metal-organic compounds
Poly[tetra-μ1,1-azido-bis(μ2-pyrimidine-2-carboxylato)tricopper(II)]
aSchool of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300191, People's Republic of China
*Correspondence e-mail: fuchenliutj@yahoo.com
In the title compound, [Cu3(C5H3N2O2)2(N3)4]n, one of the CuII atoms lies on an inversion centre and is octahedrally coordinated by two bidentate chelating pyrimidine-2-carboxylate ligands and two azide anions, each of which gives an N:N-bridge to the second inversion-related CuII centre in the formula unit. The second CuII atom is five-coordinated with a distorted square-pyramidal coordination sphere comprising a single bidentate chelating pyrimidine-2-carboxylate anion and three azide N anions, two of which doubly bridge centrosymmetric CuII centres, giving a two-dimensional network structure extending parallel to (010).
Related literature
Copper azide complexes have attracted much attention in recent years because the azide anions can mediate magnetic interactions effectively between the copper ions, see: Zhao et al. (2009). The structures of the complexes are dependant on the co-ligand and conditions employed in the synthesis, see: Zeng et al. (2009). For azide complexes with 2,2′-bipyrimidine or oxalate as co-ligands, see: Cortes et al. (1996); Escuer et al. (1994) and for an azide complex with a pyrimidine-2-carboxylate ligand, see: Suarez-Varela et al. (2008).
Experimental
Crystal data
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Data collection: SCXmini Benchtop Crystallography System Software (Rigaku, 2006); cell PROCESS-AUTO (Rigaku, 1998); data reduction: PROCESS-AUTO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Supporting information
https://doi.org/10.1107/S1600536810027030/zs2045sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810027030/zs2045Isup2.hkl
A mixture of copper(II) nitrate (1.5mmol) and sodium azide (2 mmol), and pyrimidine-2-carboxylic acid (0.5 mmol) in 10 ml of water was sealed in a Teflon-lined stainless-steel Parr bomb that was heated at 413 K for 48 h. Black crystals of the title complex were collected after the bomb was allowed to cool to room temperature (yield 20% based on Cu). Caution:
may be explosive: although we have had no problems in this work, only small quantities should be prepared and should be handled with great caution.Hydrogen atoms were included in calculated positions and treated as riding on their parent C atoms with C—H = 0.93Å and Uiso(H) = 1.2Ueq(C).
Copper azide complexes have attracted much attention in recent years because the azide anions can mediate magnetic interactions effectively between the copper ions (Zhao et al., 2009). The structures of those complexes are dependant on the co-ligand and conditions employed in the synthesis (Zeng et al., 2009). Some azide complexes with 2,2'-bipyrimidine or oxalate as co-ligands have been reported (Cortes et al., 1996); Escuer et al., 1994). The pyrimidine-2-carboxylate ligand can be considered as the combination of 2,2'-bipyrimidine and oxalate, and a new metal azide complex with it as ligand has been reported (Suarez-Varela et al., 2008). In this work we report a new copper(II) azide complex with pyrimidine-2-carboxylate as co-ligand, [Cu3(C5H3N2O2)2(N3)4]n (I), prepared under hydrothermal conditions and its structure is reported here.
In the asymmetric units of the title compound, there are one and a half copper(II) cations, two azido anions and two pyrimidine-2-carboxylate ligands (Fig. 1). One of the cations (Cu2) lies on an inversion centre and is octahedrally coordinated by two bidentate chelate pyrimidine-2-carboxylato-N,O ligands and two azido anions, each giving an N bridge to the inversion-related Cu1 centres in the formula unit [Cu2—Cu1, 3.4652 (14) Å]. A second weak contact between a carboxyl O (O1) to Cu1 is also present [Cu1···O1, 2.950 (4) Å] but is too long to be considered a bridging (Cu–O) bond. The coordination sphere about Cu1 is five-coordinate with a distorted square pyramidal coordination sphere comprising a single bidentate chelate pyrimidine-2-carboxylate anion and three azido N anions, one bridging to Cu2, the other two giving double N bridges to centrosymmetrically related Cu centres [Cu1—Cu1iii, 3.329 (2) Å] [symmetry code: (iii) x -1, y, z]. Structure extension results in a two-dimensional network (Figs. 2, 3).
