Singh, Netai C and Sathyanarayana, DN (1998) 1H and 13C NMR spectral studies of conformation of some N-(2-pyridinyl)-3-pyridinecarboxamides. In: Journal of Molecular Structure, 449 (1). pp. 91-98.
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The 1H and 13C NMR spectra of N-(2-pyridinyl)-, N-(4-methyl2-pyridinyl)-, and N-(6-methyl-2-pyridinyl)-3-pyridine-carboxamides (1ï¿½3, respectively) and 3-pyridinecarboxamide (4) in different solvents have been analysed using COSY, HETCOR, chemical shift and coupling constant correlations. The conformations of 1ï¿½4 have been obtained by utilizing the NMR spectra, NOE experiments and MINDO/3 calculations. In dilute solutions, the 2-pyridyl ring is coplanar with the amide group while the 3-pyridyl ring is apparently not. Compounds 1ï¿½3 dimerize through cooperative hydrogen bonding in concentrated CDCl3 solution (approximately 0.1 M) and the structure of the dimer resembles some of the DNA base-pairs. Hydrogen bonding between N---H and the solvent molecules hinders dimerization in (CD3)2CO and CD3CN.
|Item Type:||Journal Article|
|Additional Information:||Copyright of this article belongs to Elsevier science.|
|Keywords:||NMR spectroscopy;Molecular conformation;Hydrogen bonding; Association;Pyridinecarboxamides.|
|Department/Centre:||Division of Chemical Sciences > Inorganic & Physical Chemistry|
|Date Deposited:||09 Jun 2011 07:19|
|Last Modified:||09 Jun 2011 07:19|
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