Tetra­kis­(μ-3-meth­oxy­benzoato-κ2O1:O1′)bis[acetonitrilecopper(II)]

Kar, S.; Garai, A.; Bala, S.; Purohit, C.S.

doi:10.1107/S1600536811012074

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 5| May 2011| Page m557

doi:10.1107/S1600536811012074

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Tetrakis(μ-3-methoxybenzoato-κ²O¹:O^1′)bis[acetonitrilecopper(II)]

Sanjib Kar,^a ^* Antara Garai,^a Sukhen Bala ^a and Chandra Shekhar Purohit ^a

^aSchool of Chemical Sciences, National Institute of Science Education and Research, Institute of Physics Campus, PO: Sainik School, Bhubaneswar, Orissa 751 005, India
^*Correspondence e-mail: sanjib@niser.ac.in

(Received 13 March 2011; accepted 31 March 2011; online 7 April 2011)

The centrosymmetric binuclear Cu^II title complex, [Cu₂(C₈H₇O₃)₄(CH₃CN)₂], has a paddle-wheel-type structure [Cu—Cu distance = 2.6433 (3) Å]. Each Cu^II ion is coordinated by four O atoms from two 3-methoxybenzoate ligands and one acetonitrile N atom in a square-pyramidal geometry.

Related literature

For applications of binuclear copper(II) complexes bridged by four benzoic acid groups in a paddle-wheel arrangement in inorganic synthesis, catalysis, magnetism and medicinal chemistry, see: Ozarowski (2008 ); Kirchner & Fernando (1980 ); Inoue et al. (1968 ); Bergant et al. (1994 ). For crystal structures of similar complexes, see: Lah et al. (2001 ). For the preparation of similar complexes, see: Bernard et al. (1989 ).

Experimental

Crystal data

[Cu₂(C₈H₇O₃)₄(C₂H₃N)₂]
M_r = 813.73
Monoclinic, P 2₁ /n
a = 7.2117 (7) Å
b = 19.6502 (3) Å
c = 12.6186 (9) Å
β = 90.016 (9)°
V = 1788.2 (3) Å³
Z = 2
Mo Kα radiation
μ = 1.26 mm⁻¹
T = 293 K
0.25 × 0.22 × 0.08 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.620, T_max = 0.746
43230 measured reflections
6872 independent reflections
4883 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.101
S = 1.01
6872 reflections
238 parameters
H-atom parameters constrained
Δρ_max = 0.40 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SIR92 (Altomare, et al. 1993 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811012074/pk2314sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811012074/pk2314Isup2.hkl

checkCIF report

Comment top

Binuclear copper(II) complexes bridged by four benzoic acid groups in a paddle-wheel arrangement are very important from the perspectives of molecular magnetism (Inoue, et al., 1968). These materials have potential applications in inorganic synthesis, catalysis, magnetism, and in medicinal chemistry (Ozarowski, 2008; Kirchner & Fernando, 1980; Inoue et al., 1968; Bergant et al., 1994). Herein we report the structure of the title compound (Fig.1). The structure is a centrosymmetric dinuclear Cu(II) complex having square pyramidal arrangement around each copper ion. There is a lot of research interest for studying the effect of apical ligand (here the apical ligand is acetonitrile) in tuning the intramolecular magnetic exchange interaction between two Cu(II) ions in various paddle-wheel type dinuclear copper(II) benzoate complexes.

Related literature top

For applications of binuclear copper(II) complexes bridged by four benzoic acid groups in a paddle-wheel arrangement in inorganic synthesis, catalysis, magnetism and medicinal chemistry, see: Ozarowski (2008); Kirchner & Fernando (1980); Inoue et al. (1968); Bergant et al. (1994). For crystal structures of similar complexes, see: Lah et al. (2001). For the preparation of similar complexes, see: Bernard et al. (1989).

