Table of Contents
Journal of Crystallography
Volume 2014 (2014), Article ID 369061, 8 pages
Research Article

Crystallographic and DFT Studies on Pyrrolo[1,2-c]imidazole Scaffolds

1Centre for Bioinformatics, Pondicherry University, Puducherry 605014, India
2Department of Chemistry, Pondicherry University, Puducherry 605014, India

Received 30 October 2013; Accepted 17 February 2014; Published 14 April 2014

Academic Editor: Abdul Razak Ibrahim

Copyright © 2014 Manikandan Jayaraman et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The crystal structures of the compounds C15H14N4O2 (1) and C16H16N4O4 (2) are reported and analyzed by single crystal X-ray diffraction technique. Compounds (1) and (2) crystallized in monoclinic space group P21/c and Cc with four molecules in the unit cell, respectively. The unit cell parameters for compound (1) are = 11.4501(15) Å, = 9.7869(11) Å, = 12.3653(15) Å, β = 90.997(11)°, and Volume = 1385.5(3) Å3 and for compound (2) are = 13.865(2) Å, = 6.9538(8) Å, = 16.841(2) Å, β = 98.602(11)°, and Volume = 1605.4(4) Å3. In both compounds (1) and (2), the pyrrolidine ring adopts half-chair conformation. Moreover, both inter- and intramolecular N–HO hydrogen bonds stabilize the crystal structure and play a crucial role in crystal packing. This intermolecular interaction alone constructs chain motif in both compounds. It is also supported by weak intermolecular π-π interaction which is essential for the stability of the crystal packing. Further, the Density Functional Theory (B3LYP) method with standard 6-31G basis set was used in the calculation and calculated geometrical parameter is correlated with the corresponding experimental data. The obtained HOMO and LUMO energies are in negative values indicating that the compounds are in stable state.