Structural characterization of two tetra-chlorido-zincate salts of 4-carb-oxy-1H-imidazol-3-ium: a salt hydrate and a co-crystal salt hydrate.

Imidazole-containing compounds exhibit a myriad of pharmacological activities. Two tetra-chlorido-zincate salts of 4-carb-oxy-1H-imidazol-3-ium, ImHCO2H+, are reported. Bis(4-carb-oxy-1H-imidazol-3-ium) tetra-chlorido-zincate monohydrate, (C4H5N2O2)2[ZnCl4]·H2O, (I), crystallizes as a monohydrate salt, while bis-(4-carb-oxy-1H-imidazol-3-ium) tetra-chlorido-zincate bis-(1H-imidazol-3-ium-4-carboxyl-ato) monohydrate, (C4H5N2O2)2[ZnCl4]·2C4H4N2O2·H2O, (II), is a co-crystal salt with six residues: two ImHCO2H+ cations, two formula units of the zwitterionic 1H-imidazol-3-ium-4-carboxyl-ate, ImHCO2, one tetra-chlorido-zincate anion and one water mol-ecule disordered over two sites in a 0.60 (4):0.40 (4) ratio. The geometric parameters of the ImHCO2H+ and the ImHCO2 moieties are the same within the standard uncertainties of the measurements. Both compounds exhibit extensive hydrogen bonding, including involvement of the tetra-chlorido-zincate anion, resulting in inter-connected chains of anions joined by water mol-ecules.

Chemical context

Imidazole-containing compounds find use in numerous pharmaceuticals including fungicides, anti­viral agents, anti­arrhythmics, anti­histamines, and anthelmintics (Varala et al., 2007 ▸; Horton et al., 2003 ▸; López-Rodríguez et al., 1999 ▸). Recent studies have shown that imidazole and benzimidazole derivatives exhibit pharmacological activity in histamine signaling (Tichenor et al., 2015 ▸; Marson, 2011 ▸), and act as tau aggregation inhibitors for Alzheimer’s disease (Bulic et al., 2013 ▸), and in the central nervous system (Robichaud et al., 2011 ▸; Sheffler et al., 2011 ▸). Further, derivatized imidazole-5-carb­oxy­lic acids have been shown to be angiotensin-converting enzyme (ACE) inhibitors (Jallapally et al., 2015 ▸; Li et al., 1998 ▸; Yanagisawa et al., 1996 ▸).

As a result of the myriad binding modes available to imidazole ligands that bear carb­oxy­lic acid substituents, they have found use in the preparation of several metal organic frameworks, MOFs (Starosta & Leciejewicz, 2006 ▸; Yin et al., 2009 ▸, 2012 ▸; Sun & Yang, 2007 ▸; Sun et al., 2006 ▸). The synthesis and characterization of novel MOFs is an area of active research because of their potential use in such diverse areas as gas storage, catalysis, chemical sensors and mol­ecular separation (Dey et al., 2014 ▸; Kreno et al., 2012 ▸; Farha & Hupp, 2010 ▸). Neutral carb­oxy­imidazoles exist in their zwitterionic form and none of the reported compounds have the carb­oxy­imidazole ligand in the fully protonated form. However, there are examples of MOFs with anionic repeating units and imidazolium cations (Shao & Yu, 2014 ▸; Wang et al., 2013 ▸).

Although the structures of the zwitterionic 1H-imidazol-3-ium-4-carboxyl­ate, (III), (Cao et al., 2012 ▸) and the corresponding 2-isopropyl (Du et al., 2011 ▸) and 2-methyl (Guo, 2009 ▸) derivatives have been reported, to our knowledge, fully protonated imidazole­carb­oxy­lic acid species have not been structurally characterized. Compounds (I) and (II) possess the carb­oxy­imidazole in its fully protonated form and so contribute to the knowledge base of this class of compounds.

Structural commentary

Fig. 1 ▸ shows the atom-labeling scheme employed for (I). The asymmetric unit consists of two 4-carb­oxy-1H-imidazol-3-ium cations (ImHCO2H+), one tetra­chlorido­zincate anion, and one water mol­ecule. Thus, compound (I) is classified as a salt solvate (Grothe et al., 2016 ▸) with four residues.

Figure 1

The mol­ecular structure of (I), showing the atom-labeling scheme. Non-hydrogen anisotropic displacement parameters are drawn at the 50% probability level.

Compound (II) is an example of a rare co-crystal salt solvate with six residues (Grothe et al., 2016 ▸). The asymmetric unit consists of two ImHCO2H+ cations, one tetra­chlorido­zincate anion, two 1H-imidazol-3-ium-4-carboxylate zwitterions (ImHCO2), and one water mol­ecule. The atom-labeling scheme employed is shown in Fig. 2 ▸.

Figure 2

The mol­ecular structure of (II), showing the atom-labeling scheme. Non-hydrogen anisotropic displacement parameters are drawn at the 50% probability level.

The geometric parameters determined for the tetra­chlorido­zincate anions in (I) and (II) are found in Tables 1 ▸ and 2 ▸, respectively. The average Zn—Cl bond length is 2.273 (3) and 2.272 (15) Å, respectively, for (I) and (II), which are within the range 2.2409 (3)–2.3085 (7) Å found in other examples of tetra­chlorido­zincate salts (Govindan et al., 2014a ▸,b ▸; Leesakul et al., 2012 ▸; Goh et al., 2012 ▸; Kefi et al., 2011 ▸). The same example structures exhibit Cl—Zn—Cl angles in the range 102.256 (10) to 112.72 (3)°. The average angles found in (I) and (II) are 109 (2)° and 109 (3)°, respectively, and the individual values exhibit comparable ranges (Tables 1 ▸ and 2 ▸).

Table 1

Selected geometric parameters (Å, °) for (I)

Zn1—Cl2	2.2690 (7)	O1—C1	1.313 (2)
Zn1—Cl3	2.2704 (6)	O2—C1	1.200 (2)
Zn1—Cl4	2.2737 (6)	O3—C5	1.305 (2)
Zn1—Cl1	2.2794 (6)	O4—C5	1.201 (3)
Cl2—Zn1—Cl3	107.93 (2)	Cl3—Zn1—Cl1	112.84 (2)
Cl2—Zn1—Cl4	111.11 (2)	Cl4—Zn1—Cl1	107.92 (2)
Cl3—Zn1—Cl4	109.21 (3)	O2—C1—O1	124.9 (2)
Cl2—Zn1—Cl1	107.85 (2)	O4—C5—O3	125.4 (2)
O2—C1—C2—N1	4.6 (3)	O4—C5—C6—N3	−1.8 (3)

Table 2

Selected geometric parameters (Å, °) for (II)

Zn1—Cl3	2.2577 (12)	O3—C8	1.220 (5)
Zn1—Cl4	2.2589 (11)	O4—C8	1.277 (5)
Zn1—Cl1	2.2758 (12)	O5—C12	1.274 (5)
Zn1—Cl2	2.2948 (12)	O6—C12	1.222 (5)
O1—C4	1.271 (4)	O7—C16	1.224 (5)
O2—C4	1.229 (4)	O8—C16	1.267 (5)
Cl3—Zn1—Cl4	111.21 (4)	Cl1—Zn1—Cl2	108.62 (5)
Cl3—Zn1—Cl1	112.42 (5)	O2—C4—O1	126.3 (4)
Cl4—Zn1—Cl1	109.31 (5)	O3—C8—O4	125.6 (4)
Cl3—Zn1—Cl2	104.23 (5)	O6—C12—O5	126.3 (4)
Cl4—Zn1—Cl2	110.95 (4)	O7—C16—O8	126.3 (4)
N2—C1—C4—O2	5.7 (6)	N5—C9—C12—O6	3.2 (6)
N3—C5—C8—O3	−2.3 (6)	N7—C13—C16—O7	6.3 (6)

There are no noteworthy differences in the C—C and C—N bond lengths between the ImHCO2H+ cations and ImHCO2 zwitterions found in (I) and (II). The N—C′ bond length, where C′ is the carbon atom bonded to both nitro­gen atoms in a given ring (formally, the 2 position in the ring), is consistently shorter than the N—C′′ bond length, where C′′ represents the carbon in the formal 4 or 5 position in the ring, for all of the ImHCO2H+ and ImHCO2 residues. This observation is consistent with other reported imidazoles and imidazolium salts (e.g., Mohamed et al., 2014 ▸; Trifa et al., 2013 ▸; Chérif et al., 2013 ▸; Yu, 2012 ▸; Zhu, 2012 ▸).

