69173-29-1Relevant academic research and scientific papers
Nucleophilic substitution at a four-coordinate sulfur atom. IV. Reactivity of anionic nitrogen-containing nucleopiles
Savelova,Karpichev,Simanenko,Prokop'eva,Lobachev,Belousova
, p. 530 - 539 (2007/10/03)
The second-order rate constants for reactions of anions derived from azoles, arenesulfonamides, and arenesulfonohydrazides with aryl toluenesulfonates and methyl iodide in 5% aqueous ethanol (μ 1.0) at 25°C were compared with corresponding rate constants for aliphatic and heterocyclic amines. The kinetic behavior of neutral and anionic nitrogen-containing bases in reactions involving acyl (4-nitrophenyl acetate and 4-nitrophenyl heptanoate) and toluenesulfonyl group transfer suggests that deviation from the Bronsted dependence is due to unfavorable solvation effects for nucleophiles with pKa ≥ 11.0 rather than to change in the transition state structure. In reactions with a soft substrate, methyl iodide, solvation effects scarcely play the determining role, and the reduced reactivity of the anionic nucleophiles relative to neutral species is most likely to result from structural differences in the transition states corresponding to methyl group transfer to neutral and anionic nitrogen-containing compounds. The α-effect with arenesulfonohydrazides was revealed for the first time. 1996 MAEe Cyrillic signΚ Hayκa/Interperiodica Publishing.