Experimental top

The title compound was obtained by addition of the solution of copper(II) acetate monohydrate (0.4 g, 2.0 mmol) in a 1:1 mixture of CH₃CN + CH₃OH (20 ml) to 3-methoxybenzoic acid (1.21 g, 8 mmol), and the mixture was stirred for 2 h. The green precipitate was filtered and washed thoroughly with diethyl ether (1.2 g, 80%). Recrystallization from acetonitrile gave green crystals suitable for X-ray diffraction.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SIR92 (Altomare, et al. 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level. H atoms are shown as small arbitrary spheres. Unlabelled atoms are related to their labelled counterparts by inversion [(x,y,z) to (2-x,2-y,-z)].
	Fig. 2. A packing diagram viewed along the crystallographic a axis.

Tetrakis(µ-3-methoxybenzoato- κ²O¹:O^1')bis[acetonitrilecopper(II)] top

Crystal data top

[Cu₂(C₈H₇O₃)₄(C₂H₃N)₂]	F(000) = 836
M_r = 813.73	D_x = 1.512 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 9972 reflections
a = 7.2117 (7) Å	θ = 2.6–27.4°
b = 19.6502 (3) Å	µ = 1.26 mm⁻¹
c = 12.6186 (9) Å	T = 293 K
β = 90.016 (9)°	Block, green
V = 1788.2 (3) Å³	0.25 × 0.22 × 0.08 mm
Z = 2

Data collection top

Bruker SMART CCD area-detector diffractometer	6872 independent reflections
Radiation source: fine-focus sealed tube	4883 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
ϕ and ω scans	θ_max = 33.5°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −11→10
T_min = 0.620, T_max = 0.746	k = −30→29
43230 measured reflections	l = −18→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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.101	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.0531P)² + 0.2391P] where P = (F_o² + 2F_c²)/3
6872 reflections	(Δ/σ)_max = 0.001
238 parameters	Δρ_max = 0.40 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

[Cu₂(C₈H₇O₃)₄(C₂H₃N)₂]	V = 1788.2 (3) Å³
M_r = 813.73	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.2117 (7) Å	µ = 1.26 mm⁻¹
b = 19.6502 (3) Å	T = 293 K
c = 12.6186 (9) Å	0.25 × 0.22 × 0.08 mm
β = 90.016 (9)°

Data collection top

Bruker SMART CCD area-detector diffractometer	6872 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	4883 reflections with I > 2σ(I)
T_min = 0.620, T_max = 0.746	R_int = 0.036
43230 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.101	H-atom parameters constrained
S = 1.01	Δρ_max = 0.40 e Å⁻³
6872 reflections	Δρ_min = −0.34 e Å⁻³
238 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.

