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metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 7| July 2011| Pages m822-m823
doi:10.1107/S1600536811019453

Poly[[di­aquadi-μ2-cyanido-bis­­(μ2-pyrazine-2-carboxyl­ato)dicopper(I)copper(II)] dihydrate]

Guang Fan,a,b* Jia-juan Sun,a Min-yan Zheng,a San-ping Chenb and Sheng-Li Gaob

aCollege of Chemistry & Chemical Engineering, Xianyang Normal University, Xianyang 712000, Shaanxi, People's Republic of China, and bCollege of Chemistry & Materials Science, Northwest University, Xi'an 710069, Shaanxi, People's Republic of China
*Correspondence e-mail: fanguang2004@163.com

(Received 14 April 2011; accepted 23 May 2011; online 4 June 2011)

In the title compound, {[CuIICuI2(C5H3N2O2)2(CN)2(H2O)2]·2H2O}n, the CuII atom lies on an inversion centre and is octa­hedrally coordinated by two N atoms and two O atoms from opposing pyrazine-2-carboxyl­ate (2-pac) ligands and two water O atoms. The CuI atom has a triangular geometry, coordinated by one N atom and one C atom from two bridging cyanide ligands, and another N atom from the 2-pac ligand. The three-dimensional structure features a succession of two-dimensional sheets containing [Cu(CN)]n chains linked by Cu(2-pac)2(H2O)2 groups. The coordinated and free water mol­ecules are involved in an extended three-dimensional hydrogen-bond network with the 2-pac ligands.

Related literature

For applications of metal-organic frameworks (MOFs), see: Klein et al. (1982[Klein, C. L., Majeste, R. J., Trefonas, L. M. & O'Connor, C. J. (1982). Inorg. Chem. 21, 1891-1897.]); Li et al. (2004[Li, X. J., Cao, R., Sun, D. F., Bi, W. H., Wang, Y. Q., Li, X. & Hong, M. C. (2004). Cryst. Growth Des. 4, 775-780.]); Plater et al. (2001[Plater, M. J., Foreman, M. R., Howie, R. A., Skakle, J. M., SMcWilliam, S. A., Coronado, E. G. & Gomez-Garcia, C. J. (2001). Polyhedron, 20, 2293-2303.]); Thomas (1978[Thomas, J. M. (1978). Acc. Chem. Res. 11, 94-100.]). For a related structure, see: Fan et al. (2006[Fan, G., Chen, S. P. & Gao, S. L. (2006). J. Coord. Chem. 7, 791-795.]).

[Scheme 1]

Experimental

Crystal data

  • [Cu3(C5H3N2O2)2(CN)2(H2O)2]·2H2O

  • Mr = 560.91

  • Monoclinic, P 21 /c

  • a = 13.8297 (4) Å

  • b = 9.4906 (3) Å

  • c = 7.1272 (3) Å

  • β = 100.768 (3)°

  • V = 918.99 (6) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 3.50 mm−1

  • T = 296 K

  • 0.10 × 0.08 × 0.05 mm
Data collection

  • Bruker SMART APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996)[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.] Tmin = 0.721, Tmax = 0.845

  • 4141 measured reflections

  • 1615 independent reflections

  • 1269 reflections with I > 2σ(I)

  • Rint = 0.022
Refinement

  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.095

  • S = 0.99

  • 1615 reflections

  • 145 parameters

  • 6 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.36 e Å−3

Table 1
Selected bond lengths (Å)

