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Crystal structure, Hirshfeld surface analysis and computational study of bis­­(2-{[(2,6-di­chloro­benzyl­­idene)hydrazinyl­­idene]meth­yl}phenolato)cobalt(II) and of the copper(II) analogue

aChemical Research Laboratory, Department of Chemistry, Saurashtra University, Rajkot, Gujarat 360005, India, bDepartment of Physics, Bhavan's Sheth R. A. College of Science, Ahmedabad, Gujarat 380001, India, and cResearch 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 W. T. A. Harrison, University of Aberdeen, Scotland (Received 6 December 2019; accepted 7 December 2019; online 1 January 2020)

The title homoleptic Schiff base complexes, [M(C14H9Cl2N2O)2], for M = CoII, (I), and CuII, (II), present distinct coordination geometries despite the Schiff base dianion coordinating via the phenolato-O and imine-N atoms in each case. For (I), the coordination geometry is based on a trigonal bipyramid whereas for (II), a square-planar geometry is found (Cu site symmetry [\overline{1}]). In the crystal of (I), discernible supra­molecular layers in the ac plane are sustained by chloro­benzene-C—H⋯O(coordinated), chloro­benzene-C—H⋯π(fused-benzene ring) as well as π(fused-benzene, chloro­benzene)–π(chloro­benzene) inter­actions [inter-centroid separations = 3.6460 (17) and 3.6580 (16) Å, respectively]. The layers inter-digitate along the b-axis direction and are linked by di­chloro­benzene-C—H⋯π(fused-benzene ring) and ππ inter­actions between fused-benzene rings and between chloro­benzene rings [inter-centroid separations = 3.6916 (16) and 3.7968 (19) Å, respectively] . Flat, supra­molecular layers are also found in the crystal of (II), being stabilized by ππ inter­actions formed between fused-benzene rings and between chloro­benzene rings [inter-centroid separations = 3.8889 (15) and 3.8889 (15) Å, respectively]; these stack parallel to [10[\overline{1}]] without directional inter­actions between them. The analysis of the respective calculated Hirshfeld surfaces indicate diminished roles for H⋯H contacts [26.2% (I) and 30.5% (II)] owing to significant contributions by Cl⋯H/H⋯Cl contacts [25.8% (I) and 24.9% (II)]. Minor contributions by Cl⋯Cl [2.2%] and Cu⋯Cl [1.9%] contacts are indicated in the crystals of (I) and (II), respectively. The inter­action energies largely arise from dispersion terms; the aforementioned Cu⋯Cl contact in (II) gives rise to the most stabilizing inter­action in the crystal of (II).

1. Chemical context

Schiff base mol­ecules are well-known ligands because of the ease of their formation and for their rich coordination chemistry with a wide range of metal ions. A prominent application of metal–Schiff base complexes is as catalysts in different chemical reactions (Patti et al., 2009[Patti, A., Pedotti, S., Ballistreri, F. P. & Sfrazzetto, G. T. (2009). Molecules, 14, 4312-4325.]). The Schiff base mol­ecules themselves are of considerable inter­est as they display a broad range of biological activities such as anti-bacterial, anti-fungal, anti-viral, anti-malarial, anti-inflammatory, etc. (Guo et al., 2007[Guo, Z., Xing, R., Liu, S., Zhong, Z., Ji, X., Wang, L. & Li, P. (2007). Carbohydr. Res. 342, 1329-1332.]; Przybylski et al., 2009[Przybylski, P., Huczynski, A., Pyta, K., Brzezinski, B. & Bartl, F. (2009). Curr. Org. Chem. 13, 124-148.]; Annapoorani & Krishnan, 2013[Annapoorani, S. & Krishnan, C. (2013). J. Chem. Tech. Res. 5, 180-185.]). A full range of metal complexes formed with these usually multidentate ligands often result in species with enhanced biological action (Bagihalli et al., 2008[Bagihalli, G. B., Avaji, P. G., Patil, S. A. & Badami, P. S. (2008). Eur. J. Med. Chem. 43, 2639-2649.]; Tian et al., 2009[Tian, B., He, M., Tang, S., Hewlett, I., Tan, Z., Li, J., Jin, Y. & Yang, M. (2009). Bioorg. Med. Chem. Lett. 19, 2162-2167.], 2011[Tian, B., He, M., Tan, Z., Tang, S., Hewlett, I., Chen, S., Jin, Y. & Yang, M. (2011). Chem. Biol. Drug Des. 77, 189-198.]; Chohan et al., 2001[Chohan, Z. H., Jaffery, M. F. & Supuran, C. T. (2001). Met.-Based Drugs, 8, 95-101.]). As part of our ongoing studies of Schiff base ligands and their metal complexes (Manawar, Gondaliya, Mamtora et al., 2019[Manawar, R. B., Gondaliya, M. B., Mamtora, M. J. & Shah, M. K. (2019). Sci. News 126, 222-247.]), the crystal and mol­ecular structures, Hirshfeld surface analysis and computational study of homoleptic CoII (I)[link] and CuII (II)[link] complexes derived from 2-{(1E)-[(E)-2-(2,6-di­chloro­benzyl­idene)hydra­zin-1-yl­idene]meth­yl}phenol (Manawar, Gondaliya, Shah et al., 2019[Manawar, R. B., Gondaliya, M. B., Shah, M. K., Jotani, M. M. & Tiekink, E. R. T. (2019). Acta Cryst. E75, 1423-1428.]) are described herein.

[Scheme 1]

2. Structural commentary

The cobalt complex (I)[link], Fig. 1[link], lacks crystallographic symmetry and the metal ion is N,O-coordinated by two mono-anionic Schiff base ligands; selected geometric parameters are collated in Table 1[link]. The N2O2 donor set defines an approximate tetra­hedron with the range of tetra­hedral angles being over 30°. Thus, the narrowest angle of 94.06 (7)° is found for O1—Co—N1 while the widest of 125.33 (8)° is noted for O1—Co—O2. A geometric measure of a four-coordinate geometry is the value of τ4, which has values of τ4 = 1.0 for an ideal tetra­hedron and τ4 = 0.0 for an ideal square-planar geometry (Yang et al., 2007[Yang, L., Powell, D. R. & Houser, R. P. (2007). Dalton Trans. pp. 955-964.]). In (I)[link], τ4 = 0.82, indicating a geometry close to trigonal pyramidal. Each of the Schiff base ligands forms a six-membered Co,O,C3,N chelate ring. These adopt an envelope conformation with the Co atom lying 0.253 (3) Å out of the least-squares plane defined by the five remaining atoms of the O1-chelate ring (r.m.s. deviation = 0.0086 Å); the equivalent values for the O2-chelate ring are 0.376 (3) and 0.0222 Å, respectively. The dihedral angle formed between the planar regions of the chelate rings is 86.44 (8)°, consistent with a near to orthogonal relationship. For the O1-chelate ring, the dihedral angle between the five co-planar atoms and the fused-benzene and pendent di­chloro­benzene rings are 0.92 (13) and 7.34 (14)°, respectively, and the dihedral angle between the benzene rings is 6.47 (15)°, indicating a small deviation from planarity. The equivalent dihedral angles for the O2-chelate ring are 1.99 (14), 7.25 (12) and 5.58 (12)°, respectively. These data are consistent with small twists about the N1—N2 [the C7—N1—N2—C8 torsion angle = 166.6 (2)°] and C16—C21 [C15—C16—C21—N3 = 6.4 (4)°] bonds. Finally, each Schiff base ligand features two imine bonds, with the bond length involving the coordinated N1 atom [1.304 (3) Å] being longer than the second N2-imine bond [1.251 (3) Å]; for the O2-ligand, C21—N3 = 1.303 (3) Å and C22—N4 = 1.247 (3) Å. The configurations about imine bonds are different with those involving the coordinated N1 and N3 atoms being Z, while the configurations about the other imine bonds are E.

Table 1
Selected geometric parameters (Å, °) for (I)[link] and (II)a

Parameter (I): M = CoII (II): M = CuII
M—O1 1.8940 (17) 1.8776 (14)
M—O2 1.8937 (17) 1.8776 (14)a
M—N1 1.9988 (19) 2.0211 (16)
M—N3 1.999 (2) 2.0211 (16)a
N1—N2 1.411 (3) 1.416 (2)
N3—N4 1.410 (3) 1.416 (2)a
C7—N1 1.304 (3) 1.294 (2)
C8—N2 1.251 (3) 1.258 (3)
C21—N3 1.303 (3) 1.294 (2)a
C22—N4 1.247 (3) 1.258 (3)a
     
O1—Co—O2 125.33 (8) 180a
O1—Co—N1 94.06 (7) 90.28 (6)
O1—Co—N3 112.12 (8) 89.72 (6)
O2—Co—N1 113.82 (8) 89.72 (6)a
O2—Co—N3 94.60 (8) 90.28 (6)a
N1—Co—N3 119.03 (8) 180a
Notes: (a) The CuII atom in (II)[link] lies on a centre of inversion so O2 is equivalent to O1, N3 to N1, etc. and are related by the symmetry operation 1 − x, 1 − y, 1 − z.
[Figure 1]
Figure 1
The mol­ecular structure of (I)[link] showing the atom-labelling scheme and displacement ellipsoids at the 35% probability level.

