Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807046764/sj2359sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807046764/sj2359Isup2.hkl |
CCDC reference: 658001
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean (C-C) = 0.006 Å
- R factor = 0.062
- wR factor = 0.174
- Data-to-parameter ratio = 14.7
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT062_ALERT_4_C Rescale T(min) & T(max) by ..................... 1.06 PLAT153_ALERT_1_C The su's on the Cell Axes are Equal (x 100000) 200 Ang. PLAT220_ALERT_2_C Large Non-Solvent N Ueq(max)/Ueq(min) ... 2.71 Ratio
Alert level G ABSTM02_ALERT_3_G When printed, the submitted absorption T values will be replaced by the scaled T values. Since the ratio of scaled T's is identical to the ratio of reported T values, the scaling does not imply a change to the absorption corrections used in the study. Ratio of Tmax expected/reported 1.057 Tmax scaled 0.872 Tmin scaled 0.838 PLAT794_ALERT_5_G Check Predicted Bond Valency for Cu1 (1) 1.22
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 3 ALERT level C = Check and explain 2 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 1 ALERT type 5 Informative message, check
Considerable attention has been paid to tetrazole complexes in recent years, not only because of their structural and topological novelty but also because of their potential applications as molecular-based functional materials in fields such as electrical conductivity, molecular magnetism, molecular absorption, catalysis and optical materials (Demko & Sharpless, 2001; Rodriguez-Dieguez et al., 2007).
A mixture of CuCl2 (0.3 mmol), NaN3 (0.5 mmol), pyrazine-2-carbonitrile (0.3 mmol), 2,2-bipyridine (0.3 mmol) in 3 ml H2O was heated in a 20 ml Teflon-lined reaction vessel at 130°C for two days. After slowly cooling to room temperature over a period of 12 h, blue block-like crystals of (I) were isolated.
All H atoms were located at calculated positions with d(C—H) = 0.93Å and the isotropic displacement parameters refined.
Considerable attention has been paid to the tetrazoles complex in recent years not only because of their structural and topological novelty but also because of their potential applications as molecular-based functional materials in fields such as electrical conductivity, molecular magnetism, molecular absorption, catalysis and optical materials (Demko & Sharpless, 2001; Rodriguez-Dieguez et al., 2007).
The structure of the title tetrazole complex consists of isolated neutral dinuclear units (Fig. 1). The dinuclear unit lies about a center of symmetry and is constructed from two Cu atoms, two 5-pztz- ligands, two bpy ligands and two N3- groups. In the compound, two Cu atoms are bridged through 2-N atoms of the tetrazolide, and the 5-pztz- ligand acts as a tridentate ligand by utilizing its two nitrogen atoms from the tetrazole rings and one nitrogen atom from pyrazine rings to chelate with one Cu2+ ion and bridge another Cu2+ ion. The Cu2+ center is bonded to six nitrogen atoms forming a slightly distorted octahedron, with atoms N1, N4i, N3 and N7 occupying equatorial positions and N2 and N9 in the axial positions. In the crystal structure of (I), the crystal packing is stabilized by intermolecular C—H···N bonds, Table 1.
Considerable attention has been paid to tetrazole complexes in recent years, not only because of their structural and topological novelty but also because of their potential applications as molecular-based functional materials in fields such as electrical conductivity, molecular magnetism, molecular absorption, catalysis and optical materials (Demko & Sharpless, 2001; Rodriguez-Dieguez et al., 2007).
Data collection: RAPID-AUTO (Rigaku, 2004); cell refinement: RAPID-AUTO (Rigaku, 2004); data reduction: RAPID-AUTO (Rigaku, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEX5 (McArdle, 1996); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).
