1783-35-3Relevant academic research and scientific papers
Amidines. Part 39.1 Formation of N1,N1-dialkylamidines in the reaction between amide acetals and substituted anilines in pyridine. Reaction mechanisms
Oszczapowicz, Janusz,Osek, Jerzy
, p. 1919 - 1923 (2007/10/03)
The reaction rates of six N,N-dialkylformamide acetals (R1)2N-CH(OR2)2, with a series of anilines substituted on the phenyl ring have been measured in pyridine. The reaction is found to be irreversible and obeys second-order kinetics. Reaction rates are correlated with Hammett σ constants. Based on the plots and a comparison of reaction rate constants it is shown that the reaction proceeds via two mechanisms which differ from that for the reaction in neutral solvents. It is shown that for compounds with weakly basic NH2 groups the reaction rates in pyridine are markedly higher than in neutral solvents.
Amidines. Part 31. pKa Values of N1,N1-Dialkyl-N2-phenylformamidines in Water-Ethanol Solutions
Oszczapowicz, Janusz,Jaroszewska-Manaj, Jolanta
, p. 1677 - 1680 (2007/10/02)
The pKa values of three series (30 compounds in all) of N1,N1-dialkyl-N2-phenylformamidines (XC6H4N=CHNRR) have been measured in water-ethanol mixtures.The obtained pKa values of the amidines have been correlated with Hammett-type substituent constants and the pKa values of the corresponding primary amines determined in the same solvent.The applicability of various ? values is discussed and it is shown that, in each case, for substituents on the phenyl ring at the amino nitrogen atom ?0 values should be used.It is found that the slopes of regression lines for correlations with Hammett-type constants depend on the substituents at the amino nitrogen atom, as well as on the solvent.
Amidines. Part 20. Rate of Reaction of N,N-Dialkylformamide Acetals with Substituted Anilines
Osek, Jerzy,Oszczapowicz, Janusz,Drzewinski, Witold
, p. 1961 - 1964 (2007/10/02)
Rate of reaction of seven N,N-dialkylformamide acetals R2N-CH(OR2)2 with a series of anilines substituted on the phenyl ring have been measured in benzene, methanol, chloroform, and tetrahydrofuran by use of a g.l.c. method.In each case studied reaction is irreversible and obeys a second-order kinetic equation.Reaction rates correlate with Hammett ? constants for substituents on the phenyl ring of the aniline molecule.On the basis of the kinetic data, the mechanism of reaction is discussed.
