Crystal structure of trans-di­chlorido­(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4N)chromium(III) bis­(form­amide-κO)(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4N)chromium(III) bis­[tetra­chlorido­zincate(II)]

Moon, D.; Choi, J.-H.

doi:10.1107/S2056989020004910

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ISSN: 2056-9890

Volume 76| Part 5| May 2020| Pages 656-659

https://doi.org/10.1107/S2056989020004910

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Crystal structure of trans-dichlorido(1,4,8,11-tetraazacyclotetradecane-κ⁴N)chromium(III) bis(formamide-κO)(1,4,8,11-tetraazacyclotetradecane-κ⁴N)chromium(III) bis[tetrachloridozincate(II)]

Dohyun Moon ^a and Jong-Ha Choi ^b ^*

^aBeamline Department, Pohang Accelerator Laboratory, POSTECH, Pohang 37673, Republic of Korea, and ^bDepartment of Chemistry, Andong National University, Andong 36729, Republic of Korea
^*Correspondence e-mail: jhchoi@anu.ac.kr

Edited by L. Van Meervelt, Katholieke Universiteit Leuven, Belgium (Received 30 March 2020; accepted 6 April 2020; online 9 April 2020)

The structure of the title compound, [CrCl₂(C₁₀H₂₄N₄)][Cr(HCONH₂)₂(C₁₀H₂₄N₄)][ZnCl₄]₂ (C₁₀H₂₄N₄ = 1,4,8,11-tetraazacyclotetradecane, cyclam; HCONH₂ = formamide, fa), has been determined from synchrotron X-ray data. The asymmetric unit contains two independent halves of the [CrCl₂(cyclam)]⁺ and [Cr(fa)(cyclam)]³⁺ cations, and one tetrachloridozincate anion. In each complex cation, the Cr^III ion is coordinated by the four N atoms of the cyclam ligand in the equatorial plane and two Cl ligands or two O-bonded formamide molecules in a trans axial arrangement, displaying a distorted octahedral geometry with crystallographic inversion symmetry. The Cr—N(cyclam) bond lengths are in the range 2.061 (2) to 2.074 (2) Å, while the Cr—Cl and Cr—O(fa) bond distances are 2.3194 (7) and 1.9953 (19) Å, respectively. The macrocyclic cyclam moieties adopt the centrosymmetric trans-III conformation with six- and five-membered chelate rings in chair and gauche conformations. The crystal structure is stabilized by intermolecular hydrogen bonds involving the NH or CH groups of cyclam and the NH₂ group of coordinated formamide as donors, and Cl atoms of the ZnCl₄²⁻ anion as acceptors.

Keywords: crystal structure; cyclam; chloride; formamide; trans-isomer; chromium(III) complex; synchrotron radiation.

CCDC reference: 1995114

1. Chemical context

The 14-membered cyclam (1,4,8,11-tetraazacyclotetradecane, C₁₀H₂₄N₄) has a moderately flexible structure, and its metal complexes can form either trans or cis-[ML₂(cyclam)]ⁿ⁺ (L = a monodentate ligand) geometric isomers (Poon & Pun, 1980 ). Furthermore, the trans isomer can adopt five conformers, viz. trans-I (+ + + +), trans-II (+ − + +), trans-III (+ − − +), trans-IV (+ + − −) and trans-V (+ − + −), which differ in the chirality of the sec-NH centres (Choi, 2009 ), and where the plus sign indicates the hydrogen atom of the NH group is above the plane of the macrocycle and the minus sign indicates that it is below. The trans-I, trans-II and trans-V conformations can also fold to form cis-I, cis-II and cis-V conformers, respectively (Subhan et al., 2011 ). Recently, it has been shown that cyclam derivatives and their metal complexes exhibit stem-cell mobilization and anti-HIV activity (Ronconi & Sadler, 2007 ; De Clercq, 2010 ; Ross et al., 2012 ). The conformation of the macrocycle and the orientations of the N—H bonds in the complex are very important factors for co-receptor recognition. Therefore, knowledge of the conformation and the crystal packing in transition-metal compounds containing cyclam has become important in the development of new highly effective anti-HIV drugs (De Clercq, 2010). In addition, the formamide group can be coordinated to a metal ion through the oxygen or nitrogen atoms (Balahura & Jordan, 1970 ). It should be noted that the geometric assignment and determination of the coordination mode based on spectroscopic properties is not always conclusive. We describe here the synthesis and structural characterization of a new double complex, [CrCl₂(cyclam)][Cr(fa-O)₂(cyclam)][ZnCl₄]₂, (I), which was performed to elucidate and confirm its molecular structure unambiguously.