Recently, the crystal structure of the precursor Schiff base ligand became available (Manawar, Gondaliya, Shah et al., 2019[Manawar, R. B., Gondaliya, M. B., Shah, M. K., Jotani, M. M. & Tiekink, E. R. T. (2019). Acta Cryst. E75, 1423-1428.]). Here, each imine bond has an E-configuration and the bond lengths of the imine bonds, i.e. 1.281 (2) and 1.258 (3) Å, are inter­mediate to those noted in (I)[link]. A very similar conformation of the Schiff base ligand is found with a small twist about the central N—N bond [the C—N—N—C torsion angle = −172.7 (2)°]. The dihedral angles between the outer rings is 4.83 (13)°.

A distinct coordination geometry is found in the CuII complex, (II)[link], Fig. 2[link] and Table 1[link]. The CuII atom lies on a crystallographic centre of inversion. As for (I)[link], N,O-chelation is observed. From symmetry, the N2O2 donor set is strictly planar. The CuII atom lies 0.2582 (13) Å above the resultant square-plane. The chelate rings adopt an envelope conformation, as for (I)[link], with the Cu atom lying 0.470 (2) Å above the plane through the remaining atoms of the chelate ring (r.m.s. deviation = 0.0129 Å). The magnitude of the dihedral angle between the five co-planar atoms of the chelate ring and the fused-benzene ring [1.43 (13)°] resembles the situation in (I)[link], but that formed with pendent di­chloro­benzene ring is quite distinct, at 82.63 (8)°, consistent with an orthogonal relationship. This is reflected in the C7—N1—N2—C8 torsion angle of 141.33 (19)°. The different configuration arises to avoid steric hindrance within the square-planar environment. The Cu—O,N bond lengths span a wider range, i.e. 0.14 Å, c.f. 0.11 Å for the Co—O,N bond lengths in (II)[link], with the Cu—O bond lengths being shorter than the Co—O bonds, and the Cu—N bonds being longer than the Co—N bonds. Comparable trends are seen in the configurations of the imine bonds, Table 1[link].

[Figure 2]
Figure 2
The mol­ecular structure of (II)[link] showing the atom-labelling scheme and displacement ellipsoids at the 35% probability level. Unlabelled atoms are related by the symmetry operation 1 − x, 1 − y, 1 − z.

3. Supra­molecular features

The geometric parameters characterizing a number of the identified inter­molecular contacts in the crystal of (I)[link] are listed in Table 2[link]. Globally, the mol­ecular packing can be described as comprising inter-digitated layers stacked along the the b-axis direction. Thus, layers in the ac plane are consolidated by chloro­benzene-C—H⋯O(coordinated), chloro­benzene-C—H⋯π(fused-benzene ring) as well as π(fused-benzene, chloro­benzene)–π(chloro­benzene) inter­actions [Cg(C15–C20)⋯Cg(C23–C28) separation = 3.6460 (17) Å with angle of inclination = 5.57 (13)° for symmetry operation −1 + x, y, z and Cg(C23–C28)⋯Cg(C23–C28) = 3.6580 (16) Å with angle of inclination = 0° for symmetry operation 2 − x, 1 − y, 1 − z]; the specified ππ inter­actions involve rings derived from the O2-ligand only. A view of the supra­molecular layer is shown in Fig. 3[link](a). As highlighted in Fig. 3[link](b), the layers inter-digitate along the b-axis. The connections between layers are chloro­benzene-C—H⋯π(fused-benzene ring) as well as ππ inter­actions (involving rings of the O1-ligand only) between centrosymmetrically related fused-benzene rings [π(C1–C6)⋯π(C1–C6) = 3.6916 (16) Å for symmetry operation 1 − x, − y, 1 − z and π(chloro­benzene)–π(chloro­benzene) rings = 3.7968 (19) Å for symmetry operation 1 − x, − y, 2 − z].

Table 2
Hydrogen-bond geometry (Å, °) for (I)[link]

Cg3 is the centroid of the C1–C6 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C27—H27⋯O1i 0.93 2.35 3.114 (3) 140
C25—H25⋯Cg3ii 0.93 2.86 3.647 (3) 143
Symmetry codes: (i) x+1, y, z; (ii) -x+2, -y+1, -z+1.
[Figure 3]
Figure 3
Mol­ecular packing in the crystal of (I)[link]: (a) supra­molecular layer sustained by C—H⋯O, C—H⋯π and ππ inter­actions shown as orange, blue and purple dashed lines, respectively, and (b) a view of the unit-cell contents in a projection down the c axis.

The key feature of the mol­ecular packing in the crystal of (II)[link] is the formation of ππ inter­actions between centrosymmetrically related mol­ecules. To a first approximation, the mol­ecular packing resembles that of (I)[link] in that layers assemble into a three-dimensional architecture. As seen in Fig. 4[link](a), the layers are flat and are sustained by π(fused-benzene)–π(fused-benzene) [inter-centroid Cg(C1–C6)⋯Cg(C1—C6) separation = 3.8889 (15) Å for symmetry operation 1 − x, − y, 1 − z] and π(di­chloro­benzene)—π(di­chloro­benzene) [inter-centroid separation = Cg(C9–C14)⋯Cg(C9—C14) = 3.8889 (15) Å for symmetry operationx, 1 − y, − z] inter­actions. The layers lie parallel to (10[\overline{1}]) and stack without directional inter­actions between them. A view of the stacking of layers/unit-cell contents is shown in Fig. 4[link](b).

[Figure 4]
Figure 4
Mol­ecular packing in the crystal of (II)[link]: (a) supra­molecular layer sustained by ππ inter­actions shown as purple dashed lines and (b) a view of the unit-cell contents in a projection down the b axis.

4. Hirshfeld surface analysis

The Hirshfeld surfaces were calculated for each of (I)[link] and (II)[link] employing 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.]) and literature protocols (Tan et al., 2019[Tan, S. L., Jotani, M. M. & Tiekink, E. R. T. (2019). Acta Cryst. E75, 308-318.]). This study was undertaken in order to determine the influence of weak, non-covalent inter­actions upon the mol­ecular packing in the absence of conventional hydrogen bonding.

On the Hirshfeld surface mapped over dnorm for (I)[link] in Fig. 5[link](a) and (b), the bright-red spots near the H27 atom of the (C23–C28) ring and the coordinating O1 atom are an indication of the C—H⋯O inter­action. Referring to Table 3[link], the presence of short inter­atomic contacts involving the CoII, chloride and chloro­benzene-hydrogen atoms and the atoms of the C1–C6 benzene ring are characterized as faint-red spots near the respective atoms on the dnorm-mapped Hirshfeld surface. The blue bump near the H25 atom and the bright-orange spot about the C1–C6 ring on the Hirshfeld surface mapped with shape-index property in Fig. 5[link](c) correspond to the donor and acceptor of the C—H⋯π contact. The absence of strong, directional inter­actions in the crystal structure of (II)[link] is evident from its Hirshfeld surface mapped over dnorm in Fig. 6[link], as the surface contains only some tiny, diffuse red spots near the atoms corresponding to short inter­atomic Cl⋯H and C⋯C contacts listed in Table 4[link].

Table 3
Summary of short inter­atomic contacts (Å) in (I)[link] and (II)a

Contact Distance Symmetry operation
(I)    
Cl1⋯Cl3 3.4993 (13) x, −1 + y, z
Cl3⋯H7 2.70 x, 1 + y, z
Cl4⋯H3 2.74 2 − x, − y, 1 − z
C1⋯H26 2.71 2 − x, 1 − y, 1 − z
C6⋯H26 2.76 2 − x, 1 − y, 1 − z
Co⋯C27 3.558 (3) −1 + x, y, z
Co⋯H27 3.08 −1 + x, y, z
H5⋯H12 2.23 x, y, −1 + z
H5⋯H13 2.30 x, y, −1 + z
(II)    
Cl1⋯H7 2.81 1 − x, 1 − y, −z
C5⋯C7 3.378 (3) 1 − x, −y, 1 − z
Cu⋯Cl2 3.2858 (7) 1 + x, y, 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.