Copper azide complexes have attracted much attention in recent years because the azide anions can mediate magnetic interactions effectively between the copper ions, see: Zhao et al. (2009). The structures of the complexes are dependant on the co-ligand and conditions employed in the synthesis, see: Zeng et al. (2009). For azide complexes with 2,2'-bipyrimidine or oxalate as co-ligands, see: Cortes et al. (1996); Escuer et al. (1994) and for an azide complex with a pyrimidine-2-carboxylate ligand, see: Suarez-Varela et al. (2008).
Data collection: SCXmini Benchtop Crystallography System Software (Rigaku, 2006); cell
PROCESS-AUTO (Rigaku, 1998); data reduction: PROCESS-AUTO (Rigaku, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[Cu3(C5H3N2O2)2(N3)4] | F(000) = 594 |
Mr = 604.96 | Dx = 2.237 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 7433 reflections |
a = 7.4743 (15) Å | θ = 3.2–27.5° |
b = 14.997 (3) Å | µ = 3.59 mm−1 |
c = 9.479 (4) Å | T = 293 K |
β = 122.31 (2)° | Block, black |
V = 898.0 (5) Å3 | 0.20 × 0.18 × 0.18 mm |
Z = 2 |
Rigaku SCXmini CCD diffractometer | 1572 independent reflections |
Radiation source: fine-focus sealed tube | 1305 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.061 |
ω scans | θmax = 25.0°, θmin = 3.2° |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | h = −8→8 |
Tmin = 0.625, Tmax = 1.000 | k = −17→17 |
7028 measured reflections | l = −11→11 |
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)] = 0.052 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.134 | H-atom parameters constrained |
S = 1.24 | w = 1/[σ2(Fo2) + (0.0543P)2 + 2.0516P] where P = (Fo2 + 2Fc2)/3 |
1572 reflections | (Δ/σ)max < 0.001 |
151 parameters | Δρmax = 0.71 e Å−3 |
0 restraints | Δρmin = −0.46 e Å−3 |
[Cu3(C5H3N2O2)2(N3)4] | V = 898.0 (5) Å3 |
Mr = 604.96 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.4743 (15) Å | µ = 3.59 mm−1 |
b = 14.997 (3) Å | T = 293 K |
c = 9.479 (4) Å | 0.20 × 0.18 × 0.18 mm |
β = 122.31 (2)° |
Rigaku SCXmini CCD diffractometer | 1572 independent reflections |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | 1305 reflections with I > 2σ(I) |
Tmin = 0.625, Tmax = 1.000 | Rint = 0.061 |
7028 measured reflections |
R[F2 > 2σ(F2)] = 0.052 | 0 restraints |
wR(F2) = 0.134 | H-atom parameters constrained |
S = 1.24 | Δρmax = 0.71 e Å−3 |
1572 reflections | Δρmin = −0.46 e Å−3 |
151 parameters |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles |
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 | 0.64025 (11) | −0.01316 (5) | −0.29370 (10) | 0.0259 (3) | |
Cu2 | 0.50000 | 0.00000 | 0.00000 | 0.0221 (3) | |
O1 | 0.7728 (6) | −0.0882 (3) | 0.0359 (5) | 0.0278 (12) | |
O2 | 1.1215 (6) | −0.0703 (3) | 0.1528 (5) | 0.0234 (12) | |
N1 | 0.4612 (8) | 0.0444 (4) | −0.2223 (7) | 0.0279 (17) | |
N2 | 0.4377 (9) | 0.1253 (4) | −0.2455 (7) | 0.0344 (19) | |
N3 | 0.4134 (13) | 0.2001 (5) | −0.2695 (10) | 0.063 (3) | |
N4 | 0.4241 (9) | −0.0895 (4) | −0.4673 (7) | 0.0365 (19) | |
N5 | 0.2454 (9) | −0.0933 (4) | −0.4977 (6) | 0.035 (2) | |
N6 | 0.0719 (11) | −0.0987 (6) | −0.5367 (8) | 0.064 (3) | |
N7 | 1.1181 (8) | 0.0896 (3) | 0.2648 (6) | 0.0245 (17) | |
N8 | 0.7462 (8) | 0.0827 (3) | 0.1309 (6) | 0.0224 (17) | |
C1 | 0.9407 (9) | −0.0464 (4) | 0.1173 (7) | 0.0214 (17) | |
C2 | 0.9320 (9) | 0.0481 (4) | 0.1760 (7) | 0.0221 (17) | |
C3 | 0.7414 (11) | 0.1682 (4) | 0.1722 (9) | 0.033 (2) | |
C4 | 0.9286 (12) | 0.2167 (5) | 0.2647 (9) | 0.038 (3) | |
C5 | 1.1161 (11) | 0.1746 (4) | 0.3094 (8) | 0.032 (2) | |
H3A | 0.61250 | 0.19510 | 0.13880 | 0.0390* | |
H4A | 0.92720 | 0.27550 | 0.29530 | 0.0460* | |
H5A | 1.24310 | 0.20550 | 0.37130 | 0.0390* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0184 (4) | 0.0326 (5) | 0.0258 (5) | −0.0030 (3) | 0.0112 (4) | −0.0039 (3) |
Cu2 | 0.0168 (6) | 0.0274 (6) | 0.0215 (6) | −0.0014 (4) | 0.0099 (5) | −0.0009 (4) |
O1 | 0.026 (2) | 0.026 (2) | 0.030 (2) | −0.0038 (19) | 0.014 (2) | −0.0047 (19) |
O2 | 0.018 (2) | 0.028 (2) | 0.023 (2) | −0.0004 (17) | 0.0102 (18) | −0.0010 (18) |
N1 | 0.025 (3) | 0.031 (3) | 0.034 (3) | −0.001 (2) | 0.020 (3) | 0.001 (3) |
N2 | 0.029 (3) | 0.048 (4) | 0.035 (3) | −0.001 (3) | 0.023 (3) | −0.001 (3) |
N3 | 0.091 (6) | 0.032 (4) | 0.092 (6) | 0.014 (4) | 0.066 (5) | 0.011 (4) |
N4 | 0.026 (3) | 0.045 (4) | 0.035 (3) | −0.003 (3) | 0.014 (3) | −0.010 (3) |
N5 | 0.035 (4) | 0.050 (4) | 0.018 (3) | −0.012 (3) | 0.012 (3) | −0.002 (3) |
N6 | 0.034 (4) | 0.114 (7) | 0.040 (4) | −0.025 (4) | 0.018 (3) | −0.001 (4) |
N7 | 0.021 (3) | 0.024 (3) | 0.026 (3) | −0.005 (2) | 0.011 (2) | −0.003 (2) |
N8 | 0.021 (3) | 0.025 (3) | 0.022 (3) | −0.001 (2) | 0.012 (2) | −0.002 (2) |
C1 | 0.021 (3) | 0.026 (3) | 0.016 (3) | −0.001 (3) | 0.009 (3) | 0.000 (3) |
C2 | 0.027 (3) | 0.020 (3) | 0.022 (3) | 0.000 (3) | 0.015 (3) | 0.002 (2) |
C3 | 0.035 (4) | 0.029 (4) | 0.037 (4) | 0.007 (3) | 0.021 (3) | 0.002 (3) |
C4 | 0.047 (5) | 0.025 (4) | 0.041 (4) | 0.000 (3) | 0.022 (4) | −0.004 (3) |
C5 | 0.030 (4) | 0.035 (4) | 0.026 (4) | −0.011 (3) | 0.012 (3) | −0.004 (3) |
Cu1—N1 | 1.991 (7) | N2—N3 | 1.140 (10) |
Cu1—N4 | 1.946 (6) | N4—N5 | 1.208 (10) |
Cu1—N4i | 2.563 (6) | N5—N6 | 1.146 (12) |
Cu1—O2ii | 1.995 (5) | N7—C2 | 1.334 (9) |
Cu1—N7ii | 2.030 (6) | N7—C5 | 1.346 (8) |
Cu2—O1 | 2.298 (5) | N8—C2 | 1.321 (10) |
Cu2—N1 | 2.077 (6) | N8—C3 | 1.347 (8) |
Cu2—N8 | 2.006 (6) | C1—C2 | 1.537 (9) |
Cu2—O1iii | 2.298 (5) | C3—C4 | 1.394 (12) |
Cu2—N1iii | 2.077 (6) | C4—C5 | 1.381 (13) |
Cu2—N8iii | 2.006 (5) | C3—H3A | 0.9300 |
O1—C1 | 1.236 (8) | C4—H4A | 0.9300 |
O2—C1 | 1.258 (9) | C5—H5A | 0.9300 |
N1—N2 | 1.229 (8) | ||
N1—Cu1—N4 | 97.9 (3) | Cu1—N1—N2 | 115.2 (5) |
N1—Cu1—N4i | 101.4 (2) | Cu2—N1—N2 | 115.3 (5) |
O2ii—Cu1—N1 | 91.3 (2) | N1—N2—N3 | 178.9 (8) |
N1—Cu1—N7ii | 155.5 (2) | Cu1—N4—N5 | 122.8 (5) |
N4—Cu1—N4i | 85.8 (2) | Cu1—N4—Cu1i | 94.2 (2) |
O2ii—Cu1—N4 | 167.4 (2) | Cu1i—N4—N5 | 99.0 (4) |
N4—Cu1—N7ii | 93.4 (3) | N4—N5—N6 | 175.6 (7) |
O2ii—Cu1—N4i | 83.89 (19) | C2—N7—C5 | 117.2 (6) |
N4i—Cu1—N7ii | 101.0 (2) | Cu1ii—N7—C2 | 112.0 (4) |
O2ii—Cu1—N7ii | 81.5 (2) | Cu1ii—N7—C5 | 130.6 (5) |
O1—Cu2—N1 | 88.1 (2) | Cu2—N8—C2 | 114.5 (4) |
O1—Cu2—N8 | 79.4 (2) | Cu2—N8—C3 | 127.6 (6) |
O1—Cu2—O1iii | 180.00 | C2—N8—C3 | 117.8 (6) |
O1—Cu2—N1iii | 91.9 (2) | O1—C1—O2 | 127.6 (6) |
O1—Cu2—N8iii | 100.6 (2) | O1—C1—C2 | 117.9 (6) |
N1—Cu2—N8 | 90.8 (2) | O2—C1—C2 | 114.4 (6) |
O1iii—Cu2—N1 | 91.9 (2) | N7—C2—N8 | 125.6 (6) |
N1—Cu2—N1iii | 180.00 | N7—C2—C1 | 115.3 (6) |
N1—Cu2—N8iii | 89.2 (2) | N8—C2—C1 | 119.1 (6) |
O1iii—Cu2—N8 | 100.6 (2) | N8—C3—C4 | 120.4 (8) |
N1iii—Cu2—N8 | 89.2 (2) | C3—C4—C5 | 117.9 (7) |
N8—Cu2—N8iii | 180.00 | N7—C5—C4 | 121.1 (7) |
O1iii—Cu2—N1iii | 88.1 (2) | N8—C3—H3A | 120.00 |
O1iii—Cu2—N8iii | 79.4 (2) | C4—C3—H3A | 120.00 |
N1iii—Cu2—N8iii | 90.8 (2) | C3—C4—H4A | 121.00 |
Cu2—O1—C1 | 109.0 (4) | C5—C4—H4A | 121.00 |
Cu1ii—O2—C1 | 116.6 (4) | N7—C5—H5A | 119.00 |
Cu1—N1—Cu2 | 116.8 (3) | C4—C5—H5A | 119.00 |
O1—Cu1—N1—N2 | 136.0 (5) | N8—Cu2—N1—Cu1 | 84.3 (3) |
N4—Cu1—N1—Cu2 | 103.7 (3) | N8—Cu2—N1—N2 | −55.7 (6) |
N4—Cu1—N1—N2 | −116.3 (5) | O1iii—Cu2—N1—Cu1 | −175.1 (3) |
N4i—Cu1—N1—Cu2 | −169.0 (3) | O1iii—Cu2—N1—N2 | 44.9 (6) |
N4i—Cu1—N1—N2 | −28.9 (5) | N8iii—Cu2—N1—Cu1 | −95.7 (3) |
O2ii—Cu1—N1—Cu2 | −84.9 (3) | N8iii—Cu2—N1—N2 | 124.3 (6) |
O2ii—Cu1—N1—N2 | 55.1 (5) | O1—Cu2—N8—C2 | −2.2 (4) |
N7ii—Cu1—N1—Cu2 | −12.9 (8) | O1—Cu2—N8—C3 | 175.8 (6) |
N7ii—Cu1—N1—N2 | 127.2 (6) | N1—Cu2—N8—C2 | −90.1 (5) |
O1—Cu1—N4—N5 | 72.4 (6) | N1—Cu2—N8—C3 | 87.9 (6) |
O1—Cu1—N4—Cu1i | 175.86 (15) | O1iii—Cu2—N8—C2 | 177.8 (4) |
N1—Cu1—N4—N5 | −2.6 (6) | O1iii—Cu2—N8—C3 | −4.3 (6) |
N1—Cu1—N4—Cu1i | 100.9 (2) | N1iii—Cu2—N8—C2 | 89.9 (5) |
N4i—Cu1—N4—N5 | −103.5 (6) | N1iii—Cu2—N8—C3 | −92.2 (6) |
N4i—Cu1—N4—Cu1i | 0.0 (2) | Cu1—O1—C1—O2 | −91.6 (6) |
N7ii—Cu1—N4—N5 | 155.7 (6) | Cu1—O1—C1—C2 | 84.7 (5) |
N7ii—Cu1—N4—Cu1i | −100.8 (2) | Cu2—O1—C1—O2 | −175.2 (5) |
N1—Cu1—N4i—Cu1i | −97.2 (3) | Cu2—O1—C1—C2 | 1.2 (6) |
N1—Cu1—N4i—N5i | 138.6 (4) | Cu1ii—O2—C1—O1 | −178.1 (5) |
N4—Cu1—N4i—Cu1i | 0.0 (3) | Cu1ii—O2—C1—C2 | 5.5 (6) |
N4—Cu1—N4i—N5i | −124.2 (5) | C5—N7—C2—N8 | −1.4 (9) |
O1—Cu1—O2ii—C1ii | 87.9 (4) | C5—N7—C2—C1 | 175.8 (5) |
N1—Cu1—O2ii—C1ii | 160.8 (4) | Cu1ii—N7—C2—N8 | −176.8 (5) |
O1—Cu1—N7ii—C2ii | −84.5 (4) | Cu1ii—N7—C2—C1 | 0.4 (6) |
O1—Cu1—N7ii—C5ii | 90.1 (6) | C2—N7—C5—C4 | 0.0 (10) |
N1—Cu1—N7ii—C2ii | −75.9 (7) | Cu1ii—N7—C5—C4 | 174.4 (5) |
N1—Cu1—N7ii—C5ii | 98.7 (7) | Cu2—N8—C2—N7 | −179.3 (5) |
N4—Cu1—N7ii—C2ii | 166.6 (4) | Cu2—N8—C2—C1 | 3.6 (7) |
N4—Cu1—N7ii—C5ii | −18.8 (6) | C3—N8—C2—N7 | 2.6 (9) |
N1—Cu2—O1—Cu1 | −2.98 (18) | C3—N8—C2—C1 | −174.6 (6) |
N1—Cu2—O1—C1 | 91.6 (4) | Cu2—N8—C3—C4 | 179.9 (5) |
N8—Cu2—O1—Cu1 | −94.14 (17) | C2—N8—C3—C4 | −2.2 (10) |
N8—Cu2—O1—C1 | 0.4 (4) | O1—C1—C2—N7 | 179.3 (5) |
N1iii—Cu2—O1—Cu1 | 177.02 (18) | O1—C1—C2—N8 | −3.3 (8) |
N1iii—Cu2—O1—C1 | −88.4 (4) | O2—C1—C2—N7 | −3.9 (8) |
N8iii—Cu2—O1—Cu1 | 85.86 (17) | O2—C1—C2—N8 | 173.5 (5) |
N8iii—Cu2—O1—C1 | −179.6 (4) | N8—C3—C4—C5 | 1.0 (11) |
O1—Cu2—N1—Cu1 | 4.9 (3) | C3—C4—C5—N7 | 0.2 (11) |
O1—Cu2—N1—N2 | −135.1 (6) |
Symmetry codes: (i) −x+1, −y, −z−1; (ii) −x+2, −y, −z; (iii) −x+1, −y, −z. |
Experimental details
Crystal data | |
Chemical formula | [Cu3(C5H3N2O2)2(N3)4] |
Mr | 604.96 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 7.4743 (15), 14.997 (3), 9.479 (4) |
β (°) | 122.31 (2) |
V (Å3) | 898.0 (5) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 3.59 |
Crystal size (mm) | 0.20 × 0.18 × 0.18 |
Data collection | |
Diffractometer | Rigaku SCXmini CCD diffractometer |
Absorption correction | Multi-scan (ABSCOR; Higashi, 1995) |
Tmin, Tmax | 0.625, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7028, 1572, 1305 |
