Poly[diaqua­(μ3-1H-benzimidazole-5,6-dicarboxyl­ato-κ4N3:O5,O6:O6′)magnesium(II)]

Wang, H.; Li, X.-F.; Song, W.-D.; Ma, X.-T.; Liu, J.-H.

doi:10.1107/S1600536810001029

metal-organic compounds

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Volume 66| Part 2| February 2010| Page m151

https://doi.org/10.1107/S1600536810001029

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Poly[diaqua(μ₃-1H-benzimidazole-5,6-dicarboxylato-κ⁴N³:O⁵,O⁶:O^6′)magnesium(II)]

Hao Wang,^a Xiao-Fei Li,^b Wen-Dong Song,^c ^* Xiao-Tian Ma ^c and Juan-Hua Liu ^c

^aCollege of Food Science and Technology, Guang Dong Ocean University, Zhanjiang 524088, People's Republic of China, ^bCollege of Agriculture, Guang Dong Ocean University, Zhanjiang 524088, People's Republic of China, and ^cCollege of Science, Guang Dong Ocean University, Zhanjiang 524088, People's Republic of China
^*Correspondence e-mail: songwd60@163.com

(Received 28 December 2009; accepted 8 January 2010; online 13 January 2010)

In the title complex, [Mg(C₉H₄N₂O₄)(H₂O)₂]_n, the Mg^II atom is six-coordinated by one N and three O atoms from three different 1H-benzimidazole-5,6-dicarboxylate ligands and two O atoms from two water molecules, forming a slightly distorted octahedral geometry. The ligand links the Mg^II centres into a three-dimensional network. Extensive N—H⋯O and O—H⋯O hydrogen bonds exist between the ligands and water molecules, stabilizing the crystal structure.

Related literature

For related structures of 1H-benzimidazole-5,6-dicarboxylate complexes, see: Song, Wang, Hu et al. (2009 ); Song, Wang, Li et al. (2009 ); Song, Wang, Qin et al. (2009 ); Wang et al. (2009 ).

Experimental

Crystal data

[Mg(C₉H₄N₂O₄)(H₂O)₂]
M_r = 264.48
Monoclinic, C c
a = 7.4793 (15) Å
b = 18.958 (4) Å
c = 7.3132 (15) Å
β = 99.38 (3)°
V = 1023.1 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.20 mm⁻¹
T = 293 K
0.30 × 0.25 × 0.21 mm

Data collection

Rigaku/MSC Mercury CCD diffractometer
Absorption correction: multi-scan (REQAB; Jacobson, 1998 ) T_min = 0.943, T_max = 0.960
4611 measured reflections
1143 independent reflections
1096 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.090
S = 1.06
1143 reflections
163 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.38 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Table 1
Selected bond lengths (Å)

Mg1—N1	2.195 (3)
Mg1—O1ⁱ	2.051 (3)
Mg1—O3ⁱ	2.106 (3)
Mg1—O4ⁱⁱ	2.113 (3)
Mg1—O1W	2.063 (3)
Mg1—O2W	2.074 (3)
Symmetry codes: (i) $[x, -y+1, z-{\script{1\over 2}}]$ ; (ii) $[x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3⋯O1ⁱⁱⁱ	0.86	2.29	2.992 (4)	138
O1W—H1W⋯O2^iv	0.84	1.84	2.651 (4)	163
O1W—H2W⋯O3ⁱⁱ	0.84	1.92	2.734 (4)	164
O2W—H3W⋯O4^iv	0.84	2.27	3.068 (4)	160
O2W—H4W⋯O2^v	0.84	1.87	2.685 (4)	164
Symmetry codes: (ii) $[x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ ; (iii) $[x-1, -y+1, z-{\script{1\over 2}}]$ ; (iv) $[x, -y+1, z+{\script{1\over 2}}]$ ; (v) $[x-{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ .

Data collection: CrystalStructure (Rigaku/MSC, 2002 ); cell refinement: CrystalStructure; data reduction: CrystalStructure; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976 ) and DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810001029/hy2269sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810001029/hy2269Isup2.hkl

checkCIF report

Comment top

1H-Benzimidazole-5,6-dicarboxylic acid (H₂L) can function as a multidentate ligand and several complexes formed from this ligand have been reported recently, including catena-poly[[diaqua(1,10-phenanthroline-κ²N,N') nickel(II)]-µ-L-κ²N³:O⁶] (Song, Wang, Hu et al., 2009), pentaaqua(L-κN³)cobalt(II) pentahydrate (Song, Wang, Li et al., 2009), pentaaqua(L-κN³)nickel(II) pentahydrate (Song, Wang, Qin et al., 2009) and tetraaquabis(L-κN³)cobalt(II) dimethylformamide disolvate dihydrate (Wang et al., 2009). However, the Mg complex of the H₂L ligand has not been reported up to now.

As shown in Fig. 1, the Mg^II atom is six-coordinated by one N and three O atoms from three different L ligands, and two O atoms from two water molecules (Table 1), showing a slightly distorted octahedral geometry. The equatorial plane is defined by O1W, O2W, O1ⁱ and O3ⁱ atoms, while N1 and O4ⁱⁱ occupy the axial positions [symmetry codes: (i) x, 1 - y, -1/2 + z; (ii) 1/2 + x, 1/2 + y, z]. Intermolecular O—H···O and N—H···O hydrogen bonds between the ligand and the coordinated water molecules stabilize the structure (Table 2 and Fig 2).

Related literature top

For related structures of 1H-benzimidazole-5,6-dicarboxylate complexes, see: Song, Wang, Hu et al. (2009); Song, Wang, Li et al. (2009); Song, Wang, Qin et al. (2009); Wang et al. (2009).

Experimental top

A mixture of MgCl₂ (1.0 mmol), H₂L (0.6 mmol), CH₃CN (6 ml) and water (4 ml) was added to a 20 ml Teflon-lined stainless container, which was heated to 150°C and held at that temperature for 5 d. After cooling to room temperature, colourless crystals were recovered by filtration.

Structure description top

For related structures of 1H-benzimidazole-5,6-dicarboxylate complexes, see: Song, Wang, Hu et al. (2009); Song, Wang, Li et al. (2009); Song, Wang, Qin et al. (2009); Wang et al. (2009).

Computing details top

Data collection: CrystalStructure (Rigaku/MSC, 2002); cell refinement: CrystalStructure (Rigaku/MSC, 2002); data reduction: CrystalStructure (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The structure of the title compound, showing the 30% probability displacement ellipsoids. [Symmetry codes: (i) x, 1 - y, -1/2 + z; (ii) 1/2 + x, 1/2 + y, z.]
	Fig. 2. A view of the three-dimensional network structure of the title compound. Hydrogen bonds are shown as dashed lines.

Poly[diaqua(µ₃-1H-benzimidazole-5,6-dicarboxylato- κ⁴N³:O⁵,O⁶:O^6')magnesium(II)] top

Crystal data top

[Mg(C₉H₄N₂O₄)(H₂O)₂]	F(000) = 544
M_r = 264.48	D_x = 1.717 Mg m⁻³
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 4114 reflections
a = 7.4793 (15) Å	θ = 3.6–27.5°
b = 18.958 (4) Å	µ = 0.20 mm⁻¹
c = 7.3132 (15) Å	T = 293 K
β = 99.38 (3)°	Block, colourless
V = 1023.1 (4) Å³	0.30 × 0.25 × 0.21 mm
Z = 4

Data collection top

Rigaku/MSC Mercury CCD diffractometer	1143 independent reflections
Radiation source: fine-focus sealed tube	1096 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
ω scans	θ_max = 27.5°, θ_min = 3.6°
Absorption correction: multi-scan (REQAB; Jacobson, 1998)	h = −9→9
T_min = 0.943, T_max = 0.960	k = −24→24
4611 measured reflections	l = −8→9

Refinement top

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)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.090	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.04P)² + 2P] where P = (F_o² + 2F_c²)/3
1143 reflections	(Δ/σ)_max < 0.001
163 parameters	Δρ_max = 0.38 e Å⁻³
2 restraints	Δρ_min = −0.25 e Å⁻³

