ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

$^1H$ and $^{13}C$ NMR spectral studies of conformation of some N-(2-pyridinyl)-3-pyridinecarboxamides

Singha, Netai C and Sathyanarayana, DN (1998) $^1H$ and $^{13}C$ NMR spectral studies of conformation of some N-(2-pyridinyl)-3-pyridinecarboxamides. In: Journal of Molecular Structure, 449 (1). pp. 91-98.

[img] PDF
1H_and_13C-186.pdf
Restricted to Registered users only

Download (408Kb) | Request a copy

Abstract

The $^IH$ and $^{13}C$ NMR spectra of N-(2-pyridinyl)-, N-(4-methyl2-pyridinyl)-, and N-(6-methyl-2-pyridinyl)-3-pyridine-carboxamides (1-3, respectively) and 3-pyridinecarboxamide (4) in different solvents have been analysed using COSY, HETCOR, chemical shift and coupling constant correlations. The conformations of 1-4 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 1-3 dimerize through cooperative hydrogen bonding in con-centrated $CDCI_3$ 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 $(CD_3)_2CO$ and $CD_3CN$.

Item Type: Journal Article
Additional Information: Copyright of this article belongs to Esevier.
Keywords: NMR spectroscopy;Molecular conformation;Hydrogen bonding;Association;Pyridinecarboxamides
Department/Centre: Division of Chemical Sciences > Inorganic & Physical Chemistry
Date Deposited: 17 Jan 2007
Last Modified: 19 Sep 2010 04:34
URI: http://eprints.iisc.ernet.in/id/eprint/9522

Actions (login required)

View Item View Item