Excellent correlation between substituent constants and pyridinium N-methyl chemical shifts.
Substituents on the pyridinium ring of N-methylpyridinium derivatives, especially those on the 2- or 4-positions, have a large effect on the (1)H and (13)C NMR chemical shifts of the N-methyl group. Reasonable correlations between the chemical shift changes and the resonance substituent constants are observed. The dual substituent parameter approach provides an excellent correlation when a combination of polar and resonance substituent constants is employed.
Huang
Sha
S
Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, CA 94132.
Wong
Jesse C S
JC
Leung
Adam K C
AK
Chan
Yee Man
YM
Wong
Lili
L
Fernendez
Myrien R
MR
Miller
Amanda K
AK
Wu
Weiming
W