Tetra-μ-acetato-κ8O:O′-bis[(N2,N2-di­methyl­pyrazin-2-amine-κN4)copper(II)]

Meng, L.; Yang, L.Y.; Shi, J.M.

doi:10.1107/S160053680901719X

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 6| June 2009| Page m646

doi:10.1107/S160053680901719X

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Tetra-μ-acetato-κ⁸O:O′-bis[(N²,N²-dimethylpyrazin-2-amine-κN⁴)copper(II)]

Lin Meng,^a Lin Yan Yang ^a and Jing Min Shi ^a ^*

^aDepartment of Chemistry, Shandong Normal University, Jinan 250014, People's Republic of China
^*Correspondence e-mail: shijingmin1955@yahoo.com.cn

(Received 19 April 2009; accepted 7 May 2009; online 14 May 2009)

The title binuclear complex, [Cu₂(C₂H₃O₂)₄(C₆H₉N₃)₂], lies on an inversion center with four acetate ligands bridging two Cu^II ions and two monodentate N,N-dimethylpyrazine-2-amine ligands coordinating each Cu^II ion via N atoms, forming slightly distorted square-pyramidal environments.

Related literature

For related structures, see: Zhang et al. (2007 ); Li et al. (2003 ).

Experimental

Crystal data

[Cu₂(C₂H₃O₂)₄(C₆H₉N₃)₂]
M_r = 609.58
Triclinic, $[P \overline 1]$
a = 8.1052 (13) Å
b = 8.1775 (13) Å
c = 10.6534 (17) Å
α = 67.826 (2)°
β = 80.013 (2)°
γ = 87.328 (2)°
V = 643.84 (18) Å³
Z = 1
Mo Kα radiation
μ = 1.71 mm⁻¹
T = 298 K
0.68 × 0.41 × 0.31 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.390, T_max = 0.620
3494 measured reflections
2465 independent reflections
2317 reflections with I > 2σ(I)
R_int = 0.016

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.094
S = 1.09
2465 reflections
167 parameters
H-atom parameters constrained
Δρ_max = 0.54 e Å⁻³
Δρ_min = −0.44 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Cu1—O3	1.9649 (18)
Cu1—O1	1.9654 (19)
Cu1—O2	1.9738 (18)
Cu1—O4	1.9756 (18)
Cu1—N1	2.197 (2)

O3—Cu1—O1	168.16 (8)
O3—Cu1—O2	89.93 (9)
O1—Cu1—O2	90.44 (9)
O3—Cu1—O4	88.93 (8)
O1—Cu1—O4	88.32 (9)
O2—Cu1—O4	168.35 (7)
O3—Cu1—N1	94.74 (8)
O1—Cu1—N1	97.07 (8)
O2—Cu1—N1	92.23 (8)
O4—Cu1—N1	99.42 (8)

Data collection: SMART (Bruker, 1997 ); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680901719X/lh2807sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680901719X/lh2807Isup2.hkl

checkCIF report

Comment top

Both acetate anions and pyrazine derivatives are useful ligands and a large number of multi-atom complexes have been synthesized with these as bridging ligands (Zhang et al., 2007; Li et al., 2003). We attempted to synthesize a mixed bridged multi-nuclear Cu^II complex by using acetate and N,N-dimethylpyrazine-2-amine as bridging ligands. The title complex was obtained and here we report its crystal structure, (I), Fig. 1.

The unique Cu^II ion is in a slightly distorted square-pyramidal coordination geometry with atom N1 lying at the apex. Four acetate ligands coordinate to two symmetry-related Cu^II atoms, with a Cu1···Cu1ⁱ separation of 2.6326 (6) Å and inversion centre lies at the middle of the Cu1···Cu1ⁱ vector (symmetry code, (i): -x + 1, -y + 1, -z + 2) resulting in the formation of a binuclear complex. The title complex is similar to a reported binuclear Cu^II complex (Zhang et al., 2007) except the title complex exhibits a slightly shorter Cu—N bond and a slightly longer Cu—Cu distance.

Related literature top

For related structures, see: Zhang et al. (2007); Li et al. (2003).

