Tetra-μ-benzoato-bis-[(quinoxaline)copper(II)].

The paddlewheel-type centrosymmetric dinuclear title complex, [Cu(2)(C(7)H(5)O(2))(4)(C(8)H(6)N(2))(2)], contains four bridging benzoate groups and two terminal quinoxaline ligands. The octa-hedral coordination around each Cu atom, with four O atoms in the equatorial plane, is completed by an N atom of a quinoxaline mol-ecule [Cu-N = 2.2465 (18) Å] and by the second Cu atom [Cu⋯Cu = 2.668 (5) Å]. The Cu atom is 0.216 Å out of the plane of the four O atoms.

Related literature

For the related structure, Cu2(O2CPh)4(py)2 (py = pyridine), see: Speier & Fülöp (1989 ▶). For background information, see: Cotton & Walton (1993 ▶); Pichon et al. (2007 ▶); Goto et al. (2007 ▶); Takamizawa et al. (2004 ▶); Casarin et al. (2005 ▶); Deka et al. (2006 ▶).

Experimental

Crystal data

[Cu2(C7H5O2)4(C8H6N2)2]

M = 871.82

Triclinic,

a = 10.1423 (16) Å

b = 10.3400 (17) Å

c = 10.5148 (17) Å

α = 65.459 (2)°

β = 73.063 (3)°

γ = 82.142 (3)°

V = 959.4 (3) Å3

Z = 1

Mo Kα radiation

μ = 1.17 mm−1

T = 293 (2) K

0.15 × 0.10 × 0.08 mm

Data collection

Bruker SMART CCD area-detector diffractometer

Absorption correction: none

5377 measured reflections

3668 independent reflections

2983 reflections with I > 2σ(I)

R int = 0.031

Refinement

R[F 2 > 2σ(F 2)] = 0.033

wR(F 2) = 0.080

S = 0.96

3668 reflections

262 parameters

H-atom parameters constrained

Δρmax = 0.28 e Å−3

Δρmin = −0.41 e Å−3

Data collection: SMART (Bruker, 1997 ▶); cell refinement: SAINT (Bruker, 1997 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997 ▶); molecular graphics: SHELXTL (Bruker, 1998 ▶); software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536807067876/dn2301sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536807067876/dn2301Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

[Cu2(C7H5O2)4(C8H6N2)2]	Z = 1
Mr = 871.82	F000 = 446
Triclinic, P1	Dx = 1.509 Mg m−3
Hall symbol: -P 1	Mo Kα radiation λ = 0.71073 Å
a = 10.1423 (16) Å	Cell parameters from 2414 reflections
b = 10.3400 (17) Å	θ = 2.4–27.2º
c = 10.5148 (17) Å	µ = 1.17 mm−1
α = 65.459 (2)º	T = 293 (2) K
β = 73.063 (3)º	Block, blue
γ = 82.142 (3)º	0.15 × 0.10 × 0.08 mm
V = 959.4 (3) Å3

Bruker SMART CCD area-detector diffractometer	2983 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.031
Monochromator: graphite	θmax = 26.0º
T = 293(2) K	θmin = 2.1º
φ and ω scans	h = −6→12
Absorption correction: none	k = −12→12
5377 measured reflections	l = −11→12
3668 independent reflections

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)] = 0.033	H-atom parameters constrained
wR(F2) = 0.080	w = 1/[σ2(Fo2) + (0.0403P)2] where P = (Fo2 + 2Fc2)/3
S = 0.96	(Δ/σ)max = 0.002
3668 reflections	Δρmax = 0.28 e Å−3
262 parameters	Δρmin = −0.41 e Å−3
Primary atom site location: structure-invariant direct methods	Extinction correction: none

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.

