Theoretical Calculation of Substituent Effects on the O-H Bond Strength of Phenolic Antioxidants Related to Vitamin E

摘要

Calculations on phenol and a large number of phenols substituted with methyl, methoxyl, and amino groups have yielded reliable gas-phase O-H bond dissociation energies, BDE(ArO-H)~gas. Geometries for the phenol, ArOH, and aryloxyl radical, ArO, were optimized at the (semiempirical) AM1 level followed by single point density functional theory (DFT) calculations using a 6-31G basis set supplemented with p-functions on the hydrogen atom and the B3LYP density functional.