Experimental top

N,N-dimethylpyrazine-2-amine (0.0954 g, 0.0696 mmol) was dissolved in 10 ml methanol and it was added into 10 ml water solution containing copper acetate (0.1390 g, 0.696 mmol), and the mixed solution was stirred for a few minutes. The blue single crystals were obtained after the solution had been allowed to stand at room temperature for five months.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Primed atoms are related by the symmetry operator (-x + 1, -y + 1, -z + 2).

Tetra-µ-acetato-κ⁸O:O'-bis[(N²,N²- dimethylpyrazin-2-amine-κN⁴)copper(II)] top

Crystal data top

[Cu₂(C₂H₃O₂)₄(C₆H₉N₃)₂]	Z = 1
M_r = 609.58	F(000) = 314
Triclinic, P1	D_x = 1.572 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.1052 (13) Å	Cell parameters from 2730 reflections
b = 8.1775 (13) Å	θ = 2.7–28.2°
c = 10.6534 (17) Å	µ = 1.71 mm⁻¹
α = 67.826 (2)°	T = 298 K
β = 80.013 (2)°	Block, blue
γ = 87.328 (2)°	0.68 × 0.41 × 0.31 mm
V = 643.84 (18) Å³

Data collection top

Bruker SMART APEX CCD diffractometer	2465 independent reflections
Radiation source: fine-focus sealed tube	2317 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.016
ϕ and ω scans	θ_max = 26.0°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→8
T_min = 0.390, T_max = 0.620	k = −10→8
3494 measured reflections	l = −12→13

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)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.094	H-atom parameters constrained
S = 1.09	w = 1/[σ²(F_o²) + (0.0576P)² + 0.297P] where P = (F_o² + 2F_c²)/3
2465 reflections	(Δ/σ)_max = 0.020
167 parameters	Δρ_max = 0.54 e Å⁻³
0 restraints	Δρ_min = −0.44 e Å⁻³

Crystal data top

[Cu₂(C₂H₃O₂)₄(C₆H₉N₃)₂]	γ = 87.328 (2)°
M_r = 609.58	V = 643.84 (18) Å³
Triclinic, P1	Z = 1
a = 8.1052 (13) Å	Mo Kα radiation
b = 8.1775 (13) Å	µ = 1.71 mm⁻¹
c = 10.6534 (17) Å	T = 298 K
α = 67.826 (2)°	0.68 × 0.41 × 0.31 mm
β = 80.013 (2)°

