Crystal structure and Hirshfeld surface analysis of N,N′-[ethane-1,2-diylbis(oxy)]bis(4-methylbenzenesulfonamide)

In the crystal, the molecules are linked by N—H⋯O hydrogen bonds into supramolecular chains propagating along the [101] direction.


Chemical context
Sulfonamides are synthetic molecules which include the SO 2 -NH group and are called sulfa drugs. These effective drug molecules have an important role in the medical field, including as promising chemotherapeutic agents, and have been used in the treatment of many bacterial infections due to their physical, chemical and biological properties (Mahmood et al., 2016;Ghorab et al., 2018). Recently, sulfonamides have also been used in the organic synthesis reactions for the synthesis of linear or cyclic oligomers and the introduction of nucleophilic heteroatom functionality to the synthesized molecule (Ni et al., 2015). N,N 0 -ditosylalkane diamine is a disulfonamide synthesized by the tosylation of diamine, and this synthetic molecule has antibacterial properties (Alyar et al., 2011) and has also been used in many organic synthesis reactions (Rong et al., 1998). In this study, the synthesis, crystal structure and Hirshfeld surface analysis are reported for the new potential sulfa drug, N,N 0 -[ethane-1,2-diylbis(oxy)]bis(4methylbenzenesulfonamide).

Supramolecular features
The crystal packing of the title compound features intermolecular N-HÁ Á ÁO hydrogen bonds (Table 1 and Fig. 2), which connect the molecules into supramolecular chains propagating along the [101] direction. The chains are linked by pairs of C-HÁ Á ÁO hydrogen bonds (Table 1, Fig. 3), forming a framework with small cavities of 99 Å 3 , ca 5% of the unit-cell volume.

Hirshfeld surface analysis
Hirshfeld surface analysis is a method for visualizing the interactions present in the crystal structure and providing quantitative information about them. The d norm representation of the Hirshfeld surface reveals the close contacts of hydrogen-bond donors and acceptors, but other close contacts are also evident. The molecular Hirshfeld surfaces were generated using a standard (high) surface resolution with the three-dimensional d norm surfaces mapped over a fixed colour scale of À0.464 (red) to 2.052 (blue) Å using the Crystal-Explorer  Table 1 Hydrogen-bond geometry (Å , ).

Figure 2
A view of the chain structure formed by N-HÁ Á ÁO hydrogen bonding.

Figure 1
The molecular structure of the title compound, showing the atom labelling. Displacement ellipsoids are drawn at the 20% probability level. Symmetry code: (a) Àx, y, Àz À 1 2 .

Figure 3
A view along the b-axis of the crystal packing of the title compound. The hydrogen bonds (Table 1) are shown as dashed lines.
bonds. In Figs. 4 and 5, the identified red spot is attributed to the HÁ Á ÁO close contacts which are due to the N-HÁ Á ÁO hydrogen bonds (Table 1). The Hirshfeld surface of the title compound mapped over d norm , d i and d e .

Figure 5
Hirshfeld surface mapped over d norm to visualize the intermolecular interactions in the title compound.

Figure 6
The overall fingerprint plot for the title compound.  The HÁ Á ÁH plot shown in Fig. 7 shows the two-dimensional fingerprint of the (d i , d e ) points associated with hydrogen atoms. It is characterized by an end point that points to the origin and corresponds to d i = d e = 1.08 Å , which indicates the presence of the HÁ Á ÁH contacts in this study (43.1%). The CÁ Á ÁH/HÁ Á ÁC plot in Fig. 7 shows the contact between the carbon atoms inside the surface and the hydrogen atoms outside the surface of Hirshfeld and vice versa. There are two symmetrical wings on the left and right sides (8.8%). Furthermore, there are CÁ Á ÁC (5.5%), NÁ Á ÁH/HÁ Á ÁN (1.4%), OÁ Á ÁC/CÁ Á ÁO (0.1%) and SÁ Á ÁH/HÁ Á ÁS (0.1%) contacts in the title structure.
A view of the three-dimensional Hirshfeld surface of the title compound plotted over electrostatic potential energy in the range À0.095 to 0.123 a.u. using the STO-3G basis set at the Hartree-Fock level of theory is shown in Fig. 8 where the N-HÁ Á ÁO hydrogen-bond donors and acceptors are shown as blue and red areas around the atoms related with positive (hydrogen-bond donors) and negative (hydrogen-bond acceptors) electrostatic potentials, respectively.

Synthesis and crystallization
The title compound was synthesized according to the method of Bauer & Suresh (1963). Single crystals (m.p. 414-415 K) were obtained from an ethanol solution (yield 93%)

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2. C-bound H atoms were positioned geometrically (C-H = 0.93-0.97 Å ) and refined as riding, with U iso (H) = 1.5U eq (C-methyl) and 1.2U eq (C) for other H atoms. The NH H atom was located in a difference-Fourier maps and freely refined.    SHELXL2017 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

N,N′-[Ethane-1,2-diylbis(oxy)]bis(4-methylbenzenesulfonamide)
Crystal data Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.