μ-4,4′-Bipyridine-κ2N:N′-bis­[bis­(2-chloro­benzoato-κ2O,O′)lead(II)]

Feng, T.-J.

doi:10.1107/S1600536811022422

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 7| July 2011| Page m935

doi:10.1107/S1600536811022422

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μ-4,4′-Bipyridine-κ²N:N′-bis[bis(2-chlorobenzoato-κ²O,O′)lead(II)]

Tian-Jun Feng ^a ^*

^aCollege of Mathematics, Physics and Software Engineering, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China
^*Correspondence e-mail: fengtj707@126.com

(Received 21 May 2011; accepted 9 June 2011; online 18 June 2011)

In the title dinuclear complex, [Pb₂(C₇H₄ClO₂)₄(C₁₀H₈N₂)], the Pb^II atom is five-coordinated by four carboxylate O atoms from two 2-chlorobenzoate ligands and one N atom from a bridging 4,4′-bipyridine (4,4′-bpy) ligand, displaying a hemi-directed coordination. The 4,4′-bpy ligand has an inversion center at the mid-point of the central C—C bond. The empty side of the metal ion is capped by two carboxylate O atoms from a neighboring molecule, with weak Pb⋯O contacts [Pb⋯O = 3.069 (2) and 3.071 (3) Å]. The crystal structure is stabilized by C—H⋯O hydrogen bonds and π–π stacking interactions between the benzene and pyridine rings [centroid–centroid distance = 3.749 (3) Å].

Related literature

For general background to 2-chlorobenzoate complexes, see: Gomez & Corbella (2009 ); Motokawa et al. (2010 ). For general background to 4,4′-bipyridine complexes, see: Biradha et al. (2006 ). For hemi- and holo-directed geometries of lead(II) complexes, see: Shimoni-Livny et al. (1998 ).

Experimental

Crystal data

[Pb₂(C₇H₄ClO₂)₄(C₁₀H₈N₂)]
M_r = 1192.79
Orthorhombic, P b c a
a = 21.9370 (13) Å
b = 7.4569 (5) Å
c = 23.2379 (14) Å
V = 3801.3 (4) Å³
Z = 4
Mo Kα radiation
μ = 9.18 mm⁻¹
T = 296 K
0.30 × 0.28 × 0.22 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.092, T_max = 0.145
15375 measured reflections
3398 independent reflections
2712 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.026
wR(F²) = 0.081
S = 1.09
3398 reflections
244 parameters
H-atom parameters constrained
Δρ_max = 0.84 e Å⁻³
Δρ_min = −0.53 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C15—H15⋯O1ⁱ	0.93	2.40	3.239 (7)	150
C16—H16⋯O2ⁱⁱ	0.93	2.55	3.361 (6)	146
C19—H19⋯O4	0.93	2.39	3.026 (5)	125
Symmetry codes: (i) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ ; (ii) x, y+1, z.

Data collection: APEX2 (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) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811022422/hy2436sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811022422/hy2436Isup2.hkl

checkCIF report

Comment top

In the structural investigation of 2-chlorobenzoate complexes, it has been found that 2-chlorobenzoic acid (2-Hcbz) functions as a multidentate ligand with versatile binding and coordination modes (Gomez & Corbella, 2009; Motokawa et al., 2010). As is well known, 4,4'-bipyridine (4,4'-bpy) ligand can act in bidentate bridging or monodentate terminal modes (Biradha et al., 2006). In this paper, we report the crystal structure of the title compound, a new Pb(II) complex obtained by the reaction of 2-Hcbz, 4,4'-bpy and lead(II) acetate in an alkaline aqueous solution.

