metal-organic compounds
Poly[bis[μ-1,4-bis(imidazol-1-yl)butane]dicyanatocadmium(II)]
aScience College, Civil Aviation University of China, Tianjin 300300, People's Republic of China
*Correspondence e-mail: xzhu@cauc.edu.cn
The coordination geometry of the CdII atom in the title complex, [Cd(NCO)2(C10H14N4)2]n or [Cd(NCO)2(bimb)2]n, where bimb is 1,4-bis(imidazol-1-yl)butane, is distorted octahedral with the CdII atom located on an inversion center and connected to four N atoms from the imidazole units of four symmetry-related bimb ligands and two O atoms from two symmetry-related NCO− ligands. The CdII atoms are bridged by four bimb ligands, forming a two-dimensional (4,4) network.
Related literature
For the synthesis and structure of 1,4-bis(imidazol-1-yl)butane (bimb) complexes, see: Duncan et al. (1996); Ma et al. (2000); Yang et al. (2005); Zhang et al. (2008).
Experimental
Crystal data
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Refinement
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Data collection: CrystalClear (Rigaku, 2000); cell CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536809043104/gk2236sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809043104/gk2236Isup2.hkl
A 20 ml H2O/MeOH solution (1:1 v/v) of Cd(NO3)2.4H2O (0.154 g, 0.5 mmol) was added to one leg of an "H-shaped" tube, and a 20 ml H2O/MeOH (1:1 v/v) solution of bimb (0.190 g, 1.0 mmol) and NaNCO (0.065 g, 1.0 mmol) was added to the other leg of the tube. After two weeks, the well shaped colorless single crystals 1 were obtained. Yield: 64%. Found: C, 45.67; H, 4.82; N, 24.16. Calcd. for C22H28CdN10O2 (1): C, 45.80; H, 4.89; N, 24.28%.
H atom were placed in idealized positions and refined as riding, with C—H distances of 0.95 (imidazole) and 0.99Å (butane), and with Uiso(H) = 1.2 times Ueq(C).
Data collection: CrystalClear (Rigaku, 2000); cell
CrystalClear (Rigaku, 2000); data reduction: CrystalClear (Rigaku, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[Cd(NCO)2(C10H14N4)2] | F(000) = 588 |
Mr = 576.94 | Dx = 1.618 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71070 Å |
Hall symbol: -P 2ybc | Cell parameters from 4682 reflections |
a = 7.7760 (14) Å | θ = 3.1–25.4° |
b = 18.156 (3) Å | µ = 0.96 mm−1 |
c = 9.0983 (16) Å | T = 153 K |
β = 112.776 (3)° | Block, colorless |
V = 1184.4 (4) Å3 | 0.45 × 0.35 × 0.30 mm |
Z = 2 |
Rigaku Mercury CCD diffractometer | 2163 independent reflections |
Radiation source: fine-focus sealed tube | 2066 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.018 |
ω scans | θmax = 25.3°, θmin = 3.1° |
Absorption correction: multi-scan (Jacobson, 1998) | h = −9→9 |
