catena-Poly[(diaqua­strontium)-bis­{μ-5-[4-(1H-imidazol-1-yl)phen­yl]tetra­zolido}]

Abstract

In the title complex polymer, [Sr(C₁₀H₇N₆)₂(H₂O)₂]_n, the Sr^II atom lies on an inversion centre and is coordinated by four N atoms from two bidentate bridging trans-related 5-[4-(1H-imidazol-1-yl)phen­yl]tetra­zolide ligands [Sr—N = 2.387 (4) Å for the tetrazolide moiety and Sr—N = 2.273 (5) Å for the imidazole moiety], and by two O atoms from water mol­ecules [Sr—O = 2.464 (4) Å], giving a distorted octa­hedral coordination. Pairs of ligand bridges link the complex units, forming chains which extend along [111] and are inter-associated through O_water—H⋯N hydrogen bonds, giving a two-dimensional network structure parallel to (001). Weak π–π stacking inter­actions between the benzene and imidazole rings are also present [minimum ring centroid separation = 3.691 (4) Å].

Related literature  

For our previous work on imidazole derivatives as ligands, see: Tong et al. (2011 ▶); Li et al. (2010 ▶). Wang et al. (2010 ▶). For related structures, see: Huang et al. (2009 ▶); Cheng (2011 ▶).

Experimental  

Crystal data  

• [Sr(C₁₀H₇N₆)₂(H₂O)₂]

• M _r = 546.08

• Triclinic,

• a = 7.6210 (6) Å

• b = 8.0589 (7) Å

• c = 9.1641 (9) Å

• α = 102.783 (1)°

• β = 97.544 (1)°

• γ = 106.036 (2)°

• V = 516.29 (8) ų

• Z = 1

• Mo Kα radiation

• μ = 2.66 mm⁻¹

• T = 298 K

• 0.37 × 0.30 × 0.21 mm

Data collection  

• Bruker SMART CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2007 ▶) T _min = 0.439, T _max = 0.605

• 2616 measured reflections

• 1789 independent reflections

• 1756 reflections with I > 2σ(I)

• R _int = 0.013

Refinement  

• R[F ² > 2σ(F ²)] = 0.036

• wR(F ²) = 0.118

• S = 1.17

• 1789 reflections

• 161 parameters

• H-atom parameters constrained

• Δρ_max = 0.79 e Å⁻³

• Δρ_min = −0.43 e Å⁻³

Data collection: SMART (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; 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: SHELXTL.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1C⋯N1i	0.85	2.07	2.915 (7)	171
O1—H1D⋯N2ii	0.85	2.10	2.948 (6)	171

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

Recently, our research group has shown great interest in the solid-state coordination chemistry of N-heterocyclic carboxylic acids, such as 2-propyl-1H-imidazole-4,5-dicarboxylic acid and 1H-benzimidazole-5,6-dicarboxylic acid. We have synthesized a number of metal complexes using the monoanionic 5-[(4-imidazol-1-yl)phenyl]tetrazolide ligand with a series of metals, e.g. Mn, Cd and Sr (Tong et al., 2011; Li et al., 2010; Wang et al., 2010). In this paper, we report the structure of a new strontium complex with this ligand, obtained under hydrothermal conditions, the title complex polymer, [Sr(C₁₀H₇N₆)₂(H₂O)₂]_n. The centrosymmetric complex molecule (Fig. 1) comprises a Sr^II ion coordinated by four N atoms from the two bidentate bridging trans- related 5-[(4-imidazol-1-yl)phenyl]tetrazolido ligands (two tetrazole and two imidazole) and two O atoms from the water molecules, giving a distorted octahedral stereochemistry [Sr—N = 2.273 (4), 2.387 (5) Å and Sr—O = 2.464 (4) Å]. Duplex bridging ligand molecules link the complex molecules forming polymer chains which extend along [111] and are inter-associated through water O—H···N hydrogen bonds (Table 1) giving a two-dimensional network structure. Weak π–π stacking interactions are also present between the phenyl and the imidazole rings [minimum ring centroid separation, 3.691 (4) Å]. The structures of similar complexes are also known (Huang et al., 2009; Cheng, 2011).

Experimental

A mixture of strontium chloride (0.1 mmol, 0.027 g) and 5-[4-imidazol-1-yl)phenyl]tetrazole (0.2 mmol, 0.043 g) in 12 ml of water was sealed in an autoclave equipped with a Teflon liner (25 ml) and then heated at 413 K for 3 days. Crystals of the title compound were obtained by slow evaporation of the solvent at room temperature.