As depicted in Fig. 1, the Pb^II atom is coordinated by four O atoms from two 2-cbz ligands and one N atom from a µ-4,4'-bpy ligand. The coordination environment of the Pb^II atom is hemidirected. The empty sapce around the metal ion is filled by the stereochemically active 6S² electron pair (Shimoni-Livny et al., 1998) and two Pb···O contacts [Pb1···O1ⁱ = 3.069 (2), Pb1···O3ⁱ = 3.071 (3) Å. Symmetry code: (i) 1/2-x, 1/2+y, z]. The µ-4,4'-bpy ligand, having an inversion center at the mid-point of the central C—C bond, bridges two Pb atoms, with a Pb1···Pb1ⁱⁱ distance of 12.073 (3) Å [symmetry code: (ii) -x, 3-y, -z]. The interactions of the structural components are governed by Pb···O contacts, C—H···O hydrogen bonds (Table 1) and π–π stacking interactions. The centroid–centroid distance between the benzene ring of a 2-cbz ligand and the pyridine ring of a 4,4'-bpy at (x, -1+y, z) is 3.749 (3) Å (Fig. 2).

Related literature top

For general background to 2-chlorobenzoate complexes, see: Gomez & Corbella (2009); Motokawa et al. (2010). For general background to 4,4'-bipyridine complexes, see: Biradha et al. (2006). For hemi- and holo-directed geometries of lead(II) complexes, see: Shimoni-Livny et al. (1998).

Experimental top

A mixture of lead acetate (1 mmol, 0.325 g), 2-Hcbz (1 mmol, 0.156 g), 4,4'-bpy (1 mmol, 0.156 g), NaOH (1.5 mmol, 0.06 g) and H₂O (12 ml) was placed in a 23 ml Teflon-lined reactor, which was heated at 433 K for three days and then cooled to room temperature at a rate of 10 K h^-1. The colorless crystals obtained were washed with water and dried in air.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids. H atoms were omitted for clarity. [Symmetry code: (i) -x, 3-y, -z.]
	Fig. 2. A packing view of the title compound. π–π interactions are shown as dashed lines.

µ-4,4'-Bipyridine-κ²N:N'-bis[bis(2-chlorobenzoato- κ²O,O')lead(II)] top

Crystal data top

[Pb₂(C₇H₄ClO₂)₄(C₁₀H₈N₂)]	F(000) = 2248
M_r = 1192.79	D_x = 2.084 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 5300 reflections
a = 21.9370 (13) Å	θ = 1.3–28.0°
b = 7.4569 (5) Å	µ = 9.18 mm⁻¹
c = 23.2379 (14) Å	T = 296 K
V = 3801.3 (4) Å³	Block, colorless
Z = 4	0.30 × 0.28 × 0.22 mm

Data collection top

Bruker APEXII CCD diffractometer	3398 independent reflections
Radiation source: fine-focus sealed tube	2712 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
ϕ and ω scans	θ_max = 25.2°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −25→26
T_min = 0.092, T_max = 0.145	k = −8→8
15375 measured reflections	l = −27→19

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)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.081	H-atom parameters constrained
S = 1.09	w = 1/[σ²(F_o²) + (0.0403P)² + 6.2959P] where P = (F_o² + 2F_c²)/3
3398 reflections	(Δ/σ)_max = 0.001
244 parameters	Δρ_max = 0.84 e Å⁻³
0 restraints	Δρ_min = −0.53 e Å⁻³

Crystal data top

[Pb₂(C₇H₄ClO₂)₄(C₁₀H₈N₂)]	V = 3801.3 (4) Å³
M_r = 1192.79	Z = 4
Orthorhombic, Pbca	Mo Kα radiation
a = 21.9370 (13) Å	µ = 9.18 mm⁻¹
b = 7.4569 (5) Å	T = 296 K
c = 23.2379 (14) Å	0.30 × 0.28 × 0.22 mm

Data collection top

Bruker APEXII CCD diffractometer	3398 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2712 reflections with I > 2σ(I)
T_min = 0.092, T_max = 0.145	R_int = 0.032
15375 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.026	0 restraints
wR(F²) = 0.081	H-atom parameters constrained
S = 1.09	Δρ_max = 0.84 e Å⁻³
3398 reflections	Δρ_min = −0.53 e Å⁻³
244 parameters

