Arnett, Edward M. published the artcileSolvent effects in organic chemistry. VIII. Acidity function failure in different aqueous acids, Formula: C8H11N3O2, the main research area is .
cf. CA 62, 13908d. Acidity functions (H0′, H0”’, and HR) are given for primary and tertiary aromatic amines and triarylcarbinols in aqueous HCl, H3PO4, and p-toluenesulfonic acids. In all of these media, and H2SO4, the order in which the acidity functions change with acid concentration is HR > HR’ > H0”’ > H0′. Using such functions as H0”’ – H0′ (i.e., log fB’fB”’H+/fB’H+fB”’) as a criterion of acidity function failure, it is found that these terms have a roughly linear relationship to the acid molarity in these media and in HClO4, but give variously shaped curves if plotted against log aH2O. The slopes of the linear Sechenov-like plots for (HR’ – H0′) in these acids fall in the order HClO4 > H2SO4 > HePO4 > HCl, suggesting that H2SO4 and HClO4 are the worst media of the four as far as acidity function failure is concerned. The importance of factors (such as size) other than ion hydration in determining activity coefficient and, hence, acidity functions is noted. It is suggested that the failure of rates of acid-catalyzed reactions to give linear plots of log k1 vs. H0 of unit slope be treated in a similar way. Plots of (log k1 + H0) vs. molarity of acid are linear over a fair range of acidity in conformity with the Sechenov-like equation log fSfBH+ /f*fB = constant × molarity. Aqueous solutions of p-toluenesulfonic acid give a medium in which H0′ and H0”’ are very close together and might be a useful one for acidity function work. However, the solutions are only weakly acidic compared to the mineral acids and present a very limited range of acidities.
Journal of the American Chemical Society published new progress about Acidity function. 5472-46-8 belongs to class pyrimidines, name is Ethyl 4-amino-2-methylpyrimidine-5-carboxylate, and the molecular formula is C8H11N3O2, Formula: C8H11N3O2.
Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia