? Interactions.

ABSTRACT: Energetically favorable cation-? 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-? interactions essentially contribute to observed trends in proton affinities and pKa values of 2,6-diarylanilines.

SUBMITTER: Simo Padial J

PROVIDER: S-EPMC5603827 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Stabilization of 2,6-Diarylanilinum Cation by Through-Space Cation-π Interactions.

Simó Padial Joan J Poater Jordi J Nguyen D Thao DT Tinnemans Paul P Bickelhaupt F Matthias FM Mecinović Jasmin J

The Journal of organic chemistry 20170831 18

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 pK<sub>a</sub> values, structural analyses of 2,6-diarylanilinium cations, and quantum chemical analyses based on ...[more]

PMID: 28836782

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