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ISSN: 2056-9890

Crystal structure, Hirshfeld surface analysis and computational study of the 1:2 co-crystal formed between N,N′-bis­­[(pyridin-4-yl)meth­yl]ethanedi­amide and 3-chloro­benzoic acid

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aResearch Centre for Crystalline Materials, School of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
*Correspondence e-mail: edwardt@sunway.edu.my

Edited by M. Weil, Vienna University of Technology, Austria (Received 6 May 2020; accepted 15 May 2020; online 19 May 2020)

The asymmetric unit of the title 1:2 co-crystal, C14H14N4O2·2C7H5ClO2, comprises a half-mol­ecule of oxalamide (4LH2), being located about a centre of inversion, and a mol­ecule of3-chloro­benzoic acid (3-ClBA) in a general position. From symmetry, the 4LH2 mol­ecule has a (+)anti­periplanar conformation with the 4-pyridyl residues lying to either side of the central, planar C2N2O2 chromophore with the dihedral angle between the core and pyridyl ring being 74.69 (11)°; intra­molecular amide-N—H⋯O(amide) hydrogen bonds are noted. The 3-ClBA mol­ecule exhibits a small twist as seen in the C6/CO2 dihedral angle of 8.731 (12)°. In the mol­ecular packing, three-mol­ecule aggregates are formed via carb­oxy­lic acid-O—H⋯N(pyrid­yl) hydrogen bonding. These are connected into a supra­molecular tape along [111] through amide-N—H⋯O(carbon­yl) hydrogen bonding. Additional points of contact between mol­ecules include pyridyl and benzoic acid-C—H⋯O(amide), methyl­ene-C—H⋯O(carbon­yl) and C—Cl⋯π(pyrid­yl) inter­actions so a three-dimensional architecture results. The contributions to the calculated Hirshfeld surface are dominated by H⋯H (28.5%), H⋯O/O⋯H (23.2%), H⋯C/C⋯H (23.3%), H⋯Cl/Cl⋯H (10.0%) and C⋯Cl/C⋯Cl (6.2%) contacts. Computational chemistry confirms the C—Cl⋯π inter­action is weak, and the importance of both electrostatic and dispersion terms in sustaining the mol­ecular packing despite the strong electrostatic term provided by the carb­oxy­lic acid-O—H⋯N(pyrid­yl) hydrogen bonds.

1. Chemical context

Herein, the X-ray crystal structure determination of the 1:2 co-crystal formed between bis­(pyridin-4-ylmeth­yl)ethanedi­amide and 3-chloro­benzoic acid, (I)[link], is described. The present crystallographic study continues recent studies into the structural chemistry of the isomeric bis­(pyridin-n-ylmeth­yl)ethanedi­amide mol­ecules, i.e. species with the general formula n-NC5H4CH2N(H)C(=O)C(=O)CH2C5H4N-n, for n = 2, 3 and 4, and hereafter, abbreviated as nLH2 (Tiekink, 2017[Tiekink, E. R. T. (2017). Multi-Component Crystals: Synthesis, Concepts, Function, edited by E. R. T. Tiekink & J. Schpector-Zukerman, pp. 289-319. Singapore: De Gruyter.]). These mol­ecules have inter­est as co-crystal co-formers as they possess both hydrogen-bonding donating and accepting sites, i.e. amide and pyridyl functionalities. A particular focus of these studies has been upon co-crystals formed with carb­oxy­lic acids (Arman et al., 2012[Arman, H. D., Miller, T. & Tiekink, E. R. T. (2012). Z. Kristallogr. Cryst. Mater. 227, 825-830.], 2014[Arman, H. D., Kaulgud, T., Miller, T. & Tiekink, E. R. T. (2014). Z. Kristallogr. Cryst. Mater. 229, 295-302.]; Tan, Halcovitch et al., 2019[Tan, S. L., Halcovitch, N. R. & Tiekink, E. R. T. (2019). Acta Cryst. E75, 1133-1139.]; Tan & Tiekink, 2019[Tan, S. L. & Tiekink, E. R. T. (2019). Z. Kristallogr. New Cryst. Struct. 234, 1109-1111.]), directed by the reliability of the carb­oxy­lic acid-O—H⋯N(pyrid­yl) synthon (Shattock et al., 2008[Shattock, T. R., Arora, K. K., Vishweshwar, P. & Zaworotko, M. J. (2008). Cryst. Growth Des. 8, 4533-4545.]). A common thread of recent investigations has been upon benzoic acid (Tan & Tiekink, 2020a[Tan, S. L. & Tiekink, E. R. T. (2020a). Acta Cryst. E76, 102-110.]) and derivatives (Syed et al., 2016[Syed, S., Jotani, M. M., Halim, S. N. A. & Tiekink, E. R. T. (2016). Acta Cryst. E72, 391-398.]), in particular halide-substituted species (Tan & Tiekink, 2020b[Tan, S. L. & Tiekink, E. R. T. (2020b). Acta Cryst. E76, 245-253.]) in order to probe for the possibility of competing/complementary halogen-bonding inter­actions. In connection with this theme, this report describes the crystal and mol­ecular structures of (I)[link], along with a detailed analysis of the supra­molecular association through the calculation of the Hirshfeld surface and computational chemistry.

