On the Possibility of Tuning Molecular Edges To Direct Supramolecular Self-Assembly in Coumarin Derivatives through Cooperative Weak Forces: Crystallographic and Hirshfeld Surface Analyses

Abstract

Four organic compounds based on substituted coumarin derivatives (1–4) have been synthesized and characterized by X-ray structural studies with a detailed analysis of Hirshfeld surface and fingerprint plots facilitating a comparison of intermolecular interactions in building different supramolecular architectures. The X-ray study reveals that in the molecular packing C–H···O, π···π, and carbonyl (lone pair)···π interactions cooperatively take part. The recurring feature of the self-assembly in all the compounds is the appearance of the molecular ribbon through weak hydrogen bonding. These hydrogen bonded ribbons further stacked into molecular layers by π···π forces. The mode of cooperativity of the weak C–H···O and π···π forces is such that they operate in mutually perpendicular directions  hydrogen bonding in the plane of the molecule at their edges and π-stacking perpendicular to the molecular plane. Investigation of intermolecular interactions and crystal packing via Hirshfeld surface analyses reveals that more than two-thirds of the close contacts are associated with weak interactions. Hirshfeld surface and breakdown of the corresponding fingerprint plots of four coumarin structures clearly quantify the interactions within the crystal structures, revealing significant similarities in the interactions experienced by each compound. The binding energies associated with the weak interactions have been estimated using density functional theory calculations.

Different supramolecular architectures mediated by different weak interactions in the crystals of three N-aryl-2,5-dimethoxybenzenesulfonamides

“…The Hirshfeld surface analyses were carried out and fingerprint plots (FPs) were plotted using the CrystalExplorer3.0 software (Wolff et al, 2001;Seth et al, 2011;Saikat et al, 2013). The d norm plots were mapped with a colour scale between À0.18 (blue) and +1.4 au (red).…”

A new non-centrosymmetric microporous fluorinated iron phosphate: Structural elucidation, spectroscopic study and Hirshfeld surface analysis

“…The intermolecular interactions [31][32][33][37][38][39][40][41][42][43][44] in the crystal structure were quantified using Hirshfeld surface analysis and the associated 2D fingerprint plots [45][46][47] were calculated via the Crystal Explorer 3.0 [48] , which accepts a structure input file in the CIF format. This approach has been built on the electron distribution calculated as the sum of spherical atom electron densities [49,50] .…”

“…The identification of intermolecular interactions has been realized for the water molecule from the Hirshfeld surface [31][32][33] showing that the surface has been mapped over a d norm (normalized contact distance) in the range of -0.0781-0.0898 nm (Fig.4). The second most intense interaction is the H···H interaction in the order of 23.3%.…”

“…In fact, the analyses of the most important step of how molecules interact with their direct environment presenting a considerable barrier in the understanding and communication of structure and its relationship to properties were undertaken. Therefore, Hirshfeld surface [25][26][27][28][29][30][31][32][33] based tools represent a new approach to this problem.…”

Crystals of 4-(2-benzimidazole)-1,2,4-triazole and its hydrate: preparations, crystal structure and Hirshfeld surfaces analysis

“…When the cif files of crystals 1 and 2 were read into the CrystalExplorer program for analysis, all bond lengths to hydrogen were automatically modified to typical standard neutron values (C-H = 1.083 Å and N-H = 1.009 Å ). The 2D fingerprint plots [33][34][35] were displayed by using the standard 0.5-2.5 Å view with the d e and d i distance scales were displayed on the graph axes.…”