Rint | 0.061 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.052, 0.134, 1.24 |
No. of reflections | 1572 |
No. of parameters | 151 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.71, −0.46 |
Computer programs: SCXmini Benchtop Crystallography System Software (Rigaku, 2006), PROCESS-AUTO (Rigaku, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008).
Acknowledgements
The authors acknowledge financial support from Tianjin Municipal Education Commission (grant No. 20060503).
References
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Copper azide complexes have attracted much attention in recent years because the azide anions can mediate magnetic interactions effectively between the copper ions (Zhao et al., 2009). The structures of those complexes are dependant on the co-ligand and conditions employed in the synthesis (Zeng et al., 2009). Some azide complexes with 2,2'-bipyrimidine or oxalate as co-ligands have been reported (Cortes et al., 1996); Escuer et al., 1994). The pyrimidine-2-carboxylate ligand can be considered as the combination of 2,2'-bipyrimidine and oxalate, and a new metal azide complex with it as ligand has been reported (Suarez-Varela et al., 2008). In this work we report a new copper(II) azide complex with pyrimidine-2-carboxylate as co-ligand, [Cu3(C5H3N2O2)2(N3)4]n (I), prepared under hydrothermal conditions and its structure is reported here.
In the asymmetric units of the title compound, there are one and a half copper(II) cations, two azido anions and two pyrimidine-2-carboxylate ligands (Fig. 1). One of the cations (Cu2) lies on an inversion centre and is octahedrally coordinated by two bidentate chelate pyrimidine-2-carboxylato-N,O ligands and two azido anions, each giving an N bridge to the inversion-related Cu1 centres in the formula unit [Cu2—Cu1, 3.4652 (14) Å]. A second weak contact between a carboxyl O (O1) to Cu1 is also present [Cu1···O1, 2.950 (4) Å] but is too long to be considered a bridging (Cu–O) bond. The coordination sphere about Cu1 is five-coordinate with a distorted square pyramidal coordination sphere comprising a single bidentate chelate pyrimidine-2-carboxylate anion and three azido N anions, one bridging to Cu2, the other two giving double N bridges to centrosymmetrically related Cu centres [Cu1—Cu1iii, 3.329 (2) Å] [symmetry code: (iii) x -1, y, z]. Structure extension results in a two-dimensional network (Figs. 2, 3).