Solvenseffekte bei der Photoinduzierten Elektronenübertragung von ungeladenen Donatoren auf Arendiazoniumsalze
1985; Wiley; Volume: 327; Issue: 3 Linguagem: Inglês
10.1002/prac.19853270307
ISSN0021-8383
Autores Tópico(s)CO2 Reduction Techniques and Catalysts
ResumoSolvent Effects in the Photoinduced Electron Transfer Reaction of Uncharged Donors with Arenediazonium Salts In the photochemical electron transfer reactions to arene diazonium salts no strong Coulomb forces arise but the rate constants possibly vary in dependence on the state of the diazonium salt (tight ion pair in nonpolar solvents or free diazonium cations). This problem is studied in the present work using anthracene and tetracene, respectively, as electron donors. They react in their S 1 states diffusion‐controlled with ion pairs ArN 2 ⊖ BF 4 ⊖ , whereas the respective triplet reactions proceed up to 10 3 times more slowly. These rates are not significantly influenced by the dielectric properties of the solvent. Thus, ion pairing of the diazonium salts in solvents of low polarity has no screening effect on the electron transfer. This behavior is explained including electrostatic effects into the MARCUS theory of outer sphere electron transfer processes. No indication of a Marcus inverted region was found.
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