Tmin = 0.671, Tmax = 0.761 | k = −21→19 |
11270 measured reflections | l = −9→10 |
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)] = 0.021 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.056 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.031P)2 + 0.9885P] where P = (Fo2 + 2Fc2)/3 |
2163 reflections | (Δ/σ)max < 0.001 |
161 parameters | Δρmax = 0.32 e Å−3 |
0 restraints | Δρmin = −0.37 e Å−3 |
[Cd(NCO)2(C10H14N4)2] | V = 1184.4 (4) Å3 |
Mr = 576.94 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.7760 (14) Å | µ = 0.96 mm−1 |
b = 18.156 (3) Å | T = 153 K |
c = 9.0983 (16) Å | 0.45 × 0.35 × 0.30 mm |
β = 112.776 (3)° |
Rigaku Mercury CCD diffractometer | 2163 independent reflections |
Absorption correction: multi-scan (Jacobson, 1998) | 2066 reflections with I > 2σ(I) |
Tmin = 0.671, Tmax = 0.761 | Rint = 0.018 |
11270 measured reflections |
R[F2 > 2σ(F2)] = 0.021 | 0 restraints |
wR(F2) = 0.056 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.32 e Å−3 |
2163 reflections | Δρmin = −0.37 e Å−3 |
161 parameters |
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 | ||
Cd1 | 1.0000 | 0.5000 | 0.5000 | 0.01448 (8) | |
O1 | 0.4601 (2) | 0.59262 (11) | 0.2107 (2) | 0.0527 (5) | |
N1 | 0.8341 (2) | 0.58976 (8) | 0.88528 (18) | 0.0175 (3) | |
N2 | 0.9580 (2) | 0.54469 (8) | 0.72359 (18) | 0.0176 (3) | |
N3 | 0.1518 (2) | 0.78895 (8) | 0.82212 (18) | 0.0192 (3) | |
N4 | 0.0347 (2) | 0.87774 (8) | 0.92119 (18) | 0.0185 (3) | |
N5 | 0.6775 (3) | 0.50356 (9) | 0.3636 (2) | 0.0261 (4) | |
C1 | 0.6951 (3) | 0.61731 (12) | 0.9447 (2) | 0.0247 (4) | |
H1A | 0.7592 | 0.6460 | 1.0435 | 0.030* | |
H1B | 0.6323 | 0.5750 | 0.9715 | 0.030* | |
C2 | 0.5502 (3) | 0.66549 (10) | 0.8233 (2) | 0.0191 (4) | |
H2A | 0.4667 | 0.6342 | 0.7356 | 0.023* | |
H2B | 0.6135 | 0.7005 | 0.7775 | 0.023* | |
C3 | 0.4331 (3) | 0.70868 (10) | 0.8957 (2) | 0.0188 (4) | |
H3A | 0.3794 | 0.6745 | 0.9514 | 0.023* | |
H3B | 0.5131 | 0.7446 | 0.9746 | 0.023* | |
C4 | 0.2777 (3) | 0.74894 (12) | 0.7648 (2) | 0.0255 (4) | |
H4A | 0.3335 | 0.7843 | 0.7130 | 0.031* | |
H4B | 0.2042 | 0.7128 | 0.6831 | 0.031* | |
C5 | 0.8009 (3) | 0.56271 (10) | 0.7382 (2) | 0.0182 (4) | |
H5A | 0.6804 | 0.5574 | 0.6562 | 0.022* | |
C6 | 1.0980 (3) | 0.56036 (10) | 0.8684 (2) | 0.0189 (4) | |
H6A | 1.2273 | 0.5528 | 0.8940 | 0.023* | |
C7 | 1.0241 (3) | 0.58814 (10) | 0.9689 (2) | 0.0201 (4) | |
H7A | 1.0902 | 0.6035 | 1.0759 | 0.024* | |
C8 | 0.1767 (3) | 0.85724 (10) | 0.8854 (2) | 0.0187 (4) | |
H8A | 0.2833 | 0.8869 | 0.9021 | 0.022* | |
C9 | −0.0872 (3) | 0.81930 (10) | 0.8791 (2) | 0.0214 (4) | |