Data collection top

Bruker SMART APEX CCD diffractometer	2465 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2317 reflections with I > 2σ(I)
T_min = 0.390, T_max = 0.620	R_int = 0.016
3494 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	0 restraints
wR(F²) = 0.094	H-atom parameters constrained
S = 1.09	Δρ_max = 0.54 e Å⁻³
2465 reflections	Δρ_min = −0.44 e Å⁻³
167 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
C1	0.2373 (3)	0.6709 (3)	0.9386 (3)	0.0309 (5)
C2	0.0727 (3)	0.7590 (4)	0.9109 (3)	0.0471 (7)
H2A	0.0903	0.8578	0.8247	0.071*
H2B	0.0273	0.7995	0.9832	0.071*
H2C	−0.0043	0.6759	0.9072	0.071*
C3	0.6075 (3)	0.7439 (3)	1.0579 (3)	0.0362 (6)
C4	0.6713 (4)	0.8898 (4)	1.0918 (4)	0.0531 (8)
H4A	0.7270	0.9792	1.0090	0.080*
H4B	0.7487	0.8427	1.1548	0.080*
H4C	0.5788	0.9406	1.1330	0.080*
C5	0.6480 (4)	0.8180 (4)	0.5613 (3)	0.0480 (7)
H5	0.5351	0.8437	0.5768	0.058*
C6	0.7422 (4)	0.9016 (4)	0.4350 (3)	0.0577 (9)
H6	0.6911	0.9856	0.3675	0.069*
C7	0.8757 (3)	0.6637 (4)	0.6357 (3)	0.0367 (6)
H7	0.9256	0.5812	0.7048	0.044*
C8	0.9720 (3)	0.7479 (4)	0.5042 (3)	0.0413 (6)
C9	1.2305 (5)	0.8021 (6)	0.3383 (4)	0.0780 (12)
H9A	1.1700	0.7980	0.2696	0.117*
H9B	1.3370	0.7474	0.3294	0.117*
H9C	1.2478	0.9229	0.3261	0.117*
C10	1.2205 (4)	0.5823 (6)	0.5770 (4)	0.0647 (9)
H10A	1.2374	0.6312	0.6430	0.097*
H10B	1.3270	0.5564	0.5338	0.097*
H10C	1.1538	0.4757	0.6228	0.097*
Cu1	0.57009 (3)	0.57928 (4)	0.87055 (3)	0.02811 (13)
N1	0.7160 (3)	0.6997 (3)	0.6627 (2)	0.0350 (5)
N2	0.9033 (4)	0.8693 (4)	0.4033 (3)	0.0548 (7)
N3	1.1350 (3)	0.7085 (4)	0.4739 (3)	0.0577 (7)
O1	0.4726 (3)	0.3816 (3)	0.8439 (2)	0.0446 (5)
O2	0.7587 (2)	0.4311 (3)	0.94000 (19)	0.0408 (4)
O3	0.6383 (2)	0.7576 (3)	0.9348 (2)	0.0411 (4)
O4	0.3574 (2)	0.7044 (2)	0.83984 (19)	0.0379 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0290 (12)	0.0292 (11)	0.0330 (13)	−0.0015 (9)	−0.0048 (10)	−0.0099 (10)
C2	0.0300 (13)	0.0478 (16)	0.0536 (18)	0.0026 (11)	−0.0087 (12)	−0.0076 (13)
C3	0.0276 (12)	0.0386 (14)	0.0479 (16)	0.0033 (10)	−0.0077 (11)	−0.0221 (12)
C4	0.0561 (18)	0.0498 (17)	0.063 (2)	−0.0056 (14)	−0.0098 (15)	−0.0309 (15)
C5	0.0421 (15)	0.0538 (17)	0.0360 (15)	0.0115 (13)	0.0022 (12)	−0.0083 (13)
C6	0.064 (2)	0.0578 (19)	0.0297 (15)	0.0184 (16)	0.0014 (14)	0.0023 (13)
C7	0.0354 (13)	0.0425 (14)	0.0271 (12)	−0.0005 (11)	0.0007 (10)	−0.0099 (11)
C8	0.0405 (14)	0.0440 (15)	0.0341 (14)	−0.0037 (11)	0.0065 (11)	−0.0139 (12)
C9	0.061 (2)	0.088 (3)	0.065 (2)	−0.010 (2)	0.0353 (19)	−0.024 (2)
C10	0.0394 (17)	0.088 (3)	0.072 (2)	0.0077 (16)	−0.0050 (16)	−0.039 (2)
Cu1	0.02545 (18)	0.03205 (19)	0.02278 (18)	−0.00127 (12)	0.00141 (12)	−0.00789 (13)
N1	0.0349 (11)	0.0380 (11)	0.0270 (11)	−0.0005 (9)	0.0026 (9)	−0.0096 (9)
N2	0.0591 (16)	0.0529 (15)	0.0328 (13)	0.0057 (12)	0.0109 (12)	−0.0028 (11)
N3	0.0402 (14)	0.0682 (18)	0.0511 (16)	0.0005 (12)	0.0134 (12)	−0.0163 (14)
O1	0.0521 (12)	0.0447 (11)	0.0411 (11)	−0.0074 (9)	−0.0005 (9)	−0.0228 (9)
O2	0.0323 (9)	0.0473 (11)	0.0312 (10)	0.0073 (8)	0.0004 (7)	−0.0048 (8)
O3	0.0438 (10)	0.0409 (10)	0.0390 (10)	−0.0095 (8)	−0.0003 (8)	−0.0169 (8)
O4	0.0307 (9)	0.0441 (10)	0.0313 (9)	0.0039 (7)	−0.0032 (7)	−0.0070 (8)