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

	x	y	z	U_iso*/U_eq
C1	0.1794 (3)	0.7076 (9)	−0.1258 (3)	0.0427 (15)
C2	0.1528 (3)	0.8251 (10)	−0.1646 (3)	0.0552 (18)
C3	0.1478 (4)	0.7786 (12)	−0.2219 (3)	0.068 (2)
H3	0.1289	0.8564	−0.2476	0.082*
C4	0.1705 (4)	0.6187 (13)	−0.2411 (3)	0.070 (2)
H4	0.1692	0.5922	−0.2802	0.084*
C5	0.1949 (4)	0.4974 (16)	−0.2036 (4)	0.082 (3)
H5	0.2071	0.3840	−0.2157	0.098*
C6	0.2009 (3)	0.5513 (11)	−0.1462 (3)	0.0555 (19)
H6	0.2208	0.4748	−0.1208	0.067*
C7	0.1912 (3)	0.7545 (9)	−0.0634 (3)	0.0405 (14)
C8	0.0956 (3)	0.5487 (8)	0.1402 (2)	0.0389 (14)
C9	0.1121 (3)	0.3828 (10)	0.1618 (3)	0.0517 (17)
C10	0.0715 (4)	0.2756 (12)	0.1901 (3)	0.075 (2)
H10	0.0851	0.1680	0.2058	0.090*
C11	0.0125 (4)	0.3208 (13)	0.1958 (4)	0.080 (3)
H11	−0.0153	0.2422	0.2124	0.096*
C12	−0.0058 (3)	0.4903 (11)	0.1761 (3)	0.060 (2)
H12	−0.0458	0.5282	0.1815	0.071*
C13	0.0351 (3)	0.5999 (10)	0.1490 (3)	0.0498 (17)
H13	0.0222	0.7116	0.1360	0.060*
C14	0.1369 (3)	0.6803 (9)	0.1091 (2)	0.0421 (15)
C15	0.1235 (3)	1.3106 (9)	−0.0034 (3)	0.059 (2)
H15	0.1630	1.3251	−0.0172	0.071*
C16	0.0814 (3)	1.4422 (9)	−0.0149 (4)	0.060 (2)
H16	0.0930	1.5416	−0.0364	0.072*
C17	0.0229 (2)	1.4299 (7)	0.0047 (3)	0.0343 (13)
C18	0.0088 (3)	1.2696 (9)	0.0332 (3)	0.0503 (18)
H18	−0.0308	1.2478	0.0457	0.060*
C19	0.0541 (3)	1.1442 (9)	0.0427 (3)	0.0547 (18)
H19	0.0443	1.0388	0.0620	0.066*
Cl1	0.12558 (15)	1.0350 (3)	−0.14483 (12)	0.1014 (9)
Cl2	0.18725 (7)	0.3008 (3)	0.15571 (9)	0.0618 (5)
N1	0.1109 (2)	1.1684 (7)	0.0254 (2)	0.0441 (12)
O1	0.23874 (19)	0.7055 (6)	−0.04024 (17)	0.0497 (12)
O2	0.15049 (19)	0.8395 (6)	−0.03665 (17)	0.0472 (11)
O3	0.1874 (2)	0.6329 (7)	0.0914 (3)	0.0665 (16)
O4	0.1161 (2)	0.8292 (7)	0.1003 (3)	0.0747 (16)
Pb1	0.197071 (9)	0.95216 (3)	0.044368 (10)	0.03659 (10)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.035 (3)	0.051 (4)	0.042 (3)	−0.010 (3)	−0.002 (3)	0.002 (3)
C2	0.068 (4)	0.047 (4)	0.051 (4)	0.012 (3)	−0.016 (3)	0.012 (3)
C3	0.077 (5)	0.076 (6)	0.051 (4)	0.001 (4)	−0.019 (4)	0.024 (4)
C4	0.075 (5)	0.086 (6)	0.049 (4)	−0.017 (5)	−0.003 (4)	−0.001 (5)
C5	0.081 (6)	0.112 (8)	0.053 (5)	0.003 (5)	−0.001 (4)	−0.029 (5)
C6	0.057 (4)	0.062 (5)	0.048 (4)	0.002 (4)	−0.002 (3)	−0.002 (4)
C7	0.041 (3)	0.044 (4)	0.037 (3)	−0.013 (3)	0.001 (3)	0.006 (3)
C8	0.042 (3)	0.044 (3)	0.031 (3)	−0.019 (3)	−0.001 (3)	0.001 (3)
C9	0.054 (4)	0.063 (4)	0.038 (3)	0.001 (4)	0.001 (3)	0.010 (3)
C10	0.075 (5)	0.081 (6)	0.069 (5)	−0.015 (5)	0.003 (4)	0.032 (5)
C11	0.061 (5)	0.096 (7)	0.083 (6)	−0.007 (5)	0.024 (4)	0.024 (5)
C12	0.040 (4)	0.062 (5)	0.077 (5)	0.000 (3)	0.014 (4)	0.008 (4)
C13	0.045 (3)	0.057 (4)	0.048 (4)	0.012 (3)	0.006 (3)	0.001 (3)
C14	0.049 (4)	0.044 (4)	0.034 (3)	−0.001 (3)	−0.007 (3)	0.008 (3)
C15	0.040 (4)	0.047 (4)	0.090 (6)	0.009 (3)	0.011 (4)	0.021 (4)
C16	0.041 (4)	0.049 (4)	0.089 (5)	0.020 (3)	0.018 (4)	0.031 (4)
C17	0.029 (3)	0.031 (3)	0.043 (3)	−0.010 (2)	−0.004 (2)	0.000 (3)
C18	0.031 (3)	0.031 (3)	0.089 (5)	0.008 (3)	0.008 (3)	0.014 (3)
C19	0.045 (4)	0.026 (3)	0.093 (5)	−0.001 (3)	0.008 (3)	0.018 (4)
Cl1	0.149 (2)	0.0533 (13)	0.1017 (18)	0.0321 (15)	−0.0395 (17)	0.0097 (13)
Cl2	0.0521 (10)	0.0578 (11)	0.0754 (12)	0.0092 (8)	0.0001 (8)	0.0201 (10)
N1	0.042 (3)	0.039 (3)	0.052 (3)	0.015 (2)	−0.003 (2)	0.001 (3)
O1	0.040 (2)	0.064 (3)	0.045 (2)	0.013 (2)	−0.0075 (19)	0.002 (2)
O2	0.041 (2)	0.051 (3)	0.049 (3)	0.013 (2)	−0.0015 (19)	−0.011 (2)
O3	0.047 (3)	0.035 (3)	0.117 (5)	0.010 (2)	0.032 (3)	0.021 (3)
O4	0.061 (3)	0.057 (3)	0.106 (4)	0.008 (3)	0.024 (3)	0.040 (3)
Pb1	0.03377 (14)	0.03153 (15)	0.04447 (15)	0.00209 (9)	−0.00447 (9)	0.00210 (10)