The carb­oxy and carboxyl­ate groups are tilted slightly from the imidazole plane in all cases. The N—C—C—O torsion angles are reported in Tables 1 ▸ and 2 ▸. In both (I) and (II), the carb­oxy and carboxyl­ate groups are unsymmetrical. For the carb­oxy groups, the C—OH bond is longer than the C=O bond. These observations are consistent with the geometric parameters found in similar imidazole­carb­oxy­lic acids (Cao et al., 2012 ▸; Du et al., 2011 ▸; Guo, 2009 ▸). The observed O—C—O bond angles of the fully protonated form in (I) and (II) and the zwitterionic form in (II) are the same within the standard uncertainties of the refinement.

Supra­molecular features

An extensive hydrogen-bonding network in (I) involving the tetra­chlorido­zincate anion and the water of hydration results in chains parallel to [20], as seen in Fig. 3 ▸ and Table 3 ▸. Additional Cl⋯H—O—H⋯Cl inter­actions along [100] join the chains (Fig. 4 ▸). N—H⋯O(water), N—H⋯Cl, and O—H⋯O hydrogen bonds incorporate the ImHCO2H+ cations into the three-dimensional extended structure. Using graph-set analysis to describe the hydrogen bonding (Etter et al., 1990 ▸), an (20) ring is observed with four oxygen acceptors, two oxygen donors and two nitro­gen donors. One oxygen donor, two oxygen acceptor rings, (4), involving a carb­oxy group are also present.

Figure 3

Partial packing diagram of (I), showing the water–tetra­chlorido­zincate chains. Only the tetra­chlorido­zincate anion and the water of hydration are shown.

Table 3

Hydrogen-bond geometry (Å, °) for (I)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1S—H1SA⋯Cl2	0.83 (2)	2.42 (2)	3.192 (3)	155 (4)
O1S—H1SB⋯Cl4i	0.81 (2)	2.94 (4)	3.392 (2)	118 (3)
O1S—H1SB⋯Cl1ii	0.81 (2)	3.05 (4)	3.540 (3)	122 (4)
O1—H1A⋯Cl4iii	0.83 (2)	2.25 (2)	3.0723 (19)	171 (3)
O3—H3A⋯O1S iv	0.83 (2)	1.77 (2)	2.576 (3)	163 (3)
N1—H1N⋯Cl1	0.84 (2)	2.37 (2)	3.2105 (17)	178 (2)
N2—H2N⋯Cl1i	0.86 (2)	2.85 (2)	3.3787 (19)	122 (2)
N2—H2N⋯O2i	0.86 (2)	1.99 (2)	2.745 (2)	146 (2)
N3—H3N⋯Cl3v	0.83 (2)	2.37 (2)	3.1941 (18)	177 (2)
N4—H4N⋯Cl3vi	0.86 (2)	2.83 (2)	3.3586 (19)	121 (2)
N4—H4N⋯O4i	0.86 (2)	2.00 (2)	2.753 (2)	146 (2)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) ; (vi) .

Figure 4

Packing diagram of (I), showing the hydrogen-bonding scheme. Only H atoms involved in the inter­actions are shown.

Figs. 5 ▸ and 6 ▸ show two views of the crystal packing observed in (II). Hydrogen-bonding parameters are found in Table 4 ▸. As seen in Fig. 5 ▸, there are several hydrogen-bonding ring motifs that are common to (I) and (II). An (20) ring is observed with four oxygen acceptors, two oxygen donors and two nitro­gen donors, and there is a one oxygen donor, two oxygen acceptor ring, (4), involving a carb­oxy group. (7) rings involving two nitro­gen donors and two oxygen acceptors are also observed. There are two rings containing chlorine acceptor atoms: an (15) system with one oxygen donor, three nitro­gen donors, one oxygen acceptor and three chlorine acceptors; and an (4) ring with a single oxygen donor and two chlorine acceptors. Similarly to (I), chains of hydrogen-bonded tetra­chlorido­zincate anions and water mol­ecules of hydration are found parallel to [20].

Figure 5

A view of the hydrogen bonding in (II), showing the ring motifs. Only H atoms involved in the inter­actions are shown. Only the major contributor to the disorder model of the water mol­ecule is shown.

Figure 6

A second view of the hydrogen bonding in (II). Only H atoms involved in the hydrogen bonds are shown. Only the major contributor to the disorder model of the water mol­ecule is shown.

Table 4

Hydrogen-bond geometry (Å, °) for (II)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O4—H4A⋯O5i	0.87 (2)	1.63 (2)	2.476 (4)	163 (5)
O4—H4A⋯O6i	0.87 (2)	2.52 (4)	3.205 (4)	136 (4)
O8—H8A⋯O1ii	0.85 (2)	1.65 (2)	2.484 (4)	166 (5)
O8—H8A⋯O2ii	0.85 (2)	2.63 (4)	3.162 (4)	122 (4)
O1S—H1A⋯Cl2	0.85 (2)	2.52 (5)	3.330 (9)	159 (10)
O1S—H1B⋯Cl1iii	0.84 (2)	2.97 (9)	3.546 (15)	128 (10)
O1S—H1B⋯Cl4iii	0.84 (2)	2.93 (7)	3.499 (11)	127 (8)
O2S—H2A⋯Cl2	0.85 (2)	2.61 (12)	3.382 (17)	150.20
O2S—H2B⋯Cl1iii	0.85 (2)	2.36 (10)	3.13 (2)	150 (17)
N1—H1N⋯O2iv	0.88 (2)	1.86 (2)	2.712 (4)	160 (4)
N2—H2N⋯Cl2	0.87 (2)	2.44 (2)	3.297 (3)	167 (4)
N3—H3N⋯O1S	0.87 (2)	2.01 (2)	2.860 (10)	168 (4)
N3—H3N⋯O2S	0.87 (2)	1.89 (2)	2.739 (12)	165 (4)
N4—H4N⋯O3iv	0.85 (2)	1.92 (3)	2.677 (5)	148 (4)
N5—H5N⋯Cl4	0.86 (2)	2.39 (2)	3.247 (3)	173 (4)
N6—H6N⋯O6iv	0.87 (2)	1.85 (3)	2.661 (4)	156 (4)
N7—H7N⋯Cl1	0.89 (2)	2.32 (2)	3.205 (3)	175 (4)
N8—H8N⋯O7iv	0.87 (2)	1.78 (2)	2.628 (4)	164 (4)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

In (I), a weak π–π inter­action between ImHCO2H+ cations related by a crystallographically imposed center of symmetry is observed with a centroid-to-centroid distance of 3.5781 (15) Å and an inter­planar distance of 3.4406 (9) Å, corresponding to 0.983 Å slippage (Spek, 2009 ▸). Two independent weak π–π inter­actions between ImHCO2H+ cations and ImHCO2 zwitterions are observed in (II). The principal one involves the rings containing N1 and N7 with a centroid-to-centroid distance of 3.5871 (3) Å, an inter­planar distance of 3.3591 (18) Å and a dihedral angle of 2.6 (2)° between rings (Spek, 2009 ▸). The weaker π–π inter­action involves the rings containing N3 and N5 and has a centroid-to-centroid distance of 3.740 (3) Å, an inter­planar distance of 3.3140 (17) Å and a dihedral angle of 1.2 (2) Å between planes.

Fig. 7 ▸ shows representations of the observed π stacking in which members of inter­acting pairs of mol­ecules are projected into the same plane. A π–π inter­action is also observed in the solid-state structure of the ImHCO2 zwitterion, labeled (III) (Cao et al., 2012 ▸). In (III), the centroid–centroid distance is longer [3.674 (4) Å] than that observed between the fully protonated form in (I) and the principal inter­action between the zwitterion and the protonated form in (II). In all of the pairs except in (I), the members of the pairs are arranged in a head-to-head configuration.

Figure 7

Projections of π-stacked mol­ecules. The mol­ecules are related by the symmetry transformations (I) −x + 1, −y + 1, −z + 1; (IIa) x, y, z; (IIb) x + 1, y − 1,z; (III) x, y, z + 1.

Database survey

The structure of 1-H-imidazol-3-ium-4-carboxyl­ate has been reported (Cao et al., 2012 ▸) and the structures of the 2-methyl and 2-isopropyl derivatives of the zwitterion 5-carb­oxy-1H-3-ium-4-carboxyl­ate monohydrate have been reported (Guo, 2009 ▸; Du et al., 2011 ▸). Several polymeric compounds with bridging 1H-imidazole-4-carboxyl­ato ligands have been reported, including one with CaII (Starosta & Leciejewicz, 2006 ▸) and two with CdII (Yin et al., 2009 ▸, 2012 ▸). The structures of monomeric compounds with 1H-imidazole-4-carboxyl­ato-κ 2 N,O ligands and MgII (Gryz et al., 2007 ▸), MnII (Xiong et al., 2013 ▸), CoII (Chen, 2012 ▸; Artetxe et al., 2013 ▸), NiII (Zheng et al., 2011 ▸), CuII (Reinoso et al., 2015 ▸), and ZnII (Gryz et al., 2007 ▸; He, 2006 ▸; Shuai et al., 2011 ▸) have been determined. Tetra­nuclear MnII complexes with 1H-imidazole-4-carboxyl­ato-κ 2 N,O and the structurally similar 4-imidazole­acetate ligand have also been characterized (Boskovic et al., 2000 ▸). The structures of numerous imidazolium salts are known (e.g., Mohamed et al.,, 2014 ▸; Trifa et al., 2013 ▸; Chérif et al., 2013 ▸; Yu, 2012 ▸; Zhu, 2012 ▸; Ishida & Kashino, 2001 ▸; Gili et al., 2000 ▸; Pavan Kumar & Kumara Swamy, 2005 ▸; Hashizume et al., 2001 ▸; Moreno-Fuquen et al., 2009a ▸,b ▸, 2011 ▸; Zhang et al., 2011 ▸; Sun et al., 2002 ▸; Fukunaga & Ishida, 2003 ▸). There are many examples of reported structures of tetra­chlorido­zincate salts (e.g., Govindan et al., 2014a ▸,b ▸; Leesakul et al., 2012 ▸; Goh et al., 2012 ▸; Kefi et al., 2011 ▸).

Synthesis and crystallization

Compounds (I) and (II) were obtained during the attempted syntheses of ZnII coordination polymers. (I) was obtained by dissolving 113 mg (0.829 mmol) ZnCl2 and 194 mg (1.73 mmol) 1H-imidazole-4-carb­oxy­lic acid in ethanol. Six drops of 6 M HCl were added and the mixture was heated to reflux with stirring. The warm solution was filtered and the filtrate was allowed to cool. After a few days, crystalline clumps of the product were obtained. 1H NMR (400 MHz, dmso-d 6, p.p.m.): 7.97 (s, 2H), 8.51 (s, 2H). 13C NMR (100 MHz, dmso-d 6, p.p.m.): 126.1, 127.4, 137.7, 161.3. A crystal cut from a larger mass of crystals was used for X-ray analysis.

Compound (II) was prepared similarly to (I) except that methanol was the solvent and no HCl was added to the reaction mixture. Single crystals for X-ray analysis were obtained by slow evaporation of a methanol solution.1H NMR (400 MHz, dmso-d 6, p.p.m.): 8.15 (s, 4H), 8.95 (s, 4H). 13C NMR (100 MHz, dmso-d 6, p.p.m.): 125.4, 126.1, 137.6, 160.3.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 5 ▸. For (I), data completeness was 97.9% and for (II) it was 95.2%. For both (I) and (II), all hydrogen atoms were located in difference Fourier maps. The hydrogen atoms bonded to carbon were refined using a riding model with a C—H distance of 0.95 Å and hydrogen-atom isotropic displacement parameters were set using the approximation U iso(H) = 1.2U eq(C). The O—H and N—H distances were restrained to 0.84 and 0.88 Å, respectively. The isotropic displacement parameters of the hydrogen atoms bonded to nitro­gen were set using the approximation U iso(H) = 1.2U eq(N). In (I), isotropic displacement parameters of the hydrogen atoms bonded to oxygen were refined freely, but for (II) they were set using the approximation U iso(H) = 1.5U eq(O). For (II), the water mol­ecule is disordered over two positions. In addition to the aforementioned distance restraint, an H—O—H angle restraint of 105° was employed. The occupancies refined to 0.60 (4):0.40 (4).

Table 5

Experimental details

	(I)	(II)
Crystal data
Chemical formula	(C4H5N2O2)2[ZnCl4]·H2O	(C4H4N2O2)2[ZnCl4]·2C4H5N2O2H2O
M r	451.39	675.57
Crystal system, space group	Triclinic, P	Triclinic, P
Temperature (K)	200	200
a, b, c (Å)	6.9094 (10), 7.5828 (12), 16.468 (3)	6.9369 (19), 6.9624 (15), 28.483 (8)
α, β, γ (°)	79.455 (4), 84.489 (4), 83.833 (4)	89.524 (9), 85.622 (9), 71.202 (8)
V (Å3)	840.7 (2)	1298.3 (6)
Z	2	2
Radiation type	Mo Kα	Mo Kα
μ (mm−1)	2.12	1.42
Crystal size (mm)	0.60 × 0.50 × 0.20	0.50 × 0.25 × 0.20
Data collection
Diffractometer	Bruker SMART X2S benchtop	Bruker SMART X2S benchtop
Absorption correction	Multi-scan (SADABS; Bruker, 2013 ▸)	Multi-scan (SADABS; Bruker, 2013 ▸)
T min, T max	0.41, 0.68	0.50, 0.76
No. of measured, independent and observed [I > 2σ(I)] reflections	10429, 3375, 2995	10560, 4855, 3619
R int	0.032	0.042
(sin θ/λ)max (Å−1)	0.625	0.616
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.024, 0.064, 1.03	0.050, 0.135, 1.03
No. of reflections	3375	4855
No. of parameters	227	395
No. of restraints	8	16
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	0.53, −0.28	0.63, −0.71

Computer programs: APEX2 and SAINT (Bruker, 2013 ▸), SHELXS97 (Sheldrick, 2008 ▸), SHELXL2014 (Sheldrick, 2015 ▸), PLATON (Spek, 2009 ▸), Mercury (Macrae et al., 2006 ▸) and publCIF (Westrip, 2010 ▸).

Crystal structure: contains datablock(s) global, I, II. DOI: 10.1107/S2056989017000317/pj2040sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989017000317/pj2040Isup2.hkl

Click here for additional data file.

Supporting information file. DOI: 10.1107/S2056989017000317/pj2040Isup4.mol

Structure factors: contains datablock(s) II. DOI: 10.1107/S2056989017000317/pj2040IIsup3.hkl

Click here for additional data file.

Supporting information file. DOI: 10.1107/S2056989017000317/pj2040IIsup5.mol

CCDC references: 1526096, 1526095

Additional supporting information: crystallographic information; 3D view; checkCIF report

(C4H5N2O2)2[ZnCl4]·H2O	Z = 2
Mr = 451.39	F(000) = 452
Triclinic, P1	Dx = 1.783 Mg m−3
a = 6.9094 (10) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.5828 (12) Å	Cell parameters from 6894 reflections
c = 16.468 (3) Å	θ = 2.5–27.5°
α = 79.455 (4)°	µ = 2.12 mm−1
β = 84.489 (4)°	T = 200 K
γ = 83.833 (4)°	Plate, clear colourless
V = 840.7 (2) Å3	0.60 × 0.50 × 0.20 mm

Bruker SMART X2S benchtop diffractometer	3375 independent reflections
Radiation source: sealed microfocus tube	2995 reflections with I > 2σ(I)
Doubly curved silicon crystal monochromator	Rint = 0.032
Detector resolution: 8.3330 pixels mm-1	θmax = 26.4°, θmin = 2.5°
ω scans	h = −8→8
Absorption correction: multi-scan (SADABS; Bruker, 2013)	k = −9→9
Tmin = 0.41, Tmax = 0.68	l = −20→19
10429 measured reflections

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.024	Hydrogen site location: mixed
wR(F2) = 0.064	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ2(Fo2) + (0.0292P)2 + 0.2531P] where P = (Fo2 + 2Fc2)/3
3375 reflections	(Δ/σ)max = 0.001
227 parameters	Δρmax = 0.53 e Å−3
8 restraints	Δρmin = −0.28 e Å−3

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.

	x	y	z	Uiso*/Ueq
Zn1	0.24426 (3)	0.35245 (3)	0.23892 (2)	0.03225 (8)
Cl1	0.07702 (7)	0.58951 (7)	0.29003 (3)	0.04037 (13)
Cl2	0.56514 (8)	0.40109 (8)	0.22143 (4)	0.04596 (14)
Cl3	0.14855 (8)	0.32216 (8)	0.11448 (3)	0.04391 (14)
Cl4	0.19391 (9)	0.09768 (8)	0.33224 (3)	0.04754 (14)
O1S	0.7881 (4)	0.0065 (3)	0.25272 (16)	0.0744 (6)
H1SA	0.755 (6)	0.114 (3)	0.256 (2)	0.113 (16)*
H1SB	0.902 (3)	−0.023 (6)	0.241 (3)	0.112 (17)*
O1	0.2088 (3)	0.8341 (3)	0.57654 (11)	0.0583 (5)
H1A	0.096 (3)	0.846 (4)	0.5976 (19)	0.080 (11)*
O2	0.0547 (2)	0.7334 (2)	0.48378 (10)	0.0499 (4)
O3	0.4700 (2)	0.1089 (2)	0.82247 (10)	0.0488 (4)
H3A	0.371 (3)	0.082 (4)	0.8047 (18)	0.068 (9)*
O4	0.2491 (2)	0.1786 (3)	0.92209 (10)	0.0509 (4)
N1	0.4180 (2)	0.6761 (2)	0.39214 (10)	0.0328 (4)
H1N	0.328 (3)	0.656 (3)	0.3653 (13)	0.039*
N2	0.7041 (3)	0.6977 (3)	0.42572 (12)	0.0398 (4)
H2N	0.830 (2)	0.694 (3)	0.4249 (15)	0.048*
N3	0.5549 (2)	0.2595 (2)	1.00903 (11)	0.0354 (4)
H3N	0.448 (3)	0.280 (3)	1.0351 (14)	0.042*
N4	0.8615 (3)	0.2308 (3)	0.97687 (12)	0.0414 (4)
H4N	0.985 (2)	0.234 (3)	0.9774 (16)	0.05*
C1	0.2014 (3)	0.7670 (3)	0.50896 (12)	0.0340 (4)
C2	0.3956 (3)	0.7354 (3)	0.46709 (12)	0.0304 (4)
C3	0.6053 (3)	0.6554 (3)	0.36821 (13)	0.0374 (5)
H3	0.6597	0.6168	0.3185	0.045*
C4	0.5780 (3)	0.7487 (3)	0.48777 (13)	0.0365 (4)
H4	0.6113	0.7864	0.5362	0.044*
C5	0.4145 (3)	0.1639 (3)	0.89239 (12)	0.0352 (4)
C6	0.5806 (3)	0.2008 (3)	0.93398 (12)	0.0320 (4)
C7	0.7275 (3)	0.2773 (3)	1.03332 (14)	0.0404 (5)
H7	0.7507	0.3166	1.0828	0.048*
C8	0.7758 (3)	0.1833 (3)	0.91435 (13)	0.0395 (5)
H8	0.8402	0.1452	0.8661	0.047*

	U11	U22	U33	U12	U13	U23
Zn1	0.03082 (14)	0.03910 (14)	0.02828 (13)	−0.00235 (10)	−0.00091 (9)	−0.01089 (10)
Cl1	0.0302 (3)	0.0506 (3)	0.0444 (3)	0.0027 (2)	−0.0016 (2)	−0.0234 (2)
Cl2	0.0303 (3)	0.0544 (3)	0.0579 (3)	−0.0051 (2)	−0.0010 (2)	−0.0226 (3)
Cl3	0.0329 (3)	0.0699 (4)	0.0337 (3)	−0.0025 (2)	−0.0048 (2)	−0.0219 (2)
Cl4	0.0491 (3)	0.0446 (3)	0.0421 (3)	0.0028 (2)	0.0056 (2)	0.0016 (2)
O1S	0.0736 (16)	0.0632 (14)	0.0966 (17)	0.0020 (12)	−0.0382 (14)	−0.0293 (12)
O1	0.0376 (10)	0.0984 (14)	0.0484 (10)	−0.0049 (9)	−0.0019 (8)	−0.0392 (10)
O2	0.0282 (8)	0.0812 (12)	0.0462 (9)	−0.0099 (8)	−0.0035 (7)	−0.0234 (8)
O3	0.0444 (10)	0.0668 (11)	0.0403 (9)	−0.0072 (8)	−0.0005 (7)	−0.0231 (8)
O4	0.0276 (8)	0.0815 (12)	0.0447 (9)	−0.0031 (8)	−0.0002 (7)	−0.0164 (8)
N1	0.0264 (9)	0.0406 (9)	0.0332 (9)	−0.0024 (7)	−0.0075 (7)	−0.0089 (7)
N2	0.0227 (9)	0.0491 (10)	0.0480 (10)	−0.0037 (8)	−0.0042 (8)	−0.0081 (8)
N3	0.0266 (9)	0.0453 (10)	0.0340 (9)	−0.0015 (8)	0.0024 (7)	−0.0098 (8)
N4	0.0235 (9)	0.0515 (11)	0.0478 (11)	−0.0049 (8)	−0.0014 (8)	−0.0046 (9)
C1	0.0316 (11)	0.0408 (11)	0.0299 (10)	−0.0025 (9)	−0.0045 (8)	−0.0064 (8)
C2	0.0286 (10)	0.0335 (10)	0.0297 (9)	−0.0016 (8)	−0.0055 (8)	−0.0060 (8)
C3	0.0308 (11)	0.0429 (11)	0.0383 (11)	−0.0020 (9)	−0.0016 (9)	−0.0080 (9)
C4	0.0323 (11)	0.0411 (11)	0.0381 (11)	−0.0051 (9)	−0.0085 (9)	−0.0082 (9)
C5	0.0343 (12)	0.0373 (11)	0.0324 (10)	−0.0011 (9)	−0.0016 (8)	−0.0034 (8)
C6	0.0295 (11)	0.0351 (10)	0.0298 (9)	−0.0017 (8)	0.0008 (8)	−0.0043 (8)
C7	0.0330 (12)	0.0484 (12)	0.0410 (11)	−0.0048 (9)	−0.0045 (9)	−0.0094 (10)
C8	0.0310 (11)	0.0479 (12)	0.0369 (11)	−0.0013 (9)	0.0063 (9)	−0.0062 (9)

Zn1—Cl2	2.2690 (7)	N2—C4	1.362 (3)
Zn1—Cl3	2.2704 (6)	N2—H2N	0.864 (16)
Zn1—Cl4	2.2737 (6)	N3—C7	1.321 (3)
Zn1—Cl1	2.2794 (6)	N3—C6	1.378 (2)
O1S—H1SA	0.829 (19)	N3—H3N	0.830 (16)
O1S—H1SB	0.806 (18)	N4—C7	1.316 (3)
O1—C1	1.313 (2)	N4—C8	1.356 (3)
O1—H1A	0.828 (18)	N4—H4N	0.858 (16)
O2—C1	1.200 (2)	C1—C2	1.465 (3)
O3—C5	1.305 (2)	C2—C4	1.355 (3)
O3—H3A	0.827 (17)	C3—H3	0.95
O4—C5	1.201 (3)	C4—H4	0.95
N1—C3	1.317 (3)	C5—C6	1.468 (3)
N1—C2	1.379 (2)	C6—C8	1.354 (3)
N1—H1N	0.838 (16)	C7—H7	0.95
N2—C3	1.323 (3)	C8—H8	0.95
Cl2—Zn1—Cl3	107.93 (2)	O1—C1—C2	112.04 (17)
Cl2—Zn1—Cl4	111.11 (2)	C4—C2—N1	106.33 (17)
Cl3—Zn1—Cl4	109.21 (3)	C4—C2—C1	132.70 (18)
Cl2—Zn1—Cl1	107.85 (2)	N1—C2—C1	120.95 (17)
Cl3—Zn1—Cl1	112.84 (2)	N1—C3—N2	107.86 (18)
Cl4—Zn1—Cl1	107.92 (2)	N1—C3—H3	126.1
H1SA—O1S—H1SB	119 (4)	N2—C3—H3	126.1
C1—O1—H1A	107 (2)	C2—C4—N2	106.69 (18)
C5—O3—H3A	107 (2)	C2—C4—H4	126.7
C3—N1—C2	109.33 (16)	N2—C4—H4	126.7
C3—N1—H1N	124.5 (16)	O4—C5—O3	125.4 (2)
C2—N1—H1N	126.2 (16)	O4—C5—C6	122.53 (18)
C3—N2—C4	109.79 (17)	O3—C5—C6	112.00 (18)
C3—N2—H2N	125.9 (17)	C8—C6—N3	106.23 (18)
C4—N2—H2N	124.3 (17)	C8—C6—C5	132.12 (18)
C7—N3—C6	109.06 (17)	N3—C6—C5	121.61 (17)
C7—N3—H3N	125.3 (17)	N4—C7—N3	107.89 (19)
C6—N3—H3N	125.6 (17)	N4—C7—H7	126.1
C7—N4—C8	110.01 (18)	N3—C7—H7	126.1
C7—N4—H4N	126.0 (17)	C6—C8—N4	106.81 (18)
C8—N4—H4N	123.9 (17)	C6—C8—H8	126.6
O2—C1—O1	124.9 (2)	N4—C8—H8	126.6
O2—C1—C2	123.11 (18)
C3—N1—C2—C4	−0.3 (2)	C7—N3—C6—C8	0.2 (2)
C3—N1—C2—C1	−178.98 (18)	C7—N3—C6—C5	178.29 (19)
O2—C1—C2—C4	−173.6 (2)	O4—C5—C6—C8	175.7 (2)
O1—C1—C2—C4	6.0 (3)	O3—C5—C6—C8	−2.2 (3)
O2—C1—C2—N1	4.6 (3)	O4—C5—C6—N3	−1.8 (3)
O1—C1—C2—N1	−175.81 (19)	O3—C5—C6—N3	−179.68 (18)
C2—N1—C3—N2	0.6 (2)	C8—N4—C7—N3	0.5 (3)
C4—N2—C3—N1	−0.6 (2)	C6—N3—C7—N4	−0.5 (3)
N1—C2—C4—N2	−0.1 (2)	N3—C6—C8—N4	0.1 (2)
C1—C2—C4—N2	178.4 (2)	C5—C6—C8—N4	−177.7 (2)
C3—N2—C4—C2	0.4 (2)	C7—N4—C8—C6	−0.4 (3)

D—H···A	D—H	H···A	D···A	D—H···A
O1S—H1SA···Cl2	0.83 (2)	2.42 (2)	3.192 (3)	155 (4)
O1S—H1SB···Cl4i	0.81 (2)	2.94 (4)	3.392 (2)	118 (3)
O1S—H1SB···Cl1ii	0.81 (2)	3.05 (4)	3.540 (3)	122 (4)
O1—H1A···Cl4iii	0.83 (2)	2.25 (2)	3.0723 (19)	171 (3)
O3—H3A···O1Siv	0.83 (2)	1.77 (2)	2.576 (3)	163 (3)
N1—H1N···Cl1	0.84 (2)	2.37 (2)	3.2105 (17)	178 (2)
N2—H2N···Cl1i	0.86 (2)	2.85 (2)	3.3787 (19)	122 (2)
N2—H2N···O2i	0.86 (2)	1.99 (2)	2.745 (2)	146 (2)
N3—H3N···Cl3v	0.83 (2)	2.37 (2)	3.1941 (18)	177 (2)
N4—H4N···Cl3vi	0.86 (2)	2.83 (2)	3.3586 (19)	121 (2)
N4—H4N···O4i	0.86 (2)	2.00 (2)	2.753 (2)	146 (2)

(C4H4N2O2)2[ZnCl4]·2C4H5N2O2H2O	Z = 2
Mr = 675.57	F(000) = 684
Triclinic, P1	Dx = 1.728 Mg m−3
a = 6.9369 (19) Å	Mo Kα radiation, λ = 0.71073 Å
b = 6.9624 (15) Å	Cell parameters from 3388 reflections
c = 28.483 (8) Å	θ = 3.1–23.6°
α = 89.524 (9)°	µ = 1.42 mm−1
β = 85.622 (9)°	T = 200 K
γ = 71.202 (8)°	Block, clear colourless
V = 1298.3 (6) Å3	0.50 × 0.25 × 0.20 mm

Bruker SMART X2S benchtop diffractometer	4855 independent reflections
Radiation source: sealed microfocus tube	3619 reflections with I > 2σ(I)
Detector resolution: 8.3330 pixels mm-1	Rint = 0.042
ω scans	θmax = 26.0°, θmin = 2.9°
Absorption correction: multi-scan (SADABS; Bruker, 2013)	h = −8→8
Tmin = 0.50, Tmax = 0.76	k = −8→7
10560 measured reflections	l = −35→21

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.050	Hydrogen site location: mixed
wR(F2) = 0.135	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ2(Fo2) + (0.0739P)2 + 0.0203P] where P = (Fo2 + 2Fc2)/3
4855 reflections	(Δ/σ)max < 0.001
395 parameters	Δρmax = 0.63 e Å−3
16 restraints	Δρmin = −0.71 e Å−3

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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
Zn1	−0.05225 (7)	0.61778 (7)	0.24502 (2)	0.03731 (17)
Cl1	−0.26017 (17)	0.82285 (19)	0.19411 (4)	0.0531 (3)
Cl2	0.05785 (16)	0.29226 (16)	0.21504 (3)	0.0436 (3)
Cl3	0.23787 (18)	0.6937 (2)	0.25097 (4)	0.0560 (3)
Cl4	−0.22620 (16)	0.63506 (17)	0.31606 (3)	0.0408 (3)
O1	0.3219 (4)	0.2856 (5)	0.02796 (9)	0.0471 (8)
O2	0.1247 (4)	0.3358 (5)	0.09533 (10)	0.0517 (8)
O3	0.3667 (5)	0.1705 (6)	0.39393 (12)	0.0661 (10)
O4	0.4907 (5)	0.2123 (5)	0.46135 (10)	0.0559 (9)
H4A	0.379 (5)	0.223 (8)	0.4788 (16)	0.084*
O5	−0.1453 (5)	0.7598 (5)	0.50318 (10)	0.0537 (8)
O6	−0.2533 (5)	0.6845 (6)	0.43625 (10)	0.0615 (9)
O7	−0.2136 (5)	0.8281 (6)	0.07375 (11)	0.0685 (10)
O8	−0.0196 (5)	0.7583 (5)	0.00627 (10)	0.0508 (8)
H8A	−0.114 (6)	0.723 (8)	−0.0045 (16)	0.076*
O1S	0.414 (2)	0.099 (2)	0.2899 (6)	0.070 (4)	0.60 (4)
H1A	0.334 (16)	0.176 (12)	0.272 (3)	0.105*	0.60 (4)
H1B	0.459 (16)	−0.021 (6)	0.279 (3)	0.105*	0.60 (4)
O2S	0.495 (5)	0.150 (4)	0.2703 (12)	0.093 (10)	0.40 (4)
H2A	0.381 (15)	0.15 (3)	0.262 (8)	0.14*	0.40 (4)
H2B	0.59 (2)	0.08 (3)	0.251 (5)	0.14*	0.40 (4)
N1	0.7400 (5)	0.3481 (6)	0.12509 (13)	0.0451 (9)
H1N	0.870 (3)	0.342 (7)	0.1225 (15)	0.054*
N2	0.4407 (5)	0.3466 (6)	0.14633 (11)	0.0392 (8)
H2N	0.328 (4)	0.352 (6)	0.1626 (12)	0.047*
N3	0.7314 (6)	0.1382 (5)	0.34378 (11)	0.0405 (8)
H3N	0.644 (5)	0.134 (6)	0.3241 (12)	0.049*
N4	1.0110 (6)	0.1551 (6)	0.36673 (14)	0.0460 (9)
H4N	1.133 (4)	0.158 (7)	0.3638 (15)	0.055*
N5	0.1092 (5)	0.6640 (5)	0.38684 (11)	0.0370 (8)
H5N	0.024 (5)	0.646 (6)	0.3686 (12)	0.044*
N6	0.3850 (5)	0.6882 (6)	0.41028 (12)	0.0437 (9)
H6N	0.511 (4)	0.687 (7)	0.4100 (15)	0.052*
N7	0.1081 (5)	0.8476 (5)	0.12179 (11)	0.0370 (8)
H7N	0.006 (5)	0.834 (6)	0.1409 (12)	0.044*
N8	0.4083 (5)	0.8406 (5)	0.09664 (12)	0.0392 (8)
H8N	0.533 (4)	0.846 (6)	0.0945 (14)	0.047*
C1	0.4601 (6)	0.3304 (6)	0.09817 (12)	0.0317 (9)
C2	0.6497 (6)	0.3318 (6)	0.08465 (14)	0.0403 (10)
H2	0.7095	0.3232	0.0533	0.048*
C3	0.6112 (6)	0.3560 (7)	0.16165 (15)	0.0463 (11)
H3	0.6366	0.3667	0.1937	0.056*
C4	0.2872 (6)	0.3160 (6)	0.07221 (13)	0.0352 (9)
C5	0.7016 (6)	0.1709 (6)	0.39137 (13)	0.0349 (9)
C6	0.8780 (6)	0.1832 (6)	0.40570 (13)	0.0385 (9)
H6	0.9044	0.207	0.437	0.046*
C7	0.9189 (7)	0.1297 (6)	0.32923 (14)	0.0443 (10)
H7	0.9775	0.1092	0.2977	0.053*
C8	0.5038 (7)	0.1835 (6)	0.41683 (14)	0.0412 (10)
C9	0.0765 (6)	0.6982 (6)	0.43471 (12)	0.0332 (9)
C10	0.2521 (6)	0.7147 (6)	0.44949 (13)	0.0411 (10)
H10	0.2774	0.7396	0.4808	0.049*
C11	0.2965 (6)	0.6581 (7)	0.37284 (14)	0.0415 (10)
H11	0.357	0.6361	0.3415	0.05*
C12	−0.1239 (6)	0.7129 (6)	0.45951 (13)	0.0387 (9)
C13	0.1228 (6)	0.8218 (6)	0.07366 (12)	0.0327 (9)
C14	0.3108 (6)	0.8187 (6)	0.05808 (13)	0.0359 (9)
H14	0.3661	0.804	0.0262	0.043*
C15	0.2828 (6)	0.8583 (6)	0.13502 (13)	0.0395 (10)
H15	0.313	0.8756	0.1664	0.047*
C16	−0.0527 (6)	0.8025 (6)	0.04986 (13)	0.0371 (9)

	U11	U22	U33	U12	U13	U23
Zn1	0.0263 (3)	0.0572 (3)	0.0303 (2)	−0.0159 (2)	−0.00276 (18)	0.0010 (2)
Cl1	0.0298 (6)	0.0833 (8)	0.0449 (6)	−0.0162 (6)	−0.0066 (4)	0.0210 (5)
Cl2	0.0350 (6)	0.0569 (7)	0.0396 (5)	−0.0163 (5)	0.0002 (4)	−0.0053 (4)
Cl3	0.0384 (7)	0.0955 (9)	0.0465 (6)	−0.0383 (7)	−0.0061 (5)	0.0008 (6)
Cl4	0.0300 (6)	0.0627 (7)	0.0325 (5)	−0.0195 (5)	0.0005 (4)	−0.0008 (4)
O1	0.0278 (17)	0.083 (2)	0.0384 (15)	−0.0286 (17)	−0.0010 (12)	−0.0070 (14)
O2	0.0223 (16)	0.092 (2)	0.0451 (16)	−0.0247 (17)	0.0012 (12)	−0.0051 (15)
O3	0.034 (2)	0.106 (3)	0.067 (2)	−0.032 (2)	−0.0113 (16)	−0.0099 (19)
O4	0.0332 (19)	0.089 (2)	0.0449 (18)	−0.0209 (19)	0.0054 (13)	−0.0038 (16)
O5	0.0321 (18)	0.090 (2)	0.0411 (16)	−0.0239 (18)	0.0005 (13)	−0.0055 (15)
O6	0.0292 (18)	0.112 (3)	0.0530 (18)	−0.035 (2)	−0.0055 (14)	−0.0124 (18)
O7	0.0241 (18)	0.138 (3)	0.0505 (18)	−0.036 (2)	0.0012 (14)	−0.0083 (19)
O8	0.0326 (18)	0.086 (2)	0.0427 (16)	−0.0312 (18)	−0.0062 (13)	−0.0057 (15)
O1S	0.042 (6)	0.110 (6)	0.048 (6)	−0.008 (5)	−0.014 (5)	−0.020 (4)
O2S	0.060 (14)	0.130 (12)	0.068 (13)	0.008 (11)	−0.035 (11)	−0.019 (11)
N1	0.0172 (19)	0.063 (2)	0.060 (2)	−0.0188 (19)	−0.0057 (16)	−0.0067 (18)
N2	0.0176 (18)	0.060 (2)	0.0417 (18)	−0.0154 (18)	−0.0014 (14)	−0.0019 (16)
N3	0.032 (2)	0.052 (2)	0.0397 (18)	−0.0163 (18)	−0.0075 (15)	0.0016 (16)
N4	0.023 (2)	0.050 (2)	0.069 (2)	−0.0163 (18)	−0.0057 (17)	0.0118 (18)
N5	0.0210 (18)	0.052 (2)	0.0406 (18)	−0.0135 (17)	−0.0100 (14)	−0.0015 (15)
N6	0.0174 (18)	0.060 (2)	0.058 (2)	−0.0166 (18)	−0.0085 (16)	0.0067 (17)
N7	0.0236 (19)	0.056 (2)	0.0353 (17)	−0.0183 (17)	−0.0008 (13)	0.0015 (15)
N8	0.0171 (18)	0.050 (2)	0.056 (2)	−0.0168 (17)	−0.0054 (15)	0.0018 (16)
C1	0.020 (2)	0.040 (2)	0.0378 (19)	−0.0145 (18)	−0.0013 (15)	−0.0030 (16)
C2	0.020 (2)	0.055 (3)	0.044 (2)	−0.011 (2)	0.0009 (16)	−0.0067 (19)
C3	0.028 (2)	0.068 (3)	0.047 (2)	−0.020 (2)	−0.0079 (19)	−0.002 (2)
C4	0.023 (2)	0.045 (2)	0.041 (2)	−0.0149 (19)	−0.0041 (16)	0.0011 (17)
C5	0.031 (2)	0.036 (2)	0.040 (2)	−0.0118 (19)	−0.0084 (17)	0.0009 (17)
C6	0.036 (2)	0.043 (2)	0.040 (2)	−0.015 (2)	−0.0093 (18)	−0.0013 (17)
C7	0.039 (3)	0.050 (3)	0.044 (2)	−0.015 (2)	0.0016 (19)	0.0033 (19)
C8	0.027 (2)	0.049 (3)	0.050 (2)	−0.015 (2)	−0.0047 (18)	−0.0028 (19)
C9	0.020 (2)	0.044 (2)	0.0370 (19)	−0.0120 (19)	−0.0081 (15)	0.0046 (17)
C10	0.031 (2)	0.056 (3)	0.038 (2)	−0.014 (2)	−0.0110 (17)	−0.0017 (18)
C11	0.026 (2)	0.058 (3)	0.042 (2)	−0.015 (2)	−0.0014 (17)	0.0025 (19)
C12	0.025 (2)	0.052 (3)	0.041 (2)	−0.014 (2)	−0.0040 (17)	−0.0012 (18)
C13	0.022 (2)	0.044 (2)	0.0352 (19)	−0.0141 (19)	−0.0042 (15)	0.0015 (16)
C14	0.023 (2)	0.047 (2)	0.038 (2)	−0.013 (2)	−0.0007 (16)	−0.0019 (17)
C15	0.032 (2)	0.052 (3)	0.039 (2)	−0.017 (2)	−0.0118 (17)	0.0020 (18)
C16	0.020 (2)	0.055 (3)	0.039 (2)	−0.015 (2)	−0.0053 (16)	0.0019 (18)

Zn1—Cl3	2.2577 (12)	N4—H4N	0.849 (19)
Zn1—Cl4	2.2589 (11)	N5—C11	1.317 (5)
Zn1—Cl1	2.2758 (12)	N5—C9	1.375 (5)
Zn1—Cl2	2.2948 (12)	N5—H5N	0.858 (19)
O1—C4	1.271 (4)	N6—C11	1.321 (5)
O2—C4	1.229 (4)	N6—C10	1.367 (5)
O3—C8	1.220 (5)	N6—H6N	0.868 (19)
O4—C8	1.277 (5)	N7—C15	1.321 (5)
O4—H4A	0.87 (2)	N7—C13	1.376 (4)
O5—C12	1.274 (5)	N7—H7N	0.889 (19)
O6—C12	1.222 (5)	N8—C15	1.325 (5)
O7—C16	1.224 (5)	N8—C14	1.367 (5)
O8—C16	1.267 (5)	N8—H8N	0.872 (19)
O8—H8A	0.851 (19)	C1—C2	1.345 (5)
O1S—H1A	0.85 (2)	C1—C4	1.487 (5)
O1S—H1B	0.84 (2)	C2—H2	0.95
O2S—H2A	0.85 (2)	C3—H3	0.95
O2S—H2B	0.85 (2)	C5—C6	1.347 (5)
N1—C3	1.309 (5)	C5—C8	1.479 (5)
N1—C2	1.375 (5)	C6—H6	0.95
N1—H1N	0.884 (19)	C7—H7	0.95
N2—C3	1.312 (5)	C9—C10	1.357 (5)
N2—C1	1.370 (5)	C9—C12	1.484 (5)
N2—H2N	0.871 (19)	C10—H10	0.95
N3—C7	1.318 (5)	C11—H11	0.95
N3—C5	1.365 (5)	C13—C14	1.339 (5)
N3—H3N	0.866 (19)	C13—C16	1.481 (5)
N4—C7	1.327 (6)	C14—H14	0.95
N4—C6	1.361 (5)	C15—H15	0.95
Cl3—Zn1—Cl4	111.21 (4)	N1—C3—H3	126.0
Cl3—Zn1—Cl1	112.42 (5)	N2—C3—H3	126.0
Cl4—Zn1—Cl1	109.31 (5)	O2—C4—O1	126.3 (4)
Cl3—Zn1—Cl2	104.23 (5)	O2—C4—C1	117.2 (3)
Cl4—Zn1—Cl2	110.95 (4)	O1—C4—C1	116.5 (3)
Cl1—Zn1—Cl2	108.62 (5)	C6—C5—N3	106.6 (3)
C8—O4—H4A	122 (4)	C6—C5—C8	132.8 (4)
C16—O8—H8A	113 (3)	N3—C5—C8	120.6 (3)
H1A—O1S—H1B	111 (5)	C5—C6—N4	106.8 (3)
H2A—O2S—H2B	113 (6)	C5—C6—H6	126.6
C3—N1—C2	109.4 (3)	N4—C6—H6	126.6
C3—N1—H1N	132 (3)	N3—C7—N4	107.5 (4)
C2—N1—H1N	118 (3)	N3—C7—H7	126.3
C3—N2—C1	109.7 (3)	N4—C7—H7	126.3
C3—N2—H2N	128 (3)	O3—C8—O4	125.6 (4)
C1—N2—H2N	122 (3)	O3—C8—C5	118.2 (4)
C7—N3—C5	109.6 (3)	O4—C8—C5	116.2 (4)
C7—N3—H3N	121 (3)	C10—C9—N5	106.6 (3)
C5—N3—H3N	129 (3)	C10—C9—C12	133.0 (3)
C7—N4—C6	109.4 (4)	N5—C9—C12	120.4 (3)
C7—N4—H4N	120 (3)	C9—C10—N6	106.2 (3)
C6—N4—H4N	130 (3)	C9—C10—H10	126.9
C11—N5—C9	109.5 (3)	N6—C10—H10	126.9
C11—N5—H5N	124 (3)	N5—C11—N6	107.7 (3)
C9—N5—H5N	126 (3)	N5—C11—H11	126.1
C11—N6—C10	110.0 (3)	N6—C11—H11	126.1
C11—N6—H6N	125 (3)	O6—C12—O5	126.3 (4)
C10—N6—H6N	125 (3)	O6—C12—C9	117.6 (3)
C15—N7—C13	109.3 (3)	O5—C12—C9	116.1 (3)
C15—N7—H7N	126 (3)	C14—C13—N7	106.7 (3)
C13—N7—H7N	124 (3)	C14—C13—C16	133.2 (3)
C15—N8—C14	109.4 (3)	N7—C13—C16	120.1 (3)
C15—N8—H8N	128 (3)	C13—C14—N8	107.0 (3)
C14—N8—H8N	122 (3)	C13—C14—H14	126.5
C2—C1—N2	106.3 (3)	N8—C14—H14	126.5
C2—C1—C4	133.6 (3)	N7—C15—N8	107.6 (3)
N2—C1—C4	120.2 (3)	N7—C15—H15	126.2
C1—C2—N1	106.6 (3)	N8—C15—H15	126.2
C1—C2—H2	126.7	O7—C16—O8	126.3 (4)
N1—C2—H2	126.7	O7—C16—C13	117.8 (3)
N1—C3—N2	108.0 (4)	O8—C16—C13	115.9 (3)
C3—N2—C1—C2	−0.4 (5)	C11—N5—C9—C10	0.5 (5)
C3—N2—C1—C4	179.6 (4)	C11—N5—C9—C12	179.7 (4)
N2—C1—C2—N1	0.2 (5)	N5—C9—C10—N6	−0.5 (5)
C4—C1—C2—N1	−179.9 (4)	C12—C9—C10—N6	−179.6 (4)
C3—N1—C2—C1	0.1 (5)	C11—N6—C10—C9	0.4 (5)
C2—N1—C3—N2	−0.4 (5)	C9—N5—C11—N6	−0.2 (5)
C1—N2—C3—N1	0.5 (5)	C10—N6—C11—N5	−0.1 (5)
C2—C1—C4—O2	−174.2 (5)	C10—C9—C12—O6	−177.8 (5)
N2—C1—C4—O2	5.7 (6)	N5—C9—C12—O6	3.2 (6)
C2—C1—C4—O1	5.4 (7)	C10—C9—C12—O5	4.0 (7)
N2—C1—C4—O1	−174.7 (4)	N5—C9—C12—O5	−175.0 (4)
C7—N3—C5—C6	0.3 (5)	C15—N7—C13—C14	−0.4 (5)
C7—N3—C5—C8	−179.0 (4)	C15—N7—C13—C16	179.2 (4)
N3—C5—C6—N4	−0.8 (5)	N7—C13—C14—N8	0.5 (5)
C8—C5—C6—N4	178.4 (4)	C16—C13—C14—N8	−179.0 (4)
C7—N4—C6—C5	1.1 (5)	C15—N8—C14—C13	−0.4 (5)
C5—N3—C7—N4	0.4 (5)	C13—N7—C15—N8	0.1 (5)
C6—N4—C7—N3	−0.9 (5)	C14—N8—C15—N7	0.2 (5)
C6—C5—C8—O3	178.6 (5)	C14—C13—C16—O7	−174.2 (5)
N3—C5—C8—O3	−2.3 (6)	N7—C13—C16—O7	6.3 (6)
C6—C5—C8—O4	0.2 (7)	C14—C13—C16—O8	6.5 (7)
N3—C5—C8—O4	179.3 (4)	N7—C13—C16—O8	−173.0 (4)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4A···O5i	0.87 (2)	1.63 (2)	2.476 (4)	163 (5)
O4—H4A···O6i	0.87 (2)	2.52 (4)	3.205 (4)	136 (4)
O8—H8A···O1ii	0.85 (2)	1.65 (2)	2.484 (4)	166 (5)
O8—H8A···O2ii	0.85 (2)	2.63 (4)	3.162 (4)	122 (4)
O1S—H1A···Cl2	0.85 (2)	2.52 (5)	3.330 (9)	159 (10)
O1S—H1B···Cl1iii	0.84 (2)	2.97 (9)	3.546 (15)	128 (10)
O1S—H1B···Cl4iii	0.84 (2)	2.93 (7)	3.499 (11)	127 (8)
O2S—H2A···Cl2	0.85 (2)	2.61 (12)	3.382 (17)	150.20
O2S—H2B···Cl1iii	0.85 (2)	2.36 (10)	3.13 (2)	150 (17)
N1—H1N···O2iv	0.88 (2)	1.86 (2)	2.712 (4)	160 (4)
N2—H2N···Cl2	0.87 (2)	2.44 (2)	3.297 (3)	167 (4)
N3—H3N···O1S	0.87 (2)	2.01 (2)	2.860 (10)	168 (4)
N3—H3N···O2S	0.87 (2)	1.89 (2)	2.739 (12)	165 (4)
N4—H4N···O3iv	0.85 (2)	1.92 (3)	2.677 (5)	148 (4)
N5—H5N···Cl4	0.86 (2)	2.39 (2)	3.247 (3)	173 (4)
N6—H6N···O6iv	0.87 (2)	1.85 (3)	2.661 (4)	156 (4)
N7—H7N···Cl1	0.89 (2)	2.32 (2)	3.205 (3)	175 (4)
N8—H8N···O7iv	0.87 (2)	1.78 (2)	2.628 (4)	164 (4)
C2—H2···O8v	0.95	2.55	3.414 (5)	152
C3—H3···Cl2iv	0.95	2.91	3.454 (4)	118
C6—H6···O5vi	0.95	2.54	3.400 (5)	151
C7—H7···Cl2iv	0.95	2.77	3.599 (4)	146
C10—H10···O4vi	0.95	2.49	3.345 (5)	151
C11—H11···Cl3	0.95	2.75	3.523 (4)	139
C11—H11···Cl4iv	0.95	2.92	3.528 (4)	123
C14—H14···O1v	0.95	2.47	3.303 (5)	147
C15—H15···Cl3	0.95	2.8	3.511 (4)	132