[Scheme 1]

2. Structural commentary

The asymmetric unit of (I)[link] comprises a mol­ecule of 4-chloro­benzoic acid (3-ClBA) in a general position and one-half mol­ecule of 4LH2, being disposed about a centre of inversion, Fig. 1[link]. In the acid, 3-ClBA, there is a definitive disparity in the C8—O2 [1.225 (2) Å] and C8—O3 [1.308 (2) Å] bond lengths entirely consistent with the localization of the acidic proton on the O3 atom. This is also borne out in the angles subtended at the C8 atom with the widest angle involving the oxygen atoms [O2—C8—O3 = 123.38 (17)°] and the narrowest involving the atoms connected by a single bond [O3—C8—C9 = 114.23 (15)°]. A small twist in the mol­ecule is evident as seen in the dihedral angle of 8.731 (12)° formed between the CO2/C6 residues; the O2—C8—C9—C10 torsion angle = 171.79 (19) Å.

[Figure 1]
Figure 1
The mol­ecular structures of the constituents of co-crystal (I)[link] showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level: (a) the 3-chloro­benzoic acid mol­ecule and (b) the centrosymmetric N,N′-bis­[(pyridin-4-yl)meth­yl]oxalamide mol­ecule with the unlabelled atoms related by the symmetry operation (i) 1 − x, − y, − z.

The 4LH2 mol­ecule is situated about a centre of inversion so the central C2N2O2 chromophore is constrained to be planar. As is normal for nLH2 mol­ecules (Tiekink, 2017[Tiekink, E. R. T. (2017). Multi-Component Crystals: Synthesis, Concepts, Function, edited by E. R. T. Tiekink & J. Schpector-Zukerman, pp. 289-319. Singapore: De Gruyter.]), the central C7—C7i [1.539 (3) Å; symmetry code: (i) 1 − x, − y, − z] bond length is considered long, an observation ascribed to the electronegative substituents bound to the sp2-C7 atom. The conformation of the 4LH2 mol­ecule is (+)anti­periplanar so the 4-pyridyl residues lie to either side of the planar region of the mol­ecule. The dihedral angle between the central core and the N1-pyridyl ring is 74.69 (11)°. Owing to the anti-disposition of the amide groups intra­molecular amide-N—H⋯O(amide) hydrogen bonds are formed which complete S(5) loops, Table 1[link].

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the (N1,C1–C5) ring.

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2N⋯O1i 0.86 (2) 2.34 (3) 2.717 (2) 107 (2)
N2—H2N⋯O2ii 0.86 (2) 2.08 (2) 2.863 (2) 151 (2)
O3—H3O⋯N1iii 0.84 (2) 1.74 (2) 2.581 (2) 174 (4)
C14—H14⋯O1iv 0.95 2.37 3.286 (2) 161
C1—H1⋯O1v 0.95 2.39 3.286 (3) 157
C12—H12⋯O1vi 0.95 2.46 3.328 (3) 152
C6—H6A⋯O3 0.99 2.50 3.400 (3) 151
C13—Cl1⋯Cg1 1.75 (1) 3.83 (1) 5.358 (2) 145 (1)
Symmetry codes: (i) -x+1, -y, -z; (ii) -x+1, -y+1, -z+1; (iii) x-1, y, z; (iv) x, y+1, z+1; (v) -x+2, -y+1, -z; (vi) x+1, y+1, z+1.

3. Supra­molecular features

The most distinctive feature of the mol­ecular packing is the association between 4LH2 and two symmetry-related 3-ClBA mol­ecules via carb­oxy­lic acid-O—H⋯N(pyrid­yl) hydrogen bonding, Table 1[link], to generate a three-mol­ecule aggregate. These three-mol­ecule aggregates are connected into a linear tape along [111] via amide-N—H⋯O(carbon­yl) hydrogen bonds Fig. 2[link](a). These give rise to 22-membered {⋯NC4NH⋯OCOH}2 synthons. Additional stability to the hydrogen-bonding arrangement is provided by supporting benzoic acid-C14—H⋯O(amide) inter­action which lead to non-symmetric 10-membered {⋯HC3O⋯HNC2O}2 synthons, which flank the larger 22-membered rings. Further, a complementary C—Cl⋯π(pyrid­yl) contact is noted, as detailed in Table 1[link]. A survey of the literature (Imai et al., 2008[Imai, Y. N., Inoue, Y., Nakanishi, I. & Kitaura, K. (2008). Protein Sci. 17, 1129-1137.]) as well as the Cambridge Structural Database (Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) shows that the average Cl⋯π distance is about 3.6 Å, which is shorter than the contact distance in (I)[link]. An end-on view of the tape is shown in Fig. 2[link](b). The tapes are connected into a supra­molecular layer by relatively short pyridyl-C1—H⋯O(amide) contacts, Fig. 2[link](c). A three-dimensional architecture results when benzoic acid-C12—H⋯O(amide) and methyl­ene-C—H⋯O(carbon­yl) inter­actions are taken into consideration, Fig. 2[link](d). In this scheme, the amide-O1 atom participates in three pivotal C—H⋯O inter­actions.

[Figure 2]
Figure 2
Mol­ecular packing in the crystal of (I)[link]: (a) a view of the supra­molecular tape comprising three-mol­ecule aggregates (sustained by carb­oxy­lic acid-O—H⋯N(pyrid­yl) hydrogen bonding shown as orange dashed lines) linked by amide-N—H⋯O(carbon­yl) hydrogen bonding (blue dashed lines) and supporting benzoic acid-C—H⋯O(carbon­yl) inter­actions (green dashed lines), (b) an end-on view of the tape viewed down [111], (c) a view of the supra­molecular layer whereby the tapes of (a) are linked by short pyridyl-C—H⋯O(carbon­yl) inter­actions and (d) a view of the unit-cell contents down the a axis.

