Hexa-μ-chlorido-μ₄-oxido-tetra­kis­({1-[(pyridin-2-yl)meth­yl]-1H-benzimidazole-κN ³}copper(II))

Abstract

The title tetra­nuclear complex, [Cu₄Cl₆O(C₁₃H₁₁N₃)₄], features a tetra­hedral arrangement of copper(II) ions bonded to the central O atom (site symmetry ). Each of the six edges of the Cu₄ tetra­hedron is bridged by a chloride ion (one of which has site symmetry 2), so that each copper ion is linked to the other three metal ions through the central O atom and through three separate chloride-ion bridges. The fifth coord­ination position, located on the central Cu—O axis on the outside of the cluster, is occupied by an N atom of the mono­dentate 1-(pyridin-2-ylmeth­yl)-1H-benzimidazole ligand. The resulting coordination geometry of the metal ion is a distorted trigonal bipyramid with the O and N atoms in the axial positions. The dihedral angle between the benzimidazole ring system and the pendant pyridine ring is 61.0 (2)°.

Related literature

For background to polynuclear copper halides, see: Willett (1991 ▶); Chivers et al. (2005 ▶); Li et al. (2009 ▶).

Experimental

Crystal data

• [Cu₄Cl₆O(C₁₃H₁₁N₃)₄]

• M _r = 1319.85

• Tetragonal,

• a = 13.8532 (12) Å

• c = 14.507 (3) Å

• V = 2784.1 (6) ų

• Z = 2

• Mo Kα radiation

• μ = 1.85 mm⁻¹

• T = 294 K

• 0.25 × 0.23 × 0.20 mm

Data collection

• Rigaku Mercury CCD diffractometer

• Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 ▶) T _min = 0.637, T _max = 0.691

• 7149 measured reflections

• 2467 independent reflections

• 2178 reflections with I > 2σ(I)

• R _int = 0.033

Refinement

• R[F ² > 2σ(F ²)] = 0.028

• wR(F ²) = 0.062

• S = 1.06

• 2467 reflections

• 170 parameters

• H-atom parameters constrained

• Δρ_max = 0.34 e Å⁻³

• Δρ_min = −0.17 e Å⁻³

• Absolute structure: Flack (1983) ▶, 1172 Friedel pairs

• Flack parameter: 0.005 (15)

Data collection: CrystalClear (Rigaku/MSC, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; 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. Selected bond lengths (Å).

Cu1—O1	1.9199 (4)
Cu1—N3	1.974 (3)
Cu1—Cl1i	2.3961 (10)
Cu1—Cl1	2.4192 (10)
Cu1—Cl2	2.4263 (10)

Symmetry code: (i) .

supplementary crystallographic information

Comment

Copper(II) halide framework materials have attracted much attention for their interesting magnetic properties and structural richness (Willett et al., 1991). The most commonly employed technique to modulate the inorganic network involves the direct addition of an organic ligand as a templating reagent (Chivers et al., 2005). benzimidazole has been well used in crystal engineering, and a large number of benzimidazole ligands have been extensively studied (Li et al., 2009). The reaction of CuCl₂ with the benzimidazole-pyridine ligand (L) affords a tetranuclear molecule [(Cu₄O)Cl₆(L)₄], (I). The crystal structure was elucidated by X-ray diffraction analysis.

Experimental

To a solution of L (0.12 mmol, 25 mg) dissolved in CH₃CN (9 ml), a solution of CuCl₂^.6H₂O (0.12 mmol, 28.9 mg) in H₂O (9 ml) was added under stirring in a few minutes. The solution was left to stand at room temperature. Brown blocks of (I) were obtained after several days with solvent evaporation. Yield: ~20% (based on L).

Refinement

C-bound H atoms were positioned geometrically and refined in the riding-model approximation, with C—H = 0.93Å and U_iso(H) = 1.2Ueq.

Figures

Fig. 1.

The molecular structure of (I). Displacement ellipsoids are drawn at the 30% probability level and H atoms are removed for clarity. [symmetry code: (A) -y + 1, x, -z; (B) y, -x + 1, -z; (C) -x + 1, -y + 1, z].

Fig. 2.

The crystal packing for (I) viewed along the c axis.