2. Structural commentary

Fig. 1 shows a displacement ellipsoid plot of (I) with the atom-numbering scheme. The crystallographic asymmetric unit of (I) is composed of two halves of independent [CrCl₂(cyclam)]⁺ and [Cr(fa)(cyclam)]³⁺ cations and one tetrachloridozincate anion. The two Cr atoms are located on crystallographic centers of symmetry, so these complex cations both have molecular C_i symmetry. Each cyclam moiety in the two Cr^III complex cations adopts the most stable trans-III conformation. The Cr^III ions are six-coordinated in a distorted octahedral geometry with the four N atoms of the macrocyclic ligand in equatorial positions and two Cl ligands or two O atoms of formamide molecules in axial positions (Fig. 1). The Cr—N(cyclam) bond lengths are in the range 2.061 (2) to 2.074 (2) Å, in good agreement with those observed in trans-[Cr(ONO)₂)(cyclam)]BF₄ [2.064 (4)–2.073 (4) Å; De Leo et al., 2000 ], trans-[Cr(NH₃)₂(cyclam)][ZnCl₄]Cl·H₂O [2.0501 (15)–2.0615 (15) Å; Moon & Choi, 2016a ], trans-[Cr(NCS)₂(cyclam)]₂[ZnCl₄] [2.0614 (10)–2.0700 (10) Å; Moon et al., 2015 ], trans-[Cr(NCS)₂(cyclam)]ClO₄ [2.046 (2)–2.060 (2) Å; Friesen et al., 1997 ], trans-[Cr(nic-O)₂(cyclam)]ClO₄ [2.057 (4)–2.064 (4) Å; Choi, 2009], [Cr(ox)(cyclam)]ClO₄ [2.062 (4)–2.085 (5) Å; Choi et al., 2004b ], [Cr(acac)(cyclam)](ClO₄)₂·0.5H₂O [2.065 (5)–2.089 (5) Å; Subhan et al., 2011] and cis-[Cr(ONO)₂(cyclam)]NO₂ [2.0874 (16)–2.0916 (15) Å; Choi et al., 2004a ]. However, the Cr—N bond lengths for the secondary amine of cyclam in the trans isomer are slightly shorter than those of the primary amine found in trans-[CrCl₂(Me₂tn)₂]Cl [2.0861 (18)–2.1076 (18) Å; Choi et al., 2007 ] and trans-[CrCl₂(Me₂tn)₂]₂ZnCl₄ [2.0741 (19)–2.0981 (18) Å; Choi et al., 2011 ]. The Cr—Cl and Cr–O (fa) bond lengths are 2.3194 (7) and 1.9953 (19) Å, respectively. The Cr—Cl distance is comparable to the values in trans-[CrCl₂(cyclam)]Cl [2.3295 (6) Å; Solano-Peralta et al., 2004 ], trans-[CrCl₂(cyclam)]₂[ZnCl₄] [2.3472 (9) Å; Flores-Vélez et al., 1991 ] and [CrCl₂(cyclam)][Cr(ox)(cyclam)](ClO₄)₂ [2.3358 (14) Å; Moon & Choi, 2016b ]. As expected, the five-membered chelate rings adopt a gauche conformation, and the six-membered ring is in the chair conformation. The average bond angles of the five- and six-membered chelate rings around chromium(III) are 85.03 (9) and 94.97 (9)°, respectively. The uncoordinated ZnCl₄²⁻ counter-anion remains outside the coordination sphere of the two Cr^III ions and has a distorted tetrahedral geometry as a result of its involvement in hydrogen-bonding interactions. It exhibits Zn—Cl bond distances in the range 2.2555 (8) to 2.3035 (8) Å and Cl—Zn—Cl angles ranging from 104.84 (4)–114.54 (3)°.

Figure 1
Molecular structure of (I)

, drawn with displacement ellipsoids at the 50% probability level. The primed and double-primed atoms are related by symmetry operations (−x + 1, −y + 1, −z + 1) and (−x + 1, −y + 1, −z), respectively. Hydrogen bonds are shown as dashed lines.

3. Supramolecular features

Extensive C—H⋯Cl and N–H⋯Cl hydrogen-bonding interactions occur between the NH or CH groups of cyclam and the NH₂ group of formamide, the Cl ligand and the Cl atoms of the tetrachlorozincate anion (Table 1). The ZnCl₄²⁻ anion is linked to two [CrCl₂(cyclam)]⁺ and [Cr(fa)(cyclam)]³⁺ cations via a series of N—H⋯Cl and C—H⋯Cl hydrogen bonds. In addition, two Cr^III complex cations are interconnected to each other via a C3—H3A⋯Cl1^vi [symmetry code: (vi) −x + $[{3\over 2}]$ , y + $[{1\over 2}]$ , −z + $[{1\over 2}]$ ] hydrogen bond. The extensive array of these contacts generates a three-dimensional network and helps to consolidate the crystal structure. The crystal packing diagram of (I) viewed perpendicular to the bc plane is shown in Fig. 2.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯Cl4ⁱ	0.99	2.46	3.346 (2)	149
N2—H2⋯Cl3	0.99	2.31	3.255 (2)	159
N3—H3AN⋯Cl5ⁱⁱ	0.87	2.65	3.505 (3)	167
N3—H3BN⋯Cl2ⁱⁱⁱ	0.87	2.61	3.334 (3)	141
C2—H2A⋯Cl2ⁱ	0.98	2.65	3.606 (3)	165
N4—H4⋯Cl3^iv	0.99	2.56	3.493 (2)	157
N5—H5⋯Cl4^v	0.99	2.76	3.549 (2)	137
C3—H3A⋯Cl1^vi	0.98	2.71	3.650 (3)	160
C4—H4A⋯Cl5ⁱⁱ	0.98	2.78	3.555 (3)	136
C7—H7AB⋯Cl2^iv	0.98	2.81	3.738 (3)	159
Symmetry codes: (i) -x+2, -y+1, -z+1; (ii) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (iii) -x+1, -y+1, -z+1; (iv) -x+1, -y+1, -z; (v) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (vi) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Figure 2
Crystal packing of (I)

