Abstract
Imidazopyrimidine derivatives are organic synthesized compounds with a pyrimido[l,2-a]benzimidazole as basic skeleton. They are known for their various biological properties and as an important class of compounds in medicinal chemistry. A new l,4-dimethyl-2-oxo-pyrimido[l,2-a]benzimidazole hydrate derivative of the tilted group has been synthesized and characterized by spectroscopic techniques NMR and FT-IR; and by a single crystal X-ray diffraction. The X-ray results showed that the tricyclic core of the title compound, C12H11N3O center dot H2O, is almost planar. The molecules stack along the a-axis direction in head-to-tail fashion through pi-stacking interactions involving all three rings. The stacks are tied together by direct C-H center dot center dot center dot O hydrogen bonds and by O-H center dot center dot center dot O, O-N center dot center dot center dot N and C-H center dot center dot center dot O hydrogen bonds with the lattice water. DFT calculations at B3LYP/6-311++G(d,p) in gas phase an polarizable continuum model have been carried out to predict the spectral and geometrical data of the tilted compound. The obtained results showed relatively good correlations between the predicted and experimental data with correlation coefficients higher than 98%. (c) 2017 Elsevier B.V. All rights reserved.