Bond Strengths of Toluenes, Anilines, and Phenols: To Hammett or Not
Citations Over TimeTop 10% of 2004 papers
Abstract
The Hammett equation correlates the effects of Y on many different chemical properties of YC(6)H(4)ZX families of compounds. One of the most surprising is that the Z-X bond dissociation enthalpy (BDE), a homolytic property, can be correlated for some 4-YC(6)H(4)ZX families with electrophilic substituent constants, sigma(p)(+)(Y), which were largely derived from the rates of the heterolytic S(N)1 solvolyses of para-substituted cumyl chlorides. Although there is no Hammett correlation of the C-X BDEs in 4-YC(6)H(4)CH(2)X (X = H, halide, OPh) families, there are good correlations of N-X BDEs with sigma(p)(+)(Y) in 4-YC(6)H(4)NHX (X = H, CH(3), OH, F) and excellent correlations of O-X BDEs with sigma(p)(+)(Y) in 4-YC(6)H(4)OX (X = H, CH(3), CH(2)Ph) families. The reasons for this varied behavior are discussed.
Related Papers
- → N−NO Bond Dissociation Energies of N-Nitroso Diphenylamine Derivatives (Or Analogues) and Their Radical Anions: Implications for the Effect of Reductive Electron Transfer on N−NO Bond Activation and for the Mechanisms of NO Transfer to Nitranions(2000)63 cited
- → Heterolytic and homolytic C-D bond dissociation energies of NADH models in acetonitrile and primary isotopic effects on hydride versus hydrogen atom transfer reactions(2012)4 cited
- Determination of N—NO Bond Dissociation Energies of N-Nitrosoindoles and Their Radical Anions in Acetonitrile(2007)
- → Mechanistic pathways in phosphate ester photochemistry(1991)1 cited
- Determination of Heterolytic and Homolytic S_NO Bond Dissociation Energies in Acetonitrile(2000)