, viewed along the a axis. Dashed lines represent hydrogen-bonding interactions [N—H⋯Cl (pink) and C—H⋯Cl (green)].

4. Database survey

A search of the Cambridge Structural Database (CSD, Version 5.41, November 2019; Groom et al., 2016 ) indicated 76 hits for a [CrL₂(C₁₀H₂₄N₄)]ⁿ⁺ unit. More than 30 different ligand types L including halogenides, cyanide, azide, thiocyanate, oxalate, ammonia, sulfate, nitrite, DMSO and esters have been reported. It has been found that trans-[Cr(NCS)₂(C₁₀H₂₄N₄)]ClO₄ (RAVGEA; Friesen et al., 1997), trans-[Cr(nic-O)₂(C₁₀H₂₄N₄)]ClO₄ (NUKMUC; Choi, 2009) and trans-[Cr(ONO)₂)(C₁₀H₂₄N₄)]BF₄ (MEMHAN; De Leo et al., 2000) adopt the trans-III conformations. On the other hand, cis-[Cr(NCS)₂(C₁₀H₂₄N₄)]ClO₄ (RAVGOK; Friesen et al., 1997), [Cr(C₂O₄)(C₁₀H₂₄N₄)]ClO₄ (IHAFOM; Choi et al., 2004b), [Cr(CH₃COCHCOCH₃)(C₁₀H₂₄N₄)](ClO₄)₂·0.5H₂O (SAYSES; Subhan et al., 2011) and cis-[Cr(NCS)₂(C₁₀H₂₄N₄)]NCS (ADUXOO; Moon et al., 2013 ) have the folded cis-V conformations. A search of the CSD gave 698 hits for cyclam (C₁₀H₂₄N₄) with any metal but no hit for uncomplexed cyclam. In addition, no compounds containing [Cr(HCONH₂)₂(C₁₀H₂₄N₄)]³⁺ were known until now.

5. Synthesis and crystallization

The free ligand cyclam and formamide were purchased from Sigma–Aldrich. The formamide was purified and dried by standard methods. All other chemicals were reagent-grade materials and used without further purification. The starting material, trans-[Cr(CN)₂(cyclam)]ClO₄, was prepared according to the literature (Kane-Maguire et al., 1983 ). The yellow solid, trans-[Cr(CN)₂(cyclam)]ClO₄ (0.08 g) was dissolved in 5 mL of 0.01 M HCl, and heated for 2 h at 333 K. The solution was added to 3 mL of 6 M HCl containing 0.2 g of solid ZnCl₂, and then 2 mL of formamide were added dropwise under magnetic stirring. The resulting solution was filtered, and allowed to stand at room temperature for a few weeks to give purple crystals of (I) suitable for X-ray structural analysis.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H = 0.94–0.98 Å and N—H = 0.87–0.99 Å and with U_iso(H) = 1.2U_eq(C,N).

Table 2
Experimental details

Crystal data
Chemical formula	[CrCl₂(C₁₀H₂₄N₄)][Cr(CH₃NO)₂(C₁₀H₂₄N₄)][ZnCl₄]₂
M_r	1079.99
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	220
a, b, c (Å)	10.406 (2), 13.212 (3), 15.011 (3)
β (°)	95.85 (3)
V (Å³)	2053.0 (7)
Z	2
Radiation type	Synchrotron, λ = 0.610 Å
μ (mm⁻¹)	1.53
Crystal size (mm)	0.13 × 0.11 × 0.08

Data collection
Diffractometer	Rayonix MX225HS CCD area detector
Absorption correction	Empirical (using intensity measurements) (HKL3000sm SCALEPACK; Otwinowski & Minor, 1997 )
T_min, T_max	0.856, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	20797, 5718, 5424
R_int	0.065
(sin θ/λ)_max (Å⁻¹)	0.693

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.120, 1.08
No. of reflections	5718
No. of parameters	220
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.02, −1.05
Computer programs: PAL BL2D-SMDC (Shin et al., 2016 ), HKL3000sm (Otwinowski & Minor, 1997), SHELXT2018 (Sheldrick, 2015a ), SHELXL2018 (Sheldrick, 2015b ), DIAMOND 4 (Putz & Brandenburg, 2014 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1995114

