- The Trialkylhydrazyl-Trialkylhydrazine Radical Cation Proton Transfer. 1. Equilibrium Constant
-
Pulse radiolytically generated eaq- and *C(CH3)2OH in water reduce trialkyldiazenium salts (R3N2+) to hydrazyl radicals (R3N2*), which protonate to give hydrazine radical cations (R3N2H+*).Determination of pKa (R3N2H+*) by conductivity measurements gave 7.0 (+/- 0.4), 8.3 (+/- 0.2), and 10.4 (+/- 0.2) for the radical cations of 2-tert-butyl 2,3-diazabicycloheptane (1H+*), its 7-spirocyclopropyl analogue (2H+*), 2-tert-butyl-2,3-diazabicyclooctane (3H+*), and 9-tert-butylamino-9-azabicyclononane (4H+*), respectively.The respective values for pKa (R3N2H2+) - pKa (R3N2H+*) are +2.1, +2.4, +1.2, and -2.6.The hydrazyl radical and hydrazine radical cation have similar absorption spectra except for system 4, where a significant red shift in UV maximum of the hydrazyl relative to that of the hydrazine radical cation was observed.The deviant behavior of the N,N-cycloalkyl compound 4 from the N,N'-cycloalkyl compounds 1 - 3 is argued to result from 4* being more twisted about the NN bond than 4H*, while such twisting does not occur in the N,N'-cycloalkyl systems.
- Nelsen, Stephen F.,Parmelee, William P.,Goebl, Manfred,Hiller, Karl-Otmar,Veltwisch, Dieter,Asmus, Klaus-Dieter
-
-
Read Online