4. Hirshfeld surface analysis

The Hirshfeld surface analysis was performed for the three-mol­ecule aggregate of (I)[link], i.e. that sustained by the carb­oxy­lic acid-O—H⋯N(pyrid­yl) hydrogen bonds, and for the individual components, viz. the full mol­ecule of 4LH2 and 3-ClBA, with the use of CrystalExplorer17 (Turner et al., 2017[Turner, M. J., Mckinnon, J. J., Wolff, S. K., Grimwood, D. J., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). Crystal Explorer 17. The University of Western Australia.]) and based on established methods (Tan, Jotani et al., 2019[Tan, S. L., Jotani, M. M. & Tiekink, E. R. T. (2019). Acta Cryst. E75, 308-318.]). As shown in the images of Fig. 3[link], the analysis reveals there are several red spots of variable intensity observed on the dnorm maps calculated for 4LH2 and 3-ClBA. These are indicative of close contact distances shorter than the van der Waals radii (Spackman & Jayatilaka, 2009[Spackman, M. A. & Jayatilaka, D. (2009). CrystEngComm, 11, 19-32.]). Specifically, red spots with intensity in decreasing order are observed for hydroxyl-O3—H3O⋯N1(pyrid­yl), amide-N2—H2N⋯O2(carbon­yl), pyr­id­yl-C1—H1⋯O1(amide), benzene-C14—H14⋯O1(amide), benzene-C12—H12⋯O1(amide) and methyl­ene-C6—H6A⋯O3(hydrox­yl); the dnorm distances for these short contacts are given in Table 2[link]. While the identified close contacts are consistent with those obtained from PLATON analysis (Spek, 2020[Spek, A. L. (2020). Acta Cryst. E76, 1-11.]), additional red spots are noted for pyridyl-C4—H4⋯C11(benzene) as well as benzyl-C10⋯C10(benzene), albeit with relatively weaker intensity than the other inter­actions mentioned above. As for the C13–Cl1⋯π(N1,C1–C5) contact, Table 2[link], the Hirshfeld surface analysis reveals only a faint-blue spot around the tip of Cl1 in Fig. 3[link](b) indicating the contact distance that is slightly less than the sum of the van der Waals radii (Spackman & Jayatilaka, 2009[Spackman, M. A. & Jayatilaka, D. (2009). CrystEngComm, 11, 19-32.]).

Table 2
A summary of short inter­atomic contacts (Å) for (I)a

Contact Distance Symmetry operation
H2N⋯O2b 1.95 1 − x, 2 − y, 1 − z
H3O⋯N1b 1.60 1 − x, 2 − y, 1 − z
H1⋯O1 2.27 −1 + x, −1 + y, 1 + z
H6A⋯O3 2.42 −1 + x, −1 + y, 1 + z
H12⋯O1 2.34 1 − x, 1 − y, 1 − z
H14⋯O1 2.25 x, y, z
H4⋯C11 2.66 1 − x, 1 − y, 1 − z
C10⋯C10 3.28 2 − x, 2 − y, 1 − z
Notes: (a) The inter­atomic distances are calculated in Crystal Explorer 17 (Turner et al., 2017[Turner, M. J., Mckinnon, J. J., Wolff, S. K., Grimwood, D. J., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). Crystal Explorer 17. The University of Western Australia.]) whereby the X—H bond lengths are adjusted to their neutron values; (b) these inter­actions correspond to conventional hydrogen bonds.
[Figure 3]
Figure 3
The dnorm maps plotted within the range of −0.2015 to 1.0590 arbitrary units for (a) 4LH2 and (b) 3-ClBA, showing O—H⋯N (yellow dashed lines), (N,C)—H⋯O (green dashed lines), C—H⋯C (blue dashed lines) and C⋯C (light-purple dashed lines) close contacts as indicated by the corresponding red spots of varying intensity.

To verify the nature of the Cl⋯π contact in (I)[link], the co-formers were subjected to electrostatic potential mapping through DFT-B3LYP/6-31G(d,p), as available in CrystalExplorer17. The analysis indicates that the Cl⋯π inter­action is weak in nature as evidenced from the white spot around the σ-hole region about the Cl1 atom in Fig. 4[link](a) as well as the faint-red spot around the centre of the π-ring centre, Fig. 4[link](b). A detailed study on the localized electrostatic charges shows that the σ-hole of Cl1 is about −0.0072 a.u. while the pyridyl π-hole is about −0.1270 a.u. indicating that the inter­action is rather dispersive in nature. This observation is in contrast with other charge complementary inter­actions as shown from the intense blue (i.e. electropositive) and red (i.e. electronegative) regions on the electrostatic surface map. For instance, the amide-N2—H2N⋯O2(carbon­yl) hydrogen bond has a point-to-point electrostatic charge of 0.1438 a.u. for H2N and −0.0622 a.u. for O2, suggestive of a strong inter­action, while benzene-C14—H14⋯O1(amide) shows complementary charges of 0.0427 and −0.0486 a.u. for H14 and O1, respectively, being indicative of a relatively weaker inter­action. Among all the identified close contacts, hydroxyl-O3—H3O⋯N1(pyrid­yl) is considered to be the strongest exhibiting a marked difference in the electrostatic charge of 0.2919 a.u. for H3O and −0.0727 a.u. for N1.

[Figure 4]
Figure 4
The electrostatic potential mapped onto the Hirshfeld surfaces within the isosurface value of −0.0481 to 0.0854 atomic units for (a) 3-ClBA and (b) 4LH2. The circles highlight the inter­action between the Cl1 atom, through the σ-hole region, and π-hole of the pyridyl ring.

