Issue 6, 2004

Multiple hydrogen bonds and tautomerism in naphthyridine derivatives

Abstract

The behaviour of three 2,7-disubstituted 1,8-naphthyridines able to exhibit tautomerism has been studied by NMR in solution and in two cases in the solid state. The three derivatives studied are 2,7-dihydroxy- (1), 2-acetamido-7-amino- (3) and 2,7-diacetamido-1,8-naphthyridine (4). To explore the problem of secondary interactions, a series of complexes, with up to four simultaneous hydrogen bonds, where the monomers are generated using pyridine and 4-pyridone as building blocks, have been theoretically studied. The calculated interaction energies have been correlated with the number of hydrogen bonds and with attractive and repulsive secondary interactions. Further analysis of the electron density and orbital interactions shows that the secondary interactions, both attractive and repulsive, have a purely electrostatic origin. The X-ray structure of compounds 3 and 4 have been determined. In the solid state these compounds exist in the “diamino” tautomers with the N–H proton of the amido groups pointing towards the naphthyridine nitrogen. DFT and GIAO calculations have been essential to disentangle the problem of the structure of these compounds.

Graphical abstract: Multiple hydrogen bonds and tautomerism in naphthyridine derivatives

Supplementary files

Article information

Article type
Paper
Submitted
02 Dec 2003
Accepted
05 Feb 2004
First published
07 May 2004

New J. Chem., 2004,28, 700-707

Multiple hydrogen bonds and tautomerism in naphthyridine derivatives

C. Alvarez-Rua, S. García-Granda, S. Goswami, R. Mukherjee, S. Dey, R. M. Claramunt, M. D. Santa María, I. Rozas, N. Jagerovic, I. Alkorta and J. Elguero, New J. Chem., 2004, 28, 700 DOI: 10.1039/B315692C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements