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Long range 13C1H coupling constants IV—methoxy-, amino- and hydroxypyridines

✍ Scribed by Yoshito Takeuchi; Nicholas Dennis

Publisher
John Wiley and Sons
Year
1975
Tongue
English
Weight
285 KB
Volume
7
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

One bond and long range ^13^C^1^H coupling constants for some methoxy‐, amino‐ and hydroxypyridines are described. An unambiguous assignment of carbon‐13 resonances is carried out based on the analysis of the fine splitting caused by long range couplings. J values for compounds other than 2‐ and 4‐hydroxy‐pyridines are explainable in terms of the values previouly obtained for cyano‐ and methylpyridines. The hydroxypyridine‐pyridone tautomerism affects ^2^J(H~α~), i.e. ^2^J associated with the α proton. This effect can be used to differentiate pyridones from hydroxypyridines.

📜 SIMILAR VOLUMES

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