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

	x	y	z	U_iso*/U_eq
Cu1	0.85578 (2)	0.959759 (8)	0.015468 (13)	0.03310 (6)
C1	0.7588 (2)	1.14438 (8)	0.17923 (12)	0.0428 (3)
C2	0.5838 (2)	1.13393 (8)	0.22195 (12)	0.0449 (3)
H2	0.5207	1.0935	0.2093	0.054*
C3	0.5037 (3)	1.18455 (9)	0.28383 (12)	0.0484 (4)
C4	0.5971 (3)	1.24540 (9)	0.30041 (16)	0.0588 (5)
H4	0.5442	1.2790	0.3426	0.071*
C5	0.7672 (3)	1.25604 (9)	0.25470 (16)	0.0626 (5)
H5	0.8271	1.2975	0.2642	0.075*
C6	0.8508 (3)	1.20571 (9)	0.19449 (15)	0.0547 (4)
H6	0.9671	1.2129	0.1646	0.066*
C7	0.8464 (2)	1.08987 (8)	0.11286 (11)	0.0401 (3)
C8	0.2380 (3)	1.11606 (12)	0.32315 (18)	0.0671 (5)
H8A	0.2120	1.1065	0.2500	0.101*
H8B	0.1237	1.1189	0.3619	0.101*
H8C	0.3131	1.0803	0.3521	0.101*
C9	0.7489 (2)	1.07841 (8)	−0.26044 (12)	0.0428 (3)
C10	0.5683 (2)	1.05961 (9)	−0.28718 (12)	0.0461 (4)
H10	0.5042	1.0283	−0.2458	0.055*
C11	0.4845 (3)	1.08807 (10)	−0.37628 (14)	0.0555 (4)
C12	0.5780 (3)	1.13632 (12)	−0.43556 (16)	0.0695 (6)
H12	0.5201	1.1568	−0.4931	0.083*
C13	0.7561 (4)	1.15386 (13)	−0.40930 (17)	0.0787 (7)
H13	0.8192	1.1856	−0.4503	0.094*
C14	0.8439 (3)	1.12486 (10)	−0.32223 (15)	0.0614 (5)
H14	0.9655	1.1366	−0.3057	0.074*
C15	0.8413 (2)	1.04876 (7)	−0.16352 (11)	0.0389 (3)
C16	0.2271 (3)	1.01287 (14)	−0.3747 (2)	0.0789 (7)
H16A	0.3109	0.9755	−0.3852	0.118*
H16B	0.1147	1.0047	−0.4135	0.118*
H16C	0.1991	1.0172	−0.3007	0.118*
C17	0.5228 (3)	0.84701 (10)	0.04591 (16)	0.0570 (4)
C18	0.3797 (3)	0.79457 (13)	0.0586 (2)	0.0804 (7)
H18A	0.3836	0.7770	0.1295	0.121*
H18B	0.4019	0.7583	0.0092	0.121*
H18C	0.2599	0.8141	0.0452	0.121*
N1	0.6281 (2)	0.88878 (8)	0.03641 (12)	0.0559 (4)
O1	0.75919 (17)	1.03482 (5)	0.10169 (10)	0.0476 (3)
O2	1.00189 (17)	1.10313 (6)	0.07340 (10)	0.0503 (3)
O3	0.33498 (19)	1.17917 (7)	0.33120 (11)	0.0611 (3)
O4	0.75562 (16)	1.00329 (6)	−0.11367 (9)	0.0458 (3)
O5	0.99825 (17)	1.07201 (6)	−0.13874 (9)	0.0492 (3)
O6	0.3093 (2)	1.07285 (10)	−0.41088 (13)	0.0801 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.03442 (10)	0.03078 (9)	0.03410 (10)	−0.00225 (6)	−0.00097 (6)	0.00015 (6)
C1	0.0519 (9)	0.0379 (7)	0.0386 (7)	0.0095 (6)	−0.0042 (6)	−0.0037 (6)
C2	0.0551 (10)	0.0401 (7)	0.0394 (7)	0.0106 (7)	−0.0036 (7)	−0.0036 (6)
C3	0.0580 (10)	0.0463 (8)	0.0410 (8)	0.0182 (7)	−0.0024 (7)	−0.0031 (6)
C4	0.0748 (13)	0.0453 (9)	0.0561 (10)	0.0156 (9)	−0.0011 (9)	−0.0123 (7)
C5	0.0797 (14)	0.0404 (9)	0.0677 (12)	0.0021 (9)	−0.0052 (10)	−0.0142 (8)
C6	0.0595 (11)	0.0454 (9)	0.0593 (10)	0.0022 (8)	−0.0016 (8)	−0.0082 (7)
C7	0.0459 (8)	0.0380 (7)	0.0365 (7)	0.0056 (6)	−0.0040 (6)	−0.0017 (5)
C8	0.0561 (12)	0.0765 (14)	0.0687 (12)	0.0080 (10)	0.0022 (9)	−0.0186 (10)
C9	0.0523 (9)	0.0392 (7)	0.0367 (7)	0.0038 (6)	−0.0064 (6)	0.0014 (6)
C10	0.0530 (10)	0.0461 (8)	0.0390 (7)	0.0048 (7)	−0.0053 (7)	0.0040 (6)
C11	0.0599 (11)	0.0621 (11)	0.0444 (8)	0.0071 (8)	−0.0117 (8)	0.0039 (7)
C12	0.0854 (16)	0.0740 (13)	0.0492 (10)	−0.0003 (11)	−0.0182 (10)	0.0206 (9)
C13	0.0931 (17)	0.0831 (15)	0.0598 (12)	−0.0198 (13)	−0.0127 (11)	0.0347 (11)
C14	0.0682 (13)	0.0629 (11)	0.0531 (10)	−0.0130 (9)	−0.0114 (9)	0.0144 (8)
C15	0.0466 (9)	0.0356 (7)	0.0347 (7)	0.0044 (6)	−0.0036 (6)	−0.0012 (5)
C16	0.0613 (14)	0.1005 (19)	0.0749 (15)	−0.0078 (13)	−0.0137 (11)	0.0090 (13)
C17	0.0519 (10)	0.0576 (10)	0.0615 (11)	−0.0063 (8)	−0.0024 (8)	0.0131 (8)
C18	0.0665 (14)	0.0763 (15)	0.0984 (17)	−0.0306 (11)	−0.0125 (12)	0.0349 (13)
N1	0.0525 (9)	0.0597 (9)	0.0553 (9)	−0.0205 (7)	−0.0018 (7)	0.0092 (7)
O1	0.0501 (7)	0.0416 (6)	0.0511 (6)	0.0006 (5)	0.0081 (5)	−0.0104 (5)
O2	0.0510 (7)	0.0418 (6)	0.0581 (7)	−0.0008 (5)	0.0076 (5)	−0.0112 (5)
O3	0.0631 (8)	0.0580 (8)	0.0623 (8)	0.0173 (6)	0.0086 (6)	−0.0118 (6)
O4	0.0477 (6)	0.0489 (6)	0.0408 (5)	−0.0043 (5)	−0.0083 (5)	0.0093 (5)
O5	0.0511 (7)	0.0499 (6)	0.0465 (6)	−0.0077 (5)	−0.0123 (5)	0.0122 (5)
O6	0.0659 (10)	0.1017 (12)	0.0726 (10)	−0.0032 (9)	−0.0282 (8)	0.0271 (9)