Cu1—O1 1.978 (2)
Cu1—N1 2.003 (3)
Cu1—O3 2.378 (3)
Cu2—C6 1.865 (3)
Cu2—N3i 1.886 (4)
Cu2—N2 2.163 (3)
Symmetry code: (i) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O4—H4A⋯O2 0.86 (2) 2.08 (3) 2.910 (5) 160 (7)
O3—H3B⋯O1ii 0.82 (2) 2.11 (2) 2.883 (3) 156 (4)
O3—H3A⋯O2iii 0.84 (2) 1.94 (2) 2.783 (4) 172 (4)
Symmetry codes: (ii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL/PC (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL/PC.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811019453/vn2007sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811019453/vn2007Isup2.hkl

checkCIF report


Comment top

Single crystal diffraction has revealed that complex (I) crystallizes in the monoclinic space group P21/c featuring two-dimensional networks through chain-like [Cu(CN)]n units linked by Cu(2-pac)2(H2O)2. As shown in Fig. 1, there are two crystallographic inequivalent copper atoms. The Cu(1) atom is divalent and Cu(2) is monovalent. Cu(1) adopts a distorted octahedral geometry by two N and two O atoms from the 2-pac ligands in the equatorial plane whereas the axial positions are occupied by two water molecules with 1.9781 (17)Å for Cu1—O1; 2.002 (2)Å for Cu1—N1; 2.371 (2)Å for Cu1—O3. Each Cu(2) atom has a triangular geometry, coordinated to one N atom and one C atom from two bridging cyanide ligands and another N atom from Cu(2-pac)2(H2O)2, with 1.860 (3)Å for Cu2—C6; 1.885 (3)Å for Cu2—N3; 2.163 (2)Å for Cu2—N2.

Fig. 2 shows the independent cyanide ligands bridging Cu(2) to form a zigzag chain of [Cu(CN)]n units. Such chains are interconnected through two Cu(2-pac)2(H2O)2 N donor ligands giving rise to a two-dimensional sheet network. Furthermore, an extensive hydrogen bonding network is formed, which involves the coordinated, free water molecules and the 2-pac ligand substituents, affording a three-dimensional network, as shown in Fig. 3. It is noted that one proton of the free water molecule has no apparent hydrogen acceptor atom.

The present structure is quite different from the mixed-valence copper complex [CuIICuI(2-pac)2(NO3)(H2O)]n reported by Fan et al. (2006). In the latter structure the coordination number of monovalent Cu atom is 4, but for the present structure the coordination number is 3.

Related literature top

For applications [of what?], see: Klein et al. (1982); Li et al. (2004); Plater et al. (2001); Thomas (1978). For a related structure, see: Fan et al. (2006).

Experimental top

Red crystals from complex (I) were obtained by hydrothermal synthesis of a mixture of Cu(NO3)2.3H2O (0.1241 g, 0.5 mmol), 0.4 ml H3PO3 and 2-pac (0.0673 g, 0.5 mmol) in 6 ml H2O, sealed in a Teflon-lined stainless container, heated at 363 K for 24 h and slowly cooled to room temperature.