	x	y	z	Uiso*/Ueq
Cu1	1.11111 (3)	0.47628 (3)	0.40624 (3)	0.03419 (11)
O11	0.99508 (16)	0.32526 (17)	0.43180 (19)	0.0499 (5)
O12	1.18983 (16)	0.63828 (16)	0.40754 (17)	0.0440 (4)
C11	0.8752 (2)	0.2967 (2)	0.5137 (2)	0.0369 (5)
C12	0.8048 (2)	0.1757 (2)	0.5189 (2)	0.0351 (5)
C13	0.8728 (3)	0.0988 (3)	0.4383 (3)	0.0492 (6)
H13	0.9618	0.1230	0.3800	0.059*
C14	0.8095 (3)	−0.0143 (3)	0.4433 (3)	0.0568 (7)
H14	0.8564	−0.0666	0.3897	0.068*
C15	0.6776 (3)	−0.0490 (3)	0.5274 (3)	0.0498 (7)
H15	0.6349	−0.1247	0.5306	0.060*
C16	0.6087 (3)	0.0279 (3)	0.6069 (3)	0.0470 (6)
H16	0.5191	0.0044	0.6637	0.056*
C17	0.6716 (2)	0.1398 (2)	0.6030 (2)	0.0408 (6)
H17	0.6243	0.1916	0.6572	0.049*
O21	1.02164 (17)	0.60977 (18)	0.25640 (18)	0.0495 (4)
O22	1.16461 (17)	0.35143 (16)	0.58557 (17)	0.0452 (4)
C21	0.9089 (2)	0.6714 (2)	0.2873 (2)	0.0370 (5)
C22	0.8591 (2)	0.7841 (2)	0.1645 (2)	0.0382 (5)
C23	0.7344 (3)	0.8541 (3)	0.1901 (3)	0.0535 (7)
H23	0.6771	0.8249	0.2837	0.064*
C24	0.6936 (3)	0.9660 (3)	0.0797 (3)	0.0694 (9)
H24	0.6096	1.0123	0.0993	0.083*
C25	0.7761 (4)	1.0094 (3)	−0.0586 (3)	0.0678 (9)
H25	0.7497	1.0866	−0.1329	0.081*
C26	0.8975 (3)	0.9385 (3)	−0.0869 (3)	0.0666 (8)
H26	0.9523	0.9660	−0.1815	0.080*
C27	0.9401 (3)	0.8263 (3)	0.0233 (3)	0.0540 (7)
H27	1.0232	0.7791	0.0026	0.065*
N31	1.28562 (19)	0.41356 (19)	0.25284 (19)	0.0354 (4)
N32	1.4763 (2)	0.2919 (2)	0.0746 (2)	0.0522 (6)
C31	1.2485 (3)	0.3591 (3)	0.1760 (3)	0.0457 (6)
H31	1.1554	0.3601	0.1804	0.055*
C32	1.3443 (3)	0.2991 (3)	0.0868 (3)	0.0519 (7)
H32	1.3115	0.2631	0.0344	0.062*
C33	1.5184 (2)	0.3494 (2)	0.1517 (3)	0.0443 (6)
C34	1.6606 (3)	0.3475 (3)	0.1428 (3)	0.0615 (8)
H34	1.7237	0.3059	0.0862	0.074*
C35	1.7047 (3)	0.4059 (3)	0.2163 (3)	0.0684 (9)
H35	1.7984	0.4048	0.2089	0.082*
C36	1.6121 (3)	0.4678 (3)	0.3030 (3)	0.0608 (8)
H36	1.6448	0.5078	0.3523	0.073*
C37	1.4736 (3)	0.4702 (3)	0.3163 (3)	0.0468 (6)
H37	1.4124	0.5106	0.3753	0.056*
C38	1.4240 (2)	0.4112 (2)	0.2406 (2)	0.0363 (5)