Crystal data top

[Mg(C₉H₄N₂O₄)(H₂O)₂]	V = 1023.1 (4) Å³
M_r = 264.48	Z = 4
Monoclinic, Cc	Mo Kα radiation
a = 7.4793 (15) Å	µ = 0.20 mm⁻¹
b = 18.958 (4) Å	T = 293 K
c = 7.3132 (15) Å	0.30 × 0.25 × 0.21 mm
β = 99.38 (3)°

Data collection top

Rigaku/MSC Mercury CCD diffractometer	1143 independent reflections
Absorption correction: multi-scan (REQAB; Jacobson, 1998)	1096 reflections with I > 2σ(I)
T_min = 0.943, T_max = 0.960	R_int = 0.031
4611 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	2 restraints
wR(F²) = 0.090	H-atom parameters constrained
S = 1.06	Δρ_max = 0.38 e Å⁻³
1143 reflections	Δρ_min = −0.25 e Å⁻³
163 parameters

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

	x	y	z	U_iso*/U_eq
Mg1	0.27807 (16)	0.68928 (5)	0.63241 (16)	0.0172 (3)
O1	0.4349 (4)	0.37147 (14)	0.9888 (4)	0.0234 (5)
O2	0.5047 (4)	0.37926 (16)	0.7087 (4)	0.0317 (7)
O3	0.1320 (4)	0.28489 (12)	0.8699 (4)	0.0237 (6)
O4	−0.0733 (4)	0.28304 (12)	0.6132 (3)	0.0236 (6)
N1	0.0678 (5)	0.61142 (15)	0.6633 (5)	0.0214 (6)
N3	−0.2035 (5)	0.56134 (16)	0.6122 (5)	0.0271 (7)
H3	−0.3196	0.5577	0.5874	0.033*
C1	0.0380 (5)	0.31481 (16)	0.7326 (5)	0.0173 (6)
C2	0.0549 (5)	0.39389 (16)	0.7123 (5)	0.0182 (7)
C3	−0.1002 (5)	0.43318 (18)	0.6560 (5)	0.0223 (7)
H2	−0.2127	0.4116	0.6240	0.027*
C4	−0.0816 (5)	0.50629 (18)	0.6490 (5)	0.0206 (7)
C5	0.0876 (5)	0.53907 (17)	0.6828 (5)	0.0184 (7)
C6	0.2438 (5)	0.49930 (18)	0.7332 (5)	0.0185 (7)
H1	0.3574	0.5206	0.7531	0.022*
C7	0.2259 (4)	0.42738 (16)	0.7529 (4)	0.0154 (6)
C8	0.3985 (5)	0.38839 (17)	0.8204 (5)	0.0173 (7)
C9	−0.1073 (6)	0.62155 (18)	0.6224 (6)	0.0262 (8)
H9	−0.1599	0.6659	0.6023	0.031*
O1W	0.4663 (4)	0.65596 (14)	0.8537 (4)	0.0289 (6)
H1W	0.4573	0.6408	0.9598	0.043*
H2W	0.5355	0.6911	0.8601	0.043*
O2W	0.1388 (5)	0.75021 (15)	0.7982 (5)	0.0374 (8)
H3W	0.0660	0.7342	0.8639	0.056*
H4W	0.1176	0.7927	0.7704	0.056*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mg1	0.0191 (6)	0.0134 (4)	0.0184 (5)	−0.0004 (4)	0.0009 (4)	0.0004 (4)
O1	0.0186 (13)	0.0310 (13)	0.0202 (12)	0.0004 (10)	0.0019 (11)	0.0074 (10)
O2	0.0247 (16)	0.0462 (17)	0.0253 (14)	0.0133 (12)	0.0075 (12)	0.0005 (12)
O3	0.0274 (14)	0.0165 (11)	0.0235 (12)	−0.0008 (10)	−0.0074 (11)	0.0006 (9)
O4	0.0281 (15)	0.0195 (12)	0.0203 (13)	−0.0067 (10)	−0.0045 (11)	0.0014 (9)
N1	0.0215 (16)	0.0167 (13)	0.0265 (15)	0.0018 (11)	0.0058 (12)	0.0039 (11)
N3	0.0147 (16)	0.0249 (14)	0.0400 (19)	0.0032 (12)	−0.0009 (14)	0.0065 (13)
C1	0.0195 (17)	0.0151 (13)	0.0175 (16)	−0.0016 (12)	0.0043 (14)	−0.0002 (11)
C2	0.0197 (18)	0.0150 (14)	0.0192 (16)	−0.0024 (12)	0.0008 (14)	0.0015 (12)
C3	0.0184 (18)	0.0204 (16)	0.0274 (19)	−0.0040 (13)	0.0011 (15)	0.0023 (13)
C4	0.0151 (19)	0.0216 (16)	0.0244 (18)	0.0023 (12)	0.0011 (14)	0.0045 (13)
C5	0.0191 (17)	0.0160 (14)	0.0203 (16)	−0.0019 (12)	0.0035 (14)	0.0016 (12)
C6	0.0129 (16)	0.0198 (15)	0.0224 (17)	−0.0022 (11)	0.0018 (14)	0.0008 (12)
C7	0.0151 (16)	0.0178 (14)	0.0134 (14)	0.0002 (12)	0.0027 (13)	−0.0002 (11)
C8	0.0154 (17)	0.0154 (14)	0.0204 (17)	−0.0024 (11)	0.0007 (14)	−0.0011 (11)
C9	0.024 (2)	0.0208 (16)	0.034 (2)	0.0068 (14)	0.0050 (17)	0.0067 (14)
O1W	0.0340 (15)	0.0271 (13)	0.0225 (12)	−0.0071 (11)	−0.0043 (12)	0.0052 (10)
O2W	0.0486 (19)	0.0219 (12)	0.0476 (19)	0.0063 (12)	0.0251 (16)	−0.0022 (12)

