Poly[μ-chlorido-[μ₄-5-(4-pyrid­yl)tetra­zol­ato]dicopper(I)]

The title three-dimensional coordination polymer, [Cu₂Cl(C₆H₄N₅)]_n, is the product of the hydro­thermal reaction of CuCl₂·2H₂O and 5-(4-pyrid­yl)-1H-tetra­zole (4-Hptz). The two independent Cu^I ions are coordinated in distorted tetra­hedral and distorted trigonal coordination environments. In the unique 5-(4-pyrid­yl)-1H-tetra­zolate ligand, the dihedral angle between the pyridine and tetra­zole rings is 17.3 (2)°.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.009 Å
• R factor = 0.027
• wR factor = 0.092
• Data-to-parameter ratio = 12.3

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Cu1    --  Cl1     ..      16.16 su
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Cu1    --  Cl1_b   ..      16.54 su
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Cu2    --  Cl1     ..      15.64 su

Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR) is > 1.10
            Tmin and Tmax reported:      0.230     0.269
            Tmin and Tmax expected:      0.206     0.267
            RR =      1.107
            Please check that your absorption correction is appropriate.
            Value of measurement temperature given =   298.000
            Value of melting point given =     0.000
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.10
PLAT341_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          9
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.15 Ratio

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.76
           From the CIF: _reflns_number_total               1572
           Count of symmetry unique reflns          960
           Completeness (_total/calc)            163.75%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       612
           Fraction of Friedel pairs measured     0.637
           Are heavy atom types Z>Si present        yes
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          2
PLAT033_ALERT_4_G Flack Parameter Value Deviates from Zero .......       0.19
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        273 K
PLAT804_ALERT_5_G ARU-Pack Problem in PLATON Analysis ............          1 Times

   0 ALERT level A = In general: serious problem
   3 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   5 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   3 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Tetrazoles have found a wide range of applications in areas as diverse as coordination chemistry, medicinal chemistry and materials science (Butler, 1996). The study of complexes containing substituted tetrazole ligands is of interest to delineate the ways in which tetrazoles bind to metal centres. Recently, a series of 5-(4-pyridyl)-1H-tetrazole complexes of transition metals have been reported in which a range of coordination modes for the ligand were observed and extended two-dimensional and three-dimensional structures identified (Xue et al., 2002; Jiang et al., 2004; Luo et al., 2005; Lin et al., 2005; Chen et al., 2008). Herein, we report the crystal structure of a three-dimensional coordination polymer, [Cu^I₂Cl(4-ptz)]_n, derived from 5-(4-pyridyl)-1H-tetrazole and CuCl₂.2H₂O under hydrothermal reaction.

The asymmetric unit of the title complex contains of two independent Cu^I ions, one Cl^-, and one 4-ptz ligand. As shown in Fig. 1, atom Cu1 adopts distorted tetrahedral geometry with a Cl₂N₂ donor set and atom Cu2 is in a disorted trigonal coordination geometry with an N₂Cl donor set. Atom Cl1 is bonded to three Cu^I atoms, and the 4-ptz ligand coordinates to four Cu^I ions. It is noteworthy that atoms N1, N2, and N3 bond to three Cu^I atoms, respectively, forming a µ₃-1,2,3-tetrazolyl coordination mode. The overall structure of title complex is a three-dimensional network (Fig. 2).

Related literature

For related transition metals complexes of 5-(4-pyridyl)-1H-tetrazole, see: Xue et al. (2002); Jiang et al. (2004); Luo et al. (2005); Lin et al. (2005); Chen et al. (2008). For the applications of tetrazoles, see: Butler (1996).

S2. Experimental

A mixture of CuCl₂.2H₂O (0.172 g, 1 mmol), 5-(4-pyridyl)-1H-tetrazole (0.074 g, 0.5 mmol) in 8 ml deionized water was homogenized at room temperature for 30 minutes. Then the final solution was sealed in a 20 mL stainless-steelautoclave at 433 K for 72 h. A quantity of crystals was obtained after the solution was cooled to room temperature. The crystals were filtered, washed with deionized water and dried at room temperature. The yield is ca 64% based on CuCl₂.2H₂O.

S3. Refinement

All H atoms on C atoms were positioned geometrically and allowed to ride on their respective parent atoms, with C—H = 0.93 and U_iso(H) = 1.2 U_eq(C). The crystal is an inversion twin with the ratio of twin components 0.81 (3):0.19 (3).

Computing details

Data collection: APEX2 (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. View of the coordination environment around the Cu^I ions and 4-ptz ligand of title complex with labeling scheme and 30% thermal ellipsoids. Symmetry codes: (i) x, -y + 2, z - 1/2; (ii) x, y + 1, z; (iii) x, y - 1, z; (iv) x - 1/2, y - 1/2, z;(v) x, -y + 2, z + 1/2; (vi) x + 1/2, y + 1/2, z.
	Fig. 2. Part of the crystal structure of the title complex.

Poly[µ-chlorido-[µ₄-5-(4-pyridyl)tetrazolato]dicopper(I)]

Crystal data

[Cu2Cl(C6H4N5)]	F(000) = 600
Mr = 308.67	Dx = 2.517 Mg m^−3
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 1367 reflections
a = 19.6899 (7) Å	θ = 2.1–27.8°
b = 3.6479 (1) Å	µ = 5.50 mm^−1
c = 11.6337 (3) Å	T = 298 K
β = 102.923 (2)°	Block, yellow
V = 814.45 (4) Å^3	0.30 × 0.26 × 0.24 mm
Z = 4

Data collection

Bruker SMART CCD APEXII diffractometer	1572 independent reflections
Radiation source: fine-focus sealed tube	1415 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.027
Detector resolution: 8.40 pixels mm^-1	θmax = 27.8°, θmin = 2.1°
ω scans	h = −21→25
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −4→4
Tmin = 0.230, Tmax = 0.269	l = −15→15
3752 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.027	H-atom parameters constrained
wR(F^2) = 0.092	w = 1/[σ^2(Fo^2) + (0.0547P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.11	(Δ/σ)max < 0.001
1572 reflections	Δρmax = 0.71 e Å^−3
128 parameters	Δρmin = −0.71 e Å^−3
2 restraints	Absolute structure: Flack (1983), 621 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.19 (3)

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cu1	0.17283 (4)	0.9867 (2)	0.16168 (5)	0.0302 (2)
Cu2	0.07924 (5)	0.1504 (3)	0.34304 (8)	0.0341 (2)
Cl1	0.08796 (8)	0.4991 (4)	0.16267 (13)	0.0264 (3)
N1	0.2207 (2)	0.9667 (13)	0.3361 (4)	0.0188 (9)
N2	0.1753 (3)	1.0294 (14)	0.4064 (5)	0.0209 (9)
N3	0.2072 (3)	0.9615 (14)	0.5171 (4)	0.0219 (10)
N4	0.2723 (3)	0.8552 (15)	0.5223 (4)	0.0232 (10)
N5	0.4827 (2)	0.6742 (14)	0.3528 (4)	0.0215 (10)
C1	0.4640 (3)	0.5674 (16)	0.4514 (6)	0.0234 (12)
H1A	0.4971	0.4535	0.5101	0.028*
C2	0.3980 (3)	0.6184 (16)	0.4700 (5)	0.0203 (11)
H2A	0.3876	0.5450	0.5407	0.024*
C3	0.4326 (3)	0.8253 (16)	0.2677 (5)	0.0230 (11)
H3A	0.4446	0.9003	0.1985	0.028*
C4	0.3644 (3)	0.8755 (16)	0.2771 (5)	0.0203 (11)
H4A	0.3312	0.9704	0.2145	0.024*
C5	0.3469 (3)	0.7798 (14)	0.3829 (5)	0.0176 (10)
C6	0.2791 (3)	0.8611 (16)	0.4091 (5)	0.0173 (10)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0279 (4)	0.0496 (4)	0.0144 (3)	−0.0021 (4)	0.0076 (3)	0.0018 (3)
Cu2	0.0125 (3)	0.0561 (5)	0.0334 (4)	0.0066 (4)	0.0042 (3)	0.0033 (4)
Cl1	0.0223 (7)	0.0274 (6)	0.0276 (8)	−0.0018 (5)	0.0016 (6)	0.0035 (5)
N1	0.012 (2)	0.032 (2)	0.012 (2)	0.0020 (18)	0.0023 (17)	0.0003 (18)
N2	0.013 (2)	0.036 (2)	0.014 (2)	0.0013 (19)	0.0042 (16)	−0.001 (2)
N3	0.017 (2)	0.038 (3)	0.011 (2)	0.0014 (19)	0.0038 (18)	−0.0001 (18)
N4	0.018 (2)	0.040 (3)	0.011 (2)	0.004 (2)	0.0035 (18)	0.001 (2)
N5	0.014 (2)	0.028 (2)	0.022 (2)	0.0037 (19)	0.0043 (19)	−0.0005 (19)
C1	0.016 (3)	0.028 (3)	0.025 (3)	0.006 (2)	0.001 (2)	0.006 (2)
C2	0.019 (3)	0.030 (3)	0.012 (3)	0.002 (2)	0.003 (2)	0.002 (2)
C3	0.017 (3)	0.034 (3)	0.018 (3)	0.002 (2)	0.005 (2)	−0.001 (2)
C4	0.021 (3)	0.028 (3)	0.012 (3)	0.004 (2)	0.002 (2)	−0.002 (2)
C5	0.012 (2)	0.023 (2)	0.017 (3)	0.002 (2)	0.002 (2)	−0.0028 (19)
C6	0.014 (2)	0.024 (2)	0.012 (2)	0.000 (2)	0.0001 (19)	−0.002 (2)

Geometric parameters (Å, º)

Cu1—N3^i	1.958 (5)	N4—C6	1.354 (7)
Cu1—N1	2.038 (5)	N5—C1	1.339 (8)
Cu1—Cl1	2.4422 (15)	N5—C3	1.349 (7)
Cu1—Cl1^ii	2.5090 (16)	N5—Cu2^vi	1.931 (4)
Cu2—N2^iii	1.921 (5)	C1—C2	1.377 (8)
Cu2—N5^iv	1.931 (4)	C1—H1A	0.9300
Cu2—Cl1	2.4923 (18)	C2—C5	1.389 (8)
Cl1—Cu1^iii	2.5090 (16)	C2—H2A	0.9300
N1—C6	1.325 (7)	C3—C4	1.383 (8)
N1—N2	1.360 (7)	C3—H3A	0.9300
N2—N3	1.323 (7)	C4—C5	1.395 (8)
N2—Cu2^ii	1.921 (5)	C4—H4A	0.9300
N3—N4	1.327 (7)	C5—C6	1.464 (7)
N3—Cu1^v	1.958 (5)
N3^i—Cu1—N1	133.4 (2)	C1—N5—C3	116.8 (5)
N3^i—Cu1—Cl1	116.27 (15)	C1—N5—Cu2^vi	120.1 (4)
N1—Cu1—Cl1	97.70 (14)	C3—N5—Cu2^vi	122.9 (4)
N3^i—Cu1—Cl1^ii	106.89 (15)	N5—C1—C2	123.1 (5)
N1—Cu1—Cl1^ii	100.51 (13)	N5—C1—H1A	118.5
Cl1—Cu1—Cl1^ii	94.90 (6)	C2—C1—H1A	118.5
N2^iii—Cu2—N5^iv	152.3 (2)	C1—C2—C5	119.8 (5)
N2^iii—Cu2—Cl1	101.13 (17)	C1—C2—H2A	120.1
N5^iv—Cu2—Cl1	106.30 (16)	C5—C2—H2A	120.1
Cu1—Cl1—Cu2	123.48 (7)	N5—C3—C4	124.0 (5)
Cu1—Cl1—Cu1^iii	94.90 (6)	N5—C3—H3A	118.0
Cu2—Cl1—Cu1^iii	78.17 (5)	C4—C3—H3A	118.0
C6—N1—N2	104.9 (5)	C3—C4—C5	118.2 (5)
C6—N1—Cu1	142.2 (4)	C3—C4—H4A	120.9
N2—N1—Cu1	111.9 (4)	C5—C4—H4A	120.9
N3—N2—N1	108.7 (5)	C2—C5—C4	117.9 (5)
N3—N2—Cu2^ii	128.9 (4)	C2—C5—C6	118.6 (5)
N1—N2—Cu2^ii	122.1 (4)	C4—C5—C6	123.4 (5)
N2—N3—N4	110.1 (4)	N1—C6—N4	111.5 (5)
N2—N3—Cu1^v	129.6 (4)	N1—C6—C5	128.8 (5)
N4—N3—Cu1^v	120.3 (4)	N4—C6—C5	119.6 (5)
N3—N4—C6	104.8 (4)

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