Enantiomerization kinetics studied by dynamic enantioselective liquid chromatography: Solvent, temperature and stationary phase effects on the rate of N-benzyl-1,3,2-benzodithiazole 1-oxide enantiomer interconversion

Abstract

Enantiomerization of 1 was found to proceed ca. 10 times faster in hexane than in methanol. This has been attributed to the difference in ΔS ^‡ found in the respective solvents. The presence of a chiral HPLC stationary phase (Whelk-O1) did not affect the rate of enantiomerization to any significant extent. The previously determined enantiomerization (by inversion of configuration) barrier of 2 using DHPLC (80 kJ mol^–1), is thus considered correct, and not biased by the presence of the stationary phase.