The three-mol­ecule-aggregate of (I)[link] as well as its individual co-formers, i.e. 4LH2 and 3-ClBA, were subjected to fingerprint analysis for qu­anti­fication of the close contacts for each entity, Fig. 5[link](a). Overall (I)[link] exhibits a paw-like fingerprint profile which can be delineated into H⋯H (28.5%), H⋯O/O⋯H (23.2%), H⋯C/C⋯H (23.3%), H⋯N/N⋯H (2.2%), H⋯Cl/Cl⋯H (10.0%) and C⋯Cl/C⋯Cl (6.2%), as illustrated in Fig. 5[link](b)–(f); others contacts amount to 6.6%, constituting contacts less than 2.0% each. Among those contacts for (I)[link], only H⋯O/O⋯H and H⋯C/C⋯H exhibit minimum di + de contact distances tipped at ca 1.94 and 2.08 Å, respectively, significantly less than their respective sums of van der Waals radii of 2.61 and 2.79 Å; the remaining contacts occur at distances greater than their corresponding sums of van der Waals radii.

[Figure 5]
Figure 5
(a) The overall two-dimensional fingerprint plots for (I)[link], 4LH2 and 3-ClBA, and those delineated into (b) H⋯O/O⋯H, (c) H⋯C/C⋯H, (d) H⋯N/N⋯H, (e) H⋯Cl/Cl⋯H and (f) C⋯Cl contacts, with the percentage contributions specified within each plot.

A similar paw-like fingerprint profile is observed for the overall fingerprint plots of the individual 4LH2 and 3-ClBA mol­ecules. The key difference between these and that for (I)[link] is the asymmetry in the distributions owing to the inter­dependency of the inter­molecular inter­actions between the two co-formers. For 4LH2, the major contacts comprise H⋯H (34.5%), H⋯O/O⋯H (22.1%), H⋯C/C⋯H (20.3%), H⋯N/N⋯H (8.4%), H⋯Cl/Cl⋯H (6.4%) and C⋯Cl (5.0%). A detailed analysis on the corresponding contacts reveals that the (inter­nal)-H⋯O-(external) and (inter­nal)-H⋯C-(external) contacts are slightly more dominant over the (inter­nal)-O⋯H-(external) and (inter­nal)-C⋯H-(external) counterparts with the distribution of the contacts being 12.7 and 11.2% versus 9.4 and 9.1%, while the opposite is true for the (inter­nal)-H⋯N-(external) contact with a distribution of 0.6% as compared to 7.8% for (inter­nal)-N⋯H-(external). The stark difference in the dominance for H⋯N/N⋯H is likely due to the amide-H forming a hydrogen bond to O(carbon­yl) rather than to a nitro­gen acceptor. Among the major contacts, (inter­nal)-H⋯O-(external) and (inter­nal)-N⋯H-(external) display minimum di + de distances of about 1.94 and 1.60 Å, respectively, which are significantly shorter than the sums of the respective van der Waals radii as compared to the (inter­nal)-O⋯H-(external) and (inter­nal)-H⋯N-(external) counterparts of 2.24 and 3.62 Å, respectively. A similar observation is noted for (inter­nal)-H⋯C-(external) (∼2.66 Å) despite the deviation from the sum of the van der Waals radii (2.79 Å) being less significant.

As for the individual 3-ClBA mol­ecule, the major contacts in the overall fingerprint plot can be delineated into H⋯O/O⋯H (23.5%), H⋯C/C⋯H (22.9%), H⋯H (21.8%), H⋯Cl/Cl⋯H (11.9%), C⋯Cl/Cl⋯C (6.5%) and H⋯N/N⋯H (4.6%). The trend of dominance is more inclined towards (inter­nal)-XY-(external) for some close contacts (X = O, C and Cl; Y = H and C), with the distribution being 15.0, 14.4, 10.5 and 5.5% for O⋯H, C⋯H, Cl⋯H and Cl⋯C, respectively, compared to 8.5, 8.5, 1.4 and 1.0% for the corresponding H⋯O, H⋯C, H⋯Cl and C⋯Cl counterparts. In term of di + de contact distances, the key values are reciprocal to those for 4LH2 owing to the inter­dependency of inter­actions as mentioned previously.

5. Computational chemistry

The calculation of the inter­action energy for all pairwise mol­ecules in (I)[link] was performed through CrystalExplorer17 (Turner et al., 2017[Turner, M. J., Mckinnon, J. J., Wolff, S. K., Grimwood, D. J., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). Crystal Explorer 17. The University of Western Australia.]) following reported procedures (Tan, Jotani et al., 2019[Tan, S. L., Jotani, M. M. & Tiekink, E. R. T. (2019). Acta Cryst. E75, 308-318.]) with the purpose of studying the strength of each inter­action identified from the Hirshfeld surface analysis. The results tabulated in Table 3[link] show that the carb­oxy­lic acid-O3—H3O⋯N1(pyrid­yl) hydrogen bond has the greatest inter­action energy (Eint) with the value being −48.0 kJ mol−1, and this is followed by the dimeric amide-N2—H2N⋯O2(carbon­yl), benzene-C14—H14⋯O1(amide) and Cl1⋯π(N1,C1–C5) inter­actions, with a combined Eint of −38.7 kJ mol−1, the 16-membered {⋯OCNC3CH⋯} heterosynthon involving pyridyl-C1—H1⋯O1(amide) inter­actions (−24.6 kJ mol−1), benzene-C12—H12⋯O1(amide) and pyridyl-C4—H4⋯C11(benzene) with a combined Eint of −24.0 kJ mol−1, methyl­ene-C6—H6A⋯O3(hydrox­yl) (−15.8 kJ mol−1) as well as the benzene-C10⋯C10(benzene) inter­action with (−15.0 kJ mol−1). Inter­estingly, the strongest hydroxyl-O3—H3O⋯N1(pyrid­yl) inter­action in this crystal has an Eint value that is only slightly less than that of −49.4 and −52.0 kJ mol−1) (two independent mol­ecules) displayed by an equivalent O—H⋯N hydrogen bond complemented by a supporting pyridyl-C—H⋯O(carbon­yl) inter­action in the isomeric 2:1 co-crystal of 4LH2 with 4-ClBA (Tan & Tiekink, 2020b[Tan, S. L. & Tiekink, E. R. T. (2020b). Acta Cryst. E76, 245-253.]); the supporting C—H⋯O(carbon­yl) contact is absent in (I)[link].