Crystal data

[Cu4Cl6O(C13H11N3)4]	Dx = 1.574 Mg m−3
Mr = 1319.85	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4	Cell parameters from 3492 reflections
a = 13.8532 (12) Å	θ = 2.8–25.3°
c = 14.507 (3) Å	µ = 1.85 mm−1
V = 2784.1 (6) Å3	T = 294 K
Z = 2	Block, brown
F(000) = 1332	0.25 × 0.23 × 0.20 mm

Data collection

Rigaku Mercury CCD diffractometer	2467 independent reflections
Radiation source: fine-focus sealed tube	2178 reflections with I > 2σ(I)
graphite	Rint = 0.033
Detector resolution: 9 pixels mm-1	θmax = 25.0°, θmin = 2.0°
ω scans	h = −14→16
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	k = −16→14
Tmin = 0.637, Tmax = 0.691	l = −17→17
7149 measured reflections

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)] = 0.028	H-atom parameters constrained
wR(F2) = 0.062	w = 1/[σ2(Fo2) + (0.0286P)2] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max = 0.001
2467 reflections	Δρmax = 0.34 e Å−3
170 parameters	Δρmin = −0.17 e Å−3
0 restraints	Absolute structure: Flack (1983), 1172 Friedel pairs
0 constraints	Flack parameter: 0.005 (15)
Primary atom site location: structure-invariant direct methods

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cu1	0.42929 (3)	0.41004 (3)	0.07467 (3)	0.03400 (12)
Cl1	0.28847 (6)	0.47255 (6)	−0.00384 (7)	0.0473 (2)
Cl2	0.5000	0.5000	0.20129 (8)	0.0637 (4)
N3	0.3550 (2)	0.3189 (2)	0.1515 (2)	0.0412 (7)
C1	0.3592 (3)	0.2243 (3)	0.1520 (3)	0.0498 (10)
H1	0.3992	0.1887	0.1133	0.060*
C2	0.2867 (3)	0.3436 (3)	0.2180 (2)	0.0485 (10)
C7	0.2518 (3)	0.2588 (3)	0.2595 (3)	0.0533 (10)
N2	0.2998 (3)	0.1839 (2)	0.2144 (2)	0.0548 (9)
C6	0.1844 (3)	0.2627 (4)	0.3322 (3)	0.0736 (15)
H6	0.1636	0.2068	0.3616	0.088*
C3	0.2513 (3)	0.4325 (3)	0.2461 (3)	0.0663 (13)
H3	0.2726	0.4892	0.2184	0.080*
C4	0.1837 (4)	0.4350 (4)	0.3161 (4)	0.0844 (16)
H4	0.1593	0.4940	0.3359	0.101*
C5	0.1515 (4)	0.3495 (5)	0.3574 (4)	0.0899 (18)
H5	0.1056	0.3532	0.4040	0.108*
C8	0.2900 (4)	0.0806 (3)	0.2368 (3)	0.0755 (15)
H8A	0.2343	0.0721	0.2764	0.091*
H8B	0.3465	0.0601	0.2711	0.091*
O1	0.5000	0.5000	0.0000	0.0292 (9)
C9	0.2789 (3)	0.0170 (3)	0.1543 (3)	0.0563 (10)
C10	0.1944 (4)	−0.0195 (4)	0.1286 (4)	0.0846 (16)
H10	0.1380	−0.0038	0.1600	0.102*
N1	0.3632 (4)	−0.0017 (4)	0.1100 (4)	0.1075 (18)
C12	0.2815 (9)	−0.1018 (5)	0.0115 (5)	0.128 (3)
H12	0.2863	−0.1449	−0.0374	0.154*
C11	0.1926 (7)	−0.0858 (5)	0.0487 (5)	0.116 (2)
H11	0.1364	−0.1138	0.0261	0.139*
C13	0.3600 (8)	−0.0601 (5)	0.0405 (6)	0.140 (4)
H13	0.4172	−0.0730	0.0093	0.168*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cu1	0.0374 (2)	0.0322 (2)	0.03237 (19)	−0.00702 (17)	0.0024 (2)	0.00311 (19)
Cl1	0.0319 (5)	0.0549 (5)	0.0552 (5)	−0.0045 (4)	−0.0026 (4)	0.0094 (5)
Cl2	0.0911 (11)	0.0707 (10)	0.0294 (6)	−0.0472 (9)	0.000	0.000
N3	0.0419 (18)	0.0393 (18)	0.0425 (16)	−0.0130 (14)	0.0009 (14)	0.0065 (14)
C1	0.061 (3)	0.045 (2)	0.043 (2)	−0.0162 (19)	−0.006 (2)	0.0044 (19)
C2	0.045 (2)	0.058 (3)	0.042 (2)	−0.0166 (19)	−0.0002 (18)	0.007 (2)
C7	0.054 (2)	0.060 (3)	0.045 (2)	−0.021 (2)	0.001 (2)	0.010 (2)
N2	0.068 (2)	0.048 (2)	0.048 (2)	−0.0231 (17)	−0.0028 (18)	0.0152 (17)
C6	0.064 (3)	0.096 (4)	0.061 (3)	−0.035 (3)	0.005 (2)	0.030 (3)
C3	0.073 (3)	0.060 (3)	0.066 (3)	−0.015 (2)	0.021 (3)	0.003 (2)
C4	0.083 (4)	0.080 (4)	0.091 (4)	−0.003 (3)	0.037 (3)	0.002 (3)
C5	0.084 (4)	0.102 (5)	0.084 (4)	−0.016 (3)	0.040 (3)	0.002 (3)
C8	0.108 (4)	0.054 (3)	0.065 (3)	−0.030 (3)	−0.008 (3)	0.021 (2)
O1	0.0293 (14)	0.0293 (14)	0.029 (2)	0.000	0.000	0.000
C9	0.064 (3)	0.042 (2)	0.064 (3)	−0.002 (2)	0.010 (2)	0.020 (2)
C10	0.093 (4)	0.081 (4)	0.081 (4)	−0.020 (3)	0.010 (3)	0.001 (3)
N1	0.107 (4)	0.085 (3)	0.130 (5)	0.035 (3)	0.033 (3)	0.025 (3)
C12	0.229 (11)	0.066 (4)	0.090 (5)	−0.007 (6)	0.033 (7)	0.000 (4)
C11	0.158 (7)	0.092 (5)	0.097 (5)	−0.030 (5)	−0.005 (5)	0.008 (4)
C13	0.202 (10)	0.064 (5)	0.154 (8)	0.052 (5)	0.079 (7)	0.012 (5)

