The redox chemistry of sulfenic acids.
A persistent triptycenyl sulfenic acid is used as a model for cysteine-derived and other biologically relevant sulfenic acids in experiments which define their redox chemistry. EPR spectroscopy reveals that sulfinyl radicals are persistent and unreactive toward O(2), allowing the O-H bonding dissociation enthalpy (BDE) of the sulfenic acid to be readily determined by equilibration with TEMPO as 71.9 kcal/mol. The E° (RSO•/RSO(-)) and pK(a) of this sulfenic acid are also reported.
Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6.
Alaina J
AJ
McGrath
Graham E
GE
Garrett
Luca
L
Valgimigli
Derek A
DA
Pratt
D004563:Electrochemistry; D004578:Electron Spin Resonance Spectroscopy; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D013434:Sulfenic Acids / Q000737:chemistry*; D013816:Thermodynamics
D013434:Sulfenic Acids; D010100:Oxygen