Table 3
A summary of inter­action energies (kJ mol−1) calculated for (I)

Contact Eele Epol Edis Erep Etot Symmetry operation
N2—H2N⋯O2 +            
C14—H14⋯O1 +            
Cl1⋯π(N1,C1–C5) −39.1 −6.6 −21.6 28.7 −38.7 1 − x, 1 − y, 1 − z
O3—H3O⋯N1 −102.5 −17.5 −10.2 82.2 −48.0 −1 + x, y, z
C1—H1⋯O1 (×2) −22.0 −3.4 −16.1 16.9 −24.6 2 − x, 1 − y, −z
C6—H6A⋯O3 −7.7 −0.9 −18.3 11.2 −15.8 x, y, z
C12—H12⋯O1+            
C4—H4⋯C11 −12.9 −1.6 −31.0 21.6 −24.0 1 + x, 1 + y, 1 + z
C10⋯C10 −2.4 −0.4 −26.0 13.7 −15.0 2 − x, 2 − y, 1 − z

The co-crystal system is governed by a combination of electrostatic and dispersion forces leading to a three-dimensional wire mesh-like energy framework as shown in Fig. 6[link]. In the electrostatic energy framework, the hydroxyl-O3—H3O⋯N1(pyrid­yl) inter­action is the main foundation of the framework as evidenced from the thick cylindrical rods with other, relatively, thinner rods which ramify owing to various other O⋯H inter­actions, Fig. 6[link](a). The O⋯H inter­actions together with other complementary inter­actions are found to contribute to the dispersion energy framework which forms a similar topology as the electrostatic energy framework, Fig. 6[link](b). The combination of the other electrostatic and dispersion forces supersedes the strong inter­action energy from the hydroxyl-O3—H3O⋯N1(pyrid­yl) hydrogen bonding and leads to the overall energy framework illustrated in Fig. 6[link](c) without dominant inter­actions in a given direction. It is inter­esting to note that despite being an isomeric analogue to the 4LH2·2(4-ClBA) co-crystal (Tan & Tiekink, 2020b[Tan, S. L. & Tiekink, E. R. T. (2020b). Acta Cryst. E76, 245-253.]), (I)[link] exhibits completely different topological frameworks as compared to the ladder-like frameworks of 4LH2·2(4-ClBA).

[Figure 6]
Figure 6
Perspective views of the energy frameworks of (I)[link], showing the (a) electrostatic force, (b) dispersion force and (c) total energy. The radius of the cylinders is proportional to the relative strength of the corresponding energies, and they were adjusted to the same scale factor of 100 with a cut-off value of 8 kJ mol−1 within 2 × 2 × 2 unit cells.

6. Database survey

The aforementioned analogue of (I)[link], 4LH2·2(4-ClBA) (Tan & Tiekink, 2020b[Tan, S. L. & Tiekink, E. R. T. (2020b). Acta Cryst. E76, 245-253.]), is the most closely related, and indeed, isomeric co-crystal available for comparison; this too has been subjected to a detailed analysis of the mol­ecular packing. Co-crystals (I)[link] and (II) are not isostructural, with the asymmetric unit of (II) comprising two half-mol­ecules of 4LH2, i.e. 4LH2-IIa and 4LH2-IIb, as each is disposed about a centre of inversion, and two symmetry-independent mol­ecules of 4-ClBA, i.e. 4-ClBA-IIa and 4-ClBA-IIb. The common feature of the mol­ecular packing of (I)[link] and (II) is the formation of two three-mol­ecule aggregates. The key difference in the mol­ecular packing relates to the nature of the supra­molecular tapes: in (II), the tapes are sustained by a sequence of ten-membered {⋯HNCCO}2 synthons, as highlighted in Fig. 7[link].

[Figure 7]
Figure 7
A comparison of the mol­ecular packing in (I)[link] (red) and (II) (blue), showing the differences in the mol­ecular connectivities surrounding the central 4LH2 mol­ecule.

A comparison of the percentage contributions by the most prominent contacts to the respective Hirshfeld surfaces of (I)[link] and (II), and including their individual components has been made (Jotani et al., 2019[Jotani, M. M., Wardell, J. L. & Tiekink, E. R. T. (2019). Z. Kristallogr. Cryst. Mater. 234, 43-57.]). The results are summarized in Fig. 8[link] and suggest that to a first approximation there are no dramatic variations between the contacts made to the Hirshfeld surfaces calculated for (I)[link] and (II). Among the noticeable differences are due to the H⋯O/O⋯H contacts which are greater for 3-ClBA, by 5.8 and 5.6%, respectively than for 4-ClBA-IIa and IIb. This is compensated by a reduction in the H⋯Cl/Cl⋯H contacts by 4.9 and 5.6%. One possible reason for the increase in O⋯H/H⋯O contacts in (I)[link] cf. (II) relates to the participation of the carbonyl-O atom in formal hydrogen bonding to the amide-N—H group and the prominent role of the amide-O1 atom in providing points of contact between mol­ecules.