Geometric parameters (Å, °)

Cu1—O1	1.9199 (4)	C4—C5	1.400 (7)
Cu1—N3	1.974 (3)	C4—H4	0.9300
Cu1—Cl1i	2.3961 (10)	C5—H5	0.9300
Cu1—Cl1	2.4192 (10)	C8—C9	1.494 (7)
Cu1—Cl2	2.4263 (10)	C8—H8A	0.9700
Cl1—Cu1ii	2.3961 (9)	C8—H8B	0.9700
Cl2—Cu1iii	2.4263 (10)	O1—Cu1iii	1.9199 (4)
N3—C1	1.313 (4)	O1—Cu1i	1.9199 (4)
N3—C2	1.394 (5)	O1—Cu1ii	1.9199 (4)
C1—N2	1.345 (5)	C9—C10	1.328 (6)
C1—H1	0.9300	C9—N1	1.358 (6)
C2—C3	1.386 (6)	C10—C11	1.480 (8)
C2—C7	1.407 (5)	C10—H10	0.9300
C7—N2	1.395 (6)	N1—C13	1.293 (9)
C7—C6	1.409 (6)	C12—C13	1.301 (12)
N2—C8	1.474 (5)	C12—C11	1.362 (10)
C6—C5	1.337 (8)	C12—H12	0.9300
C6—H6	0.9300	C11—H11	0.9300
C3—C4	1.382 (6)	C13—H13	0.9300
C3—H3	0.9300
O1—Cu1—N3	179.14 (9)	C3—C4—H4	119.7
O1—Cu1—Cl1i	85.68 (3)	C5—C4—H4	119.7
N3—Cu1—Cl1i	95.10 (9)	C6—C5—C4	122.3 (5)
O1—Cu1—Cl1	85.03 (3)	C6—C5—H5	118.8
N3—Cu1—Cl1	94.25 (9)	C4—C5—H5	118.8
Cl1i—Cu1—Cl1	120.483 (17)	N2—C8—C9	113.9 (4)
O1—Cu1—Cl2	83.56 (2)	N2—C8—H8A	108.8
N3—Cu1—Cl2	96.40 (9)	C9—C8—H8A	108.8
Cl1i—Cu1—Cl2	117.17 (3)	N2—C8—H8B	108.8
Cl1—Cu1—Cl2	119.88 (3)	C9—C8—H8B	108.8
Cu1ii—Cl1—Cu1	80.69 (3)	H8A—C8—H8B	107.7
Cu1—Cl2—Cu1iii	81.58 (4)	Cu1iii—O1—Cu1i	108.564 (12)
C1—N3—C2	105.8 (3)	Cu1iii—O1—Cu1	111.30 (2)
C1—N3—Cu1	128.2 (3)	Cu1i—O1—Cu1	108.564 (12)
C2—N3—Cu1	126.0 (2)	Cu1iii—O1—Cu1ii	108.564 (12)
N3—C1—N2	113.1 (4)	Cu1i—O1—Cu1ii	111.30 (2)
N3—C1—H1	123.5	Cu1—O1—Cu1ii	108.564 (12)
N2—C1—H1	123.5	C10—C9—N1	123.5 (5)
C3—C2—N3	131.4 (3)	C10—C9—C8	122.7 (5)
C3—C2—C7	119.6 (4)	N1—C9—C8	113.8 (5)
N3—C2—C7	108.9 (4)	C9—C10—C11	118.1 (6)
N2—C7—C2	104.9 (4)	C9—C10—H10	121.0
N2—C7—C6	134.1 (4)	C11—C10—H10	121.0
C2—C7—C6	121.0 (5)	C13—N1—C9	117.3 (7)
C1—N2—C7	107.4 (3)	C13—C12—C11	123.7 (8)
C1—N2—C8	127.5 (4)	C13—C12—H12	118.1
C7—N2—C8	125.1 (4)	C11—C12—H12	118.1