Refinement top

All H atoms attached to C atoms from the organic ligands were generated in idealized positions and constrained to ride on their parent atoms, with d(C—H) = 0.93 Å, Uiso=1.2Ueq (C). The water H-atoms were located in a different Fourier map, and the geometry of the two water molecules was restrained to its ideal geometry by in total six restraints on angles and bond distances.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXTL/PC (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of (I) with the atom-labeling scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Symmetry code for A: 1-x, -y, -z; B: –x, -0.5+y, 0.5-z.
[Figure 2] Fig. 2. Two-dimensional sheet structure for complex (I). Hydrogen atoms have been omitted for clarity.
[Figure 3] Fig. 3. Three-dimensional stacking diagram for complex (I) along the c axis.
Poly[[diaquadi-µ2-cyanido-bis(µ2-pyrazine-2-carboxylato)dicopper(I)copper(II)] dihydrate] top
Crystal data top
[Cu3(C5H3N2O2)2(CN)2(H2O)2]·2H2OF(000) = 558
Mr = 560.91Dx = 2.027 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 117 reflections
a = 13.8297 (4) Åθ = 2.5–19.1°
b = 9.4906 (3) ŵ = 3.50 mm−1
c = 7.1272 (3) ÅT = 296 K
β = 100.768 (3)°Block, red
V = 918.99 (6) Å30.10 × 0.08 × 0.05 mm
Z = 2
Data collection top
Bruker SMART APEXII CCD
diffractometer		1615 independent reflections
Radiation source: fine-focus sealed tube1269 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
ϕ and ω scansθmax = 25.1°, θmin = 3.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −16→16
Tmin = 0.721, Tmax = 0.845k = −11→11
4141 measured reflectionsl = −7→8
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.095H atoms treated by a mixture of independent and constrained refinement
S = 0.99 w = 1/[σ2(Fo2) + (0.0484P)2 + 1.5206P]
where P = (Fo2 + 2Fc2)/3
1615 reflections(Δ/σ)max < 0.001
145 parametersΔρmax = 0.36 e Å−3
6 restraintsΔρmin = −0.36 e Å−3
Crystal data top
[Cu3(C5H3N2O2)2(CN)2(H2O)2]·2H2OV = 918.99 (6) Å3
Mr = 560.91Z = 2
Monoclinic, P21/cMo Kα radiation
a = 13.8297 (4) ŵ = 3.50 mm−1
b = 9.4906 (3) ÅT = 296 K
c = 7.1272 (3) Å0.10 × 0.08 × 0.05 mm
β = 100.768 (3)°
Data collection top
Bruker SMART APEXII CCD
diffractometer		1615 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		1269 reflections with I > 2σ(I)
Tmin = 0.721, Tmax = 0.845Rint = 0.022
4141 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0296 restraints
wR(F2) = 0.095H atoms treated by a mixture of independent and constrained refinement
S = 0.99Δρmax = 0.36 e Å−3
1615 reflectionsΔρmin = −0.36 e Å−3
145 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
xyzUiso*/Ueq
Cu10.50000.00000.00000.0296 (2)
Cu20.03571 (3)0.00934 (4)0.21527 (8)0.0366 (2)
O10.45839 (17)0.1989 (2)−0.0394 (4)0.0316 (6)
O20.33417 (17)0.3429 (2)−0.0167 (4)0.0356 (6)
O30.5540 (2)0.0613 (3)0.3263 (4)0.0433 (7)
H3A0.588 (3)−0.001 (4)0.393 (6)0.065*
H3B0.524 (3)0.113 (4)0.390 (6)0.065*
C50.3724 (2)0.2253 (3)−0.0104 (5)0.0258 (7)
N10.3627 (2)−0.0237 (3)0.0479 (5)0.0297 (7)
N20.1722 (2)−0.0069 (3)0.1101 (5)0.0330 (7)
N3−0.0012 (2)0.3197 (4)0.2534 (5)0.0422 (8)
C10.3146 (2)0.0996 (3)0.0357 (5)0.0253 (7)
C40.3148 (3)−0.1381 (4)0.0874 (6)0.0401 (10)
H40.3458−0.22540.09410.048*
C20.2195 (2)0.1067 (3)0.0676 (5)0.0293 (8)
H20.18770.19350.05910.035*
C60.0122 (2)0.2013 (3)0.2401 (5)0.0288 (8)
C30.2199 (3)−0.1284 (4)0.1185 (6)0.0405 (10)
H30.1881−0.21000.14630.049*
O40.1922 (3)0.5271 (4)0.1144 (8)0.0884 (13)
H4A0.229 (4)0.457 (5)0.093 (11)0.133*