[Figure 8]
Figure 8
A comparison of the percentage contributions of the various contacts to the calculated Hirshfeld surfaces for (a) 4LH2-I, (b) 4LH2-IIa, (c) 4LH2-IIb, (d) 3-ClBA-I, (e) 4-ClBA-IIa, (f) 4-ClBA-IIb, (g) (I)[link], (h) (IIa) and (i) (IIb).

7. Synthesis and crystallization

The precursor, N,N′-bis­[(pyridin-4-yl)meth­yl]oxalamide (4LH2) was prepared according to a literature procedure: M.p. 486.3–487.6 K; lit. 486–487 K (Nguyen et al., 1998[Luong Nguyen, T., Scott, A., Dinkelmeyer, B., Fowler, F. W. & Lauher, J. W. (1998). New J. Chem. 22, 129-135.]). 3-Chloro­benzoic acid (Merck; 3-ClBA) was of reagent grade and used as received without further purification. The co-former 4LH2 (0.271 g, 0.001 mol) was mixed with 3-ClBA (0.157 g, 0.001 mol) and the mixture was then ground for 15 min in the presence of a few drops of methanol. The procedure was repeated twice. Colourless blocks were obtained through careful layering of toluene (1 ml) on an N,N-di­methyl­formamide solution (1 ml) of the ground mixture. M.p. 436.6–437.7 K. IR (cm−1): 3280 ν(N—H), 3070–2919 ν(C—H), 1703–1656 ν(C=O), 1524 ν(C=C), 1415 ν(C—N), 753 ν(C—Cl).

8. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 4[link]. The carbon-bound H atoms were placed in calculated positions (C—H = 0.95–0.99 Å) and were included in the refinement in the riding-model approximation, with Uiso(H) set to 1.2Ueq(C). The oxygen- and nitro­gen-bound H atoms were located from a difference-Fourier map and refined with O—H = 0.84±0.01 Å and N—H = 0.86±0.01 Å, respectively, and with Uiso(H) set to 1.5Ueq(O) or 1.2Ueq(N).

Table 4
Experimental details

Crystal data
Chemical formula C7H5ClO2·C7H7N2O
Mr 291.71
Crystal system, space group Triclinic, P[\overline{1}]
Temperature (K) 100
a, b, c (Å) 7.7817 (2), 9.5743 (3), 11.1516 (4)
α, β, γ (°) 113.721 (3), 90.064 (2), 112.397 (3)
V3) 691.47 (4)
Z 2
Radiation type Cu Kα
μ (mm−1) 2.54
Crystal size (mm) 0.17 × 0.07 × 0.06
 
Data collection
Diffractometer XtaLAB Synergy, Dualflex, AtlasS2
Absorption correction Gaussian (CrysAlis PRO; Rigaku OD, 2018[Rigaku OD (2018). CrysAlis PRO. Rigaku Corporation, Oxford, England.])
Tmin, Tmax 0.604, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 17474, 2873, 2589
Rint 0.043
(sin θ/λ)max−1) 0.631
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.128, 1.07
No. of reflections 2873
No. of parameters 189
No. of restraints 2
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.61, −0.47
Computer programs: CrysAlis PRO (Rigaku OD, 2018[Rigaku OD (2018). CrysAlis PRO. Rigaku Corporation, Oxford, England.]), SHELXS (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2017/1 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Computing details top

Data collection: CrysAlis PRO (Rigaku OD, 2018); cell refinement: CrysAlis PRO (Rigaku OD, 2018); data reduction: CrysAlis PRO (Rigaku OD, 2018); program(s) used to solve structure: SHELXS (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2017/1 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012), DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

