Dissociations of free radicals to generate protons, electrophiles or nucleophiles: role in DNA strand breaks

Abstract

The concept behind the research described in this article was that of marrying the ‘soft’ methods of radical generation with the effectiveness and flexibility of nucleophile/electrophile synthetic procedures.

Application of the Spin-Center Shift in Organic Synthesis

“…Based on previous reports and some recent studies, 10,11 a general consensus about SCS processes has been summarized: (1) the singly occupied molecular orbital (SOMO) and the σ*orbital of the leaving group should be in an approximate coplanar arrangement to provide sufficient orbital overlap that is essential for the efficient heterolysis of the C−X bond and the shift of the spin-center; (2) a sufficiently good leaving group is required, or Brønsted or Lewis acid or base should be added to aid the elimination of the leaving group; and (3) the existence of an adjacent electron-donating substituent/atom at the radical center is helpful to the SCS process, as it stabilizes the generated radical cation. With numerous photoredox catalysts covering a broad range of redox potentials, photoredox catalysis has emerged as a powerful platform which facilitates a myriad of organic transformations.…”

Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical

“…Consistent with the findings of previous ab initio studies, our results suggest that the inclusion of microhydration is needed to correctly reproduce the chemical stability of radical species in aqueous solution. 53,74–78 It is important to note that energy residing within other vibrational modes, including those of the solvent bath, can promote the statistical fragmentation of the Phe˙ radical, albeit on timescales beyond the few picoseconds probed in the current experiments.…”

Synergetic Oxidation of the Hydroxyl Radical and Superoxide Anion Lowers the Benzoquinone Intermediate Conversion Barrier and Potentiates Effective Aromatic Pollutant Mineralization

“…Free-radical-mediated heterogeneous catalytic oxidation is at the heart of many potential applications, most importantly in chemosynthesis, biotherapy, and environmental remediation. − For a long time, the researchers put a lot of effort and made extraordinary achievement in constructing a microenvironment with high free radical density to improve catalytic efficiency by increasing the effective collision between free radicals and targets. , All the while, however, another important issue has been neglected; that is, the free radical as an energy carrier has more than just wide varieties but distinct properties . The free radicals with single form or the same nature are often far from adequate for the entire catalytic reaction process.…”