H9A | −0.2033 | 0.8177 | 0.8910 | 0.026* | |
C10 | −0.0166 (3) | 0.76412 (11) | 0.8180 (2) | 0.0227 (4) | |
H10A | −0.0727 | 0.7177 | 0.7801 | 0.027* | |
C11 | 0.5754 (3) | 0.54682 (11) | 0.2911 (2) | 0.0210 (4) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.01502 (12) | 0.01346 (12) | 0.01762 (12) | −0.00031 (6) | 0.00926 (9) | −0.00038 (6) |
O1 | 0.0318 (9) | 0.0588 (12) | 0.0659 (13) | 0.0157 (9) | 0.0171 (9) | 0.0309 (10) |
N1 | 0.0191 (8) | 0.0189 (8) | 0.0164 (7) | 0.0038 (6) | 0.0088 (6) | 0.0004 (6) |
N2 | 0.0176 (8) | 0.0172 (8) | 0.0205 (8) | −0.0001 (6) | 0.0101 (6) | −0.0011 (6) |
N3 | 0.0209 (8) | 0.0190 (8) | 0.0181 (8) | 0.0066 (6) | 0.0081 (7) | 0.0010 (6) |
N4 | 0.0203 (8) | 0.0170 (8) | 0.0195 (8) | 0.0025 (6) | 0.0092 (6) | 0.0015 (6) |
N5 | 0.0176 (9) | 0.0289 (11) | 0.0310 (11) | −0.0048 (7) | 0.0084 (8) | −0.0031 (7) |
C1 | 0.0272 (10) | 0.0315 (11) | 0.0202 (10) | 0.0113 (8) | 0.0144 (8) | 0.0028 (8) |
C2 | 0.0199 (9) | 0.0192 (9) | 0.0199 (9) | 0.0027 (7) | 0.0097 (8) | −0.0016 (7) |
C3 | 0.0199 (9) | 0.0188 (9) | 0.0192 (9) | 0.0016 (7) | 0.0094 (8) | −0.0025 (7) |
C4 | 0.0300 (11) | 0.0276 (10) | 0.0221 (9) | 0.0113 (9) | 0.0136 (9) | 0.0003 (8) |
C5 | 0.0181 (9) | 0.0194 (9) | 0.0171 (9) | 0.0011 (7) | 0.0068 (7) | 0.0002 (7) |
C6 | 0.0149 (9) | 0.0180 (9) | 0.0225 (9) | 0.0010 (7) | 0.0060 (7) | 0.0016 (7) |
C7 | 0.0198 (9) | 0.0179 (10) | 0.0194 (9) | 0.0016 (7) | 0.0039 (8) | 0.0003 (8) |
C8 | 0.0199 (9) | 0.0191 (9) | 0.0179 (9) | 0.0023 (7) | 0.0081 (8) | 0.0023 (7) |
C9 | 0.0200 (9) | 0.0186 (9) | 0.0260 (10) | 0.0006 (7) | 0.0092 (8) | 0.0019 (8) |
C10 | 0.0238 (10) | 0.0154 (9) | 0.0267 (10) | 0.0011 (7) | 0.0073 (8) | 0.0010 (8) |
C11 | 0.0159 (9) | 0.0280 (11) | 0.0235 (10) | −0.0061 (9) | 0.0122 (8) | −0.0065 (9) |
Cd1—N5 | 2.329 (2) | C1—C2 | 1.514 (3) |
Cd1—N5i | 2.329 (2) | C1—H1A | 0.9900 |
Cd1—N2 | 2.3276 (15) | C1—H1B | 0.9900 |
Cd1—N2i | 2.3276 (15) | C2—C3 | 1.530 (2) |
Cd1—N4ii | 2.3800 (16) | C2—H2A | 0.9900 |
Cd1—N4iii | 2.3800 (16) | C2—H2B | 0.9900 |
O1—C11 | 1.234 (3) | C3—C4 | 1.516 (3) |
N1—C5 | 1.353 (2) | C3—H3A | 0.9900 |
N1—C7 | 1.375 (2) | C3—H3B | 0.9900 |
N1—C1 | 1.471 (2) | C4—H4A | 0.9900 |
N2—C5 | 1.320 (2) | C4—H4B | 0.9900 |
N2—C6 | 1.375 (2) | C5—H5A | 0.9500 |
N3—C8 | 1.349 (2) | C6—C7 | 1.352 (3) |
N3—C10 | 1.372 (3) | C6—H6A | 0.9500 |
N3—C4 | 1.468 (2) | C7—H7A | 0.9500 |
N4—C8 | 1.320 (2) | C8—H8A | 0.9500 |
N4—C9 | 1.375 (2) | C9—C10 | 1.360 (3) |
N4—Cd1iv | 2.3800 (16) | C9—H9A | 0.9500 |
N5—C11 | 1.130 (3) | C10—H10A | 0.9500 |
N5—Cd1—N5i | 180.0 | C3—C2—H2A | 109.1 |
N5—Cd1—N2 | 88.27 (6) | C1—C2—H2B | 109.1 |
N5i—Cd1—N2 | 91.73 (6) | C3—C2—H2B | 109.1 |