N,N'-Bis[(pyridin-4-yl)methyl]ethanediamide–3-chlorobenzoic acid (1/1) top
Crystal data top
C7H5ClO2·C7H7N2OZ = 2
Mr = 291.71F(000) = 302
Triclinic, P1Dx = 1.401 Mg m3
a = 7.7817 (2) ÅCu Kα radiation, λ = 1.54184 Å
b = 9.5743 (3) ÅCell parameters from 7027 reflections
c = 11.1516 (4) Åθ = 5.4–76.0°
α = 113.721 (3)°µ = 2.54 mm1
β = 90.064 (2)°T = 100 K
γ = 112.397 (3)°Rhombohedral, colourless
V = 691.47 (4) Å30.17 × 0.07 × 0.06 mm
Data collection top
XtaLAB Synergy, Dualflex, AtlasS2
diffractometer
2873 independent reflections
Radiation source: micro-focus sealed X-ray tube, PhotonJet (Cu) X-ray Source2589 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.043
Detector resolution: 5.2558 pixels mm-1θmax = 76.6°, θmin = 4.4°
ω scansh = 99
Absorption correction: gaussian
(CrysAlisPro; Rigaku OD, 2018)
k = 1212
Tmin = 0.604, Tmax = 1.000l = 1313
17474 measured reflections
Refinement top
Refinement on F2Primary atom site location: dual
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.047H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.128 w = 1/[σ2(Fo2) + (0.0629P)2 + 0.363P]
where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max < 0.001
2873 reflectionsΔρmax = 0.61 e Å3
189 parametersΔρmin = 0.47 e Å3
2 restraints
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl11.16272 (7)1.19147 (7)0.97323 (5)0.04950 (19)
O20.52027 (18)0.7929 (2)0.61549 (14)0.0462 (4)
O30.61166 (18)0.70870 (18)0.41896 (13)0.0379 (3)
H3O0.4966 (19)0.676 (4)0.389 (3)0.080 (10)*
C80.6450 (2)0.7875 (2)0.54909 (18)0.0323 (4)
C90.8502 (2)0.8715 (2)0.61122 (18)0.0314 (4)
C100.9858 (3)0.8450 (2)0.5341 (2)0.0337 (4)
H100.9491120.7741820.4411160.040*
C111.1744 (3)0.9230 (3)0.5943 (2)0.0383 (4)
H111.2664230.9031270.5421800.046*
C121.2306 (3)1.0291 (3)0.7289 (2)0.0385 (4)
H121.3601501.0825950.7695800.046*
C131.0942 (3)1.0560 (2)0.8034 (2)0.0358 (4)
C140.9041 (2)0.9776 (2)0.74687 (19)0.0341 (4)
H140.8122840.9960770.7997700.041*
O10.62312 (17)0.12645 (16)0.07710 (13)0.0330 (3)
N11.2621 (2)0.5924 (2)0.31316 (17)0.0383 (4)
N20.5685 (2)0.2032 (2)0.13447 (16)0.0328 (3)
H2N0.522 (3)0.167 (3)0.1913 (19)0.045 (7)*
C11.1930 (3)0.6341 (3)0.22886 (19)0.0388 (4)
H11.2789030.7126660.2018890.047*
C21.0017 (3)0.5676 (2)0.17938 (19)0.0365 (4)
H20.9580870.6005060.1199780.044*
C30.8745 (3)0.4522 (2)0.21761 (18)0.0339 (4)
C40.9465 (3)0.4093 (3)0.3046 (2)0.0444 (5)
H40.8639620.3303190.3326150.053*
C51.1384 (3)0.4818 (3)0.3502 (2)0.0459 (5)
H51.1852520.4520590.4107110.055*
C60.6630 (3)0.3820 (2)0.1718 (2)0.0381 (4)
H6A0.6082780.4419560.2444260.046*
H6B0.6395550.4026020.0945030.046*
C70.5558 (2)0.0917 (2)0.01203 (17)0.0291 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0348 (3)0.0602 (3)0.0397 (3)0.0143 (2)0.0083 (2)0.0140 (2)
O20.0246 (6)0.0723 (10)0.0315 (7)0.0152 (6)0.0036 (5)0.0177 (7)
O30.0292 (7)0.0445 (8)0.0298 (7)0.0093 (6)0.0013 (5)0.0124 (6)
C80.0287 (9)0.0384 (9)0.0297 (9)0.0112 (7)0.0039 (7)0.0173 (8)
C90.0262 (8)0.0363 (9)0.0333 (9)0.0109 (7)0.0041 (7)0.0187 (8)
C100.0323 (9)0.0355 (9)0.0369 (10)0.0145 (7)0.0081 (8)0.0189 (8)
C110.0286 (9)0.0456 (11)0.0496 (12)0.0176 (8)0.0127 (8)0.0269 (10)
C120.0241 (8)0.0452 (10)0.0515 (12)0.0113 (7)0.0023 (8)0.0289 (10)
C130.0286 (9)0.0414 (10)0.0371 (10)0.0114 (7)0.0005 (7)0.0199 (8)
C140.0259 (8)0.0426 (10)0.0354 (10)0.0132 (7)0.0043 (7)0.0194 (8)
O10.0242 (6)0.0417 (7)0.0306 (7)0.0080 (5)0.0035 (5)0.0186 (6)
N10.0319 (8)0.0360 (8)0.0355 (9)0.0028 (6)0.0022 (6)0.0155 (7)
N20.0246 (7)0.0362 (8)0.0278 (8)0.0053 (6)0.0000 (6)0.0117 (6)
C10.0372 (10)0.0420 (10)0.0309 (9)0.0058 (8)0.0040 (8)0.0199 (8)
C20.0387 (10)0.0393 (10)0.0290 (9)0.0107 (8)0.0017 (7)0.0177 (8)
C30.0320 (9)0.0301 (9)0.0284 (9)0.0057 (7)0.0022 (7)0.0091 (7)
C40.0342 (10)0.0393 (10)0.0503 (12)0.0023 (8)0.0080 (9)0.0273 (10)
C50.0380 (11)0.0423 (11)0.0511 (13)0.0019 (8)0.0099 (9)0.0284 (10)
C60.0318 (9)0.0365 (10)0.0366 (10)0.0095 (8)0.0019 (8)0.0117 (8)