Geometric parameters (Å, º) top

C1—C6	1.344 (10)	C11—H11	0.9300
C1—C2	1.386 (9)	C12—C13	1.367 (10)
C1—C7	1.512 (8)	C12—H12	0.9300
C2—C3	1.381 (10)	C13—H13	0.9300
C2—Cl1	1.737 (8)	C14—O4	1.217 (8)
C3—C4	1.366 (12)	C14—O3	1.234 (7)
C3—H3	0.9300	C15—N1	1.284 (8)
C4—C5	1.365 (13)	C15—C16	1.373 (9)
C4—H4	0.9300	C15—H15	0.9300
C5—C6	1.400 (11)	C16—C17	1.365 (8)
C5—H5	0.9300	C16—H16	0.9300
C6—H6	0.9300	C17—C18	1.402 (8)
C7—O1	1.230 (7)	C17—C17ⁱ	1.467 (11)
C7—O2	1.259 (7)	C18—C19	1.383 (9)
C8—C9	1.383 (9)	C18—H18	0.9300
C8—C13	1.396 (8)	C19—N1	1.322 (8)
C8—C14	1.518 (8)	C19—H19	0.9300
C9—C10	1.364 (10)	N1—Pb1	2.523 (5)
C9—Cl2	1.764 (7)	O2—Pb1	2.301 (4)
C10—C11	1.344 (11)	O3—Pb1	2.629 (5)
C10—H10	0.9300	O4—Pb1	2.384 (5)
C11—C12	1.403 (12)