	U11	U22	U33	U12	U13	U23
Cu1	0.03083 (17)	0.03639 (17)	0.04054 (18)	−0.00078 (11)	−0.00605 (12)	−0.02234 (13)
O11	0.0379 (10)	0.0541 (11)	0.0676 (12)	−0.0115 (8)	0.0016 (9)	−0.0407 (9)
O12	0.0422 (10)	0.0443 (10)	0.0528 (10)	−0.0082 (8)	−0.0025 (8)	−0.0307 (8)
C11	0.0375 (14)	0.0357 (13)	0.0414 (13)	−0.0001 (11)	−0.0138 (12)	−0.0168 (11)
C12	0.0380 (13)	0.0327 (12)	0.0396 (13)	−0.0006 (10)	−0.0150 (11)	−0.0159 (10)
C13	0.0387 (14)	0.0505 (15)	0.0651 (17)	−0.0080 (12)	−0.0026 (13)	−0.0344 (14)
C14	0.0577 (18)	0.0534 (17)	0.0745 (19)	−0.0017 (14)	−0.0120 (15)	−0.0430 (15)
C15	0.0589 (18)	0.0380 (14)	0.0593 (16)	−0.0103 (12)	−0.0237 (14)	−0.0174 (12)
C16	0.0423 (15)	0.0473 (15)	0.0485 (15)	−0.0119 (12)	−0.0099 (12)	−0.0141 (12)
C17	0.0433 (14)	0.0411 (14)	0.0403 (13)	−0.0041 (11)	−0.0112 (11)	−0.0172 (11)
O21	0.0420 (10)	0.0636 (11)	0.0481 (10)	0.0139 (9)	−0.0157 (8)	−0.0291 (9)
O22	0.0435 (10)	0.0467 (10)	0.0421 (10)	0.0063 (8)	−0.0103 (8)	−0.0171 (8)
C21	0.0380 (14)	0.0378 (13)	0.0463 (14)	−0.0037 (11)	−0.0137 (12)	−0.0246 (11)
C22	0.0433 (14)	0.0392 (13)	0.0408 (13)	−0.0027 (11)	−0.0134 (11)	−0.0220 (11)
C23	0.0600 (18)	0.0604 (17)	0.0413 (14)	0.0139 (14)	−0.0151 (13)	−0.0246 (13)
C24	0.089 (2)	0.067 (2)	0.0587 (19)	0.0328 (18)	−0.0347 (18)	−0.0315 (16)
C25	0.100 (3)	0.0545 (18)	0.0569 (19)	0.0055 (18)	−0.0405 (19)	−0.0190 (15)
C26	0.081 (2)	0.076 (2)	0.0396 (16)	−0.0212 (18)	−0.0102 (16)	−0.0173 (15)
C27	0.0476 (16)	0.0667 (19)	0.0508 (16)	−0.0041 (14)	−0.0096 (14)	−0.0275 (14)
N31	0.0364 (11)	0.0353 (10)	0.0357 (10)	−0.0006 (8)	−0.0072 (9)	−0.0169 (9)
N32	0.0573 (15)	0.0457 (13)	0.0505 (13)	0.0041 (11)	−0.0010 (11)	−0.0263 (11)
C31	0.0421 (15)	0.0506 (15)	0.0452 (14)	−0.0046 (12)	−0.0048 (12)	−0.0230 (12)
C32	0.0621 (19)	0.0520 (16)	0.0474 (15)	−0.0075 (14)	−0.0044 (14)	−0.0299 (13)
C33	0.0401 (14)	0.0364 (13)	0.0419 (14)	0.0056 (11)	−0.0030 (12)	−0.0084 (11)
C34	0.0439 (16)	0.0628 (19)	0.0628 (19)	0.0138 (14)	−0.0055 (15)	−0.0205 (15)
C35	0.0355 (16)	0.084 (2)	0.065 (2)	0.0011 (15)	−0.0125 (15)	−0.0107 (17)
C36	0.0482 (17)	0.078 (2)	0.0540 (17)	−0.0079 (15)	−0.0188 (15)	−0.0183 (15)
C37	0.0422 (15)	0.0528 (16)	0.0447 (14)	−0.0024 (12)	−0.0100 (12)	−0.0189 (12)
C38	0.0356 (13)	0.0332 (12)	0.0331 (12)	0.0000 (10)	−0.0055 (10)	−0.0089 (10)

