Novel pyridyl-substituted coumarin and its perchlorate salt-crystal structure and spectroscopic properties

Abstract

The novel pyridyl-substituted coumarin (1) and its perchlorate salt (2) have been synthesized and their structure and properties elucidated in detail spectroscopically, thermally and structurally, using single crystal X-ray diffraction for 2, linear-polarized solid state IR-spectroscopy, UV-spectroscopy, TGA, DSC, DTA, and positive and negative ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and electronic spectra. The studied compound crystallizes in the centrosymmetric space group P-1 and exhibits an infinite layered structure with the ions linked by means of the intermolecular N+H⋯.OClO 3 (2.795 Å) interactions. The cations are disposed in a manner leading to a significant π-stacking effect with a distance of 3.163 AA. The effects of Npy protonation on the optical and magnetic properties are elucidated by comparing the data of the protonated and neutral compounds. Copyright © 2009 John Wiley & Sons, Ltd.