Geometric parameters (Å, º) top

C1—O2ⁱ	1.252 (3)	C7—H7	0.9300
C1—O4	1.258 (3)	C8—N2	1.342 (4)
C1—C2	1.507 (3)	C8—N3	1.358 (4)
C2—H2A	0.9600	C9—N3	1.451 (4)
C2—H2B	0.9600	C9—H9A	0.9600
C2—H2C	0.9600	C9—H9B	0.9600
C3—O3	1.255 (3)	C9—H9C	0.9600
C3—O1ⁱ	1.259 (3)	C10—N3	1.447 (5)
C3—C4	1.506 (4)	C10—H10A	0.9600
C4—H4A	0.9600	C10—H10B	0.9600
C4—H4B	0.9600	C10—H10C	0.9600
C4—H4C	0.9600	Cu1—O3	1.9649 (18)
C5—N1	1.331 (4)	Cu1—O1	1.9654 (19)
C5—C6	1.363 (4)	Cu1—O2	1.9738 (18)
C5—H5	0.9300	Cu1—O4	1.9756 (18)
C6—N2	1.331 (4)	Cu1—N1	2.197 (2)
C6—H6	0.9300	Cu1—Cu1ⁱ	2.6326 (6)
C7—N1	1.321 (3)	O1—C3ⁱ	1.259 (3)
C7—C8	1.411 (4)	O2—C1ⁱ	1.252 (3)

O2ⁱ—C1—O4	125.7 (2)	H9A—C9—H9C	109.5
O2ⁱ—C1—C2	116.0 (2)	H9B—C9—H9C	109.5
O4—C1—C2	118.3 (2)	N3—C10—H10A	109.5
C1—C2—H2A	109.5	N3—C10—H10B	109.5
C1—C2—H2B	109.5	H10A—C10—H10B	109.5
H2A—C2—H2B	109.5	N3—C10—H10C	109.5
C1—C2—H2C	109.5	H10A—C10—H10C	109.5
H2A—C2—H2C	109.5	H10B—C10—H10C	109.5
H2B—C2—H2C	109.5	O3—Cu1—O1	168.16 (8)
O3—C3—O1ⁱ	125.6 (2)	O3—Cu1—O2	89.93 (9)
O3—C3—C4	117.4 (3)	O1—Cu1—O2	90.44 (9)
O1ⁱ—C3—C4	117.0 (2)	O3—Cu1—O4	88.93 (8)
C3—C4—H4A	109.5	O1—Cu1—O4	88.32 (9)
C3—C4—H4B	109.5	O2—Cu1—O4	168.35 (7)
H4A—C4—H4B	109.5	O3—Cu1—N1	94.74 (8)
C3—C4—H4C	109.5	O1—Cu1—N1	97.07 (8)
H4A—C4—H4C	109.5	O2—Cu1—N1	92.23 (8)
H4B—C4—H4C	109.5	O4—Cu1—N1	99.42 (8)
N1—C5—C6	120.7 (3)	O3—Cu1—Cu1ⁱ	83.66 (6)
N1—C5—H5	119.7	O1—Cu1—Cu1ⁱ	84.71 (6)
C6—C5—H5	119.7	O2—Cu1—Cu1ⁱ	81.05 (6)
N2—C6—C5	123.5 (3)	O4—Cu1—Cu1ⁱ	87.31 (5)
N2—C6—H6	118.3	N1—Cu1—Cu1ⁱ	173.08 (6)
C5—C6—H6	118.3	C7—N1—C5	117.8 (2)
N1—C7—C8	121.3 (3)	C7—N1—Cu1	121.20 (18)
N1—C7—H7	119.3	C5—N1—Cu1	120.88 (18)
C8—C7—H7	119.3	C6—N2—C8	116.2 (2)
N2—C8—N3	117.6 (3)	C8—N3—C10	121.5 (3)
N2—C8—C7	120.4 (3)	C8—N3—C9	120.0 (3)
N3—C8—C7	122.0 (3)	C10—N3—C9	118.4 (3)
N3—C9—H9A	109.5	C3ⁱ—O1—Cu1	122.29 (17)
N3—C9—H9B	109.5	C1ⁱ—O2—Cu1	126.74 (17)
H9A—C9—H9B	109.5	C3—O3—Cu1	123.65 (17)
N3—C9—H9C	109.5	C1—O4—Cu1	119.15 (16)