[Cu2(C5H3N6)2(N3)2(C10H8N2)2] | Z = 1 |
Mr = 817.78 | F(000) = 414 |
Triclinic, P1 | Dx = 1.666 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71069 Å |
a = 8.189 (2) Å | Cell parameters from 4727 reflections |
b = 10.252 (2) Å | θ = 6.8–55.1° |
c = 11.380 (2) Å | µ = 1.37 mm−1 |
α = 107.629 (2)° | T = 298 K |
β = 102.061 (2)° | Block, blue |
γ = 108.185 (4)° | 0.1 × 0.1 × 0.1 mm |
V = 815.0 (3) Å3 |
Rigaku R-AXIS SPIDER CCD diffractometer | 3724 independent reflections |
Radiation source: Rotating Anode | 3001 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.084 |
ω oscillation scans | θmax = 27.5°, θmin = 3.4° |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | h = −10→10 |
Tmin = 0.792, Tmax = 0.825 | k = −13→12 |
7984 measured reflections | l = −14→14 |
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)] = 0.062 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.174 | Only H-atom displacement parameters refined |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0895P)2 + ] where P = (Fo2 + 2Fc2)/3 |
3724 reflections | (Δ/σ)max = 0.009 |
254 parameters | Δρmax = 1.44 e Å−3 |
0 restraints | Δρmin = −1.23 e Å−3 |
[Cu2(C5H3N6)2(N3)2(C10H8N2)2] | γ = 108.185 (4)° |
Mr = 817.78 | V = 815.0 (3) Å3 |
Triclinic, P1 | Z = 1 |
a = 8.189 (2) Å | Mo Kα radiation |
b = 10.252 (2) Å | µ = 1.37 mm−1 |
c = 11.380 (2) Å | T = 298 K |
α = 107.629 (2)° | 0.1 × 0.1 × 0.1 mm |
β = 102.061 (2)° |
Rigaku R-AXIS SPIDER CCD diffractometer | 3724 independent reflections |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | 3001 reflections with I > 2σ(I) |
Tmin = 0.792, Tmax = 0.825 | Rint = 0.084 |
7984 measured reflections |
R[F2 > 2σ(F2)] = 0.062 | 0 restraints |
wR(F2) = 0.174 | Only H-atom displacement parameters refined |
S = 1.08 | Δρmax = 1.44 e Å−3 |
3724 reflections | Δρmin = −1.23 e Å−3 |
254 parameters |
Experimental. collimator diameter: 0.800000 mm |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Cu1 | 0.00291 (5) | 0.39768 (4) | 0.13246 (3) | 0.02186 (19) | |
N1 | −0.0628 (4) | 0.2191 (3) | 0.1846 (3) | 0.0228 (6) | |
N2 | 0.1729 (4) | 0.3079 (3) | 0.0730 (2) | 0.0205 (6) | |
N3 | 0.1679 (4) | 0.6080 (3) | 0.1614 (2) | 0.0195 (6) | |
N4 | 0.1678 (4) | 0.6840 (3) | 0.0839 (3) | 0.0213 (6) | |
N5 | 0.2890 (4) | 0.8210 (3) | 0.1493 (3) | 0.0249 (6) | |
N6 | 0.3733 (4) | 0.8393 (3) | 0.2721 (3) | 0.0266 (6) | |
N7 | 0.2331 (4) | 0.5307 (4) | 0.3744 (3) | 0.0275 (7) | |
N8 | 0.5066 (5) | 0.7371 (4) | 0.6118 (3) | 0.0321 (7) | |
N9 | −0.1772 (4) | 0.4647 (3) | 0.1932 (3) | 0.0262 (6) | |
N10 | −0.1322 (5) | 0.5859 (4) | 0.2741 (3) | 0.0311 (7) | |
N11 | −0.0945 (7) | 0.7022 (4) | 0.3530 (4) | 0.0528 (11) | |
C1 | −0.1837 (5) | 0.1860 (4) | 0.2440 (3) | 0.0272 (7) | |
H1 | −0.2643 | 0.2329 | 0.2465 | 0.037 (11)* | |
C2 | −0.1948 (6) | 0.0842 (4) | 0.3025 (3) | 0.0313 (8) | |
H2 | −0.2823 | 0.0618 | 0.3421 | 0.038* | |
C3 | −0.0718 (6) | 0.0168 (4) | 0.3001 (3) | 0.0308 (8) | |