C6—C1—C2	117.8 (6)	C11—C12—H12	120.0
C6—C1—C7	118.6 (6)	C12—C13—C8	121.8 (6)
C2—C1—C7	123.3 (6)	C12—C13—H13	119.1
C3—C2—C1	120.2 (7)	C8—C13—H13	119.1
C3—C2—Cl1	117.0 (5)	O4—C14—O3	122.8 (6)
C1—C2—Cl1	122.9 (5)	O4—C14—C8	116.5 (6)
C4—C3—C2	120.3 (7)	O3—C14—C8	120.6 (6)
C4—C3—H3	119.9	N1—C15—C16	123.1 (6)
C2—C3—H3	119.9	N1—C15—H15	118.4
C3—C4—C5	120.9 (8)	C16—C15—H15	118.4
C3—C4—H4	119.5	C17—C16—C15	121.3 (6)
C5—C4—H4	119.5	C17—C16—H16	119.3
C4—C5—C6	117.0 (9)	C15—C16—H16	119.3
C4—C5—H5	121.5	C16—C17—C18	115.0 (5)
C6—C5—H5	121.5	C16—C17—C17ⁱ	123.2 (6)
C1—C6—C5	123.6 (8)	C18—C17—C17ⁱ	121.7 (6)
C1—C6—H6	118.2	C19—C18—C17	119.5 (5)
C5—C6—H6	118.2	C19—C18—H18	120.2
O1—C7—O2	122.3 (6)	C17—C18—H18	120.2
O1—C7—C1	119.7 (6)	N1—C19—C18	122.5 (6)
O2—C7—C1	117.9 (5)	N1—C19—H19	118.8
C9—C8—C13	116.1 (6)	C18—C19—H19	118.8
C9—C8—C14	126.5 (6)	C15—N1—C19	118.3 (6)
C13—C8—C14	117.3 (6)	C15—N1—Pb1	117.3 (4)
C10—C9—C8	121.9 (7)	C19—N1—Pb1	124.4 (4)
C10—C9—Cl2	116.4 (6)	C7—O2—Pb1	105.9 (4)
C8—C9—Cl2	121.7 (5)	C14—O3—Pb1	87.2 (4)
C11—C10—C9	121.9 (8)	C14—O4—Pb1	99.4 (4)
C11—C10—H10	119.0	O2—Pb1—O4	88.57 (19)
C9—C10—H10	119.0	O2—Pb1—N1	75.99 (16)
C10—C11—C12	118.0 (8)	O4—Pb1—N1	77.48 (18)
C10—C11—H11	121.0	O2—Pb1—O3	88.51 (18)
C12—C11—H11	121.0	O4—Pb1—O3	50.55 (15)
C13—C12—C11	120.1 (7)	N1—Pb1—O3	126.24 (15)
C13—C12—H12	120.0

Symmetry code: (i) −x, −y+3, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15···O1ⁱⁱ	0.93	2.40	3.239 (7)	150
C16—H16···O2ⁱⁱⁱ	0.93	2.55	3.361 (6)	146
C19—H19···O4	0.93	2.39	3.026 (5)	125

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

Experimental details

Crystal data
Chemical formula	[Pb₂(C₇H₄ClO₂)₄(C₁₀H₈N₂)]
M_r	1192.79
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	296
a, b, c (Å)	21.9370 (13), 7.4569 (5), 23.2379 (14)
V (Å³)	3801.3 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	9.18
Crystal size (mm)	0.30 × 0.28 × 0.22

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.092, 0.145
No. of measured, independent and observed [I > 2σ(I)] reflections	15375, 3398, 2712
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.026, 0.081, 1.09
No. of reflections	3398
No. of parameters	244
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.84, −0.53

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15···O1ⁱ	0.93	2.40	3.239 (7)	150
C16—H16···O2ⁱⁱ	0.93	2.55	3.361 (6)	146
C19—H19···O4	0.93	2.39	3.026 (5)	125

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

Acknowledgements

The authors acknowledge Lanzhou Jiaotong University for supporting this work.

References

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