Theoretical study of the energetics of carboxylic O—H bond cleavage in the para- and meta-substituted benzoic acid derivatives
Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, SK-812 37 Bratislava, Slovakia
a Department of NMR Spectroscopy and Mass Spectroscopy, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, SK-812 37 Bratislava, Slovakia
E-mail: * email@example.com
Abstract: Gas phase bond dissociation enthalpies (BDE) of para- and meta-substituted benzoic acids and proton affinities (PA) of their carboxylate anions were investigated using the B3LYP/6-311++G** method for 15 substituents with various electron-donating and electron-withdrawing effects. The employed computational method provided BDE and PA values in fair agreement with experimental data. The substituent effect on BDEs and PAs was analyzed in terms of Hammett constants. Found dependences exhibit satisfactory linearity and enable quick estimation of BDEs and PAs from the Hammett constants.
Keywords: bond dissociation enthalpy, proton affinity, hydrogen atom transfer (HAT), deprotonation, benzoic acid, phenol
Full paper in Portable Document Format: acs_0211.pdf
Acta Chimica Slovaca, Vol. 8, No. 1, 2015, pp. 70—77, DOI: 10.1515/acs-2015-0013