N1—C5—C6—N2	1.7 (6)	O3—Cu1—O1—C3ⁱ	−13.5 (5)
N1—C7—C8—N2	0.9 (4)	O2—Cu1—O1—C3ⁱ	78.2 (2)
N1—C7—C8—N3	−178.1 (3)	O4—Cu1—O1—C3ⁱ	−90.2 (2)
C8—C7—N1—C5	0.3 (4)	N1—Cu1—O1—C3ⁱ	170.5 (2)
C8—C7—N1—Cu1	−176.6 (2)	Cu1ⁱ—Cu1—O1—C3ⁱ	−2.7 (2)
C6—C5—N1—C7	−1.5 (5)	O3—Cu1—O2—C1ⁱ	81.6 (2)
C6—C5—N1—Cu1	175.3 (3)	O1—Cu1—O2—C1ⁱ	−86.6 (2)
O3—Cu1—N1—C7	85.5 (2)	O4—Cu1—O2—C1ⁱ	−2.8 (5)
O1—Cu1—N1—C7	−95.3 (2)	N1—Cu1—O2—C1ⁱ	176.3 (2)
O2—Cu1—N1—C7	−4.6 (2)	Cu1ⁱ—Cu1—O2—C1ⁱ	−2.0 (2)
O4—Cu1—N1—C7	175.2 (2)	O1ⁱ—C3—O3—Cu1	−1.4 (4)
Cu1ⁱ—Cu1—N1—C7	9.2 (6)	C4—C3—O3—Cu1	178.70 (18)
O3—Cu1—N1—C5	−91.3 (2)	O1—Cu1—O3—C3	13.4 (5)
O1—Cu1—N1—C5	87.9 (2)	O2—Cu1—O3—C3	−78.4 (2)
O2—Cu1—N1—C5	178.6 (2)	O4—Cu1—O3—C3	90.0 (2)
O4—Cu1—N1—C5	−1.6 (2)	N1—Cu1—O3—C3	−170.7 (2)
Cu1ⁱ—Cu1—N1—C5	−167.6 (4)	Cu1ⁱ—Cu1—O3—C3	2.6 (2)
C5—C6—N2—C8	−0.4 (5)	O2ⁱ—C1—O4—Cu1	3.5 (4)
N3—C8—N2—C6	178.2 (3)	C2—C1—O4—Cu1	−176.12 (18)
C7—C8—N2—C6	−0.8 (5)	O3—Cu1—O4—C1	−85.17 (19)
N2—C8—N3—C10	178.6 (3)	O1—Cu1—O4—C1	83.31 (19)
C7—C8—N3—C10	−2.4 (5)	O2—Cu1—O4—C1	−0.7 (5)
N2—C8—N3—C9	2.7 (5)	N1—Cu1—O4—C1	−179.80 (18)
C7—C8—N3—C9	−178.2 (3)	Cu1ⁱ—Cu1—O4—C1	−1.47 (18)

Symmetry code: (i) −x+1, −y+1, −z+2.

Experimental details

Crystal data
Chemical formula	[Cu₂(C₂H₃O₂)₄(C₆H₉N₃)₂]
M_r	609.58
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	8.1052 (13), 8.1775 (13), 10.6534 (17)
α, β, γ (°)	67.826 (2), 80.013 (2), 87.328 (2)
V (Å³)	643.84 (18)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	1.71
Crystal size (mm)	0.68 × 0.41 × 0.31

Data collection
Diffractometer	Bruker SMART APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.390, 0.620
No. of measured, independent and observed [I > 2σ(I)] reflections	3494, 2465, 2317
R_int	0.016
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.094, 1.09
No. of reflections	2465
No. of parameters	167
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.54, −0.44

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Cu1—O3	1.9649 (18)	Cu1—O4	1.9756 (18)
Cu1—O1	1.9654 (19)	Cu1—N1	2.197 (2)
Cu1—O2	1.9738 (18)

O3—Cu1—O1	168.16 (8)	O2—Cu1—O4	168.35 (7)
O3—Cu1—O2	89.93 (9)	O3—Cu1—N1	94.74 (8)
O1—Cu1—O2	90.44 (9)	O1—Cu1—N1	97.07 (8)
O3—Cu1—O4	88.93 (8)	O2—Cu1—N1	92.23 (8)
O1—Cu1—O4	88.32 (9)	O4—Cu1—N1	99.42 (8)

References

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