Correlations and Predictions of Carboxylic Acid pKa Values Using Intermolecular Structure and Properties of Hydrogen-Bonded Complexes
- 1 January 2008
- journal article
- research article
- Published by American Chemical Society (ACS) in The Journal of Physical Chemistry A
- Vol. 112 (4), 775-782
- https://doi.org/10.1021/jp710291c
Abstract
Density functional theory calculations have been preformed on a series of hydrogen-bonded complexes of substituted aliphatic and aromatic carboxylic acids with ammonia. Molecular properties, particularly those related to hydrogen bonding, have been carefully examined for their interdependence as well as dependence on the acidity of the acid. The bond length and stretching frequency of the hydroxyl group and the hydrogen-bond length and energy of the complex are shown to be highly correlated with each other and are linearly correlated with available literature pKa values of the carboxylic acids. The linear correlations resulting from the fit to the available pKa values can be used to predict the pKa values of similar carboxylic acids. The pKa values so predicted using the different molecular properties are highly consistent and in good agreement with the literature values. This study suggests that calculated molecular properties of hydrogen-bonded complexes allow effective and systematic prediction of pKa values for a large range of organic acids using the established linear correlations. This approach is unique in its capability to determine the acidity of a particular functional group or the local acidity within a large molecular system such as a protein.Keywords
This publication has 16 references indexed in Scilit:
- Accurate Prediction of Absolute Acidity Constants in Water with a Polarizable Force Field: Substituted Phenols, Methanol, and ImidazoleThe Journal of Physical Chemistry B, 2005
- High thermal-stable sol–gel-coated calix[4]arene fiber for solid-phase microextraction of chlorophenolsAnalytica Chimica Acta, 2004
- Accurate Prediction of Acidity Constants in Aqueous Solution via Density Functional Theory and Self-Consistent Reaction Field MethodsThe Journal of Physical Chemistry A, 2002
- Density Functional Study on Phenol Derivative−Ammonia Complexes in the Gas PhaseThe Journal of Physical Chemistry A, 2000
- Ab Initio Calculations of Absolute pKaValues in Aqueous Solution I. Carboxylic AcidsThe Journal of Physical Chemistry A, 1999
- Ionic dissociation of hydrogen bromide in water clusters: a computational studyChemical Physics Letters, 1999
- Ring Strain and Hydrogen Bond AcidityThe Journal of Organic Chemistry, 1998
- Proton transfer from 1-naphthol to water: Small clusters to the bulkThe Journal of Chemical Physics, 1989
- Evidence from Fourier transform infrared spectroscopy for polarization of the carbonyl of oxaloacetate in the active site of citrate synthaseBiochemistry, 1987
- Structure and specific binding of trypsin: Comparison of inhibited derivatives and a model for substrate bindingJournal of Molecular Biology, 1974