Cu1—O12	1.9582 (15)	C23—C24	1.375 (3)
Cu1—O11	1.9660 (15)	C23—H23	0.9300
Cu1—O21	1.9735 (16)	C24—C25	1.367 (4)
Cu1—O22	1.9746 (16)	C24—H24	0.9300
Cu1—N31	2.2465 (18)	C25—C26	1.366 (4)
Cu1—Cu1i	2.6683 (6)	C25—H25	0.9300
O11—C11	1.258 (3)	C26—C27	1.383 (4)
O12—C11i	1.263 (2)	C26—H26	0.9300
C11—O12i	1.263 (2)	C27—H27	0.9300
C11—C12	1.498 (3)	N31—C31	1.313 (3)
C12—C13	1.377 (3)	N31—C38	1.370 (3)
C12—C17	1.383 (3)	N32—C32	1.302 (3)
C13—C14	1.383 (3)	N32—C33	1.366 (3)
C13—H13	0.9300	C31—C32	1.413 (3)
C14—C15	1.370 (4)	C31—H31	0.9300
C14—H14	0.9300	C32—H32	0.9300
C15—C16	1.371 (3)	C33—C34	1.415 (4)
C15—H15	0.9300	C33—C38	1.416 (3)
C16—C17	1.376 (3)	C34—C35	1.351 (4)
C16—H16	0.9300	C34—H34	0.9300
C17—H17	0.9300	C35—C36	1.395 (4)
O21—C21	1.255 (3)	C35—H35	0.9300
O22—C21i	1.267 (3)	C36—C37	1.369 (3)
C21—O22i	1.267 (3)	C36—H36	0.9300
C21—C22	1.500 (3)	C37—C38	1.407 (3)
C22—C23	1.381 (3)	C37—H37	0.9300
C22—C27	1.386 (3)
O12—Cu1—O11	167.30 (6)	C27—C22—C21	120.9 (2)
O12—Cu1—O21	89.25 (7)	C24—C23—C22	121.2 (3)
O11—Cu1—O21	88.44 (7)	C24—C23—H23	119.4
O12—Cu1—O22	89.63 (7)	C22—C23—H23	119.4
O11—Cu1—O22	89.93 (7)	C25—C24—C23	120.2 (3)
O21—Cu1—O22	167.48 (6)	C25—C24—H24	119.9
O12—Cu1—N31	101.20 (7)	C23—C24—H24	119.9
O11—Cu1—N31	91.45 (6)	C26—C25—C24	119.5 (3)
O21—Cu1—N31	95.59 (7)	C26—C25—H25	120.3
O22—Cu1—N31	96.86 (7)	C24—C25—H25	120.3
O12—Cu1—Cu1i	85.49 (5)	C25—C26—C27	120.9 (3)
O11—Cu1—Cu1i	81.87 (5)	C25—C26—H26	119.6
O21—Cu1—Cu1i	85.08 (5)	C27—C26—H26	119.6
O22—Cu1—Cu1i	82.40 (5)	C26—C27—C22	120.0 (3)
N31—Cu1—Cu1i	173.27 (5)	C26—C27—H27	120.0
C11—O11—Cu1	125.83 (15)	C22—C27—H27	120.0
C11i—O12—Cu1	121.79 (15)	C31—N31—C38	116.26 (19)
O11—C11—O12i	125.0 (2)	C31—N31—Cu1	115.16 (15)
O11—C11—C12	117.4 (2)	C38—N31—Cu1	128.20 (14)
O12i—C11—C12	117.6 (2)	C32—N32—C33	115.7 (2)
C13—C12—C17	119.0 (2)	N31—C31—C32	122.6 (2)
C13—C12—C11	119.8 (2)	N31—C31—H31	118.7
C17—C12—C11	121.1 (2)	C32—C31—H31	118.7
C12—C13—C14	120.4 (2)	N32—C32—C31	123.1 (2)
C12—C13—H13	119.8	N32—C32—H32	118.5
C14—C13—H13	119.8	C31—C32—H32	118.5
C15—C14—C13	120.0 (2)	N32—C33—C34	119.2 (2)
C15—C14—H14	120.0	N32—C33—C38	122.0 (2)
C13—C14—H14	120.0	C34—C33—C38	118.9 (2)
C14—C15—C16	120.0 (2)	C35—C34—C33	120.1 (3)
C14—C15—H15	120.0	C35—C34—H34	119.9
C16—C15—H15	120.0	C33—C34—H34	119.9
C15—C16—C17	120.3 (2)	C34—C35—C36	121.1 (3)
C15—C16—H16	119.9	C34—C35—H35	119.4
C17—C16—H16	119.9	C36—C35—H35	119.4
C16—C17—C12	120.3 (2)	C37—C36—C35	120.6 (3)
C16—C17—H17	119.8	C37—C36—H36	119.7
C12—C17—H17	119.8	C35—C36—H36	119.7
C21—O21—Cu1	122.18 (16)	C36—C37—C38	119.8 (2)
C21i—O22—Cu1	125.03 (15)	C36—C37—H37	120.1
O21—C21—O22i	125.1 (2)	C38—C37—H37	120.1
O21—C21—C22	117.6 (2)	N31—C38—C37	120.2 (2)
O22i—C21—C22	117.2 (2)	N31—C38—C33	120.3 (2)
C23—C22—C27	118.2 (2)	C37—C38—C33	119.4 (2)
C23—C22—C21	120.8 (2)