Refinement

H atoms of the water molecule were located in a difference-Fourier map and refined as riding with an O—H distance restraint of 0.85 Å, with U_iso(H) = 1.2 U_eq(O). The imidazolyl and phenyl H atoms were located in a difference-Fourier but were refined as riding with C—H = 0.93 Å also with U_iso(H) = 1.2U_eq(C).

Figures

Fig. 1.

Molecular configuration and atom numbering scheme for the title complex showing 30% probability ellipsoids. For symmetry codes: (i) x + 1, y + 1, z + 1; (ii) -x, -y, -z; (iii) -x + 1, -y + 1, -z + 1.

Crystal data

[Sr(C10H7N6)2(H2O)2]	Z = 1
Mr = 546.08	F(000) = 276
Triclinic, P1	Dx = 1.756 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.6210 (6) Å	Cell parameters from 2869 reflections
b = 8.0589 (7) Å	θ = 2.8–28.3°
c = 9.1641 (9) Å	µ = 2.66 mm−1
α = 102.783 (1)°	T = 298 K
β = 97.544 (1)°	Block, colourless
γ = 106.036 (2)°	0.37 × 0.30 × 0.21 mm
V = 516.29 (8) Å3

Data collection

Bruker SMART CCD area-detector diffractometer	1789 independent reflections
Radiation source: fine-focus sealed tube	1756 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.013
φ and ω scans	θmax = 25.0°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −9→9
Tmin = 0.439, Tmax = 0.605	k = −9→7
2616 measured reflections	l = −10→9

Refinement

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.036	H-atom parameters constrained
wR(F2) = 0.118	w = 1/[σ2(Fo2) + (0.0473P)2 + 1.6581P] where P = (Fo2 + 2Fc2)/3
S = 1.17	(Δ/σ)max < 0.001
1789 reflections	Δρmax = 0.79 e Å−3
161 parameters	Δρmin = −0.43 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.260 (15)

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

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
Sr1	0.50000	0.50000	0.50000	0.0271 (2)
O1	0.3110 (6)	0.2631 (5)	0.5968 (5)	0.0511 (12)
N1	−0.0566 (7)	−0.7449 (6)	−0.3419 (5)	0.0468 (16)
N2	−0.2033 (7)	−0.8777 (6)	−0.4402 (6)	0.0478 (16)
N3	−0.3273 (6)	−0.8089 (6)	−0.4930 (6)	0.0480 (16)
N4	−0.2656 (6)	−0.6290 (6)	−0.4306 (5)	0.0451 (14)
N5	0.3031 (6)	0.1033 (6)	0.0479 (5)	0.0411 (12)
N6	0.4352 (6)	0.3262 (6)	0.2555 (5)	0.0435 (14)
C1	−0.0992 (7)	−0.5942 (7)	−0.3381 (6)	0.0402 (17)
C2	0.0161 (7)	−0.4150 (7)	−0.2417 (6)	0.0418 (17)
C3	0.1352 (8)	−0.3925 (8)	−0.1057 (7)	0.0477 (17)
C4	0.2324 (8)	−0.2232 (7)	−0.0114 (7)	0.0481 (17)
C5	0.2105 (7)	−0.0735 (7)	−0.0516 (6)	0.0403 (17)
C6	0.0955 (8)	−0.0935 (7)	−0.1875 (6)	0.0473 (17)
C7	−0.0003 (8)	−0.2634 (7)	−0.2825 (6)	0.0454 (17)
C8	0.3753 (8)	0.1501 (7)	0.1989 (6)	0.0433 (17)
C9	0.4015 (8)	0.3956 (7)	0.1358 (6)	0.0460 (17)
C10	0.3208 (8)	0.2604 (7)	0.0071 (6)	0.0475 (17)
H1C	0.20900	0.27310	0.61930	0.0610*
H1D	0.29230	0.15410	0.55030	0.0610*
H3	0.14980	−0.49270	−0.07760	0.0580*
H4	0.31260	−0.21000	0.07910	0.0570*
H6	0.08210	0.00710	−0.21560	0.0570*
H7	−0.07670	−0.27600	−0.37480	0.0540*
H8	0.38200	0.06900	0.25590	0.0520*
H9	0.42970	0.51710	0.14180	0.0550*
H10	0.28420	0.27160	−0.09020	0.0570*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Sr1	0.0303 (4)	0.0239 (4)	0.0238 (4)	0.0093 (2)	0.0006 (2)	0.0018 (2)
O1	0.049 (2)	0.043 (2)	0.061 (2)	0.0155 (17)	0.0138 (19)	0.0107 (18)
N1	0.046 (3)	0.043 (2)	0.050 (3)	0.016 (2)	0.007 (2)	0.009 (2)
N2	0.049 (3)	0.036 (2)	0.054 (3)	0.013 (2)	0.007 (2)	0.006 (2)
N3	0.044 (3)	0.038 (2)	0.057 (3)	0.012 (2)	0.004 (2)	0.008 (2)
N4	0.044 (2)	0.036 (2)	0.049 (3)	0.0105 (19)	0.004 (2)	0.0048 (19)
N5	0.045 (2)	0.040 (2)	0.037 (2)	0.0126 (19)	0.0065 (19)	0.0099 (18)
N6	0.048 (3)	0.039 (2)	0.039 (2)	0.012 (2)	0.0053 (19)	0.0061 (19)
C1	0.039 (3)	0.041 (3)	0.041 (3)	0.015 (2)	0.008 (2)	0.009 (2)
C2	0.039 (3)	0.044 (3)	0.042 (3)	0.014 (2)	0.010 (2)	0.009 (2)
C3	0.049 (3)	0.042 (3)	0.051 (3)	0.018 (2)	0.001 (3)	0.011 (2)
C4	0.049 (3)	0.046 (3)	0.045 (3)	0.017 (2)	−0.002 (2)	0.008 (2)
C5	0.040 (3)	0.042 (3)	0.038 (3)	0.012 (2)	0.010 (2)	0.009 (2)
C6	0.055 (3)	0.039 (3)	0.044 (3)	0.010 (2)	0.004 (2)	0.013 (2)
C7	0.048 (3)	0.044 (3)	0.038 (3)	0.009 (2)	0.003 (2)	0.009 (2)
C8	0.051 (3)	0.039 (3)	0.039 (3)	0.015 (2)	0.005 (2)	0.010 (2)
C9	0.056 (3)	0.039 (3)	0.042 (3)	0.013 (2)	0.008 (2)	0.013 (2)
C10	0.061 (3)	0.041 (3)	0.038 (3)	0.013 (3)	0.006 (2)	0.012 (2)

Geometric parameters (Å, º)

Sr1—O1	2.464 (4)	N6—C9	1.363 (7)
Sr1—N6	2.273 (4)	C1—C2	1.473 (8)
Sr1—N4i	2.387 (5)	C2—C7	1.387 (8)
Sr1—N4ii	2.387 (5)	C2—C3	1.386 (8)
Sr1—O1iii	2.464 (4)	C3—C4	1.382 (9)
Sr1—N6iii	2.273 (4)	C4—C5	1.382 (8)
O1—H1C	0.8500	C5—C6	1.375 (8)
O1—H1D	0.8500	C6—C7	1.385 (8)
N1—N2	1.362 (7)	C9—C10	1.352 (8)
N1—C1	1.336 (8)	C3—H3	0.9300
N2—N3	1.313 (7)	C4—H4	0.9300
N3—N4	1.355 (7)	C6—H6	0.9300
N4—C1	1.350 (7)	C7—H7	0.9300
N5—C8	1.347 (7)	C8—H8	0.9300
N5—C10	1.375 (7)	C9—H9	0.9300
N5—C5	1.435 (7)	C10—H10	0.9300
N6—C8	1.321 (7)
O1—Sr1—N6	94.69 (16)	N1—C1—N4	110.9 (5)
O1—Sr1—N4i	81.30 (16)	N4—C1—C2	124.4 (5)
O1—Sr1—N4ii	98.70 (16)	N1—C1—C2	124.7 (5)
O1—Sr1—O1iii	180.00	C3—C2—C7	118.4 (5)
O1—Sr1—N6iii	85.31 (16)	C1—C2—C7	119.8 (5)
N4i—Sr1—N6	90.56 (16)	C1—C2—C3	121.7 (5)
N4ii—Sr1—N6	89.44 (16)	C2—C3—C4	120.9 (6)
O1iii—Sr1—N6	85.31 (16)	C3—C4—C5	120.0 (6)
N6—Sr1—N6iii	180.00	N5—C5—C4	121.0 (5)
N4i—Sr1—N4ii	180.00	N5—C5—C6	119.2 (5)
O1iii—Sr1—N4i	98.70 (16)	C4—C5—C6	119.8 (5)
N4i—Sr1—N6iii	89.44 (16)	C5—C6—C7	120.0 (5)
O1iii—Sr1—N4ii	81.30 (16)	C2—C7—C6	120.9 (5)
N4ii—Sr1—N6iii	90.56 (16)	N5—C8—N6	111.2 (5)
O1iii—Sr1—N6iii	94.69 (16)	N6—C9—C10	109.4 (5)
H1C—O1—H1D	108.00	N5—C10—C9	106.7 (5)
Sr1—O1—H1D	119.00	C2—C3—H3	120.00
Sr1—O1—H1C	118.00	C4—C3—H3	120.00
N2—N1—C1	105.0 (5)	C3—C4—H4	120.00
N1—N2—N3	109.8 (5)	C5—C4—H4	120.00
N2—N3—N4	108.9 (5)	C5—C6—H6	120.00
N3—N4—C1	105.5 (5)	C7—C6—H6	120.00
Sr1iv—N4—N3	110.5 (3)	C2—C7—H7	120.00
Sr1iv—N4—C1	143.5 (4)	C6—C7—H7	120.00
C8—N5—C10	106.5 (5)	N5—C8—H8	124.00
C5—N5—C8	128.0 (5)	N6—C8—H8	124.00
C5—N5—C10	125.3 (4)	N6—C9—H9	125.00
Sr1—N6—C8	131.1 (4)	C10—C9—H9	125.00
Sr1—N6—C9	120.4 (4)	N5—C10—H10	127.00
C8—N6—C9	106.2 (4)	C9—C10—H10	127.00
O1—Sr1—N6—C8	−20.5 (5)	C10—N5—C8—N6	0.7 (7)
O1—Sr1—N6—C9	139.5 (4)	C5—N5—C10—C9	174.7 (5)
N4i—Sr1—N6—C8	60.8 (5)	C8—N5—C10—C9	−0.6 (7)
N4i—Sr1—N6—C9	−139.2 (4)	Sr1—N6—C8—N5	161.7 (4)
N4ii—Sr1—N6—C8	−119.2 (5)	C9—N6—C8—N5	−0.5 (7)
N4ii—Sr1—N6—C9	40.8 (4)	Sr1—N6—C9—C10	−164.3 (4)
O1iii—Sr1—N6—C8	159.5 (5)	C8—N6—C9—C10	0.1 (7)
O1iii—Sr1—N6—C9	−40.5 (4)	N1—C1—C2—C3	−26.5 (9)
C1—N1—N2—N3	0.3 (6)	N1—C1—C2—C7	156.8 (6)
N2—N1—C1—N4	−0.3 (6)	N4—C1—C2—C3	151.0 (6)
N2—N1—C1—C2	177.6 (5)	N4—C1—C2—C7	−25.6 (8)
N1—N2—N3—N4	−0.1 (6)	C1—C2—C3—C4	−175.4 (6)
N2—N3—N4—C1	−0.1 (6)	C7—C2—C3—C4	1.3 (9)
N2—N3—N4—Sr1iv	−173.6 (4)	C1—C2—C7—C6	174.8 (5)
N3—N4—C1—N1	0.2 (6)	C3—C2—C7—C6	−2.0 (9)
N3—N4—C1—C2	−177.6 (5)	C2—C3—C4—C5	0.5 (9)
Sr1iv—N4—C1—N1	170.0 (4)	C3—C4—C5—N5	177.0 (5)
Sr1iv—N4—C1—C2	−7.8 (10)	C3—C4—C5—C6	−1.7 (9)
C8—N5—C5—C4	−19.4 (9)	N5—C5—C6—C7	−177.7 (5)
C8—N5—C5—C6	159.3 (6)	C4—C5—C6—C7	1.0 (9)
C10—N5—C5—C4	166.4 (6)	C5—C6—C7—C2	0.8 (9)
C10—N5—C5—C6	−14.9 (8)	N6—C9—C10—N5	0.3 (7)
C5—N5—C8—N6	−174.4 (5)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1C···N1v	0.85	2.07	2.915 (7)	171
O1—H1D···N2vi	0.85	2.10	2.948 (6)	171

Symmetry codes: (v) x, y+1, z+1; (vi) −x, −y−1, −z.