Energetics of the O–H Bond in Phenol and Substituted Phenols: A Critical Evaluation of Literature Data

Abstract

This review presents a critical assessment of the available experimental information ͑contained in ϳ90 literature references͒ on the thermochemistry of the O-H bond in phenol and substituted phenols. The analysis led to a set of recommended values for the O-H bond dissociation enthalpies, which in turn allowed us to discuss several empirical and theoretical methodologies used to estimate these data.

Theoretical study of a series of phenol derivatives: molecular properties vs. cytotoxicity

“…3). The latter one seems to be generally difficult to characterize (Borges dos Santos, 1998;Selassie et al, 2002). The reference C1-C2 distance in phenol is 1.39476 Å and Tab.…”

The Vitamin E Radical Probed by Anion Photoelectron Imaging

“…6 The relative efficiencies of x-TocH in vitro appear similar, 8 while in vivo the increased antioxidant potency of α-TocH is due to preferential absorption by the liver. 6 A number of previous studies have presented estimates for the OH bond dissociation enthalpy (BDE) of the tocopherol family of molecules, [36][37][38][39][40][41] which is directly linked to their antioxidant activity. Phenol has a higher BDE than any of the tocopherols, differing by +0.42 eV compared to the most active α-TocH, 37 and a reduced BDE of the OH has been used as the primary criterion in the search for more active antioxidants than the naturally abundant α-TocH.…”

“…6 A number of previous studies have presented estimates for the OH bond dissociation enthalpy (BDE) of the tocopherol family of molecules, [36][37][38][39][40][41] which is directly linked to their antioxidant activity. Phenol has a higher BDE than any of the tocopherols, differing by +0.42 eV compared to the most active α-TocH, 37 and a reduced BDE of the OH has been used as the primary criterion in the search for more active antioxidants than the naturally abundant α-TocH. 42,43 Our experiments have determined the ADE of x-Toc -, which is equivalent to the adiabatic electron affinity of x-Toc  , and can be used to provide a determination of the OH BDE by invoking a thermodynamic cycle proposed by Blanksby and Ellison.…”

An Accurate QSPR Study of O−H Bond Dissociation Energy in Substituted Phenols Based on Support Vector Machines

“…3 Consequently, much effort has been put into understanding the factors governing the O-H bond dissociation energies, O-H BDE, both in the solution and the gas phase. [4][5][6] There are many experimental studies for the determination of the O-H BDE of substituted phenols. [4][5][6] These studies were generally carried out in solutions (such as water, DMSO, etc.…”

“…[4][5][6] There are many experimental studies for the determination of the O-H BDE of substituted phenols. [4][5][6] These studies were generally carried out in solutions (such as water, DMSO, etc. ), and subsequently gas-phase O-H BDE values were determined under some assumptions.…”