H4B0.133 (2)0.495 (7)0.108 (13)0.133*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.0222 (3)0.0210 (3)0.0499 (4)0.0014 (2)0.0178 (3)0.0025 (2)
Cu20.0345 (3)0.0214 (3)0.0572 (4)−0.00078 (17)0.0176 (2)−0.0008 (2)
O10.0256 (12)0.0243 (12)0.0487 (16)−0.0007 (10)0.0170 (11)0.0041 (11)
O20.0297 (12)0.0217 (13)0.0564 (18)0.0009 (10)0.0109 (12)0.0014 (11)
O30.0502 (17)0.0366 (16)0.0452 (18)0.0128 (13)0.0138 (14)−0.0037 (13)
C50.0267 (17)0.0226 (17)0.029 (2)−0.0009 (13)0.0070 (15)−0.0010 (14)
N10.0240 (14)0.0234 (15)0.0449 (19)0.0010 (12)0.0147 (14)0.0007 (13)
N20.0267 (15)0.0260 (16)0.050 (2)−0.0008 (11)0.0173 (15)0.0018 (13)
N30.0386 (17)0.042 (2)0.050 (2)0.0022 (15)0.0172 (16)0.0012 (16)
C10.0251 (16)0.0212 (17)0.031 (2)0.0003 (13)0.0079 (14)−0.0012 (14)
C40.036 (2)0.0215 (18)0.068 (3)0.0060 (15)0.023 (2)0.0058 (18)
C20.0248 (17)0.0225 (18)0.042 (2)−0.0004 (14)0.0106 (16)−0.0012 (15)
C60.0322 (18)0.0183 (17)0.039 (2)0.0033 (14)0.0139 (16)−0.0011 (15)
C30.0326 (19)0.0267 (19)0.068 (3)−0.0008 (16)0.0245 (19)0.0055 (19)
O40.082 (3)0.077 (3)0.115 (4)0.013 (2)0.043 (3)−0.001 (3)
Geometric parameters (Å, º) top
Cu1—O1i1.978 (2)C5—C11.507 (4)
Cu1—O11.978 (2)N1—C41.329 (4)
Cu1—N1i2.003 (3)N1—C11.340 (4)
Cu1—N12.003 (3)N2—C31.324 (5)
Cu1—O3i2.378 (3)N2—C21.326 (4)
Cu1—O32.378 (3)N3—C61.146 (5)
Cu2—C61.865 (3)N3—Cu2iv1.886 (4)
Cu2—N3ii1.886 (4)C1—C21.377 (5)
Cu2—N22.163 (3)C4—C31.375 (5)
Cu2—Cu2iii3.0481 (11)C4—H40.9300
O1—C51.269 (4)C2—H20.9300
O2—C51.232 (4)C3—H30.9300
O3—H3A0.844 (19)O4—H4A0.86 (2)
O3—H3B0.824 (19)O4—H4B0.87 (2)
O1i—Cu1—O1180.00 (14)O2—C5—O1125.6 (3)
O1i—Cu1—N1i82.62 (10)O2—C5—C1118.9 (3)
O1—Cu1—N1i97.38 (10)O1—C5—C1115.5 (3)
O1i—Cu1—N197.38 (10)C4—N1—C1117.8 (3)
O1—Cu1—N182.62 (10)C4—N1—Cu1130.8 (2)
N1i—Cu1—N1180.00 (3)C1—N1—Cu1111.5 (2)
O1i—Cu1—O3i86.28 (10)C3—N2—C2117.1 (3)
O1—Cu1—O3i93.72 (10)C3—N2—Cu2120.4 (2)
N1i—Cu1—O3i89.72 (11)C2—N2—Cu2121.4 (2)
N1—Cu1—O3i90.28 (11)C6—N3—Cu2iv173.8 (3)
O1i—Cu1—O393.72 (10)N1—C1—C2120.7 (3)
O1—Cu1—O386.28 (10)N1—C1—C5115.4 (3)
N1i—Cu1—O390.28 (11)C2—C1—C5124.0 (3)
N1—Cu1—O389.72 (11)N1—C4—C3120.6 (3)
O3i—Cu1—O3180.00 (14)N1—C4—H4119.7
C6—Cu2—N3ii150.28 (16)C3—C4—H4119.7
C6—Cu2—N2106.34 (13)N2—C2—C1121.7 (3)
N3ii—Cu2—N2103.29 (12)N2—C2—H2119.2
C6—Cu2—Cu2iii97.07 (12)C1—C2—H2119.2
N3ii—Cu2—Cu2iii91.27 (11)N3—C6—Cu2178.9 (4)
N2—Cu2—Cu2iii77.67 (9)N2—C3—C4122.2 (3)
C5—O1—Cu1114.9 (2)N2—C3—H3118.9
Cu1—O3—H3A115 (3)C4—C3—H3118.9
Cu1—O3—H3B126 (3)H4A—O4—H4B107 (4)
H3A—O3—H3B113 (3)
Symmetry codes: (i) −x+1, −y, −z; (ii) −x, y−1/2, −z+1/2; (iii) −x, −y, −z; (iv) −x, y+1/2, −z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4A···O20.86 (2)2.08 (3)2.910 (5)160 (7)
O3—H3B···O1v0.82 (2)2.11 (2)2.883 (3)156 (4)
O3—H3A···O2vi0.84 (2)1.94 (2)2.783 (4)172 (4)
Symmetry codes: (v) x, −y+1/2, z+1/2; (vi) −x+1, y−1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula[Cu3(C5H3N2O2)2(CN)2(H2O)2]·2H2O
Mr560.91
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)13.8297 (4), 9.4906 (3), 7.1272 (3)
β (°) 100.768 (3)
V (Å3)918.99 (6)
Z2
Radiation typeMo Kα
µ (mm−1)3.50
Crystal size (mm)0.10 × 0.08 × 0.05
Data collection
DiffractometerBruker SMART APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.721, 0.845
No. of measured, independent and
observed [I > 2σ(I)] reflections		4141, 1615, 1269
Rint0.022
(sin θ/λ)max (Å−1)0.596
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.095, 0.99
No. of reflections1615
No. of parameters145
No. of restraints6
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.36, −0.36

