Poly[(μ-1H-benzimidazole-5,6-dicarboxyl­ato)lead(II)]

Chen, J.; Zheng, C.; Wang, Y.; Yun, T.; Luo, Y.

doi:10.1107/S1600536811017065

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page m755

doi:10.1107/S1600536811017065

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Poly[(μ-1H-benzimidazole-5,6-dicarboxylato)lead(II)]

Jinhua Chen,^a Chun Zheng,^a Yuezhu Wang,^a Tingting Yun ^a and Yifan Luo ^a ^*

^aSchool of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China
^*Correspondence e-mail: luoyf2010@yahoo.com.cn

(Received 2 April 2011; accepted 5 May 2011; online 14 May 2011)

The crystal structure of the two-dimensional polymeric title compound, [Pb(C₉H₄N₂O₄)]_n, comprises one crystallographically independent Pb^II atom and one fully deprotonated 1H-benzimidazole-5,6-dicarboxylate (H₂L) ligand. The Pb^II atom is seven-coordinated by six O atoms and one N atom from the H₂L ligands, giving a capped octahedral coordination geometry. The structure is a layered two-dimensional coordination polymer extending parallel to (100) with N—H⋯O hydrogen bonds interactions between the layers, stabilizing the crystal structure.

Related literature

For applications of metal-organic frameworks, see: Li et al. (2007 ). For related structures, see: Gao et al. (2008 ); Lo et al.. (2007 ); Wang et al. (2009 ); Wei et al. (2008 );Yao et al. (2008 ); Zhai (2009 ).

Experimental

Crystal data

[Pb(C₉H₄N₂O₄)]
M_r = 411.34
Monoclinic, P 2₁ /c
a = 13.127 (2) Å
b = 9.5571 (14) Å
c = 6.7557 (10) Å
β = 99.587 (2)°
V = 835.7 (2) Å³
Z = 4
Mo Kα radiation
μ = 20.19 mm⁻¹
T = 273 K
0.30 × 0.30 × 0.27 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.003, T_max = 0.004
3954 measured reflections
1458 independent reflections
1273 reflections with I > 2σ(I)
R_int = 0.042

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.120
S = 1.08
1458 reflections
133 parameters
12 restraints
H-atom parameters constrained
Δρ_max = 3.24 e Å⁻³
Δρ_min = −2.83 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2⋯O4ⁱ	0.86	2.02	2.723 (12)	138
Symmetry code: (i) $[-x+2, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811017065/go2009sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811017065/go2009Isup2.hkl

checkCIF report

Comment top

In recent years, metal-organic frameworks (MOF) based on supramolecular chemistry and crystal engineering have attracted extensive attention not only due to their diverse topologies and intriguing structures but also owing to their interesting physical and chemical properties, such as photoluminescence, magnetism, ferroelectricity, gas storage, ion exchange and catalysis, Li et al. (2007). N-Heterocyclic multicarboxylic acids have been widely used to construct MOF for their potential application. 1H-benzimidazole-5,6-dicarboxylic acid possesses two nitrogen atoms of imidazole ring and four oxygen atoms of carboxylate groups, and might be used as versatile linker in constructing coordination polymers with abundant hydrogen bonds. Several coordination polymers fomed by this ligand have been reported recently: Gao et al. (2008); Lo et al. (2007); Wang et al. (2009); Wei et al. (2008); Yao et al. (2008); Zhai (2009). Herein we report the synthesis and crystal structure of the title complex of (C₉H₄N₂O₄Pb)_n, Fig. 1. This is a layered 2D-coordination polymer structure with H-bonds interactions between the layers which is shown in Fig. 2.

Related literature top

For applications of metal-organic frameworks, see: Li et al. (2007). For related structures, see: Gao et al. (2008); Lo et al.. (2007); Wang et al. (2009); Wei et al. (2008);Yao et al. (2008); Zhai (2009).

Experimental top

A mixture of Pb(CH₃COO)₂ (0.6 mmol), H₂L(0.6 mmol) and water (13 ml) was added to a 25 ml teflon-lined stainless container, which was heated to 430K and held at that temperature for 3 days. After cooling to room temperature, yellow crystals were recovered by filtration.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The structure of the title compound, showing the atomic numbering scheme. Non-H atoms are shown with 30% probability displacement ellipsoids.
	Fig. 2. The packing diagram of the title compound, with H atoms omitted for clarity. Hydrogen bonds are shown as dashed lines.

