2683-68-3Relevant articles and documents
Acetyl exchange between pyridine N-oxides in acetonitrile solutions: An attempt to apply the Marcus equation to acetyl transfer
Rybachenko,Schroeder,Chotii,Titov,Kovalenko,Leska,Grebenyuk
, p. 1608 - 1615 (2001)
Forty-three (including eight identical) reactions of acetyl transfer from N-acetyloxypyridinium salts to pyridine N-oxides in acetonitrile solutions were studied. The rate constants k2 vary in the range 107-10-1 1 mol-1 s-1; the equilibrium constants K, in the range 107-10-7; the activation enthalpy ΔH≠, in the range 17-30 kJ mol-1; the activation entropy -ΔS≠, in the range 60-85 J mol-1 K-1; and the heat of reaction -ΔH0, within ±50 kJ mol-1. All reactions occur in a single stage by the concerted SN2 mechanism with a low degree of bond cleavage in the transition state. The rate and equilibrium of the acetyl exchange are satisfactorily described by the Bronsted equation. The quality of predicting the reactivity is substantially improved by introducing into the correlation equation a second parameter, the rates of identical reactions.
Rate and Equilibrium Constants of Dimethylcarbamoyl Transfer between Pyridine N-Oxides
Schroeder,Rybachenko,Chotii,Kovalenko,Grebenyuk,Lenska,Eitner
, p. 455 - 462 (2007/10/03)
Dimethylcarbamoyl transfer from N-acyloxypyridinium salts to pyridine N-oxides in acetonitrile occurs in one stage by the forced concerted SN2 mechanism. The rate and equilibrium of the reaction are fairly described by the Bronsted equation. The Marcus equation provides a much higher quality of reactivity predictions.