C5—C6—C7	117.8 (4)	C12—C11—C10	113.3 (7)
C5—C6—H6	121.1	C12—C11—H11	123.3
C7—C6—H6	121.1	C10—C11—H11	123.3
C4—C3—C2	118.6 (4)	N1—C13—C12	123.9 (8)
C4—C3—H3	120.7	N1—C13—H13	118.0
C2—C3—H3	120.7	C12—C13—H13	118.0
C3—C4—C5	120.6 (5)
O1—Cu1—Cl1—Cu1ii	−1.10 (2)	N2—C7—C6—C5	−178.9 (5)
N3—Cu1—Cl1—Cu1ii	178.42 (9)	C2—C7—C6—C5	3.0 (7)
Cl1i—Cu1—Cl1—Cu1ii	−83.12 (4)	N3—C2—C3—C4	−178.9 (4)
Cl2—Cu1—Cl1—Cu1ii	78.54 (4)	C7—C2—C3—C4	1.4 (7)
O1—Cu1—Cl2—Cu1iii	0.0	C2—C3—C4—C5	−0.2 (8)
N3—Cu1—Cl2—Cu1iii	−179.13 (9)	C7—C6—C5—C4	−1.8 (9)
Cl1i—Cu1—Cl2—Cu1iii	81.77 (3)	C3—C4—C5—C6	0.5 (9)
Cl1—Cu1—Cl2—Cu1iii	−80.48 (3)	C1—N2—C8—C9	−48.8 (6)
O1—Cu1—N3—C1	150 (6)	C7—N2—C8—C9	135.3 (4)
Cl1i—Cu1—N3—C1	−4.5 (3)	N3—Cu1—O1—Cu1iii	88 (6)
Cl1—Cu1—N3—C1	116.6 (3)	Cl1i—Cu1—O1—Cu1iii	−117.99 (3)
Cl2—Cu1—N3—C1	−122.7 (3)	Cl1—Cu1—O1—Cu1iii	120.87 (3)
O1—Cu1—N3—C2	−31 (6)	Cl2—Cu1—O1—Cu1iii	0.0
Cl1i—Cu1—N3—C2	174.8 (3)	N3—Cu1—O1—Cu1i	−153 (6)
Cl1—Cu1—N3—C2	−64.1 (3)	Cl1i—Cu1—O1—Cu1i	1.44 (3)
Cl2—Cu1—N3—C2	56.7 (3)	Cl1—Cu1—O1—Cu1i	−119.70 (3)
C2—N3—C1—N2	−0.7 (4)	Cl2—Cu1—O1—Cu1i	119.434 (8)
Cu1—N3—C1—N2	178.8 (2)	N3—Cu1—O1—Cu1ii	−32 (6)
C1—N3—C2—C3	−178.6 (4)	Cl1i—Cu1—O1—Cu1ii	122.58 (3)
Cu1—N3—C2—C3	2.0 (6)	Cl1—Cu1—O1—Cu1ii	1.43 (3)
C1—N3—C2—C7	1.2 (4)	Cl2—Cu1—O1—Cu1ii	−119.434 (8)
Cu1—N3—C2—C7	−178.3 (2)	N2—C8—C9—C10	−102.8 (6)
C3—C2—C7—N2	178.6 (4)	N2—C8—C9—N1	78.9 (5)
N3—C2—C7—N2	−1.2 (4)	N1—C9—C10—C11	1.4 (7)
C3—C2—C7—C6	−2.8 (6)	C8—C9—C10—C11	−176.8 (4)
N3—C2—C7—C6	177.4 (4)	C10—C9—N1—C13	−1.6 (7)
N3—C1—N2—C7	−0.1 (4)	C8—C9—N1—C13	176.8 (5)
N3—C1—N2—C8	−176.6 (4)	C13—C12—C11—C10	−2.7 (10)
C2—C7—N2—C1	0.8 (4)	C9—C10—C11—C12	0.6 (8)
C6—C7—N2—C1	−177.6 (5)	C9—N1—C13—C12	−0.5 (10)
C2—C7—N2—C8	177.4 (4)	C11—C12—C13—N1	2.8 (13)
C6—C7—N2—C8	−1.0 (8)

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