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15N NMR substituent effects in pyridines and pyrimidines

✍ Scribed by W. Städeli; W. von Philipsborn

Publisher
John Wiley and Sons
Year
1981
Tongue
English
Weight
349 KB
Volume
15
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

^15^N chemical shifts of 32 substituted pyridines and 19 substituted pyrimidines, together with additional data from the literature, are used to evalute substituent increments, A~i~ and A~ik~, in the respective series. Differential chemical shifts, Δδ(N), correlate with corresponding Δδ(C) values whereby, on the ppm scale, nitrogen shifts are approximately three times more sensitive towards substituents than carbon shifts. The ^15^N increments have proven additive and useful for assignment purposes.

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