Table 4
Percentage contributions of inter­atomic contacts to the Hirshfeld surface for (I)[link] and (II)

Contact Percentage contribution
  (I) (II)
H⋯H 26.2 30.5
O⋯H/H⋯O 7.9 4.2
C⋯H/H⋯C 16.7 14.5
Cl⋯H/H⋯Cl 25.8 24.9
C⋯C 12.0 9.8
N⋯H/H⋯ N 5.5 6.2
Cl⋯Cl 2.2 0.4
C⋯O/O⋯C 0.5 0.3
C⋯N/N⋯C 0.5 1.3
Cl⋯O/O⋯Cl 0.2 0.4
C⋯Cl/Cl⋯C 1.9 3.9
Cl⋯N/N⋯Cl 0.2 1.6
M⋯H/H⋯M 0.4 0.1
M⋯Cl/Cl⋯M 0.0 1.9
[Figure 5]
Figure 5
View of the Hirshfeld surface for (I)[link] mapped (a) and (b) over dnorm in the range −0.123 to + 1.343 arbitrary units and (c) with the shape-index property highlighting inter­molecular C—H⋯π/π⋯H—C contacts.
[Figure 6]
Figure 6
A view of the Hirshfeld surface for (II)[link] mapped over dnorm in the range −0.016 to 1.528 arbitrary units.

On the Hirshfeld surfaces mapped over the electrostatic potential for (I)[link] in Fig. 7[link](a), the donors and acceptors of the C—H⋯O and C—H⋯π contacts (Table 3[link]) are viewed as blue and red regions near the respective atoms corresponding to positive and negative electrostatic potentials. The presence of a blue region near the CuII atom and red region near the Cl2 atom in the corresponding surface for (II)[link] in Fig. 7[link](b) is an indication of a short inter­molecular Cu⋯Cl2 inter­action [3.2858 (7) Å], as discussed further below, see Computational chemistry. The influence of ππ stacking inter­actions in each of the crystals of (I)[link] and (II)[link] is evident as the flat regions about the participating aromatic rings on the Hirshfeld surfaces mapped over curvedness illustrated in Fig. 8[link](a)–(d).

[Figure 7]
Figure 7
Views of the Hirshfeld surfaces mapped over the electrostatic potential (the red and blue regions represent negative and positive electrostatic potentials, respectively) for (a) (I)[link] in the range −0.084 to +0.061 atomic units and (b) (II)[link] in the range −0.095 to +0.163 atomic units.
[Figure 8]
Figure 8
Views of Hirshfeld surfaces mapped over curvedness for (a) and (b) (I)[link], and (c) and (d) for (II)[link]. The flat regions about aromatic constituents labelled with Cg(1)–Cg(4) for (I)[link], and Cg(1) and Cg(2) for (II)[link] indicate the involvement of these rings in ππ stacking inter­actions

Given the different coordination geometries in (I)[link] and (II)[link], it was thought of inter­est to calculate the Hirshfeld surfaces about the individual metal centres (Pinto et al., 2019[Pinto, C. B., Dos Santos, L. H. R. & Rodrigues, B. L. (2019). Acta Cryst. C75, 707-716.]). The different coordination geometries, approximately trigonal pyramidal for CoII, Fig. 9[link](a) and (b), and square-planar for CuII in Fig. 9[link](c) and (d), are clearly evident from the illus­trated surfaces although the M—O and M—N bond lengths are similar, at least to a first approximation, in (I)[link] and (II)[link], Table 1[link].

[Figure 9]
Figure 9
Views of the Hirshfeld surfaces calculated for the CoII (I)[link] and CuII (II)[link] centres alone, highlighting the coordination geometries formed by the N2O2 donor sets mapped over (a) the distance de external to the surface in the range 0.922 to 2.221 Å for (I)[link], (b) the shape-index (S) from −1.0 to +1.0 (arbitrary units) for (I)[link], (c) the distance de external to the surface in the range 0.919 to 2.114 Å for (II)[link] and (d) the shape-index (S) from −1.0 to +1.0 (arbitrary units) for (II)[link].

The different coordination geometries about the metal centres are also reflected in the two-dimensional fingerprint plots shown in Fig. 10[link], only taking into account the Hirshfeld surface about the metal atom. The distribution of aligned red points from de + di ∼1.8 Å (lower portion) and de + di ∼2.0 Å (upper portion) for the Co—O and Co—N bonds, respectively, in (I)[link] show different inclinations, Fig. 10[link](a), whereas the superimposed red points in the case of (II)[link], Fig. 10[link](b), arise as a result of the symmetrical coordination geometry. For (I)[link], the presence of short intra­molecular Co⋯H contacts formed with the chloro­benzene-H8 and H22 atoms (Co⋯H8 = 2.64 Å and Co⋯H22 = 2.55 Å) result in dissymmetry in the Hirshfeld surface and are characterized as bright-orange spots on the shape-index-mapped surface in Fig. 9[link](a). The square-planar coordination geometry formed by the N2O2 donor set in (II)[link] results in an approximate cuboid Hirshfeld surface with rounded corners and edges.

[Figure 10]
Figure 10
The two-dimensional fingerprint plots taking into account only the Hirshfeld surface about the metal centre in (a) (I)[link] and (b) (II)[link].

The overall two-dimensional fingerprint plots for (I)[link] and (II)[link] are shown in Fig. 11[link](a), and those delineated into H⋯H, O⋯H/H⋯O, Cl⋯H/H⋯Cl, C⋯H/H⋯C and C⋯C contacts are illustrated in Fig. 11[link](b)–11(f), respectively. The percentage contributions from different inter­atomic contacts to the Hirshfeld surfaces of (I)[link] and (II)[link] are summarized in Table 4[link]. The presence of chloride in both crystals, and their participation in inter­molecular contacts, has decreased the percentage contributions from H⋯H contacts to the respective Hirshfeld surfaces, Table 4[link].

[Figure 11]
Figure 11
(a) A comparison of the full two-dimensional fingerprint plot for each of (I)[link] and (II)[link] and those delineated into (b) H⋯H, (c) O⋯H/H⋯O, (d) Cl⋯H/H⋯Cl, (e) C⋯H/H⋯C and (f) C⋯C contacts.

In the fingerprint plot delineated into H⋯H contacts of Fig. 11[link](b), the short inter­atomic contacts result in a peak at de + di ∼2.3 Å in the crystal of (I)[link] while H⋯H in (II)[link] are at van der Waals separations or longer. The presence of the C—H⋯O contact in (I)[link] is recognized as the pair of spikes at de + di ∼2.2 Å in the fingerprint plot delineated into O⋯H/H⋯O contacts of Fig. 11[link](c) whereas the comparatively small contribution from these contacts in (II)[link], Table 4[link], show the points farther than sum of their van der Waals radii. The pair of forceps-like tips at de + di ∼2.8 Å in the fingerprint plots delineated into Cl⋯H/H⋯Cl contacts in Fig. 11[link](d) for each of (I)[link] and (II)[link] reflect the presence of Cl⋯H contacts in their crystals; for (II)[link], these are beyond the sum of the van der Waals radii. From the fingerprint plot delineated into C⋯H/H⋯C contacts, Fig. 11[link](e), the pair of short tips at de + di ∼2.7 Å indicate the presence of C⋯H and C—H⋯π contacts in (I)[link], by contrast to only van der Waals contacts in (II)[link]. In the fingerprint plot delineated into C⋯C contacts for (I)[link] and (II)[link], Fig. 11[link](f), the influence of ππ stacking inter­actions are characterized as the distribution of green points in the plot around de = di = 1.8 Å.

Referring to Fig. 12[link](a), the distribution of points in the form of a thin line from de + di ∼3.7 Å in the fingerprint plot delineated into Cl⋯Cl contacts for (I)[link] is an indication of influence of these contacts on the packing of (I)[link]; this is confirmed in the next section, Computational study. The fingerprint plot delineated into Cu⋯Cl/Cl⋯Cu contacts of Fig. 12[link](b), with the small, i.e. 1.9%, but important contribution to the Hirshfeld surface of (II)[link] is the result of a Cu⋯Cl inter­action prominent in its mol­ecular packing, as justified from the inter­action energy calculations described in the next section.

[Figure 12]
Figure 12
The fingerprint plot delineated into (a) Cl⋯Cl contacts for (I)[link] and (b) Cu⋯Cl/Cl⋯Cu contacts for (II)[link].