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989020004910/vm2231sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989020004910/vm2231Isup2.hkl

checkCIF report

Computing details top

Data collection: PAL BL2D-SMDC (Shin et al., 2016); cell refinement: HKL3000sm (Otwinowski & Minor, 1997); data reduction: HKL3000sm (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXT2018 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); molecular graphics: DIAMOND 4 (Putz & Brandenburg, 2014); software used to prepare material for publication: publCIF (Westrip, 2010).

trans-Dichlorido(1,4,8,11-tetraazacyclotetradecane-κ⁴N)chromium(III) bis(formamide-κO)(1,4,8,11-tetraazacyclotetradecane-κ⁴N)chromium(III) bis[tetrachloridozincate(II)] top

Crystal data top

[CrCl₂(C₁₀H₂₄N₄)][Cr(CH₃NO)₂(C₁₀H₂₄N₄)][ZnCl₄]₂	F(000) = 1100
M_r = 1079.99	D_x = 1.747 Mg m⁻³
Monoclinic, P2₁/n	Synchrotron radiation, λ = 0.610 Å
a = 10.406 (2) Å	Cell parameters from 71380 reflections
b = 13.212 (3) Å	θ = 0.4–33.7°
c = 15.011 (3) Å	µ = 1.53 mm⁻¹
β = 95.85 (3)°	T = 220 K
V = 2053.0 (7) Å³	Plate, purple
Z = 2	0.13 × 0.11 × 0.08 mm

Data collection top

Rayonix MX225HS CCD area detector diffractometer	5424 reflections with I > 2σ(I)
Radiation source: PLSII 2D bending magnet	R_int = 0.065
ω scan	θ_max = 25.0°, θ_min = 1.8°
Absorption correction: empirical (using intensity measurements) (HKL3000sm Scalepack; Otwinowski & Minor, 1997)	h = −14→14
T_min = 0.856, T_max = 1.000	k = −18→18
20797 measured reflections	l = −20→20
5718 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.042	H-atom parameters constrained
wR(F²) = 0.120	w = 1/[σ²(F_o²) + (0.0579P)² + 2.3444P] where P = (F_o² + 2F_c²)/3
S = 1.08	(Δ/σ)_max = 0.001
5718 reflections	Δρ_max = 1.02 e Å⁻³
220 parameters	Δρ_min = −1.05 e Å⁻³