Poly[(µ-1H-benzimidazole-5,6-dicarboxylato)lead(II)] top

Crystal data top

[Pb(C₉H₄N₂O₄)]	F(000) = 744.0
M_r = 411.34	D_x = 3.269 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2747 reflections
a = 13.127 (2) Å	θ = 2.7–28.4°
b = 9.5571 (14) Å	µ = 20.19 mm⁻¹
c = 6.7557 (10) Å	T = 273 K
β = 99.587 (2)°	Block, yellow
V = 835.7 (2) Å³	0.30 × 0.30 × 0.27 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	1458 independent reflections
Radiation source: fine-focus sealed tube	1273 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.042
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.7°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −15→15
T_min = 0.003, T_max = 0.004	k = −11→8
3954 measured reflections	l = −7→8

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.120	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0814P)²] where P = (F_o² + 2F_c²)/3
1458 reflections	(Δ/σ)_max = 0.001
133 parameters	Δρ_max = 3.24 e Å⁻³
12 restraints	Δρ_min = −2.83 e Å⁻³

Crystal data top

[Pb(C₉H₄N₂O₄)]	V = 835.7 (2) Å³
M_r = 411.34	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 13.127 (2) Å	µ = 20.19 mm⁻¹
b = 9.5571 (14) Å	T = 273 K
c = 6.7557 (10) Å	0.30 × 0.30 × 0.27 mm
β = 99.587 (2)°

Data collection top

Bruker APEXII CCD diffractometer	1458 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	1273 reflections with I > 2σ(I)
T_min = 0.003, T_max = 0.004	R_int = 0.042
3954 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	12 restraints
wR(F²) = 0.120	H-atom parameters constrained
S = 1.08	Δρ_max = 3.24 e Å⁻³
1458 reflections	Δρ_min = −2.83 e Å⁻³
133 parameters

Special details top

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. The number of independent reflections and the number of reflections used in the refinement are not the same, because we use 'omit -3 50' to enhance the'_diffrn_measured_fraction_theta_full'.

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

	x	y	z	U_iso*/U_eq
C4	0.7560 (4)	0.3072 (4)	0.2539 (9)	0.019 (2)
C5	0.6729 (3)	0.2152 (5)	0.2241 (10)	0.0164 (19)
H5	0.6058	0.2496	0.1959	0.020*
C6	0.6901 (4)	0.0717 (4)	0.2362 (9)	0.0152 (18)
C9	0.7904 (4)	0.0203 (4)	0.2783 (9)	0.0169 (19)
C1	0.8736 (3)	0.1123 (6)	0.3081 (9)	0.025 (3)
H1	0.9407	0.0779	0.3363	0.030*
C2	0.8564 (4)	0.2558 (5)	0.2959 (9)	0.021 (2)
Pb1	0.62381 (3)	0.62780 (3)	0.17812 (5)	0.0172 (2)
N1	0.7597 (7)	0.4523 (8)	0.2560 (13)	0.0252 (19)
C3	0.8566 (8)	0.4844 (11)	0.2927 (15)	0.025 (2)
H3	0.8810	0.5759	0.3003	0.029*
N2	0.9199 (8)	0.3693 (7)	0.3195 (14)	0.021 (2)
H2	0.9863	0.3690	0.3459	0.025*
C8	0.8123 (9)	−0.1314 (8)	0.3226 (17)	0.020 (2)
O4	0.8944 (6)	−0.1832 (8)	0.2949 (13)	0.036 (2)
C7	0.6000 (7)	−0.0282 (8)	0.1935 (12)	0.0146 (19)
O2	0.5921 (6)	−0.1031 (6)	0.0387 (11)	0.0220 (16)
O1	0.5389 (5)	−0.0325 (6)	0.3196 (9)	0.0184 (14)
O3	0.7406 (4)	−0.2011 (6)	0.3876 (9)	0.0167 (13)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C4	0.024 (5)	0.013 (4)	0.019 (5)	−0.001 (4)	0.002 (4)	0.001 (3)
C5	0.006 (4)	0.021 (4)	0.022 (4)	0.005 (3)	0.002 (3)	0.002 (3)
C6	0.014 (5)	0.012 (4)	0.021 (5)	−0.003 (3)	0.007 (4)	0.000 (3)
C9	0.018 (5)	0.017 (4)	0.017 (5)	−0.003 (4)	0.007 (4)	−0.001 (3)
C1	0.030 (6)	0.017 (5)	0.030 (6)	0.005 (3)	0.011 (5)	0.001 (3)
C2	0.033 (6)	0.015 (5)	0.016 (5)	−0.006 (4)	0.008 (4)	−0.002 (4)
Pb1	0.0188 (3)	0.0151 (3)	0.0172 (3)	−0.00085 (11)	0.0019 (2)	−0.00061 (10)
N1	0.026 (5)	0.021 (4)	0.029 (5)	0.001 (4)	0.008 (4)	−0.003 (3)
C3	0.029 (6)	0.016 (5)	0.028 (6)	−0.004 (4)	0.003 (5)	−0.001 (4)
N2	0.016 (5)	0.019 (4)	0.031 (5)	−0.004 (3)	0.010 (4)	−0.001 (3)
C8	0.013 (6)	0.019 (5)	0.027 (6)	0.001 (3)	0.003 (5)	−0.006 (3)
O4	0.021 (4)	0.021 (4)	0.066 (6)	0.000 (3)	0.011 (4)	0.004 (4)
C7	0.013 (5)	0.014 (4)	0.014 (5)	0.004 (3)	−0.006 (4)	0.005 (3)
O2	0.030 (4)	0.017 (3)	0.021 (4)	0.003 (3)	0.010 (3)	−0.003 (3)
O1	0.010 (3)	0.032 (3)	0.013 (3)	−0.001 (2)	0.003 (3)	0.002 (2)
O3	0.010 (3)	0.018 (3)	0.021 (3)	0.001 (2)	0.000 (3)	0.003 (2)