Geometric parameters (Å, º) top

Mg1—N1	2.195 (3)	C1—C2	1.514 (4)
Mg1—O1ⁱ	2.051 (3)	C2—C3	1.384 (5)
Mg1—O3ⁱ	2.106 (3)	C2—C7	1.416 (5)
Mg1—O4ⁱⁱ	2.113 (3)	C3—C4	1.395 (5)
Mg1—O1W	2.063 (3)	C3—H2	0.9300
Mg1—O2W	2.074 (3)	C4—C5	1.395 (5)
O1—C8	1.259 (4)	C5—C6	1.388 (5)
O2—C8	1.241 (4)	C6—C7	1.380 (5)
O3—C1	1.263 (4)	C6—H1	0.9300
O4—C1	1.257 (4)	C7—C8	1.499 (5)
N1—C9	1.310 (5)	C9—H9	0.9300
N1—C5	1.384 (4)	O1W—H1W	0.8401
N3—C9	1.345 (5)	O1W—H2W	0.8400
N3—C4	1.383 (5)	O2W—H3W	0.8399
N3—H3	0.8600	O2W—H4W	0.8400

O1ⁱ—Mg1—O1W	81.69 (12)	C7—C2—C1	120.7 (3)
O1ⁱ—Mg1—O2W	174.71 (15)	C2—C3—C4	117.5 (3)
O1W—Mg1—O2W	93.18 (14)	C2—C3—H2	121.2
O1ⁱ—Mg1—O3ⁱ	85.34 (12)	C4—C3—H2	121.3
O1W—Mg1—O3ⁱ	166.51 (13)	N3—C4—C3	133.6 (3)
O2W—Mg1—O3ⁱ	99.68 (13)	N3—C4—C5	104.4 (3)
O1ⁱ—Mg1—O4ⁱⁱ	95.02 (12)	C3—C4—C5	122.0 (3)
O1W—Mg1—O4ⁱⁱ	90.61 (11)	N1—C5—C6	129.5 (3)
O2W—Mg1—O4ⁱⁱ	83.68 (12)	N1—C5—C4	110.1 (3)
O3ⁱ—Mg1—O4ⁱⁱ	86.80 (11)	C6—C5—C4	120.3 (3)
O1ⁱ—Mg1—N1	98.87 (12)	C7—C6—C5	118.2 (3)
O1W—Mg1—N1	97.00 (12)	C7—C6—H1	120.9
O2W—Mg1—N1	82.98 (13)	C5—C6—H1	120.9
O3ⁱ—Mg1—N1	88.65 (12)	C6—C7—C2	121.4 (3)
O4ⁱⁱ—Mg1—N1	164.98 (12)	C6—C7—C8	115.4 (3)
C8—O1—Mg1ⁱⁱⁱ	126.4 (2)	C2—C7—C8	123.2 (3)
C1—O3—Mg1ⁱⁱⁱ	139.4 (2)	O2—C8—O1	123.3 (3)
C1—O4—Mg1^iv	130.8 (2)	O2—C8—C7	117.5 (3)
C9—N1—C5	104.8 (3)	O1—C8—C7	119.0 (3)
C9—N1—Mg1	125.8 (2)	N1—C9—N3	113.2 (3)
C5—N1—Mg1	127.6 (3)	N1—C9—H9	123.4
C9—N3—C4	107.4 (3)	N3—C9—H9	123.4
C9—N3—H3	126.3	Mg1—O1W—H1W	133.0
C4—N3—H3	126.3	Mg1—O1W—H2W	97.9
O4—C1—O3	123.8 (3)	H1W—O1W—H2W	111.1
O4—C1—C2	117.6 (3)	Mg1—O2W—H3W	124.6
O3—C1—C2	118.6 (3)	Mg1—O2W—H4W	119.1
C3—C2—C7	120.4 (3)	H3W—O2W—H4W	111.8
C3—C2—C1	118.9 (3)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···O1^v	0.86	2.29	2.992 (4)	138
