84487-09-2Relevant academic research and scientific papers
Substituent Effects on the Isomer Ratios in the Rearrangement of Some 2- and 4-Nitraminopyridines
Deady, Leslie W.,Korytsky, Olga L.,Rowe, Jeffrey E.
, p. 2025 - 2034 (2007/10/02)
The preparation, and rearrangement in 92percent sulfuric acid, of 4-X-2-nitramino- (1), 2-X-4-nitramino- (2), and 6-X-2-nitramino-pyridines (3) is reported (X=H,Me,MeO,Br,Cl,CO2H).The product isomer ratios can be explained by differential electronic stabilization of the appropriate ? complexes for aromatic nitration and steric effects seem relatively unimportant.Deuteration had no effect on the product distribution
Kinetic Studies of the Mechanism of the Nitraminopyridine Rearrangement
Deady, Leslie W.,Korytsky, Olga L.
, p. 2035 - 2040 (2007/10/02)
Rate data are reported for the rearrangement, in 92percent sulfuric acid at 30 deg C, of a series of 4-X-2-nitraminopyridines (X=H, Me, Br, Cl, MeO, CO2H) and of 4-methyl-2-nitramino(3-D)-pyridine.Values of pKa for second protonation of the corresponding pyridin-2-amines were also measured and rate constants for nitration of the monoprotonated pyridinamines were thereby calculated.The results suggest that the rate-determining step occurs prior to formation of the appropriate 3- and 5-nitro ? complexes.The nature of this step is not clear, however, and a key role for the nitramine itself is not proven by the current evidence
