title: Organochalcogen substituents in phenolic antioxidants.
abstract: Little is known about the ED/EW character of organochalcogen substituents and their contribution to the O-H bond dissociation enthalpy (BDE) in phenolic compounds. A series of ortho- and para-(S,Se,Te)R-substituted phenols were prepared and investigated by EPR, IR, and computational methods. Substituents lowered the O-H BDE by >3 kcal/mol in the para position, while the ortho-effect was modest due to hydrogen bonding ( approximately 3 kcal/mol) to the O-H group.
authors.affiliation: Department of Organic Chemistry A. Mangini, University of Bologna, Via S. Giacomo 11, I-40126 Bologna, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Amorati
authors.forename: Gian Franco
authors.initials: GF
authors.lastname: Pedulli
authors.forename: Luca
authors.initials: L
authors.lastname: Valgimigli
authors.forename: Henrik
authors.initials: H
authors.lastname: Johansson
authors.forename: Lars
authors.initials: L
authors.lastname: Engman
mesh_terms: D000975:Antioxidants / Q000138:chemical synthesis* / Q000737:chemistry; D018011:Chalcogens / Q000737:chemistry*; D008956:Models, Chemical; D015394:Molecular Structure; D010636:Phenols / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D000975:Antioxidants; D018011:Chalcogens; D010636:Phenols