74530-34-0Relevant articles and documents
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.