2,6-Disubstituted 4-azidopyrimidines: synthesis, kinetic and thermodynamic studies of azide-tetrazole rearrangement by NMR spectroscopy

摘要

Thermodynamic and kinetic parameters of the tautomeric tetrazole-azide rearrangement for a series of 2,6-disubstituted 4-azidopyrimidines are determined by NOESY/EXSY and DNMR: Delta H = 15-28 kJ mol(-1); Delta S = 47-65 J mol(-1) De-1; D center dot (a) = 93-117 kJ mol(-1); lgA = 15.1-18.9. They are dependent on electronic properties of the substituents and the polarity of solvent.