H3 | −0.0747 | −0.0511 | 0.3392 | 0.035 (11)* | |
C4 | 0.0549 (5) | 0.0516 (4) | 0.2391 (3) | 0.0251 (7) | |
H4 | 0.1388 | 0.0080 | 0.2371 | 0.027 (10)* | |
C5 | 0.0553 (5) | 0.1530 (4) | 0.1807 (3) | 0.0222 (7) | |
C6 | 0.1808 (5) | 0.1949 (4) | 0.1098 (3) | 0.0208 (7) | |
C7 | 0.2976 (5) | 0.1272 (4) | 0.0789 (3) | 0.0248 (7) | |
H7 | 0.3023 | 0.0498 | 0.1041 | 0.029 (10)* | |
C8 | 0.4063 (5) | 0.1762 (4) | 0.0106 (3) | 0.0263 (7) | |
H8 | 0.4884 | 0.1345 | −0.0083 | 0.028 (10)* | |
C9 | 0.3925 (5) | 0.2887 (4) | −0.0301 (3) | 0.0284 (8) | |
H9 | 0.4615 | 0.3207 | −0.0791 | 0.034 (11)* | |
C10 | 0.2753 (5) | 0.3506 (4) | 0.0035 (3) | 0.0269 (8) | |
H10 | 0.2663 | 0.4261 | −0.0232 | 0.021 (9)* | |
C11 | 0.2686 (5) | 0.4979 (4) | 0.4791 (3) | 0.0278 (8) | |
H11 | 0.2002 | 0.4032 | 0.4731 | 0.018 (9)* | |
C12 | 0.4035 (5) | 0.5997 (4) | 0.5964 (3) | 0.0301 (8) | |
H12 | 0.4228 | 0.5714 | 0.6667 | 0.032 (11)* | |
C13 | 0.4728 (6) | 0.7708 (4) | 0.5076 (3) | 0.0322 (8) | |
H13 | 0.5422 | 0.8653 | 0.5139 | 0.034 (11)* | |
C14 | 0.3375 (5) | 0.6694 (4) | 0.3902 (3) | 0.0235 (7) | |
C15 | 0.2952 (5) | 0.7063 (4) | 0.2756 (3) | 0.0213 (7) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0287 (3) | 0.0187 (3) | 0.0221 (3) | 0.0138 (2) | 0.0091 (2) | 0.0085 (2) |
N1 | 0.0297 (16) | 0.0177 (14) | 0.0205 (12) | 0.0119 (12) | 0.0073 (11) | 0.0052 (11) |
N2 | 0.0255 (15) | 0.0211 (14) | 0.0162 (11) | 0.0132 (12) | 0.0057 (11) | 0.0059 (11) |
N3 | 0.0286 (15) | 0.0178 (13) | 0.0167 (11) | 0.0133 (12) | 0.0089 (11) | 0.0078 (11) |
N4 | 0.0314 (16) | 0.0177 (14) | 0.0186 (12) | 0.0155 (12) | 0.0090 (11) | 0.0060 (11) |
N5 | 0.0333 (17) | 0.0208 (15) | 0.0224 (13) | 0.0147 (13) | 0.0081 (12) | 0.0076 (12) |
N6 | 0.0337 (17) | 0.0212 (15) | 0.0224 (13) | 0.0119 (13) | 0.0059 (12) | 0.0069 (12) |
N7 | 0.0336 (18) | 0.0262 (16) | 0.0230 (13) | 0.0136 (13) | 0.0074 (12) | 0.0097 (13) |
N8 | 0.0399 (19) | 0.0312 (17) | 0.0197 (13) | 0.0133 (15) | 0.0046 (13) | 0.0078 (13) |
N9 | 0.0315 (17) | 0.0242 (16) | 0.0275 (14) | 0.0147 (13) | 0.0134 (12) | 0.0101 (13) |
N10 | 0.050 (2) | 0.0293 (18) | 0.0293 (15) | 0.0242 (15) | 0.0215 (14) | 0.0172 (15) |
N11 | 0.094 (4) | 0.037 (2) | 0.0405 (18) | 0.036 (2) | 0.035 (2) | 0.0137 (18) |
C1 | 0.032 (2) | 0.0245 (18) | 0.0263 (15) | 0.0150 (15) | 0.0102 (14) | 0.0079 (14) |
C2 | 0.041 (2) | 0.032 (2) | 0.0262 (16) | 0.0176 (17) | 0.0165 (15) | 0.0112 (16) |
C3 | 0.043 (2) | 0.0269 (19) | 0.0274 (16) | 0.0185 (17) | 0.0107 (15) | 0.0141 (15) |
C4 | 0.0315 (19) | 0.0214 (17) | 0.0240 (15) | 0.0146 (15) | 0.0067 (14) | 0.0086 (14) |
C5 | 0.0292 (18) | 0.0173 (16) | 0.0170 (13) | 0.0121 (14) | 0.0051 (12) | 0.0018 (13) |
C6 | 0.0289 (18) | 0.0179 (15) | 0.0141 (12) | 0.0128 (13) | 0.0044 (12) | 0.0030 (12) |
C7 | 0.0321 (19) | 0.0208 (17) | 0.0188 (14) | 0.0141 (14) | 0.0031 (13) | 0.0048 (13) |
C8 | 0.0300 (19) | 0.0259 (18) | 0.0250 (15) | 0.0163 (15) | 0.0098 (14) | 0.0070 (14) |
C9 | 0.036 (2) | 0.0289 (19) | 0.0239 (15) | 0.0154 (16) | 0.0124 (14) | 0.0117 (15) |
C10 | 0.038 (2) | 0.0248 (17) | 0.0258 (15) | 0.0186 (16) | 0.0109 (14) | 0.0133 (15) |
C11 | 0.037 (2) | 0.0272 (19) | 0.0251 (16) | 0.0166 (16) | 0.0117 (15) | 0.0139 (15) |
C12 | 0.036 (2) | 0.036 (2) | 0.0228 (15) | 0.0215 (17) | 0.0102 (14) | 0.0115 (16) |
C13 | 0.037 (2) | 0.030 (2) | 0.0225 (16) | 0.0113 (16) | 0.0033 (15) | 0.0085 (15) |
C14 | 0.0305 (19) | 0.0244 (17) | 0.0162 (13) | 0.0157 (15) | 0.0066 (13) | 0.0048 (13) |
C15 | 0.0272 (18) | 0.0179 (16) | 0.0199 (14) | 0.0121 (14) | 0.0070 (13) | 0.0065 (13) |
Cu1—N9 | 1.974 (3) | C1—H1 | 0.9300 |
Cu1—N2 | 2.014 (3) | C2—C3 | 1.388 (5) |
Cu1—N3 | 2.037 (3) | C2—H2 | 0.9300 |
Cu1—N1 | 2.043 (3) | C3—C4 | 1.380 (5) |
Cu1—N4i | 2.302 (3) | C3—H3 | 0.9300 |
N1—C1 | 1.327 (5) | C4—C5 | 1.392 (5) |
N1—C5 | 1.344 (4) | C4—H4 | 0.9300 |
N2—C10 | 1.333 (5) | C5—C6 | 1.474 (5) |
N2—C6 | 1.360 (4) | C6—C7 | 1.389 (5) |
N3—C15 | 1.333 (4) | C7—C8 | 1.378 (5) |
N3—N4 | 1.343 (4) | C7—H7 | 0.9300 |
N4—N5 | 1.304 (4) | C8—C9 | 1.393 (5) |
N4—Cu1i | 2.302 (3) | C8—H8 | 0.9300 |
N5—N6 | 1.350 (4) | C9—C10 | 1.363 (5) |
N6—C15 | 1.329 (5) | C9—H9 | 0.9300 |
N7—C11 | 1.333 (4) | C10—H10 | 0.9300 |
N7—C14 | 1.344 (5) | C11—C12 | 1.383 (5) |
N8—C13 | 1.331 (4) | C11—H11 | 0.9300 |
N8—C12 | 1.333 (5) | C12—H12 | 0.9300 |
N9—N10 | 1.186 (4) | C13—C14 | 1.384 (5) |
N10—N11 | 1.153 (5) | C13—H13 | 0.9300 |
C1—C2 | 1.388 (5) | C14—C15 | 1.468 (4) |
N9—Cu1—N2 | 173.54 (12) | C3—C4—C5 | 119.0 (3) |
N9—Cu1—N3 | 92.79 (12) | C3—C4—H4 | 120.5 |
N2—Cu1—N3 | 93.43 (12) | C5—C4—H4 | 120.5 |
N9—Cu1—N1 | 93.71 (12) | N1—C5—C4 | 121.3 (3) |
N2—Cu1—N1 | 79.96 (12) | N1—C5—C6 | 115.0 (3) |
N3—Cu1—N1 | 152.23 (11) | C4—C5—C6 | 123.6 (3) |
N9—Cu1—N4i | 92.15 (11) | N2—C6—C7 | 120.7 (3) |
N2—Cu1—N4i | 88.60 (10) | N2—C6—C5 | 114.3 (3) |
N3—Cu1—N4i | 98.96 (10) | C7—C6—C5 | 125.0 (3) |
N1—Cu1—N4i | 107.74 (10) | C8—C7—C6 | 119.1 (3) |
C1—N1—C5 | 119.4 (3) | C8—C7—H7 | 120.5 |
C1—N1—Cu1 | 125.3 (2) | C6—C7—H7 | 120.5 |
C5—N1—Cu1 | 113.7 (2) | C7—C8—C9 | 119.5 (3) |
C10—N2—C6 | 119.2 (3) | C7—C8—H8 | 120.2 |
C10—N2—Cu1 | 125.7 (2) | C9—C8—H8 | 120.2 |
C6—N2—Cu1 | 115.1 (2) | C10—C9—C8 | 118.4 (3) |
C15—N3—N4 | 104.9 (3) | C10—C9—H9 | 120.8 |
C15—N3—Cu1 | 123.4 (2) | C8—C9—H9 | 120.8 |
N4—N3—Cu1 | 131.4 (2) | N2—C10—C9 | 123.0 (3) |
N5—N4—N3 | 109.3 (2) | N2—C10—H10 | 118.5 |
N5—N4—Cu1i | 121.3 (2) | C9—C10—H10 | 118.5 |
N3—N4—Cu1i | 129.3 (2) | N7—C11—C12 | 122.3 (4) |
N4—N5—N6 | 109.7 (3) | N7—C11—H11 | 118.8 |
C15—N6—N5 | 104.4 (3) | C12—C11—H11 | 118.8 |
C11—N7—C14 | 115.6 (3) | N8—C12—C11 | 122.0 (3) |
C13—N8—C12 | 116.2 (3) | N8—C12—H12 | 119.0 |
N10—N9—Cu1 | 121.3 (3) | C11—C12—H12 | 119.0 |
N11—N10—N9 | 177.6 (5) | N8—C13—C14 | 122.0 (4) |
N1—C1—C2 | 122.7 (3) | N8—C13—H13 | 119.0 |
N1—C1—H1 | 118.7 | C14—C13—H13 | 119.0 |
C2—C1—H1 | 118.7 | N7—C14—C13 | 121.9 (3) |
C1—C2—C3 | 118.2 (4) | N7—C14—C15 | 115.4 (3) |
C1—C2—H2 | 120.9 | C13—C14—C15 | 122.6 (3) |
C3—C2—H2 | 120.9 | N6—C15—N3 | 111.7 (3) |
C4—C3—C2 | 119.4 (3) | N6—C15—C14 | 125.5 (3) |
C4—C3—H3 | 120.3 | N3—C15—C14 | 122.8 (3) |
C2—C3—H3 | 120.3 |
Symmetry code: (i) −x, −y+1, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3···N11ii | 0.93 | 2.54 | 3.413 (5) | 157 |
C7—H7···N5ii | 0.93 | 2.52 | 3.450 (4) | 174 |
Symmetry code: (ii) x, y−1, z. |
Experimental details
Crystal data | |
Chemical formula | [Cu2(C5H3N6)2(N3)2(C10H8N2)2] |
Mr | 817.78 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 298 |
a, b, c (Å) | 8.189 (2), 10.252 (2), 11.380 (2) |
α, β, γ (°) | 107.629 (2), 102.061 (2), 108.185 (4) |
V (Å3) | 815.0 (3) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 1.37 |
Crystal size (mm) | 0.1 × 0.1 × 0.1 |
Data collection | |
Diffractometer | Rigaku R-AXIS SPIDER CCD |
Absorption correction | Multi-scan (ABSCOR; Higashi, 1995) |
Tmin, Tmax | 0.792, 0.825 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7984, 3724, 3001 |
Rint | 0.084 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.062, 0.174, 1.08 |
No. of reflections | 3724 |
No. of parameters | 254 |
H-atom treatment | Only H-atom displacement parameters refined |
Δρmax, Δρmin (e Å−3) | 1.44, −1.23 |
Computer programs: RAPID-AUTO (Rigaku, 2004), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEX5 (McArdle, 1996).
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3···N11i | 0.93 | 2.54 | 3.413 (5) | 156.8 |
C7—H7···N5i | 0.93 | 2.52 | 3.450 (4) | 173.9 |
Symmetry code: (i) x, y−1, z. |
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Considerable attention has been paid to the tetrazoles complex in recent years not only because of their structural and topological novelty but also because of their potential applications as molecular-based functional materials in fields such as electrical conductivity, molecular magnetism, molecular absorption, catalysis and optical materials (Demko & Sharpless, 2001; Rodriguez-Dieguez et al., 2007).
The structure of the title tetrazole complex consists of isolated neutral dinuclear units (Fig. 1). The dinuclear unit lies about a center of symmetry and is constructed from two Cu atoms, two 5-pztz- ligands, two bpy ligands and two N3- groups. In the compound, two Cu atoms are bridged through 2-N atoms of the tetrazolide, and the 5-pztz- ligand acts as a tridentate ligand by utilizing its two nitrogen atoms from the tetrazole rings and one nitrogen atom from pyrazine rings to chelate with one Cu2+ ion and bridge another Cu2+ ion. The Cu2+ center is bonded to six nitrogen atoms forming a slightly distorted octahedron, with atoms N1, N4i, N3 and N7 occupying equatorial positions and N2 and N9 in the axial positions. In the crystal structure of (I), the crystal packing is stabilized by intermolecular C—H···N bonds, Table 1.