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL/PC (Sheldrick, 2008).

Selected bond lengths (Å) top
Cu1—O11.978 (2)Cu2—C61.865 (3)
Cu1—N12.003 (3)Cu2—N3i1.886 (4)
Cu1—O32.378 (3)Cu2—N22.163 (3)
Symmetry code: (i) −x, y−1/2, −z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4A···O20.86 (2)2.08 (3)2.910 (5)160 (7)
O3—H3B···O1ii0.824 (19)2.11 (2)2.883 (3)156 (4)
O3—H3A···O2iii0.844 (19)1.944 (19)2.783 (4)172 (4)
Symmetry codes: (ii) x, −y+1/2, z+1/2; (iii) −x+1, y−1/2, −z+1/2.
 

Acknowledgements

We gratefully acknowledge the Natural Science Foundation of Shaanxi Province (2009JQ2015, 2010JM2009), the Special Research Fund of the Education Department of Shaanxi Province (09 J K798, 2010 J K902) and the Open Fund of the Key Laboratory of Synthetic and Natural Functional Mol­ec­ular Chemistry of the Ministry of Education at Northwest University.

References

First citationBruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationFan, G., Chen, S. P. & Gao, S. L. (2006). J. Coord. Chem. 7, 791–795.  CrossRef Google Scholar
 First citationKlein, C. L., Majeste, R. J., Trefonas, L. M. & O'Connor, C. J. (1982). Inorg. Chem. 21, 1891–1897.  CSD CrossRef CAS Web of Science Google Scholar
 First citationLi, X. J., Cao, R., Sun, D. F., Bi, W. H., Wang, Y. Q., Li, X. & Hong, M. C. (2004). Cryst. Growth Des. 4, 775–780.  Web of Science CSD CrossRef CAS Google Scholar
 First citationPlater, M. J., Foreman, M. R., Howie, R. A., Skakle, J. M., SMcWilliam, S. A., Coronado, E. G. & Gomez-Garcia, C. J. (2001). Polyhedron, 20, 2293–2303.  CrossRef Google Scholar
 First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationThomas, J. M. (1978). Acc. Chem. Res. 11, 94–100.  CrossRef Web of Science Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 7| July 2011| Pages m822-m823
doi:10.1107/S1600536811019453
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