O1W—H1W···O2ⁱⁱⁱ	0.84	1.84	2.651 (4)	163
O1W—H2W···O3ⁱⁱ	0.84	1.92	2.734 (4)	164
O2W—H3W···O4ⁱⁱⁱ	0.84	2.27	3.068 (4)	160
O2W—H4W···O2^vi	0.84	1.87	2.685 (4)	164

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

Experimental details

Crystal data
Chemical formula	[Mg(C₉H₄N₂O₄)(H₂O)₂]
M_r	264.48
Crystal system, space group	Monoclinic, Cc
Temperature (K)	293
a, b, c (Å)	7.4793 (15), 18.958 (4), 7.3132 (15)
β (°)	99.38 (3)
V (Å³)	1023.1 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.20
Crystal size (mm)	0.30 × 0.25 × 0.21

Data collection
Diffractometer	Rigaku/MSC Mercury CCD
Absorption correction	Multi-scan (REQAB; Jacobson, 1998)
T_min, T_max	0.943, 0.960
No. of measured, independent and observed [I > 2σ(I)] reflections	4611, 1143, 1096
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.090, 1.06
No. of reflections	1143
No. of parameters	163
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.38, −0.25

Computer programs: CrystalStructure (Rigaku/MSC, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPII (Johnson, 1976) and DIAMOND (Brandenburg, 1999).

Selected bond lengths (Å) top

Mg1—N1	2.195 (3)	Mg1—O4ⁱⁱ	2.113 (3)
Mg1—O1ⁱ	2.051 (3)	Mg1—O1W	2.063 (3)
Mg1—O3ⁱ	2.106 (3)	Mg1—O2W	2.074 (3)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···O1ⁱⁱⁱ	0.86	2.29	2.992 (4)	138.4
O1W—H1W···O2^iv	0.84	1.84	2.651 (4)	162.7
O1W—H2W···O3ⁱⁱ	0.84	1.92	2.734 (4)	164.2
O2W—H3W···O4^iv	0.84	2.27	3.068 (4)	159.9
O2W—H4W···O2^v	0.84	1.87	2.685 (4)	164.2

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

Acknowledgements

The authors acknowledge Guang Dong Ocean University for supporting this work.

References

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