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

	x	y	z	U_iso*/U_eq
Cr1	0.500000	0.500000	0.500000	0.01905 (11)
O1	0.40779 (18)	0.59415 (14)	0.57570 (12)	0.0304 (4)
N1	0.6599 (2)	0.50926 (16)	0.59314 (13)	0.0263 (4)
H1	0.733309	0.478812	0.565654	0.032*
N2	0.5477 (2)	0.62362 (15)	0.42632 (14)	0.0270 (4)
H2	0.612781	0.600675	0.387054	0.032*
N3	0.2731 (3)	0.6910 (2)	0.64216 (15)	0.0381 (5)
H3AN	0.332356	0.736628	0.655071	0.046*
H3BN	0.195781	0.699839	0.657996	0.046*
C1	0.6336 (3)	0.4436 (2)	0.66990 (16)	0.0335 (5)
H1A	0.576230	0.478762	0.707614	0.040*
H1AB	0.714487	0.427910	0.706529	0.040*
C2	0.6985 (3)	0.6141 (2)	0.62080 (19)	0.0352 (6)
H2A	0.776779	0.611563	0.662933	0.042*
H2AB	0.629729	0.645040	0.651654	0.042*
C3	0.7237 (3)	0.6793 (2)	0.5405 (2)	0.0399 (6)
H3A	0.768805	0.740799	0.562773	0.048*
H3AB	0.781941	0.642161	0.504919	0.048*
C4	0.6046 (3)	0.7105 (2)	0.4789 (2)	0.0362 (6)
H4A	0.539889	0.738832	0.514956	0.043*
H4AB	0.628599	0.763302	0.437894	0.043*
C5	0.4294 (3)	0.6526 (2)	0.36674 (17)	0.0343 (5)
H5A	0.452908	0.695465	0.317621	0.041*
H5AB	0.369790	0.690444	0.400752	0.041*
C6	0.3001 (3)	0.60960 (19)	0.59923 (15)	0.0280 (5)
H6	0.235060	0.561016	0.585794	0.034*
Cr2	0.500000	0.500000	0.000000	0.02063 (12)
Cl1	0.53785 (6)	0.37596 (5)	−0.10350 (4)	0.03271 (14)
N4	0.3223 (2)	0.52342 (16)	−0.07214 (13)	0.0249 (4)
H4	0.312441	0.470207	−0.118767	0.030*
N5	0.4335 (2)	0.38790 (16)	0.08048 (13)	0.0259 (4)
H5	0.431725	0.324363	0.045410	0.031*
C7	0.3340 (2)	0.62148 (19)	−0.11970 (16)	0.0289 (5)
H7A	0.326491	0.677919	−0.078176	0.035*
H7AB	0.264587	0.627579	−0.168695	0.035*
C8	0.2067 (2)	0.5165 (2)	−0.02153 (17)	0.0307 (5)
H8A	0.128505	0.524049	−0.063273	0.037*
H8AB	0.208634	0.572239	0.021703	0.037*
C9	0.2009 (3)	0.4161 (2)	0.02812 (19)	0.0342 (5)
H9A	0.210352	0.361121	−0.014533	0.041*
H9AB	0.114986	0.409655	0.048899	0.041*
C10	0.3022 (3)	0.4014 (2)	0.10863 (17)	0.0319 (5)
H10A	0.301640	0.460400	0.148121	0.038*
H10B	0.279482	0.341775	0.142624	0.038*
C11	0.5356 (3)	0.3751 (2)	0.15662 (16)	0.0297 (5)
H11A	0.524570	0.310127	0.186461	0.036*
H11B	0.529597	0.429393	0.200469	0.036*
Zn1	0.96538 (3)	0.56371 (2)	0.28510 (2)	0.02620 (9)
Cl2	0.98118 (7)	0.39522 (5)	0.26256 (6)	0.04267 (17)
Cl3	0.74908 (6)	0.60423 (6)	0.27489 (4)	0.03418 (15)
Cl4	1.06521 (7)	0.61932 (6)	0.41833 (4)	0.03892 (16)
Cl5	1.04313 (8)	0.64946 (6)	0.17226 (5)	0.04333 (17)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cr1	0.0141 (2)	0.0235 (2)	0.0203 (2)	−0.00100 (17)	0.00503 (17)	−0.00244 (16)
O1	0.0269 (9)	0.0323 (8)	0.0318 (8)	−0.0007 (7)	0.0021 (7)	−0.0048 (7)
N1	0.0193 (9)	0.0342 (10)	0.0252 (9)	0.0019 (8)	0.0023 (7)	−0.0054 (7)
N2	0.0258 (9)	0.0278 (9)	0.0290 (9)	−0.0009 (8)	0.0112 (8)	−0.0015 (7)
N3	0.0382 (12)	0.0437 (12)	0.0337 (11)	0.0089 (11)	0.0106 (9)	−0.0063 (9)
C1	0.0319 (13)	0.0465 (14)	0.0219 (10)	0.0058 (11)	0.0012 (9)	−0.0015 (9)
C2	0.0252 (12)	0.0393 (13)	0.0396 (13)	−0.0027 (11)	−0.0040 (10)	−0.0118 (11)
C3	0.0270 (12)	0.0382 (13)	0.0551 (16)	−0.0124 (11)	0.0073 (12)	−0.0071 (12)
C4	0.0354 (14)	0.0298 (11)	0.0448 (14)	−0.0075 (11)	0.0120 (11)	−0.0030 (10)
C5	0.0367 (13)	0.0367 (12)	0.0302 (11)	0.0044 (11)	0.0076 (10)	0.0056 (10)
C6	0.0286 (11)	0.0343 (11)	0.0216 (9)	0.0002 (10)	0.0045 (8)	0.0011 (8)
Cr2	0.0185 (2)	0.0252 (2)	0.0181 (2)	0.00430 (18)	0.00144 (18)	−0.00252 (16)
Cl1	0.0330 (3)	0.0374 (3)	0.0274 (3)	0.0097 (3)	0.0014 (2)	−0.0065 (2)
N4	0.0218 (9)	0.0307 (9)	0.0218 (8)	0.0056 (8)	0.0000 (7)	−0.0043 (7)
N5	0.0242 (9)	0.0311 (9)	0.0224 (8)	0.0015 (8)	0.0022 (7)	−0.0003 (7)
C7	0.0258 (11)	0.0338 (11)	0.0264 (10)	0.0108 (10)	−0.0003 (8)	0.0010 (9)
C8	0.0189 (10)	0.0417 (13)	0.0313 (11)	0.0054 (10)	0.0024 (9)	−0.0029 (10)
C9	0.0216 (11)	0.0435 (13)	0.0375 (13)	−0.0062 (11)	0.0029 (10)	−0.0013 (11)
C10	0.0261 (11)	0.0406 (13)	0.0297 (11)	−0.0020 (10)	0.0066 (9)	0.0008 (10)
C11	0.0301 (12)	0.0351 (12)	0.0235 (10)	0.0041 (10)	0.0011 (9)	0.0028 (9)
Zn1	0.02112 (15)	0.03240 (16)	0.02530 (14)	0.00089 (11)	0.00344 (11)	0.00152 (10)
Cl2	0.0293 (3)	0.0332 (3)	0.0636 (4)	0.0034 (3)	−0.0047 (3)	−0.0042 (3)
Cl3	0.0233 (3)	0.0487 (4)	0.0312 (3)	0.0076 (3)	0.0060 (2)	0.0028 (2)
Cl4	0.0373 (3)	0.0493 (4)	0.0288 (3)	0.0094 (3)	−0.0033 (2)	−0.0059 (3)
Cl5	0.0461 (4)	0.0509 (4)	0.0353 (3)	−0.0029 (3)	0.0155 (3)	0.0100 (3)