C70.0169 (7)0.0381 (9)0.0279 (8)0.0069 (7)0.0012 (6)0.0146 (7)
Geometric parameters (Å, º) top
Cl1—C131.746 (2)N1—C51.340 (3)
O2—C81.225 (2)N2—H2N0.857 (10)
O3—H3O0.846 (10)N2—C61.453 (2)
O3—C81.308 (2)N2—C71.326 (2)
C8—C91.499 (2)C1—H10.9500
C9—C101.395 (3)C1—C21.385 (3)
C9—C141.391 (3)C2—H20.9500
C10—H100.9500C2—C31.389 (3)
C10—C111.386 (3)C3—C41.385 (3)
C11—H110.9500C3—C61.517 (3)
C11—C121.382 (3)C4—H40.9500
C12—H120.9500C4—C51.376 (3)
C12—C131.386 (3)C5—H50.9500
C13—C141.386 (3)C6—H6A0.9900
C14—H140.9500C6—H6B0.9900
O1—C71.228 (2)C7—C7i1.539 (3)
N1—C11.340 (3)
C8—O3—H3O110 (2)C7—N2—C6120.72 (16)
O2—C8—O3123.38 (17)N1—C1—H1118.6
O2—C8—C9122.38 (17)N1—C1—C2122.84 (17)
O3—C8—C9114.23 (15)C2—C1—H1118.6
C10—C9—C8120.62 (17)C1—C2—H2120.4
C14—C9—C8119.03 (16)C1—C2—C3119.22 (18)
C14—C9—C10120.35 (17)C3—C2—H2120.4
C9—C10—H10120.3C2—C3—C6121.38 (18)
C11—C10—C9119.44 (19)C4—C3—C2117.76 (17)
C11—C10—H10120.3C4—C3—C6120.78 (17)
C10—C11—H11119.5C3—C4—H4120.2
C12—C11—C10121.04 (18)C5—C4—C3119.60 (18)
C12—C11—H11119.5C5—C4—H4120.2
C11—C12—H12120.7N1—C5—C4122.98 (19)
C11—C12—C13118.63 (17)N1—C5—H5118.5
C13—C12—H12120.7C4—C5—H5118.5
C12—C13—Cl1119.31 (15)N2—C6—C3112.60 (16)
C14—C13—Cl1118.88 (15)N2—C6—H6A109.1
C14—C13—C12121.81 (19)N2—C6—H6B109.1
C9—C14—H14120.6C3—C6—H6A109.1
C13—C14—C9118.72 (18)C3—C6—H6B109.1
C13—C14—H14120.6H6A—C6—H6B107.8
C5—N1—C1117.60 (17)O1—C7—N2124.94 (17)
C6—N2—H2N120.9 (16)O1—C7—C7i121.2 (2)
C7—N2—H2N118.3 (16)N2—C7—C7i113.87 (19)
Cl1—C13—C14—C9179.18 (14)N1—C1—C2—C30.2 (3)
O2—C8—C9—C10171.79 (19)C1—N1—C5—C40.7 (3)
O2—C8—C9—C148.8 (3)C1—C2—C3—C40.1 (3)
O3—C8—C9—C108.1 (2)C1—C2—C3—C6176.96 (19)
O3—C8—C9—C14171.32 (17)C2—C3—C4—C50.4 (3)
C8—C9—C10—C11179.40 (17)C2—C3—C6—N2138.48 (19)
C8—C9—C14—C13179.43 (17)C3—C4—C5—N10.8 (4)
C9—C10—C11—C121.3 (3)C4—C3—C6—N244.8 (3)
C10—C9—C14—C130.0 (3)C5—N1—C1—C20.2 (3)
C10—C11—C12—C130.3 (3)C6—N2—C7—O11.8 (3)
C11—C12—C13—Cl1179.29 (15)C6—N2—C7—C7i177.61 (17)
C11—C12—C13—C141.0 (3)C6—C3—C4—C5176.5 (2)
C12—C13—C14—C91.1 (3)C7—N2—C6—C386.3 (2)
C14—C9—C10—C111.2 (3)
Symmetry code: (i) x+1, y, z.
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the (N1,C1–C5) ring.
D—H···AD—HH···AD···AD—H···A
N2—H2N···O1i0.86 (2)2.34 (3)2.717 (2)107 (2)
N2—H2N···O2ii0.86 (2)2.08 (2)2.863 (2)151 (2)
O3—H3O···N1iii0.84 (2)1.74 (2)2.581 (2)174 (4)
C14—H14···O1iv0.952.373.286 (2)161
C1—H1···O1v0.952.393.286 (3)157
C12—H12···O1vi0.952.463.328 (3)152
C6—H6A···O30.992.503.400 (3)151
C13—Cl1···Cg11.75 (1)3.83 (1)5.358 (2)145 (1)
Symmetry codes: (i) x+1, y, z; (ii) x+1, y+1, z+1; (iii) x1, y, z; (iv) x, y+1, z+1; (v) x+2, y+1, z; (vi) x+1, y+1, z+1.
A summary of short interatomic contacts (Å) for (I)a top
ContactDistanceSymmetry operation
H2N···O2b1.951 - x, 2 - y, 1 - z
H3O···N1b1.601 - x, 2 - y, 1 - z
H1···O12.27-1 + x, -1 + y, 1 + z
H6A···O32.42-1 + x, -1 + y, 1 + z
H12···O12.341 - x, 1 - y, 1 - z
H14···O12.25x, y, z
H4···C112.661 - x, 1 - y, 1 - z
C10···C103.282 - x, 2 - y, 1 - z
Notes: (a) The interatomic distances are calculated in Crystal Explorer 17 (Turner et al., 2017) whereby the X—H bond lengths are adjusted to their neutron values; (b) these interactions correspond to conventional hydrogen bonds.
A summary of interaction energies (kJ mol-1) calculated for (I) top
ContactEeleEpolEdisErepEtotSymmetry operation
N2—H2N···O2 +
C14—H14···O1 +
Cl1···π(N1,C1–C5)-39.1-6.6-21.628.7-38.71 - x, 1 - y, 1 - z
O3—H3O···N1-102.5-17.5-10.282.2-48.0-1 + x, y, z
C1—H1···O1 (×2)-22.0-3.4-16.116.9-24.62 - x, 1 - y, -z
C6—H6A···O3-7.7-0.9-18.311.2-15.8x, y, z
C12—H12···O1+
C4—H4···C11-12.9-1.6-31.021.6-24.01 + x, 1 + y, 1 + z
C10···C10-2.4-0.4-26.013.7-15.02 - x, 2 - y, 1 - z
 

Funding information

Crystallographic research at Sunway University is supported by Sunway University Sdn Bhd (grant No. STR-RCTR-RCCM-001-2019).

References

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