Geometric parameters (Å, º) top

C4—N1	1.387 (8)	Pb1—O1^iv	2.653 (6)
C4—C5	1.389 (7)	Pb1—O2ⁱ	2.746 (6)
C4—C2	1.391 (7)	N1—C3	1.292 (13)
C5—C6	1.390 (7)	C3—N2	1.371 (13)
C5—H5	0.9300	C3—H3	0.9300
C6—C9	1.390 (7)	N2—H2	0.8600
C6—C7	1.510 (10)	C8—O4	1.228 (13)
C9—C1	1.390 (7)	C8—O3	1.289 (11)
C9—C8	1.498 (9)	C7—O2	1.258 (11)
C1—C2	1.390 (7)	C7—O1	1.265 (11)
C1—H1	0.9300	O2—Pb1^iv	2.549 (7)
C2—N2	1.362 (9)	O2—Pb1^v	2.746 (6)
Pb1—N1	2.442 (8)	O1—Pb1^vi	2.630 (6)
Pb1—O3ⁱ	2.511 (6)	O1—Pb1ⁱⁱ	2.653 (6)
Pb1—O2ⁱⁱ	2.549 (7)	O3—Pb1^v	2.511 (6)
Pb1—O1ⁱⁱⁱ	2.630 (6)

N1—C4—C5	131.3 (5)	N1—Pb1—O2ⁱ	141.3 (2)
N1—C4—C2	108.7 (5)	O3ⁱ—Pb1—O2ⁱ	68.1 (2)
C5—C4—C2	120.0 (4)	O2ⁱⁱ—Pb1—O2ⁱ	112.01 (18)
C4—C5—C6	120.0 (4)	O1ⁱⁱⁱ—Pb1—O2ⁱ	118.1 (2)
C6—C5—H5	120.0	O1^iv—Pb1—O2ⁱ	89.52 (19)
C4—C5—H5	120.0	C3—N1—C4	105.7 (7)
C9—C6—C5	120.0 (4)	C3—N1—Pb1	122.6 (6)
C9—C6—C7	120.0 (4)	C4—N1—Pb1	131.4 (5)
C5—C6—C7	119.9 (4)	N1—C3—N2	113.0 (9)
C1—C9—C6	120.1 (4)	N1—C3—H3	123.5
C1—C9—C8	117.6 (5)	N2—C3—H3	123.5
C6—C9—C8	121.8 (5)	C2—N2—C3	106.1 (8)
C2—C1—H1	120.0	C2—N2—H2	126.9
C9—C1—H1	120.0	C3—N2—H2	126.9
C9—C1—C2	120.0 (4)	O4—C8—O3	123.6 (8)
N2—C2—C1	133.6 (5)	O4—C8—C9	120.2 (8)
N2—C2—C4	106.4 (5)	O3—C8—C9	116.2 (8)
C1—C2—C4	120.0 (4)	O2—C7—O1	124.6 (8)
N1—Pb1—O3ⁱ	88.3 (2)	O2—C7—C6	118.2 (8)
N1—Pb1—O2ⁱⁱ	87.7 (2)	O1—C7—C6	117.2 (7)
O3ⁱ—Pb1—O2ⁱⁱ	72.7 (2)	C7—O2—Pb1^iv	147.5 (6)
N1—Pb1—O1ⁱⁱⁱ	99.4 (2)	C7—O2—Pb1^v	105.1 (5)
O3ⁱ—Pb1—O1ⁱⁱⁱ	142.76 (18)	Pb1^iv—O2—Pb1^v	101.6 (2)
O2ⁱⁱ—Pb1—O1ⁱⁱⁱ	71.3 (2)	C7—O1—Pb1^vi	126.3 (5)
N1—Pb1—O1^iv	98.2 (2)	C7—O1—Pb1ⁱⁱ	114.1 (5)
O3ⁱ—Pb1—O1^iv	149.59 (19)	Pb1^vi—O1—Pb1ⁱⁱ	114.4 (2)
O2ⁱⁱ—Pb1—O1^iv	136.9 (2)	C8—O3—Pb1^v	123.8 (6)
O1ⁱⁱⁱ—Pb1—O1^iv	65.6 (2)

