The 1-methyl-4-tert-butylpyridinyl radical can be in equilibrium with the 2,2 dimer which shows photolytic cleavage to generate the radical. The dimer structure was offered from the results of 1H and 13C NMR measurements. The dimerization rate (k) evaluated from the kinetic ESR measurements can be represented by log (k/M-1 s-1) = 8.55 - 2.02 (kcal/mol)/θ, where θ = 2.303RT. Time-resolved ESR experiments for the photolytic cleavage of the dimer revealed that the precursor of the radical generation was a singlet radical pair, exhibiting an A/E polarization pattern in the transient ESR spectra.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry