catena-Poly[[diaqua­strontium]-bis­(μ-2-bromo­benzoato)-κ2O,O′:O′;κ3O:O,O′]

Zhang, B.-S.

doi:10.1107/S1600536809045395

metal-organic compounds

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Volume 65| Part 12| December 2009| Page m1500

doi:10.1107/S1600536809045395

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catena-Poly[[diaquastrontium]-bis(μ-2-bromobenzoato)-κ²O,O′:O′;κ³O:O,O′]

Bi-Song Zhang ^a ^*

^aCollege of Material Science and Chemical Engineering, Jinhua College of Profession and Technology, Jinhua, Zhejiang 321017, People's Republic of China
^*Correspondence e-mail: zbs_jy@163.com

(Received 9 October 2009; accepted 29 October 2009; online 4 November 2009)

The hydrothermal reaction of SrCO₃ and 2-bromobenzoic acid in CH₃OH–H₂O afforded the Sr^II title polymeric complex, [Sr(C₇H₄BrO₂)₂(H₂O)₂]_n. Within the coordination sphere, the Sr^II ion is located on a crystallographic twofold axis, and is coordinated by eight O atoms from two water molecules and four carboxylate groups of 2-bromobenzoate ligands in an irregular coordination geometry. Two μ₃-carboxylate groups of the 2-bromobenzoate anions bridge two symmetry-related Sr^II atoms, giving rise to a chain structure extending along [001]. The polymeric chains are connected via O—H⋯O and O—H⋯Br hydrogen bonds interactions into a three-dimensional supramolecular network.

Related literature

For other metal complexes with the 2-bromobenzoato ligand, see: Zhang et al. (2005 , 2008 ); Zhang (2006 ); Wang et al. (2003 ). For related structures, see: Zhang (2008 ); Karipides et al. (1988 ).

Experimental

Crystal data

[Sr(C₇H₄BrO₂)₂(H₂O)₂]
M_r = 523.68
Orthorhombic, P b c n
a = 18.740 (4) Å
b = 11.669 (2) Å
c = 8.0529 (16) Å
V = 1760.9 (6) Å³
Z = 4
Mo Kα radiation
μ = 7.62 mm⁻¹
T = 290 K
0.36 × 0.20 × 0.16 mm

Data collection

Rigaku R-AXIS RAPID diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.170, T_max = 0.309
12747 measured reflections
1550 independent reflections
1273 reflections with I > 2σ(I)
R_int = 0.090

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.130
S = 1.14
1550 reflections
106 parameters
H-atom parameters constrained
Δρ_max = 0.84 e Å⁻³
Δρ_min = −0.78 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯O2ⁱ	0.82	1.98	2.753 (5)	156
O1—H1B⋯Br1ⁱⁱ	0.82	2.81	3.603 (2)	164
Symmetry codes: (i) -x+1, -y+2, -z; (ii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ .

Data collection: RAPID-AUTO (Rigaku, 1998 ); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku, 1998); 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.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809045395/bh2255sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809045395/bh2255Isup2.hkl

checkCIF report

Comment top

Metal ions with 2-bromobenzoato ligands can form, among others, mononuclear, dinuclear complexes (Zhang et al., 2005, 2008; Zhang, 2006; Wang et al., 2003) but very few reports on one-dimensional chain structures complexes including 2-bromobenzoato ligands have been published.

In this paper, we would like to report the synthesis and crystal structure of a one-dimensional chain complex including 2-bromobenzoato and Strontium(II). The crystal structure of the title compound is similar to previously published structures (Zhang, 2008; Karipides et al., 1988). Within the title compound, each Sr^II ion is located on a crystallographic two-fold axis and is coordinated by eight O atoms from two water molecules and four carboxyl groups of 2-bromobenzoic acid anions in an irregular coordination geometry. Two µ₃-carboxyl groups of the 2-bromobenzoic anions bridge two symmetry related Strontium atoms, giving rise to a one-dimensional chain structure extending along the [001] direction, with Sr—O bond lengths in the range of 2.498 (3) to 2.753 (4) Å. Separation between Sr and Sr^iv (symmetry code iv: -x+1, -y+2, -z+1) is 4.1703 (8) Å (Fig. 1). The polymeric chains are connected via O—H···O and O—H···Br hydrogen bonds interactions in a three-dimensional supramolecular structure (Fig. 2). The O1—H1A···O3 and O1—H1A···Br1 separations are 2.753 Å and 3.603 Å. The O—H···O and O1—H1A···Br1 bond angles are 156 ° and 164°, Table 2.

Related literature top

For other metal complexes with the 2-bromobenzoato ligand, see: Zhang et al. (2005, 2008); Zhang (2006); Wang et al. (2003). For related structures, see: Zhang (2008); Karipides et al. (1988).

Experimental top

SrCl₂.6H₂O. (0.533 g, 2.00 mmol) was dissolved in the appropriate amount of water, and then 1M Na₂CO₃ solution was added. SrCO₃ was obtained by filtration, which was then washed with distilled water (5 times). The freshly prepared SrCO₃, 2-bromobenzoic acid (0.402 g, 2.00 mmol), CH₃OH/H₂O (v/v = 1:2, 15 ml) were mixed and stirred for 2.0 h. Subsequently, the resulting cream suspension was heated in a 23 ml Teflon-lined stainless steel autoclave at 433 K for 5800 minutes. After the autoclave was cooled to room temperature according to the procedure at 2600 minutes, the solid was filtered off. The resulting filtrate was allowed to stand at room temperature, and slow evaporation for 6 weeks afforded colorless block-shaped single crystals.

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku, 1998); 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 top

	Fig. 1. The one-dimensional chain structure of the title compound, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A packing diagram of the title complex, viewed along the c axis, The O—H···O and O—H···Br hydrogen bonds (dashed lines) in the title compound.

catena-Poly[[diaquastrontium]-bis(µ-2-bromobenzoato)-κ²O,O':O';κ³O:O,O'] top

Crystal data top

[Sr(C₇H₄BrO₂)₂(H₂O)₂]	F(000) = 1008
M_r = 523.68	D_x = 1.975 Mg m⁻³
Orthorhombic, Pbcn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2ab	Cell parameters from 9800 reflections
a = 18.740 (4) Å	θ = 3.3–25.0°
b = 11.669 (2) Å	µ = 7.62 mm⁻¹
c = 8.0529 (16) Å	T = 290 K
V = 1760.9 (6) Å³	Block, colorless
Z = 4	0.36 × 0.20 × 0.16 mm

Data collection top

Rigaku R-AXIS RAPID diffractometer	1550 independent reflections
Radiation source: fine-focus sealed tube	1273 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.090
ω scans	θ_max = 25.0°, θ_min = 3.3°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −22→22
T_min = 0.170, T_max = 0.309	k = −13→13
12747 measured reflections	l = −9→8

Refinement top

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)] = 0.042	H-atom parameters constrained
wR(F²) = 0.130	w = 1/[σ²(F_o²) + (0.0652P)² + 1.8313P] where P = (F_o² + 2F_c²)/3
S = 1.14	(Δ/σ)_max < 0.001
1550 reflections	Δρ_max = 0.84 e Å⁻³
106 parameters	Δρ_min = −0.78 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 constraints	Extinction coefficient: 0.0016 (6)
Primary atom site location: structure-invariant direct methods

Crystal data top

[Sr(C₇H₄BrO₂)₂(H₂O)₂]	V = 1760.9 (6) Å³
M_r = 523.68	Z = 4
Orthorhombic, Pbcn	Mo Kα radiation
a = 18.740 (4) Å	µ = 7.62 mm⁻¹
b = 11.669 (2) Å	T = 290 K
c = 8.0529 (16) Å	0.36 × 0.20 × 0.16 mm

Data collection top

Rigaku R-AXIS RAPID diffractometer	1550 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	1273 reflections with I > 2σ(I)
T_min = 0.170, T_max = 0.309	R_int = 0.090
12747 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.130	H-atom parameters constrained
S = 1.14	Δρ_max = 0.84 e Å⁻³
1550 reflections	Δρ_min = −0.78 e Å⁻³
106 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Sr1	0.5000	0.95347 (6)	0.2500	0.0294 (3)
Br1	0.26073 (4)	1.23028 (6)	0.28032 (9)	0.0528 (3)
O1	0.4082 (2)	0.8205 (4)	0.1116 (5)	0.0577 (12)
H1A	0.4050	0.8178	0.0101	0.087*
H1B	0.3663	0.8112	0.1371	0.087*
O2	0.5875 (3)	1.1245 (4)	0.2207 (4)	0.0523 (13)
O3	0.4433 (2)	1.1017 (3)	0.0190 (4)	0.0395 (10)
C1	0.4152 (3)	1.1591 (4)	0.1317 (6)	0.0335 (12)
C2	0.3870 (3)	1.2758 (4)	0.0915 (6)	0.0318 (12)
C3	0.3238 (3)	1.3201 (4)	0.1490 (6)	0.0404 (14)
C4	0.3005 (4)	1.4307 (5)	0.1105 (8)	0.0475 (16)
H4	0.2569	1.4575	0.1495	0.057*
C5	0.3434 (5)	1.4993 (5)	0.0138 (8)	0.0549 (19)
H5A	0.3293	1.5739	−0.0105	0.066*
C6	0.4068 (5)	1.4582 (5)	−0.0469 (8)	0.060 (2)
H6	0.4352	1.5050	−0.1129	0.072*
C7	0.4288 (3)	1.3487 (5)	−0.0113 (7)	0.0452 (15)
H7	0.4716	1.3218	−0.0549	0.054*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Sr1	0.0387 (5)	0.0285 (4)	0.0210 (4)	0.000	0.0023 (3)	0.000
Br1	0.0460 (5)	0.0583 (5)	0.0542 (5)	0.0021 (3)	0.0062 (3)	0.0062 (3)
O1	0.058 (3)	0.077 (3)	0.038 (2)	−0.029 (2)	−0.002 (2)	0.003 (2)
O2	0.076 (4)	0.053 (3)	0.028 (2)	−0.026 (2)	0.007 (2)	−0.0068 (18)
O3	0.052 (3)	0.041 (2)	0.0251 (19)	0.0051 (18)	0.0075 (17)	−0.0051 (16)
C1	0.034 (3)	0.039 (3)	0.028 (3)	0.007 (2)	0.000 (2)	−0.001 (2)
C2	0.037 (3)	0.031 (3)	0.027 (3)	0.008 (2)	−0.003 (2)	−0.006 (2)
C3	0.060 (4)	0.035 (3)	0.026 (3)	0.008 (3)	−0.010 (3)	0.000 (2)
C4	0.053 (4)	0.043 (3)	0.047 (4)	0.011 (3)	−0.009 (3)	−0.006 (3)
C5	0.080 (6)	0.034 (3)	0.052 (4)	0.010 (3)	−0.011 (4)	0.001 (3)
C6	0.087 (6)	0.046 (4)	0.047 (4)	−0.014 (4)	−0.006 (4)	0.012 (3)
C7	0.047 (4)	0.044 (3)	0.045 (3)	−0.005 (3)	0.004 (3)	0.000 (3)

Geometric parameters (Å, º) top

Sr1—O3ⁱ	2.498 (3)	O3—C1	1.244 (6)
Sr1—O3ⁱⁱ	2.498 (3)	O3—Sr1ⁱ	2.498 (3)
Sr1—O1	2.570 (4)	C1—O2ⁱⁱⁱ	1.257 (6)
Sr1—O1ⁱⁱⁱ	2.570 (4)	C1—C2	1.496 (7)
Sr1—O2	2.594 (4)	C2—C3	1.373 (8)
Sr1—O2ⁱⁱⁱ	2.594 (4)	C2—C7	1.422 (8)
Sr1—O3ⁱⁱⁱ	2.753 (4)	C3—C4	1.397 (8)
Sr1—O3	2.753 (4)	C4—C5	1.376 (10)
Sr1—C1ⁱⁱⁱ	3.031 (5)	C4—H4	0.9300
Sr1—C1	3.031 (5)	C5—C6	1.371 (11)
Br1—C3	1.901 (6)	C5—H5A	0.9300
O1—H1A	0.8200	C6—C7	1.373 (9)
O1—H1B	0.8200	C6—H6	0.9300
O2—C1ⁱⁱⁱ	1.257 (6)	C7—H7	0.9300

O3ⁱ—Sr1—O3ⁱⁱ	150.14 (16)	O2—Sr1—Sr1^iv	83.55 (8)
O3ⁱ—Sr1—O1	75.71 (13)	O2ⁱⁱⁱ—Sr1—Sr1^iv	73.25 (8)
O3ⁱⁱ—Sr1—O1	86.32 (12)	O3ⁱⁱⁱ—Sr1—Sr1^iv	35.34 (7)
O3ⁱ—Sr1—O1ⁱⁱⁱ	86.32 (12)	O3—Sr1—Sr1^iv	119.25 (7)
O3ⁱⁱ—Sr1—O1ⁱⁱⁱ	75.71 (13)	C1ⁱⁱⁱ—Sr1—Sr1^iv	59.36 (10)
O1—Sr1—O1ⁱⁱⁱ	105.7 (2)	C1—Sr1—Sr1^iv	95.59 (10)
O3ⁱ—Sr1—O2	81.37 (12)	O3ⁱ—Sr1—Sr1ⁱ	39.61 (8)
O3ⁱⁱ—Sr1—O2	123.12 (11)	O3ⁱⁱ—Sr1—Sr1ⁱ	154.76 (9)
O1—Sr1—O2	147.99 (12)	O1—Sr1—Sr1ⁱ	74.84 (9)
O1ⁱⁱⁱ—Sr1—O2	94.65 (16)	O1ⁱⁱⁱ—Sr1—Sr1ⁱ	125.16 (9)
O3ⁱ—Sr1—O2ⁱⁱⁱ	123.12 (11)	O2—Sr1—Sr1ⁱ	73.25 (8)
O3ⁱⁱ—Sr1—O2ⁱⁱⁱ	81.37 (12)	O2ⁱⁱⁱ—Sr1—Sr1ⁱ	83.55 (8)
O1—Sr1—O2ⁱⁱⁱ	94.65 (16)	O3ⁱⁱⁱ—Sr1—Sr1ⁱ	119.25 (7)
O1ⁱⁱⁱ—Sr1—O2ⁱⁱⁱ	147.99 (12)	O3—Sr1—Sr1ⁱ	35.34 (7)
O2—Sr1—O2ⁱⁱⁱ	79.4 (2)	C1ⁱⁱⁱ—Sr1—Sr1ⁱ	95.59 (10)
O3ⁱ—Sr1—O3ⁱⁱⁱ	125.68 (15)	C1—Sr1—Sr1ⁱ	59.36 (9)
O3ⁱⁱ—Sr1—O3ⁱⁱⁱ	74.95 (13)	Sr1^iv—Sr1—Sr1ⁱ	149.82 (4)
O1—Sr1—O3ⁱⁱⁱ	158.51 (13)	Sr1—O1—H1A	120.4
O1ⁱⁱⁱ—Sr1—O3ⁱⁱⁱ	80.09 (12)	Sr1—O1—H1B	127.8
O2—Sr1—O3ⁱⁱⁱ	48.25 (10)	H1A—O1—H1B	99.9
O2ⁱⁱⁱ—Sr1—O3ⁱⁱⁱ	72.51 (13)	C1ⁱⁱⁱ—O2—Sr1	97.8 (3)
O3ⁱ—Sr1—O3	74.95 (13)	C1—O3—Sr1ⁱ	162.0 (3)
O3ⁱⁱ—Sr1—O3	125.68 (15)	C1—O3—Sr1	90.5 (3)
O1—Sr1—O3	80.09 (12)	Sr1ⁱ—O3—Sr1	105.05 (13)
O1ⁱⁱⁱ—Sr1—O3	158.51 (13)	O3—C1—O2ⁱⁱⁱ	122.3 (5)
O2—Sr1—O3	72.51 (13)	O3—C1—C2	118.8 (4)
O2ⁱⁱⁱ—Sr1—O3	48.25 (10)	O2ⁱⁱⁱ—C1—C2	118.9 (4)
O3ⁱⁱⁱ—Sr1—O3	102.18 (15)	O3—C1—Sr1	65.3 (3)
O3ⁱ—Sr1—C1ⁱⁱⁱ	104.69 (13)	O2ⁱⁱⁱ—C1—Sr1	58.0 (3)
O3ⁱⁱ—Sr1—C1ⁱⁱⁱ	98.88 (13)	C2—C1—Sr1	166.8 (4)
O1—Sr1—C1ⁱⁱⁱ	164.74 (14)	C3—C2—C7	116.5 (5)
O1ⁱⁱⁱ—Sr1—C1ⁱⁱⁱ	89.49 (15)	C3—C2—C1	125.1 (5)
O2—Sr1—C1ⁱⁱⁱ	24.26 (12)	C7—C2—C1	118.4 (5)
O2ⁱⁱⁱ—Sr1—C1ⁱⁱⁱ	72.16 (16)	C2—C3—C4	122.8 (6)
O3ⁱⁱⁱ—Sr1—C1ⁱⁱⁱ	24.23 (11)	C2—C3—Br1	121.1 (4)
O3—Sr1—C1ⁱⁱⁱ	85.27 (13)	C4—C3—Br1	116.0 (5)
O3ⁱ—Sr1—C1	98.88 (13)	C5—C4—C3	118.7 (6)
O3ⁱⁱ—Sr1—C1	104.69 (13)	C5—C4—H4	120.6
O1—Sr1—C1	89.49 (15)	C3—C4—H4	120.6
O1ⁱⁱⁱ—Sr1—C1	164.74 (14)	C6—C5—C4	120.2 (6)
O2—Sr1—C1	72.16 (16)	C6—C5—H5A	119.9
O2ⁱⁱⁱ—Sr1—C1	24.26 (12)	C4—C5—H5A	119.9
O3ⁱⁱⁱ—Sr1—C1	85.27 (13)	C5—C6—C7	120.8 (7)
O3—Sr1—C1	24.23 (11)	C5—C6—H6	119.6
C1ⁱⁱⁱ—Sr1—C1	75.3 (2)	C7—C6—H6	119.6
O3ⁱ—Sr1—Sr1^iv	154.76 (9)	C6—C7—C2	120.8 (6)
O3ⁱⁱ—Sr1—Sr1^iv	39.61 (8)	C6—C7—H7	119.6
O1—Sr1—Sr1^iv	125.16 (9)	C2—C7—H7	119.6
O1ⁱⁱⁱ—Sr1—Sr1^iv	74.84 (9)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O2ⁱ	0.82	1.98	2.753 (5)	156
O1—H1B···Br1^v	0.82	2.81	3.603 (2)	164

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

Experimental details

Crystal data
Chemical formula	[Sr(C₇H₄BrO₂)₂(H₂O)₂]
M_r	523.68
Crystal system, space group	Orthorhombic, Pbcn
Temperature (K)	290
a, b, c (Å)	18.740 (4), 11.669 (2), 8.0529 (16)
V (Å³)	1760.9 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	7.62
Crystal size (mm)	0.36 × 0.20 × 0.16

Data collection
Diffractometer	Rigaku R-AXIS RAPID diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.170, 0.309
No. of measured, independent and observed [I > 2σ(I)] reflections	12747, 1550, 1273
R_int	0.090
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.130, 1.14
No. of reflections	1550
No. of parameters	106
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.84, −0.78

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O2ⁱ	0.820	1.982	2.753 (5)	156
O1—H1B···Br1ⁱⁱ	0.820	2.808	3.603 (2)	164

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

Acknowledgements

The author gratefully acknowledges the financial support of the Education office of Zhejiang Province (grant No. 20051316).

References

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