Geometric parameters (Å, º) top

Cu1—O2ⁱ	1.9591 (11)	C9—C10	1.395 (2)
Cu1—O1	1.9606 (11)	C9—C15	1.510 (2)
Cu1—O4	1.9769 (11)	C10—C11	1.394 (2)
Cu1—O5ⁱ	1.9791 (11)	C10—H10	0.9300
Cu1—N1	2.1703 (14)	C11—O6	1.369 (2)
Cu1—Cu1ⁱ	2.6416 (3)	C11—C12	1.383 (3)
C1—C2	1.388 (2)	C12—C13	1.370 (3)
C1—C6	1.389 (2)	C12—H12	0.9300
C1—C7	1.499 (2)	C13—C14	1.390 (3)
C2—C3	1.390 (2)	C13—H13	0.9300
C2—H2	0.9300	C14—H14	0.9300
C3—O3	1.360 (2)	C15—O4	1.2554 (19)
C3—C4	1.388 (3)	C15—O5	1.2594 (19)
C4—C5	1.371 (3)	C16—O6	1.396 (3)
C4—H4	0.9300	C16—H16A	0.9600
C5—C6	1.385 (3)	C16—H16B	0.9600
C5—H5	0.9300	C16—H16C	0.9600
C6—H6	0.9300	C17—N1	1.124 (2)
C7—O2	1.254 (2)	C17—C18	1.467 (3)
C7—O1	1.2588 (19)	C18—H18A	0.9600
C8—O3	1.427 (3)	C18—H18B	0.9600
C8—H8A	0.9600	C18—H18C	0.9600
C8—H8B	0.9600	O2—Cu1ⁱ	1.9591 (11)
C8—H8C	0.9600	O5—Cu1ⁱ	1.9791 (11)
C9—C14	1.382 (3)

