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Nitrogen-15 nuclear magnetic resonance studies of hydrogen bonding and proton transfer in some pyridine trifluoroacetates in dichloromethane

✍ Scribed by Z. Dega-Szafran; M. Szafran; L. Stefaniak; C. Brevard; M. Bourdonneau

Publisher
John Wiley and Sons
Year
1986
Tongue
English
Weight
399 KB
Volume
24
Category
Article
ISSN
0749-1581

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✦ Synopsis

The "N NMR chemical shifts of ten substituted pyridines (B) and their complexes with trifluoroacetic acid (AHB) were measured at the natural abundance level in dichloromethane. The plot of the relative chemical shifts [A6("N) = G(AHB) -6(B)] against ApK, gives a titration curve which reflects a protometric eauilibrium AH -B $ A--* * HB+. These data were used to determine the constants of the transfer reaction (Kerp). A linear relationship holds between log Keap and ApK,. A6(15N) treated as a good hydrogen bond parameter. KEY WORDS I5N NMR spectroscopy Hydrogen bond Proton transfer Pyridines overall proton values can be

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