Geometric parameters (Å, º) top

Cr1—O1	1.9953 (19)	Cr2—N4	2.069 (2)
Cr1—O1ⁱ	1.9954 (19)	Cr2—N4ⁱⁱ	2.069 (2)
Cr1—N2	2.061 (2)	Cr2—N5ⁱⁱ	2.074 (2)
Cr1—N2ⁱ	2.061 (2)	Cr2—N5	2.074 (2)
Cr1—N1ⁱ	2.065 (2)	Cr2—Cl1	2.3194 (7)
Cr1—N1	2.065 (2)	Cr2—Cl1ⁱⁱ	2.3194 (7)
O1—C6	1.226 (3)	N4—C8	1.490 (3)
N1—C1	1.489 (3)	N4—C7	1.490 (3)
N1—C2	1.490 (3)	N4—H4	0.9900
N1—H1	0.9900	N5—C10	1.482 (3)
N2—C4	1.482 (3)	N5—C11	1.488 (3)
N2—C5	1.495 (3)	N5—H5	0.9900
N2—H2	0.9900	C7—C11ⁱⁱ	1.519 (4)
N3—C6	1.299 (3)	C7—H7A	0.9800
N3—H3AN	0.8700	C7—H7AB	0.9800
N3—H3BN	0.8700	C8—C9	1.526 (4)
C1—C5ⁱ	1.509 (4)	C8—H8A	0.9800
C1—H1A	0.9800	C8—H8AB	0.9800
C1—H1AB	0.9800	C9—C10	1.533 (4)
C2—C3	1.525 (4)	C9—H9A	0.9800
C2—H2A	0.9800	C9—H9AB	0.9800
C2—H2AB	0.9800	C10—H10A	0.9800
C3—C4	1.525 (4)	C10—H10B	0.9800
C3—H3A	0.9800	C11—H11A	0.9800
C3—H3AB	0.9800	C11—H11B	0.9800
C4—H4A	0.9800	Zn1—Cl5	2.2555 (8)
C4—H4AB	0.9800	Zn1—Cl2	2.2602 (9)
C5—H5A	0.9800	Zn1—Cl4	2.2792 (9)
C5—H5AB	0.9800	Zn1—Cl3	2.3035 (8)
C6—H6	0.9400

O1—Cr1—O1ⁱ	180.0	N4—Cr2—N4ⁱⁱ	180.0
O1—Cr1—N2	88.14 (8)	N4—Cr2—N5ⁱⁱ	85.50 (8)
O1ⁱ—Cr1—N2	91.86 (8)	N4ⁱⁱ—Cr2—N5ⁱⁱ	94.49 (8)
O1—Cr1—N2ⁱ	91.86 (8)	N4—Cr2—N5	94.49 (8)
O1ⁱ—Cr1—N2ⁱ	88.14 (8)	N4ⁱⁱ—Cr2—N5	85.51 (8)
N2—Cr1—N2ⁱ	180.00 (7)	N5ⁱⁱ—Cr2—N5	180.0
O1—Cr1—N1ⁱ	91.23 (8)	N4—Cr2—Cl1	87.64 (6)
O1ⁱ—Cr1—N1ⁱ	88.77 (8)	N4ⁱⁱ—Cr2—Cl1	92.36 (6)
N2—Cr1—N1ⁱ	84.54 (9)	N5ⁱⁱ—Cr2—Cl1	91.43 (6)
N2ⁱ—Cr1—N1ⁱ	95.46 (9)	N5—Cr2—Cl1	88.57 (6)
O1—Cr1—N1	88.77 (8)	N4—Cr2—Cl1ⁱⁱ	92.36 (6)
O1ⁱ—Cr1—N1	91.23 (8)	N4ⁱⁱ—Cr2—Cl1ⁱⁱ	87.64 (6)
N2—Cr1—N1	95.45 (9)	N5ⁱⁱ—Cr2—Cl1ⁱⁱ	88.57 (6)
N2ⁱ—Cr1—N1	84.54 (9)	N5—Cr2—Cl1ⁱⁱ	91.43 (6)
N1ⁱ—Cr1—N1	180.0	Cl1—Cr2—Cl1ⁱⁱ	180.0
C6—O1—Cr1	140.79 (18)	C8—N4—C7	114.01 (19)
C1—N1—C2	113.0 (2)	C8—N4—Cr2	116.69 (15)
C1—N1—Cr1	106.88 (16)	C7—N4—Cr2	105.58 (15)
C2—N1—Cr1	114.80 (16)	C8—N4—H4	106.6
C1—N1—H1	107.3	C7—N4—H4	106.6
C2—N1—H1	107.3	Cr2—N4—H4	106.6
Cr1—N1—H1	107.3	C10—N5—C11	113.65 (19)
C4—N2—C5	112.3 (2)	C10—N5—Cr2	116.90 (16)
C4—N2—Cr1	115.64 (16)	C11—N5—Cr2	105.93 (15)
C5—N2—Cr1	107.20 (15)	C10—N5—H5	106.6
C4—N2—H2	107.1	C11—N5—H5	106.6
C5—N2—H2	107.1	Cr2—N5—H5	106.6
Cr1—N2—H2	107.1	N4—C7—C11ⁱⁱ	108.69 (19)
C6—N3—H3AN	120.0	N4—C7—H7A	110.0
C6—N3—H3BN	120.0	C11ⁱⁱ—C7—H7A	110.0
H3AN—N3—H3BN	120.0	N4—C7—H7AB	110.0
N1—C1—C5ⁱ	108.4 (2)	C11ⁱⁱ—C7—H7AB	110.0
N1—C1—H1A	110.0	H7A—C7—H7AB	108.3
C5ⁱ—C1—H1A	110.0	N4—C8—C9	112.1 (2)
N1—C1—H1AB	110.0	N4—C8—H8A	109.2
C5ⁱ—C1—H1AB	110.0	C9—C8—H8A	109.2
H1A—C1—H1AB	108.4	N4—C8—H8AB	109.2
N1—C2—C3	111.6 (2)	C9—C8—H8AB	109.2
N1—C2—H2A	109.3	H8A—C8—H8AB	107.9
C3—C2—H2A	109.3	C8—C9—C10	115.9 (2)
N1—C2—H2AB	109.3	C8—C9—H9A	108.3
C3—C2—H2AB	109.3	C10—C9—H9A	108.3
H2A—C2—H2AB	108.0	C8—C9—H9AB	108.3
C4—C3—C2	115.9 (2)	C10—C9—H9AB	108.3
C4—C3—H3A	108.3	H9A—C9—H9AB	107.4
C2—C3—H3A	108.3	N5—C10—C9	111.7 (2)
C4—C3—H3AB	108.3	N5—C10—H10A	109.3
C2—C3—H3AB	108.3	C9—C10—H10A	109.3
H3A—C3—H3AB	107.4	N5—C10—H10B	109.3
N2—C4—C3	111.7 (2)	C9—C10—H10B	109.3
N2—C4—H4A	109.3	H10A—C10—H10B	107.9
C3—C4—H4A	109.3	N5—C11—C7ⁱⁱ	108.09 (19)
N2—C4—H4AB	109.3	N5—C11—H11A	110.1
C3—C4—H4AB	109.3	C7ⁱⁱ—C11—H11A	110.1
H4A—C4—H4AB	107.9	N5—C11—H11B	110.1
N2—C5—C1ⁱ	107.6 (2)	C7ⁱⁱ—C11—H11B	110.1
N2—C5—H5A	110.2	H11A—C11—H11B	108.4
C1ⁱ—C5—H5A	110.2	Cl5—Zn1—Cl2	110.19 (3)
N2—C5—H5AB	110.2	Cl5—Zn1—Cl4	109.31 (3)
C1ⁱ—C5—H5AB	110.2	Cl2—Zn1—Cl4	114.54 (3)
H5A—C5—H5AB	108.5	Cl5—Zn1—Cl3	104.84 (4)
O1—C6—N3	122.1 (3)	Cl2—Zn1—Cl3	107.73 (3)
O1—C6—H6	118.9	Cl4—Zn1—Cl3	109.78 (4)
N3—C6—H6	118.9

C2—N1—C1—C5ⁱ	168.9 (2)	C8—N4—C7—C11ⁱⁱ	171.66 (19)
Cr1—N1—C1—C5ⁱ	41.6 (2)	Cr2—N4—C7—C11ⁱⁱ	42.3 (2)
C1—N1—C2—C3	−179.6 (2)	C7—N4—C8—C9	−178.4 (2)
Cr1—N1—C2—C3	−56.6 (3)	Cr2—N4—C8—C9	−54.8 (2)
N1—C2—C3—C4	72.1 (3)	N4—C8—C9—C10	70.3 (3)
C5—N2—C4—C3	179.0 (2)	C11—N5—C10—C9	179.0 (2)
Cr1—N2—C4—C3	55.5 (3)	Cr2—N5—C10—C9	55.1 (3)
C2—C3—C4—N2	−71.2 (3)	C8—C9—C10—N5	−70.4 (3)
C4—N2—C5—C1ⁱ	−169.7 (2)	C10—N5—C11—C7ⁱⁱ	−171.3 (2)
Cr1—N2—C5—C1ⁱ	−41.6 (2)	Cr2—N5—C11—C7ⁱⁱ	−41.7 (2)
Cr1—O1—C6—N3	−170.2 (2)

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, −y+1, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Cl4ⁱⁱⁱ	0.99	2.46	3.346 (2)	149
N2—H2···Cl3	0.99	2.31	3.255 (2)	159
N3—H3AN···Cl5^iv	0.87	2.65	3.505 (3)	167
N3—H3BN···Cl2ⁱ	0.87	2.61	3.334 (3)	141
C2—H2A···Cl2ⁱⁱⁱ	0.98	2.65	3.606 (3)	165
N4—H4···Cl3ⁱⁱ	0.99	2.56	3.493 (2)	157
N5—H5···Cl4^v	0.99	2.76	3.549 (2)	137
C3—H3A···Cl1^vi	0.98	2.71	3.650 (3)	160
C4—H4A···Cl5^iv	0.98	2.78	3.555 (3)	136
C7—H7AB···Cl2ⁱⁱ	0.98	2.81	3.738 (3)	159

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, −y+1, −z; (iii) −x+2, −y+1, −z+1; (iv) x−1/2, −y+3/2, z+1/2; (v) −x+3/2, y−1/2, −z+1/2; (vi) −x+3/2, y+1/2, −z+1/2.

Funding information

This work was supported by a Research Grant of Andong National University. The X-ray crystallography experiment at the PLS-II BL2D-SMC beamline was supported in part by MSIT and POSTECH.

References

Balahura, R. J. & Jordan, R. B. (1970). J. Am. Chem. Soc. 92, 1533–1539. CrossRef CAS Web of Science Google Scholar
Choi, J.-H. (2009). Inorg. Chim. Acta, 362, 4231–4236. Web of Science CSD CrossRef CAS Google Scholar
Choi, J.-H., Clegg, W., Nichol, G. S., Lee, S. H., Park, Y. C. & Habibi, M. H. (2007). Spectrochim. Acta Part A, 68, 796–801. Web of Science CSD CrossRef Google Scholar
Choi, J.-H., Joshi, T. & Spiccia, L. (2011). Z. Anorg. Allg. Chem. 637, 1194–1198. Web of Science CSD CrossRef CAS Google Scholar
Choi, J.-H., Oh, I.-G., Lim, W.-T. & Park, K.-M. (2004a). Acta Cryst. C60, m238–m240. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Choi, J.-H., Oh, I.-G., Suzuki, T. & Kaizaki, S. (2004b). J. Mol. Struct. 694, 39–44. Web of Science CSD CrossRef CAS Google Scholar
De Clercq, E. (2010). J. Med. Chem. 53, 1438–1450. Web of Science CrossRef PubMed CAS Google Scholar
De Leo, M. A., Bu, X., Bentow, J. & Ford, P. C. (2000). Inorg. Chim. Acta, 300–302, 944–950. Web of Science CSD CrossRef CAS Google Scholar
Flores-Vélez, L. M., Sosa-Rivadeneyra, J., Sosa-Torres, M. E., Rosales-Hoz, M. J. & Toscano, R. A. (1991). J. Chem. Soc. Dalton Trans. pp. 3243–3247. Google Scholar
Friesen, D. A., Quail, J. W., Waltz, W. L. & Nashiem, R. E. (1997). Acta Cryst. C53, 687–691. CSD CrossRef CAS Web of Science IUCr Journals Google Scholar
Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179. Web of Science CrossRef IUCr Journals Google Scholar
Kane-Maguire, N. A. P., Bennett, J. A. & Miller, P. K. (1983). Inorg. Chim. Acta, 76, L123–L125. CAS Google Scholar
Moon, D. & Choi, J.-H. (2016a). Acta Cryst. E72, 456–459. Web of Science CSD CrossRef IUCr Journals Google Scholar
Moon, D. & Choi, J.-H. (2016b). Acta Cryst. E72, 1417–1420. Web of Science CSD CrossRef IUCr Journals Google Scholar
Moon, D., Choi, J.-H., Ryoo, K. S. & Hong, Y. P. (2013). Acta Cryst. E69, m376–m377. CSD CrossRef IUCr Journals Google Scholar
Moon, D., Ryoo, K. S. & Choi, J.-H. (2015). Acta Cryst. E71, 540–543. Web of Science CSD CrossRef IUCr Journals Google Scholar
Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press. Google Scholar
Poon, C.-K. & Pun, K.-C. (1980). Inorg. Chem. 19, 568–569. CrossRef CAS Web of Science Google Scholar
Putz, H. & Brandenburg, K. (2014). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Ronconi, L. & Sadler, P. J. (2007). Coord. Chem. Rev. 251, 1633–1648. Web of Science CrossRef CAS Google Scholar
Ross, A., Choi, J.-H., Hunter, T. M., Pannecouque, C., Moggach, S. A., Parsons, S., De Clercq, E. & Sadler, P. J. (2012). Dalton Trans. 41, 6408–6418. Web of Science CSD CrossRef CAS PubMed Google Scholar
Sheldrick, G. M. (2015a). Acta Cryst. A71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015b). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Shin, J. W., Eom, K. & Moon, D. (2016). J. Synchrotron Rad. 23, 369–373. Web of Science CrossRef IUCr Journals Google Scholar
Solano-Peralta, A., Sosa-Torres, M. E., Flores-Alamo, M., El-Mkami, H., Smith, G. M., Toscano, R. A. & Nakamura, T. (2004). Dalton Trans. pp. 2444–2449. Google Scholar
Subhan, M. A., Choi, J.-H. & Ng, S. W. (2011). Z. Anorg. Allg. Chem. 637, 2193–2197. Web of Science CSD CrossRef CAS Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar

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