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Quantitative model for rationalizing solvent effect in noncovalent CH-Aryl interactions.

ABSTRACT: The strength of CH-aryl interactions (ΔG) in 14 solvents was determined via the conformational analysis of a molecular torsion balance. The molecular balance adopted folded and unfolded conformers in which the ratio of the conformers in solution provided a quantitative measure of ΔG as a function of solvation. While a single empirical solvent parameter based on solvent polarity failed to explain solvent effect in the molecular balance, it is shown that these ΔG values can be correlated through a multiparameter linear solvation energy relationship (LSER) using the equation introduced by Kamlet and Taft. The resulting LSER equation [ΔG = -0.24 + 0.23α - 0.68β - 0.1π* + 0.09δ]-expresses ΔG as a function of Kamlet-Taft solvent parameters-revealed that specific solvent effects (α and β) are mainly responsible for "tipping" the molecular balance in favour of one conformer over the other, where α represents a solvents' hydrogen-bond acidity and β represents a solvents' hydrogen-bond basicity. Furthermore, using extrapolated data (α and β) and the known π* value for the gas phase, the LSER equation predicted ΔG in the gas phase to be -0.31 kcal mol^-1, which agrees with -0.35 kcal mol^-1 estimated from DFT-D calculations.

SUBMITTER: Emenike BU

PROVIDER: S-EPMC5975927 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Quantitative model for rationalizing solvent effect in noncovalent CH-Aryl interactions.

Emenike Bright U BU Bey Sara N SN Bigelow Brianna C BC Chakravartula Srinivas V S SVS

Chemical science 20151117 2

The strength of CH-aryl interactions (ΔG) in 14 solvents was determined via the conformational analysis of a molecular torsion balance. The molecular balance adopted folded and unfolded conformers in which the ratio of the conformers in solution provided a quantitative measure of ΔG as a function of solvation. While a single empirical solvent parameter based on solvent polarity failed to explain solvent effect in the molecular balance, it is shown that these ΔG values ...[more]

PMID: 29910898

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Dataset Information

Quantitative model for rationalizing solvent effect in noncovalent CH-Aryl interactions.

Publications

Quantitative model for rationalizing solvent effect in noncovalent CH-Aryl interactions.

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