Theoretical study of the substituent effects on the S-H bond dissociation energy and ionization energy of 3-pyridinethiol: Prediction of novel antioxidant.
The S-H bond dissociation enthalpies [BDE(S-H)] of a set of 5-X- and 6-X-3-pyridinethiols (X = F, Cl, CH3, OCH3, NH2, N(CH3)2, CF3, CN, and NO2) have been computed using the density functional theory based (RO)B3LYP procedure with 6-311++G(2df,2p) basis set. The effects of substituents on the BDE(S-H), proton affinity of the pyridinethiol anion [PA(S-)] and ionization energy (IE) are analyzed and their correlations with Hammett's substituent constants are examined. Subsequently, a series of 6-substituted 3-pyridinethiols have been explored to find out their antioxidant potentials. Finally, a number of 3-pyridinethiol based compounds are theoretically proposed as novel antioxidants.
Nam
Pham Cam
PC
Department of Chemistry, University of Leuven, Celestijnenlaan 200F, B3001 Leuven, Belgium.
Nguyen
Minh Tho
MT
Chandra
Asit K
AK
D000975:Antioxidants / Q000737:chemistry*; D005609:Free Radicals; D006859:Hydrogen / Q000737:chemistry*; D006860:Hydrogen Bonding; D011725:Pyridines / Q000737:chemistry*; D011789:Quantum Theory; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013455:Sulfur / Q000737:chemistry*; D013816:Thermodynamics
C522331:3-pyridinethiol; D000975:Antioxidants; D005609:Free Radicals; D011725:Pyridines; D013438:Sulfhydryl Compounds; D013455:Sulfur; D006859:Hydrogen