5. Computational chemistry

The pairwise inter­action energies between the mol­ecules in the crystals of each of (I)[link] and (II)[link] were calculated by summing up four energy components, comprising electrostatic (Eele), polarization (Epol), dispersion (Edis) and exchange-repulsion (Erep) as per the literature (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.]). In the present study, the energies were obtained by using the wave function calculated at the HF/3-21G level of theory. The nature and the strength of the energies for the key identified inter­molecular inter­actions are qu­anti­tatively summarized in Tables 5[link] and 6[link] for (I)[link] and (II)[link], respectively.

Table 5
Summary of inter­action energies (kJ mol−1) calculated for (I)

Contact R (Å) Eele Epol Edis Erep Etot
H27⋯Coi + 8.81 −21.7 −6.7 −71.3 41.6 −57.0
C27⋯Coi +            
C27—H27⋯O1i +            
Cg(C15–C20)⋯Cg(C23–C28)i            
Cg(C9–C14) ⋯Cg(C9–C14)ii 9.60 −29.6 −7.6 −71.9 32.5 −73.5
Cg(C1–C6) ⋯Cg(C1–C6)iii 10.19 −23.4 −5.5 −58.3 29.4 −56.0
Cl4⋯H3iv + 10.54 −12.7 −1.2 −26.4 19.8 −21.4
Cl1⋯Cl3iv            
Cl3⋯H7v 10.48 −3.9 −1.3 −14.8 13.4 −7.3
C1⋯H26vi + 9.86 −37.0 −8.0 −84.1 48.4 −79.5
C6⋯H26vi +            
C25–H25⋯Cg(C1–C6)vi +            
Cg(C23–C28)⋯Cg(C23–C28)vi            
Symmetry codes: (i) 1 + x, y, z; (ii) 1 − x, − y, 2 − z; (iii) 1 − x, − y, 1 − z; (iv) 2 − x, − y, 1 − z; (v) x, 1 + y, z; (vi) 2 − x, 1 − y, 1 − z.

Table 6
Summary of inter­action energies (kJ mol−1) calculated for (II)

Contact R (Å) Eele Epol Edis Erep Etot
Cg(C9–C14)⋯Cg(C9–C14)i 12.94 −0.7 −3.0 −44.5 14.8 −30.8
Cu⋯Cl2ii 8.13 −33.0 −5.6 −64.1 44.4 −59.0
Cl1⋯H7iii 9.74 −3.7 −2.5 −25.7 15.4 −16.0
C5⋯C7iv + 8.51 −14.4 −4.7 −68.5 36.8 −49.6
Cg(C1–C6)⋯Cg(C1–C6)iv            
Symmetry codes: (i) − x, 1 − y, − z; (ii) 1 + x, y, z; (iii) 1 − x, 1 − y, −z; (iv) 1 − x, − y, 1 − z.

For (I)[link], among the inter­molecular energies listed in Table 5[link], the atoms of (C23–C28) ring involved in the short inter­atomic C⋯H/H⋯C contacts, inter­molecular C—H⋯π and ππ stacking inter­actions between the same pair of symmetry-related mol­ecules have maximum inter­action energies. The dispersive component makes a major contribution to all of the inter­molecular inter­actions in the crystal of (I)[link]. The low inter­action energies for Cl⋯H and Cl⋯Cl contacts are consistent with the small contributions from these contacts in the crystal. The presence of a Cu⋯Cl2 contact in the crystal of (II)[link] is an important feature of the packing. This inter­action shows maximum inter­action energy (Table 6[link]) with significant contributions from the electrostatic component compared to ππ stacking and other inter­molecular inter­actions influential in the mol­ecular packing.

The magnitudes of inter­molecular energies are represented graphically in the energy framework diagrams of Fig. 13[link](a)–(f). Here, the supra­molecular architecture of each crystal is visualized through cylinders joining the centroids of mol­ecular pairs using a red, green and blue colour scheme, representing the Eele, Edisp and Etot components, respectively; the stronger the inter­action, the thicker the cylinder.

[Figure 13]
Figure 13
The energy frameworks calculated for (I)[link] showing the (a) electrostatic potential force, (b) dispersion force and (c) total energy; the equivalent diagrams for (II)[link] are shown in (d)–(f). The energy frameworks were adjusted to the same to same scale factor of 30 with a cut-off value of 3 kJ mol−1 within 2 × 2 × 2 unit cells.

6. Database survey

Schiff bases related to those reported in (I)[link] and (II)[link], i.e. having two imine functionalities and a single phenol/phenoxide atom/ion on one ring only are quite rare. Thus, the only structure of an analogue available for comparison is a N,O-chelated di­methyl­aluminium compound with the ring bearing the phenoxide-oxygen also carrying t-butyl groups at the 3,5 positions and the second benzene ring bearing a chlorine atom in the 4-position (UPEKEH; Hsu et al., 2017[Hsu, C.-Y., Tseng, H.-C., Vandavasi, J. K., Lu, W.-Y., Wang, L.-F., Chiang, M. Y., Lai, Y.-C., Chen, H.-Y. & Chen, H. (2017). RSC Adv. 7, 18851-18860.]). By contrast, there are numerous examples of coordination complexes derived from Schiff base mol­ecules with two 2-phenol substituents in each ring, LH2. In these instances, the dinegative Schiff base anion N,O-chelates two metal centres such as in binuclear Co2(L1)3 (JUKZOG; Liu et al., 2015[Liu, E., Zhang, Y. Z., Tan, J., Yang, C., Li, L., Golen, J. A., Rheingold, A. L. & Zhang, G. (2015). Polyhedron, 102, 41-47.]), with a fac-N3O3 donor set within an octa­hedral geometry, and Cu2(L2)3(PPh3)2 (VOWBAM; Prakash et al., 2015[Prakash, G., Nirmala, M., Ramachandran, R., Viswanathamurthi, P., Malecki, J. G. & Sanmartin, J. (2015). Polyhedron, 89, 62-69.]) with tetra­hedral NOP2 donor sets; for the L1 dianion, there are 3-eth­oxy substituents in each ring and for L2, the are 4-chloro substituents.

7. Synthesis and crystallization

The title complexes (I)[link] and (II)[link] were synthesized according to the literature procedure (Manawar, Gondaliya, Mamtora et al., 2019[Manawar, R. B., Gondaliya, M. B., Mamtora, M. J. & Shah, M. K. (2019). Sci. News 126, 222-247.]). Briefly, the complexes were obtained by mixing the Schiff base, in ethanol, with an aqueous solution of the corresponding metal chloride in 1:1 and 1:2 molar ratios, respectively, in the presence of piperidine as basic catalyst for proton abstraction from the ligand mol­ecules. The crystals in the form of red (I)[link] and dark-brown (II)[link] blocks were grown by slow evaporation from their respective chloro­form solutions.

8. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 7[link]. The carbon-bound H atoms were placed in calculated positions (C—H = 0.93 Å) and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.2Ueq(C).

Table 7
Experimental details

  (I) (II)
Crystal data
Chemical formula [Co(C14H9Cl2N2O)2] [Cu(C14H9Cl2N2O)2]
Mr 643.19 647.80
Crystal system, space group Triclinic, P[\overline{1}] Triclinic, P[\overline{1}]
Temperature (K) 296 296
a, b, c (Å) 8.8137 (10), 10.4801 (12), 15.0785 (17) 8.1300 (7), 8.5072 (11), 9.7386 (13)
α, β, γ (°) 85.684 (7), 77.984 (7), 84.965 (7) 83.240 (4), 87.646 (3), 81.533 (4)
V3) 1354.7 (3) 661.39 (14)
Z 2 1
Radiation type Mo Kα Mo Kα
μ (mm−1) 1.06 1.27
Crystal size (mm) 0.35 × 0.30 × 0.30 0.35 × 0.35 × 0.30
 
Data collection
Diffractometer Bruker Kappa APEXII CCD Bruker Kappa APEXII CCD
Absorption correction Multi-scan (SADABS; Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Multi-scan (SADABS; Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.631, 0.746 0.637, 0.714
No. of measured, independent and observed [I > 2σ(I)] reflections 45690, 6959, 4590 5554, 3090, 2708
Rint 0.102 0.021
(sin θ/λ)max−1) 0.678 0.667
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.112, 1.04 0.033, 0.093, 1.05
No. of reflections 6959 3090
No. of parameters 352 178
H-atom treatment H-atom parameters constrained H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.45, −0.50 0.44, −0.46
Computer programs: APEX2 and SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]),SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]), SHELXL2017/1 (Sheldrick, 2015[Sheldrick, G. M. (2015). 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

For both structures, data collection: APEX2 (Bruker, 2004); cell refinement: APEX2/SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL2017/1 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012), DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Bis(2-{[(2,6-dichlorobenzylidene)hydrazinylidene]methyl}phenolato)cobalt(II) (I) top
Crystal data top
[Co(C14H9Cl2N2O)2]Z = 2
Mr = 643.19F(000) = 650
Triclinic, P1Dx = 1.577 Mg m3
a = 8.8137 (10) ÅMo Kα radiation, λ = 0.71073 Å
b = 10.4801 (12) ÅCell parameters from 5585 reflections
c = 15.0785 (17) Åθ = 2.3–22.4°
α = 85.684 (7)°µ = 1.06 mm1
β = 77.984 (7)°T = 296 K
γ = 84.965 (7)°Block, red
V = 1354.7 (3) Å30.35 × 0.30 × 0.30 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
4590 reflections with I > 2σ(I)
Radiation source: X-ray tubeRint = 0.102
ω and φ scanθmax = 28.8°, θmin = 1.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 1111
Tmin = 0.631, Tmax = 0.746k = 1414
45690 measured reflectionsl = 2020
6959 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.112H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.031P)2 + 0.0591P]
where P = (Fo2 + 2Fc2)/3
6959 reflections(Δ/σ)max = 0.001
352 parametersΔρmax = 0.45 e Å3
0 restraintsΔρmin = 0.50 e Å3
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
Co0.44734 (4)0.27310 (3)0.68541 (2)0.03428 (11)
Cl10.88398 (11)0.08192 (9)0.85762 (6)0.0821 (3)
Cl20.45007 (10)0.29954 (8)0.98752 (6)0.0675 (2)
Cl30.79790 (9)0.73174 (7)0.69395 (6)0.0643 (2)
Cl40.96728 (8)0.23680 (7)0.60664 (6)0.0566 (2)
O10.48493 (19)0.28424 (16)0.55684 (12)0.0386 (4)
O20.25211 (19)0.24964 (17)0.76315 (12)0.0441 (4)
N10.6051 (2)0.12543 (18)0.69189 (13)0.0310 (4)
N20.6554 (2)0.0714 (2)0.77036 (14)0.0411 (5)
N30.4754 (2)0.43864 (19)0.73568 (14)0.0352 (5)
N40.6127 (2)0.5040 (2)0.71934 (17)0.0470 (6)
C10.5601 (3)0.1984 (2)0.50173 (16)0.0320 (5)
C20.6504 (3)0.0906 (2)0.53011 (16)0.0328 (5)
C30.7307 (3)0.0055 (3)0.46435 (18)0.0424 (6)
H30.7889700.0658350.4832330.051*
C40.7258 (3)0.0241 (3)0.37463 (19)0.0496 (7)
H40.7809240.0321280.3324570.060*
C50.6353 (3)0.1305 (3)0.34809 (19)0.0488 (7)
H50.6296420.1442820.2871660.059*
C60.5546 (3)0.2148 (3)0.40882 (17)0.0403 (6)
H60.4950890.2842770.3885050.048*
C70.6684 (3)0.0616 (2)0.62082 (17)0.0355 (6)
H70.7324560.0111480.6307920.043*
C80.6244 (3)0.1407 (3)0.83673 (17)0.0394 (6)
H80.5747990.2215940.8288830.047*
C90.6609 (3)0.1035 (2)0.92574 (17)0.0377 (6)
C100.7686 (3)0.0031 (3)0.94344 (19)0.0467 (7)
C110.7896 (4)0.0315 (3)1.0308 (2)0.0573 (8)
H110.8607990.0990671.0410030.069*
C120.7048 (4)0.0344 (4)1.1022 (2)0.0646 (9)
H120.7178690.0100931.1609090.078*
C130.6007 (4)0.1359 (3)1.0883 (2)0.0588 (8)
H130.5445910.1808951.1369120.071*
C140.5809 (3)0.1697 (3)1.00133 (19)0.0448 (7)
C150.1585 (3)0.3409 (3)0.80467 (17)0.0397 (6)
C160.2042 (3)0.4638 (3)0.81575 (18)0.0410 (6)
C170.0932 (3)0.5554 (3)0.8613 (2)0.0575 (8)
H170.1239820.6356190.8694470.069*
C180.0578 (4)0.5289 (4)0.8936 (2)0.0671 (10)
H180.1302120.5911630.9212420.081*
C190.1010 (3)0.4085 (4)0.8846 (2)0.0649 (9)
H190.2032860.3894790.9077620.078*
C200.0023 (3)0.3155 (3)0.84240 (19)0.0523 (8)
H200.0306650.2345600.8385230.063*
C210.3586 (3)0.5031 (3)0.78469 (19)0.0440 (7)
H210.3777080.5829550.8012100.053*
C220.7287 (3)0.4444 (2)0.67455 (18)0.0374 (6)
H220.7128040.3641150.6571690.045*
C230.8864 (3)0.4856 (2)0.64614 (16)0.0333 (5)
C240.9300 (3)0.6101 (2)0.64938 (19)0.0414 (6)
C251.0819 (3)0.6408 (3)0.6154 (2)0.0511 (7)
H251.1089210.7240060.6181880.061*
C261.1928 (3)0.5492 (3)0.5775 (2)0.0525 (8)
H261.2939270.5711990.5539320.063*
C271.1554 (3)0.4260 (3)0.57441 (18)0.0453 (7)
H271.2303920.3637950.5490570.054*
C281.0048 (3)0.3955 (3)0.60946 (18)0.0384 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co0.03317 (18)0.0346 (2)0.0336 (2)0.00280 (14)0.00453 (14)0.00479 (15)
Cl10.1017 (7)0.0828 (6)0.0679 (6)0.0502 (5)0.0448 (5)0.0328 (5)
Cl20.0717 (5)0.0700 (6)0.0533 (5)0.0181 (4)0.0018 (4)0.0142 (4)
Cl30.0601 (5)0.0356 (4)0.1007 (7)0.0009 (3)0.0221 (4)0.0150 (4)
Cl40.0460 (4)0.0380 (4)0.0810 (6)0.0041 (3)0.0014 (4)0.0129 (4)
O10.0414 (9)0.0376 (10)0.0348 (10)0.0096 (8)0.0074 (8)0.0044 (8)
O20.0387 (9)0.0430 (11)0.0459 (12)0.0004 (8)0.0022 (8)0.0058 (9)
N10.0356 (10)0.0300 (11)0.0274 (11)0.0004 (8)0.0075 (9)0.0003 (9)
N20.0546 (13)0.0363 (13)0.0329 (13)0.0050 (10)0.0137 (10)0.0005 (10)
N30.0302 (10)0.0345 (12)0.0393 (13)0.0028 (9)0.0046 (9)0.0045 (10)
N40.0381 (12)0.0387 (13)0.0618 (16)0.0019 (10)0.0005 (11)0.0162 (12)
C10.0331 (12)0.0312 (13)0.0321 (14)0.0049 (10)0.0069 (10)0.0014 (11)
C20.0374 (13)0.0315 (13)0.0303 (13)0.0020 (10)0.0076 (10)0.0059 (11)
C30.0452 (15)0.0403 (16)0.0414 (16)0.0036 (12)0.0086 (12)0.0087 (13)
C40.0596 (17)0.0513 (18)0.0366 (16)0.0003 (14)0.0036 (13)0.0166 (14)
C50.0617 (18)0.0576 (19)0.0302 (15)0.0106 (15)0.0126 (13)0.0062 (14)
C60.0453 (14)0.0424 (16)0.0347 (15)0.0019 (12)0.0131 (12)0.0010 (12)
C70.0407 (13)0.0293 (13)0.0357 (15)0.0045 (10)0.0085 (11)0.0031 (11)
C80.0463 (14)0.0368 (15)0.0349 (15)0.0065 (12)0.0112 (12)0.0034 (12)
C90.0461 (14)0.0375 (15)0.0306 (14)0.0059 (12)0.0096 (11)0.0010 (12)