O2ⁱ—Cu1—O1	168.03 (5)	C14—C9—C10	120.08 (15)
O2ⁱ—Cu1—O4	89.55 (5)	C14—C9—C15	119.54 (15)
O1—Cu1—O4	90.13 (5)	C10—C9—C15	120.38 (14)
O2ⁱ—Cu1—O5ⁱ	88.43 (6)	C11—C10—C9	119.58 (17)
O1—Cu1—O5ⁱ	89.42 (5)	C11—C10—H10	120.2
O4—Cu1—O5ⁱ	168.11 (5)	C9—C10—H10	120.2
O2ⁱ—Cu1—N1	93.49 (6)	O6—C11—C12	115.27 (16)
O1—Cu1—N1	98.44 (6)	O6—C11—C10	124.71 (18)
O4—Cu1—N1	95.86 (5)	C12—C11—C10	120.00 (18)
O5ⁱ—Cu1—N1	95.96 (5)	C13—C12—C11	119.90 (17)
O2ⁱ—Cu1—Cu1ⁱ	83.13 (4)	C13—C12—H12	120.0
O1—Cu1—Cu1ⁱ	84.93 (4)	C11—C12—H12	120.0
O4—Cu1—Cu1ⁱ	84.64 (3)	C12—C13—C14	120.98 (19)
O5ⁱ—Cu1—Cu1ⁱ	83.48 (4)	C12—C13—H13	119.5
N1—Cu1—Cu1ⁱ	176.58 (5)	C14—C13—H13	119.5
C2—C1—C6	120.59 (15)	C9—C14—C13	119.39 (19)
C2—C1—C7	119.64 (14)	C9—C14—H14	120.3
C6—C1—C7	119.74 (16)	C13—C14—H14	120.3
C1—C2—C3	119.36 (16)	O4—C15—O5	125.17 (14)
C1—C2—H2	120.3	O4—C15—C9	117.60 (14)
C3—C2—H2	120.3	O5—C15—C9	117.23 (13)
O3—C3—C4	115.76 (15)	O6—C16—H16A	109.5
O3—C3—C2	124.28 (17)	O6—C16—H16B	109.5
C4—C3—C2	119.96 (18)	H16A—C16—H16B	109.5
C5—C4—C3	120.11 (16)	O6—C16—H16C	109.5
C5—C4—H4	119.9	H16A—C16—H16C	109.5
C3—C4—H4	119.9	H16B—C16—H16C	109.5
C4—C5—C6	120.75 (18)	N1—C17—C18	177.7 (2)
C4—C5—H5	119.6	C17—C18—H18A	109.5
C6—C5—H5	119.6	C17—C18—H18B	109.5
C5—C6—C1	119.18 (19)	H18A—C18—H18B	109.5
C5—C6—H6	120.4	C17—C18—H18C	109.5
C1—C6—H6	120.4	H18A—C18—H18C	109.5
O2—C7—O1	125.48 (14)	H18B—C18—H18C	109.5
O2—C7—C1	116.75 (14)	C17—N1—Cu1	173.08 (18)
O1—C7—C1	117.77 (15)	C7—O1—Cu1	122.06 (11)
O3—C8—H8A	109.5	C7—O2—Cu1ⁱ	124.38 (10)
O3—C8—H8B	109.5	C3—O3—C8	118.32 (14)
H8A—C8—H8B	109.5	C15—O4—Cu1	122.76 (10)
O3—C8—H8C	109.5	C15—O5—Cu1ⁱ	123.93 (10)
H8A—C8—H8C	109.5	C11—O6—C16	118.17 (16)
H8B—C8—H8C	109.5

Symmetry code: (i) −x+2, −y+2, −z.

Experimental details

Crystal data
Chemical formula	[Cu₂(C₈H₇O₃)₄(C₂H₃N)₂]
M_r	813.73
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	7.2117 (7), 19.6502 (3), 12.6186 (9)
β (°)	90.016 (9)
V (Å³)	1788.2 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.26
Crystal size (mm)	0.25 × 0.22 × 0.08

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.620, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	43230, 6872, 4883
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.777

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.101, 1.01
No. of reflections	6872
No. of parameters	238
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.40, −0.34

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SIR92 (Altomare, et al. 1993), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999), publCIF (Westrip, 2010).

Acknowledgements

Financial support received from the Department of Atomic Energy (India) is gratefully acknowledged. The X-ray structural studies were carried out at the National Institute of Science Education and Research, Bhubaneswar, India.

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