N1—C4—C5—C6	−177.8 (6)	O1ⁱⁱⁱ—Pb1—N1—C4	14.3 (7)
C2—C4—C5—C6	0.0	O1^iv—Pb1—N1—C4	−52.2 (7)
C4—C5—C6—C9	0.0	O2ⁱ—Pb1—N1—C4	−151.8 (5)
C4—C5—C6—C7	−176.9 (6)	C4—N1—C3—N2	−1.0 (11)
C5—C6—C9—C1	0.0	Pb1—N1—C3—N2	−175.9 (7)
C7—C6—C9—C1	176.9 (6)	C1—C2—N2—C3	−178.7 (6)
C5—C6—C9—C8	170.9 (7)	C4—C2—N2—C3	0.4 (9)
C7—C6—C9—C8	−12.2 (8)	N1—C3—N2—C2	0.4 (12)
C6—C9—C1—C2	0.0	C1—C9—C8—O4	−32.8 (12)
C8—C9—C1—C2	−171.2 (7)	C6—C9—C8—O4	156.1 (8)
C9—C1—C2—N2	179.1 (9)	C1—C9—C8—O3	147.9 (7)
C9—C1—C2—C4	0.0	C6—C9—C8—O3	−23.2 (11)
N1—C4—C2—N2	−1.1 (7)	C5—C6—C7—O2	112.1 (7)
C5—C4—C2—N2	−179.3 (6)	C9—C6—C7—O2	−64.9 (8)
N1—C4—C2—C1	178.2 (5)	C5—C6—C7—O1	−69.5 (8)
C5—C4—C2—C1	0.0	C9—C6—C7—O1	113.6 (7)
C5—C4—N1—C3	179.3 (6)	O1—C7—O2—Pb1^iv	150.4 (8)
C2—C4—N1—C3	1.3 (8)	C6—C7—O2—Pb1^iv	−31.3 (15)
C5—C4—N1—Pb1	−6.5 (9)	O1—C7—O2—Pb1^v	−65.2 (9)
C2—C4—N1—Pb1	175.5 (5)	C6—C7—O2—Pb1^v	113.1 (6)
O3ⁱ—Pb1—N1—C3	−29.0 (8)	O2—C7—O1—Pb1^vi	−94.0 (9)
O2ⁱⁱ—Pb1—N1—C3	−101.8 (8)	C6—C7—O1—Pb1^vi	87.7 (7)
O1ⁱⁱⁱ—Pb1—N1—C3	−172.4 (7)	O2—C7—O1—Pb1ⁱⁱ	113.2 (8)
O1^iv—Pb1—N1—C3	121.2 (8)	C6—C7—O1—Pb1ⁱⁱ	−65.2 (7)
O2ⁱ—Pb1—N1—C3	21.6 (10)	O4—C8—O3—Pb1^v	−74.3 (13)
O3ⁱ—Pb1—N1—C4	157.6 (7)	C9—C8—O3—Pb1^v	105.0 (7)
O2ⁱⁱ—Pb1—N1—C4	84.8 (7)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O4^vii	0.86	2.02	2.723 (12)	138

Symmetry code: (vii) −x+2, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Pb(C₉H₄N₂O₄)]
M_r	411.34
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	273
a, b, c (Å)	13.127 (2), 9.5571 (14), 6.7557 (10)
β (°)	99.587 (2)
V (Å³)	835.7 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	20.19
Crystal size (mm)	0.30 × 0.30 × 0.27

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.003, 0.004
No. of measured, independent and observed [I > 2σ(I)] reflections	3954, 1458, 1273
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.120, 1.08
No. of reflections	1458
No. of parameters	133
No. of restraints	12
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	3.24, −2.83

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O4ⁱ	0.86	2.02	2.723 (12)	138

Symmetry code: (i) −x+2, y+1/2, −z+1/2.

Acknowledgements

The authors acknowledge the Chan Xue Yan Cooperative Special Project of Guangdong Province and the Ministry of Science and Technology of PRC (project No. 2010B090400184).

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