C100.0574 (17)0.0446 (17)0.0423 (17)0.0006 (13)0.0195 (14)0.0087 (13)
C110.076 (2)0.0532 (19)0.0510 (19)0.0012 (16)0.0361 (17)0.0022 (16)
C120.083 (2)0.079 (2)0.0371 (18)0.015 (2)0.0227 (17)0.0032 (17)
C130.074 (2)0.070 (2)0.0328 (17)0.0076 (18)0.0091 (15)0.0092 (16)
C140.0535 (16)0.0464 (17)0.0349 (15)0.0098 (13)0.0069 (12)0.0034 (13)
C150.0344 (13)0.0524 (17)0.0295 (14)0.0004 (12)0.0033 (11)0.0037 (12)
C160.0372 (13)0.0466 (16)0.0343 (15)0.0073 (12)0.0004 (11)0.0030 (12)
C170.0498 (17)0.0564 (19)0.056 (2)0.0133 (14)0.0064 (14)0.0076 (16)
C180.0467 (17)0.076 (3)0.065 (2)0.0186 (17)0.0105 (15)0.0072 (19)
C190.0350 (15)0.097 (3)0.055 (2)0.0029 (17)0.0038 (14)0.0023 (19)
C200.0389 (15)0.064 (2)0.0497 (19)0.0041 (14)0.0014 (13)0.0016 (15)
C210.0416 (14)0.0365 (15)0.0509 (18)0.0043 (12)0.0035 (12)0.0081 (13)
C220.0348 (13)0.0298 (14)0.0482 (16)0.0003 (10)0.0097 (11)0.0057 (12)
C230.0348 (12)0.0344 (14)0.0317 (14)0.0014 (10)0.0110 (10)0.0014 (11)
C240.0452 (15)0.0350 (15)0.0491 (17)0.0046 (11)0.0215 (13)0.0001 (12)
C250.0534 (17)0.0454 (17)0.061 (2)0.0170 (14)0.0232 (15)0.0048 (15)
C260.0381 (15)0.068 (2)0.0531 (19)0.0158 (14)0.0116 (13)0.0036 (16)
C270.0345 (13)0.0602 (19)0.0405 (16)0.0005 (13)0.0077 (12)0.0025 (14)
C280.0365 (13)0.0405 (15)0.0387 (15)0.0001 (11)0.0114 (11)0.0014 (12)
Geometric parameters (Å, º) top
Co—O21.8937 (17)C9—C141.406 (4)
Co—O11.8940 (17)C10—C111.385 (4)
Co—N11.9988 (19)C11—C121.371 (4)
Co—N31.999 (2)C11—H110.9300
Cl1—C101.723 (3)C12—C131.376 (4)
Cl2—C141.733 (3)C12—H120.9300
Cl3—C241.725 (3)C13—C141.375 (4)
Cl4—C281.729 (3)C13—H130.9300
O1—C11.310 (3)C15—C201.416 (3)
O2—C151.313 (3)C15—C161.414 (4)
N1—C71.304 (3)C16—C171.416 (4)
N1—N21.411 (3)C16—C211.431 (3)
N2—C81.251 (3)C17—C181.363 (4)
N3—C211.303 (3)C17—H170.9300
N3—N41.410 (3)C18—C191.374 (5)
N4—C221.247 (3)C18—H180.9300
C1—C61.409 (3)C19—C201.371 (4)
C1—C21.416 (3)C19—H190.9300
C2—C31.417 (3)C20—H200.9300
C2—C71.417 (3)C21—H210.9300
C3—C41.361 (4)C22—C231.461 (3)
C3—H30.9300C22—H220.9300
C4—C51.396 (4)C23—C281.397 (3)
C4—H40.9300C23—C241.399 (3)
C5—C61.366 (4)C24—C251.388 (4)
C5—H50.9300C25—C261.374 (4)
C6—H60.9300C25—H250.9300
C7—H70.9300C26—C271.367 (4)
C8—C91.461 (3)C26—H260.9300
C8—H80.9300C27—C281.379 (3)
C9—C101.402 (4)C27—H270.9300
O2—Co—O1125.33 (8)C11—C12—H12119.5
O2—Co—N1113.82 (8)C13—C12—H12119.5
O1—Co—N194.06 (7)C14—C13—C12119.0 (3)
O2—Co—N394.60 (8)C14—C13—H13120.5
O1—Co—N3112.12 (8)C12—C13—H13120.5
N1—Co—N3119.03 (8)C13—C14—C9122.7 (3)
C1—O1—Co127.34 (15)C13—C14—Cl2117.0 (2)
C15—O2—Co125.37 (16)C9—C14—Cl2120.3 (2)
C7—N1—N2111.4 (2)O2—C15—C20118.7 (3)
C7—N1—Co121.70 (16)O2—C15—C16124.1 (2)
N2—N1—Co126.78 (15)C20—C15—C16117.2 (2)
C8—N2—N1114.8 (2)C15—C16—C17119.4 (2)
C21—N3—N4112.1 (2)C15—C16—C21124.2 (2)
C21—N3—Co121.09 (17)C17—C16—C21116.4 (3)
N4—N3—Co126.71 (15)C18—C17—C16121.6 (3)
C22—N4—N3114.3 (2)C18—C17—H17119.2
O1—C1—C6118.8 (2)C16—C17—H17119.2
O1—C1—C2123.5 (2)C17—C18—C19118.9 (3)
C6—C1—C2117.7 (2)C17—C18—H18120.6
C3—C2—C7116.8 (2)C19—C18—H18120.6
C3—C2—C1118.9 (2)C18—C19—C20121.9 (3)
C7—C2—C1124.4 (2)C18—C19—H19119.0
C4—C3—C2122.6 (3)C20—C19—H19119.0
C4—C3—H3118.7C19—C20—C15120.9 (3)
C2—C3—H3118.7C19—C20—H20119.5
C3—C4—C5117.7 (3)C15—C20—H20119.5
C3—C4—H4121.1N3—C21—C16126.8 (3)
C5—C4—H4121.1N3—C21—H21116.6
C6—C5—C4122.1 (3)C16—C21—H21116.6
C6—C5—H5119.0N4—C22—C23127.7 (2)
C4—C5—H5119.0N4—C22—H22116.1
C5—C6—C1121.1 (3)C23—C22—H22116.1
C5—C6—H6119.5C28—C23—C24116.2 (2)
C1—C6—H6119.5C28—C23—C22118.2 (2)
N1—C7—C2127.3 (2)C24—C23—C22125.6 (2)
N1—C7—H7116.4C25—C24—C23120.9 (3)
C2—C7—H7116.4C25—C24—Cl3117.3 (2)
N2—C8—C9124.5 (2)C23—C24—Cl3121.8 (2)
N2—C8—H8117.7C26—C25—C24120.5 (3)
C9—C8—H8117.7C26—C25—H25119.7
C10—C9—C14116.0 (2)C24—C25—H25119.7
C10—C9—C8125.2 (2)C27—C26—C25120.4 (3)
C14—C9—C8118.8 (2)C27—C26—H26119.8
C11—C10—C9121.7 (3)C25—C26—H26119.8
C11—C10—Cl1116.5 (2)C26—C27—C28118.9 (3)
C9—C10—Cl1121.8 (2)C26—C27—H27120.5
C12—C11—C10119.7 (3)C28—C27—H27120.5
C12—C11—H11120.2C27—C28—C23123.1 (2)
C10—C11—H11120.2C27—C28—Cl4116.4 (2)
C11—C12—C13121.0 (3)C23—C28—Cl4120.48 (19)
O2—Co—O1—C1108.33 (19)C12—C13—C14—Cl2179.2 (2)
N1—Co—O1—C114.8 (2)C10—C9—C14—C132.7 (4)
N3—Co—O1—C1138.45 (19)C8—C9—C14—C13175.8 (3)
O1—Co—O2—C1599.8 (2)C10—C9—C14—Cl2177.6 (2)
N1—Co—O2—C15146.13 (19)C8—C9—C14—Cl23.9 (3)
N3—Co—O2—C1521.5 (2)Co—O2—C15—C20164.92 (18)
C7—N1—N2—C8166.6 (2)Co—O2—C15—C1616.2 (4)
Co—N1—N2—C817.3 (3)O2—C15—C16—C17179.6 (3)
C21—N3—N4—C22178.3 (2)C20—C15—C16—C171.4 (4)
Co—N3—N4—C226.0 (3)O2—C15—C16—C211.3 (4)
Co—O1—C1—C6169.84 (16)C20—C15—C16—C21177.6 (2)
Co—O1—C1—C211.6 (3)C15—C16—C17—C181.1 (4)
O1—C1—C2—C3178.2 (2)C21—C16—C17—C18179.7 (3)
C6—C1—C2—C30.3 (3)C16—C17—C18—C192.6 (5)
O1—C1—C2—C71.0 (4)C17—C18—C19—C201.5 (5)
C6—C1—C2—C7179.5 (2)C18—C19—C20—C151.2 (5)
C7—C2—C3—C4178.5 (2)O2—C15—C20—C19178.5 (3)
C1—C2—C3—C40.7 (4)C16—C15—C20—C192.5 (4)
C2—C3—C4—C51.2 (4)N4—N3—C21—C16178.3 (2)
C3—C4—C5—C60.6 (4)Co—N3—C21—C165.7 (4)
C4—C5—C6—C10.4 (4)C15—C16—C21—N36.4 (4)
O1—C1—C6—C5177.8 (2)C17—C16—C21—N3174.5 (3)
C2—C1—C6—C50.8 (4)N3—N4—C22—C23179.7 (2)
N2—N1—C7—C2177.2 (2)N4—C22—C23—C28169.5 (3)
Co—N1—C7—C26.5 (3)N4—C22—C23—C2412.9 (4)
C3—C2—C7—N1179.5 (2)C28—C23—C24—C251.7 (4)
C1—C2—C7—N11.3 (4)C22—C23—C24—C25176.0 (2)
N1—N2—C8—C9178.1 (2)C28—C23—C24—Cl3179.22 (19)
N2—C8—C9—C1017.7 (4)C22—C23—C24—Cl33.1 (4)
N2—C8—C9—C14160.7 (3)C23—C24—C25—C260.1 (4)
C14—C9—C10—C112.5 (4)Cl3—C24—C25—C26179.0 (2)
C8—C9—C10—C11175.9 (3)C24—C25—C26—C271.2 (4)
C14—C9—C10—Cl1176.4 (2)C25—C26—C27—C280.2 (4)
C8—C9—C10—Cl15.2 (4)C26—C27—C28—C231.8 (4)
C9—C10—C11—C120.8 (5)C26—C27—C28—Cl4177.9 (2)
Cl1—C10—C11—C12178.2 (3)C24—C23—C28—C272.7 (4)
C10—C11—C12—C131.0 (5)C22—C23—C28—C27175.1 (2)
C11—C12—C13—C140.9 (5)C24—C23—C28—Cl4176.99 (19)
C12—C13—C14—C91.1 (4)C22—C23—C28—Cl45.2 (3)
Hydrogen-bond geometry (Å, º) top
Cg3 is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
C27—H27···O1i0.932.353.114 (3)140
C25—H25···Cg3ii0.932.863.647 (3)143
Symmetry codes: (i) x+1, y, z; (ii) x+2, y+1, z+1.
Bis(2-{[(2,6-dichlorobenzylidene)hydrazinylidene]methyl}phenolato)copper(II) (II) top
Crystal data top
[Cu(C14H9Cl2N2O)2]Z = 1
Mr = 647.80F(000) = 327
Triclinic, P1Dx = 1.626 Mg m3
a = 8.1300 (7) ÅMo Kα radiation, λ = 0.71073 Å
b = 8.5072 (11) ÅCell parameters from 3126 reflections
c = 9.7386 (13) Åθ = 4.9–56.5°
α = 83.240 (4)°µ = 1.26 mm1
β = 87.646 (3)°T = 296 K
γ = 81.533 (4)°Block, dark-brown
V = 661.39 (14) Å30.35 × 0.35 × 0.30 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2708 reflections with I > 2σ(I)
ω and φ scanRint = 0.021
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
θmax = 28.3°, θmin = 3.3°
Tmin = 0.637, Tmax = 0.714h = 510
5554 measured reflectionsk = 1111
3090 independent reflectionsl = 1212
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.033Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.093H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0461P)2 + 0.2934P]
where P = (Fo2 + 2Fc2)/3
3090 reflections(Δ/σ)max < 0.001
178 parametersΔρmax = 0.44 e Å3
0 restraintsΔρmin = 0.46 e Å3
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
Cu0.5000000.5000000.5000000.02898 (11)
Cl10.31832 (11)0.73971 (12)0.01621 (8)0.0830 (3)
Cl20.14142 (7)0.45455 (7)0.33048 (7)0.05364 (17)
O10.5954 (2)0.30738 (17)0.59863 (16)0.0435 (4)
N10.4436 (2)0.37945 (19)0.34549 (16)0.0293 (3)
N20.3392 (2)0.4457 (2)0.23415 (17)0.0352 (4)
C10.6593 (3)0.1736 (2)0.5513 (2)0.0338 (4)
C20.6301 (3)0.1364 (2)0.4182 (2)0.0325 (4)
C30.7051 (3)0.0117 (3)0.3762 (3)0.0439 (5)
H30.6844700.0368210.2886720.053*
C40.8071 (3)0.1183 (3)0.4617 (3)0.0519 (6)
H40.8576190.2142330.4320710.062*
C50.8345 (3)0.0824 (3)0.5923 (3)0.0519 (6)
H50.9032700.1555020.6508830.062*
C60.7625 (3)0.0588 (3)0.6378 (3)0.0459 (5)
H60.7820380.0792040.7269630.055*
C70.5198 (3)0.2392 (2)0.3251 (2)0.0321 (4)
H70.5009960.2018270.2420300.038*
C80.2031 (2)0.5217 (2)0.2710 (2)0.0327 (4)
H80.1797950.5260760.3648700.039*
C90.0790 (3)0.6043 (2)0.1705 (2)0.0338 (4)
C100.1164 (3)0.7083 (3)0.0554 (2)0.0456 (5)
C110.0074 (4)0.7920 (3)0.0292 (3)0.0597 (7)
H110.0199980.8612100.1050660.072*
C120.1692 (4)0.7730 (3)0.0015 (3)0.0676 (9)
H120.2515920.8306750.0582690.081*
C130.2130 (3)0.6699 (3)0.1091 (3)0.0589 (7)
H130.3233550.6554850.1269540.071*
C140.0872 (3)0.5881 (2)0.1931 (2)0.0392 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu0.02975 (19)0.02729 (17)0.02922 (18)0.00160 (12)0.00773 (12)0.00101 (12)
Cl10.0648 (5)0.1185 (7)0.0567 (4)0.0217 (5)0.0044 (3)0.0361 (4)
Cl20.0335 (3)0.0511 (3)0.0743 (4)0.0079 (2)0.0011 (3)0.0025 (3)
O10.0645 (11)0.0280 (7)0.0364 (8)0.0034 (7)0.0205 (7)0.0033 (6)
N10.0274 (8)0.0338 (8)0.0264 (7)0.0031 (6)0.0058 (6)0.0014 (6)
N20.0360 (9)0.0415 (9)0.0273 (8)0.0016 (7)0.0089 (7)0.0033 (7)
C10.0346 (11)0.0265 (9)0.0404 (10)0.0063 (8)0.0087 (8)0.0015 (7)
C20.0301 (10)0.0297 (9)0.0377 (10)0.0056 (7)0.0007 (8)0.0025 (7)
C30.0474 (14)0.0369 (11)0.0465 (12)0.0020 (9)0.0044 (10)0.0079 (9)
C40.0484 (14)0.0331 (11)0.0702 (17)0.0059 (10)0.0038 (12)0.0057 (11)
C50.0471 (14)0.0335 (11)0.0700 (17)0.0039 (10)0.0135 (12)0.0067 (11)
C60.0529 (14)0.0336 (10)0.0498 (13)0.0026 (9)0.0207 (11)0.0037 (9)
C70.0328 (10)0.0357 (9)0.0287 (9)0.0066 (8)0.0001 (7)0.0061 (7)
C80.0304 (10)0.0414 (10)0.0268 (9)0.0068 (8)0.0060 (7)0.0016 (7)
C90.0350 (11)0.0352 (10)0.0317 (10)0.0016 (8)0.0095 (8)0.0068 (8)
C100.0534 (15)0.0507 (13)0.0318 (10)0.0051 (11)0.0099 (9)0.0014 (9)
C110.084 (2)0.0506 (14)0.0422 (13)0.0036 (13)0.0263 (13)0.0042 (11)
C120.077 (2)0.0517 (15)0.0713 (18)0.0100 (14)0.0474 (16)0.0024 (13)
C130.0419 (15)0.0499 (14)0.085 (2)0.0029 (11)0.0289 (13)0.0106 (13)
C140.0370 (12)0.0330 (10)0.0482 (12)0.0006 (8)0.0126 (9)0.0088 (9)
Geometric parameters (Å, º) top
Cu—O11.8776 (14)C4—H40.9300
Cu—O1i1.8776 (14)C5—C61.371 (3)
Cu—N12.0211 (16)C5—H50.9300
Cu—N1i2.0211 (16)C6—H60.9300
Cl1—C101.722 (3)C7—H70.9300
Cl2—C141.737 (2)C8—C91.476 (3)
O1—C11.306 (2)C8—H80.9300
N1—C71.294 (2)C9—C141.384 (3)
N1—N21.416 (2)C9—C101.396 (3)
N2—C81.258 (3)C10—C111.385 (3)
C1—C61.411 (3)C11—C121.361 (5)
C1—C21.407 (3)C11—H110.9300
C2—C31.415 (3)C12—C131.376 (5)
C2—C71.428 (3)C12—H120.9300
C3—C41.365 (3)C13—C141.387 (3)
C3—H30.9300C13—H130.9300
C4—C51.377 (4)
O1—Cu—O1i180.00 (10)C5—C6—H6119.5
O1—Cu—N190.28 (6)C1—C6—H6119.5
O1i—Cu—N189.72 (6)N1—C7—C2126.18 (18)
O1—Cu—N1i89.72 (6)N1—C7—H7116.9
O1i—Cu—N1i90.28 (6)C2—C7—H7116.9
N1—Cu—N1i180.0N2—C8—C9122.34 (18)
C1—O1—Cu128.77 (13)N2—C8—H8118.8
C7—N1—N2111.28 (16)C9—C8—H8118.8
C7—N1—Cu123.02 (13)C14—C9—C10116.3 (2)
N2—N1—Cu124.88 (12)C14—C9—C8119.63 (19)
C8—N2—N1113.85 (16)C10—C9—C8124.0 (2)
O1—C1—C6118.78 (19)C11—C10—C9121.3 (3)
O1—C1—C2123.59 (18)C11—C10—Cl1117.8 (2)
C6—C1—C2117.63 (19)C9—C10—Cl1120.87 (18)
C1—C2—C3119.48 (19)C12—C11—C10120.1 (3)
C1—C2—C7122.47 (18)C12—C11—H11120.0
C3—C2—C7117.97 (19)C10—C11—H11120.0
C4—C3—C2121.2 (2)C11—C12—C13121.1 (2)
C4—C3—H3119.4C11—C12—H12119.4
C2—C3—H3119.4C13—C12—H12119.4
C3—C4—C5119.3 (2)C14—C13—C12117.9 (3)
C3—C4—H4120.3C14—C13—H13121.1
C5—C4—H4120.3C12—C13—H13121.1
C6—C5—C4121.4 (2)C13—C14—C9123.3 (2)
C6—C5—H5119.3C13—C14—Cl2118.0 (2)
C4—C5—H5119.3C9—C14—Cl2118.66 (16)
C5—C6—C1121.0 (2)
N1—Cu—O1—C125.25 (19)C1—C2—C7—N14.8 (3)
N1i—Cu—O1—C1154.75 (19)C3—C2—C7—N1178.5 (2)
C7—N1—N2—C8141.33 (19)N1—N2—C8—C9178.03 (18)
Cu—N1—N2—C848.8 (2)N2—C8—C9—C14134.7 (2)
Cu—O1—C1—C6163.39 (17)N2—C8—C9—C1049.5 (3)
Cu—O1—C1—C217.0 (3)C14—C9—C10—C111.1 (3)
O1—C1—C2—C3179.9 (2)C8—C9—C10—C11174.8 (2)
C6—C1—C2—C30.5 (3)C14—C9—C10—Cl1179.69 (17)
O1—C1—C2—C73.5 (3)C8—C9—C10—Cl13.8 (3)
C6—C1—C2—C7176.1 (2)C9—C10—C11—C120.4 (4)
C1—C2—C3—C40.9 (3)Cl1—C10—C11—C12179.1 (2)
C7—C2—C3—C4177.7 (2)C10—C11—C12—C130.8 (4)
C2—C3—C4—C51.4 (4)C11—C12—C13—C141.2 (4)
C3—C4—C5—C60.6 (4)C12—C13—C14—C90.5 (4)
C4—C5—C6—C10.9 (4)C12—C13—C14—Cl2178.6 (2)
O1—C1—C6—C5179.0 (2)C10—C9—C14—C130.6 (3)
C2—C1—C6—C51.4 (4)C8—C9—C14—C13175.5 (2)
N2—N1—C7—C2177.83 (19)C10—C9—C14—Cl2177.47 (16)
Cu—N1—C7—C212.1 (3)C8—C9—C14—Cl26.4 (3)
Symmetry code: (i) x+1, y+1, z+1.
Selected geometric parameters (Å, °) for (I) and (II)a top
Parameter(I): M = CoII(II): M = CuII
M—O11.8940 (17)1.8776 (14)
M—O21.8937 (17)1.8776 (14)a
M—N11.9988 (19)2.0211 (16)
M—N31.999 (2)2.0211 (16)a
N1—N21.411 (3)1.416 (2)
N3—N41.410 (3)1.416 (2)a
C7—N11.304 (3)1.294 (2)
C8—N21.251 (3)1.258 (3)
C21—N31.303 (3)1.294 (2)a
C22—N41.247 (3)1.258 (3)a
O1—Co—O2125.33 (8)180a
O1—Co—N194.06 (7)90.28 (6)
O1—Co—N3112.12 (8)89.72 (6)
O2—Co—N1113.82 (8)89.72 (6)a
O2—Co—N394.60 (8)90.28 (6)a
N1—Co—N3119.03 (8)180a
Notes: (a) The CuII atom in (II) lies on a centre of inversion so O2 is equivalent to O1, N3 to N1, etc. and are related by the symmetry operation 1 - x, 1 - y, 1 - z.
Summary of short interatomic contacts (Å) in (I) and (II)a top
ContactDistanceSymmetry operation
(I)
Cl1···Cl33.4993 (13)x, -1 + y, z
Cl3···H72.70x, 1 + y, z
Cl4···H32.742 - x, - y, 1 - z
C1···H262.712 - x, 1 - y, 1 - z
C6···H262.762 - x, 1 - y, 1 - z
Co···C273.558 (3)-1 + x, y, z
Co···H273.08-1 + x, y, z
H5···H122.23x, y, -1 + z
H5···H132.30x, y, -1 + z
(II)
Cl1···H72.811 - x, 1 - y, -z
C5···C73.378 (3)1 - x, -y, 1 - z
Cu···Cl23.2858 (7)1 + x, y, 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.
Percentage contributions of interatomic contacts to the Hirshfeld surface for (I) and (II) top
ContactPercentage contribution
(I)(II)
H···H26.230.5
O···H/H···O7.94.2
C···H/H···C16.714.5
Cl···H/H···Cl25.824.9
C···C12.09.8
N···H/H··· N5.56.2
Cl···Cl2.20.4
C···O/O···C0.50.3
C···N/N···C0.51.3
Cl···O/O···Cl0.20.4
C···Cl/Cl···C1.93.9
Cl···N/N···Cl0.21.6
M···H/H···M0.40.1
M···Cl/Cl···M0.01.9
Summary of interaction energies (kJ mol-1) calculated for (I) top
ContactR (Å)EeleEpolEdisErepEtot
H27···Coi +8.81-21.7-6.7-71.341.6-57.0
C27···Coi +
C27—H27···O1i +
Cg(C15–C20)···Cg(C23–C28)i
Cg(C9–C14) ···Cg(C9–C14)ii9.60-29.6-7.6-71.932.5-73.5
Cg(C1–C6) ···Cg(C1–C6)iii10.19-23.4-5.5-58.329.4-56.0
Cl4···H3iv +10.54-12.7-1.2-26.419.8-21.4
Cl1···Cl3iv
Cl3···H7v10.48-3.9-1.3-14.813.4-7.3
C1···H26vi +9.86-37.0-8.0-84.148.4-79.5
C6···H26vi +
C25–H25···Cg(C1–C6)vi +
Cg(C23–C28)···Cg(C23–C28)vi
Symmetry codes: (i) 1 + x, y, z; (ii) 1 - x, - y, 2 - z; (iii) 1 - x, - y, 1 - z; (iv) 2 - x, - y, 1 - z; (v) x, 1 + y, z; (vi) 2 - x, 1 - y, 1 - z.
Summary of interaction energies (kJ mol-1) calculated for (II) top
ContactR (Å)EeleEpolEdisErepEtot
Cg(C9–C14)···Cg(C9–C14)i12.94-0.7-3.0-44.514.8-30.8
Cu···Cl2ii8.13-33.0-5.6-64.144.4-59.0
Cl1···H7iii9.74-3.7-2.5-25.715.4-16.0
C5···C7iv +8.51-14.4-4.7-68.536.8-49.6
Cg(C1–C6)···Cg(C1–C6)iv
Symmetry codes: (i) - x, 1 - y, - z; (ii) 1 + x, y, z; (iii) 1 - x, 1 - y, -z; (iv) 1 - x, - y, 1 - z.
 

Footnotes

Additional correspondence author, e-mail: drmks2000hotmail.com.

Acknowledgements

The authors are thankful to the Department of Chemistry, Saurashtra University, Rajkot, Gujarat, India, for access to the chemical synthesis laboratory, to the Sophisticated Analytical Instrumentation Center (SAIC), Tezpur, Asam, India for providing the X-ray intensity data for (I)[link] and to the Sophisticated Test and Instrumentation Centre (STIC), Kochi, Kerala, India, for the X-ray intensity data for (II)[link].

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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