N5—Cd1—N2i | 91.73 (6) | H2A—C2—H2B | 107.9 |
N5i—Cd1—N2i | 88.27 (6) | C4—C3—C2 | 109.55 (15) |
N2—Cd1—N2i | 180.000 (1) | C4—C3—H3A | 109.8 |
N5—Cd1—N4ii | 87.83 (6) | C2—C3—H3A | 109.8 |
N5i—Cd1—N4ii | 92.17 (6) | C4—C3—H3B | 109.8 |
N2—Cd1—N4ii | 89.49 (5) | C2—C3—H3B | 109.8 |
N2i—Cd1—N4ii | 90.51 (5) | H3A—C3—H3B | 108.2 |
N5—Cd1—N4iii | 92.17 (6) | N3—C4—C3 | 113.43 (16) |
N5i—Cd1—N4iii | 87.83 (6) | N3—C4—H4A | 108.9 |
N2—Cd1—N4iii | 90.51 (5) | C3—C4—H4A | 108.9 |
N2i—Cd1—N4iii | 89.49 (5) | N3—C4—H4B | 108.9 |
N4ii—Cd1—N4iii | 180.0 | C3—C4—H4B | 108.9 |
C5—N1—C7 | 107.00 (16) | H4A—C4—H4B | 107.7 |
C5—N1—C1 | 126.94 (16) | N2—C5—N1 | 111.08 (16) |
C7—N1—C1 | 126.05 (16) | N2—C5—H5A | 124.5 |
C5—N2—C6 | 105.81 (15) | N1—C5—H5A | 124.5 |
C5—N2—Cd1 | 128.51 (12) | N2—C6—C7 | 109.82 (16) |
C6—N2—Cd1 | 125.64 (12) | N2—C6—H6A | 125.1 |
C8—N3—C10 | 106.97 (16) | C7—C6—H6A | 125.1 |
C8—N3—C4 | 126.95 (17) | C6—C7—N1 | 106.29 (17) |
C10—N3—C4 | 126.07 (17) | C6—C7—H7A | 126.9 |
C8—N4—C9 | 105.44 (16) | N1—C7—H7A | 126.9 |
C8—N4—Cd1iv | 122.73 (12) | N4—C8—N3 | 111.63 (17) |
C9—N4—Cd1iv | 131.09 (12) | N4—C8—H8A | 124.2 |
C11—N5—Cd1 | 134.36 (15) | N3—C8—H8A | 124.2 |
N1—C1—C2 | 111.94 (15) | C10—C9—N4 | 109.78 (17) |
N1—C1—H1A | 109.2 | C10—C9—H9A | 125.1 |
C2—C1—H1A | 109.2 | N4—C9—H9A | 125.1 |
N1—C1—H1B | 109.2 | C9—C10—N3 | 106.18 (17) |
C2—C1—H1B | 109.2 | C9—C10—H10A | 126.9 |
H1A—C1—H1B | 107.9 | N3—C10—H10A | 126.9 |
C1—C2—C3 | 112.39 (15) | N5—C11—O1 | 178.3 (2) |
C1—C2—H2A | 109.1 | ||
N5—Cd1—N2—C5 | −1.34 (16) | C6—N2—C5—N1 | 0.5 (2) |
N5i—Cd1—N2—C5 | 178.66 (16) | Cd1—N2—C5—N1 | −177.22 (11) |
N4ii—Cd1—N2—C5 | −89.19 (16) | C7—N1—C5—N2 | −0.5 (2) |
N4iii—Cd1—N2—C5 | 90.81 (16) | C1—N1—C5—N2 | 178.33 (17) |
N5—Cd1—N2—C6 | −178.67 (15) | C5—N2—C6—C7 | −0.4 (2) |
N5i—Cd1—N2—C6 | 1.33 (15) | Cd1—N2—C6—C7 | 177.45 (12) |
N4ii—Cd1—N2—C6 | 93.49 (15) | N2—C6—C7—N1 | 0.1 (2) |
N4iii—Cd1—N2—C6 | −86.51 (15) | C5—N1—C7—C6 | 0.2 (2) |
N2—Cd1—N5—C11 | 88.7 (2) | C1—N1—C7—C6 | −178.60 (17) |
N2i—Cd1—N5—C11 | −91.3 (2) | C9—N4—C8—N3 | 0.2 (2) |
N4ii—Cd1—N5—C11 | 178.2 (2) | Cd1iv—N4—C8—N3 | −170.90 (11) |
N4iii—Cd1—N5—C11 | −1.8 (2) | C10—N3—C8—N4 | −0.3 (2) |
C5—N1—C1—C2 | −43.3 (3) | C4—N3—C8—N4 | 178.41 (17) |
C7—N1—C1—C2 | 135.28 (19) | C8—N4—C9—C10 | −0.1 (2) |
N1—C1—C2—C3 | −166.64 (16) | Cd1iv—N4—C9—C10 | 170.02 (13) |
C1—C2—C3—C4 | −173.74 (17) | N4—C9—C10—N3 | −0.1 (2) |
C8—N3—C4—C3 | 84.5 (2) | C8—N3—C10—C9 | 0.2 (2) |
C10—N3—C4—C3 | −97.0 (2) | C4—N3—C10—C9 | −178.49 (17) |
C2—C3—C4—N3 | 177.00 (16) |
Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) −x+1, y−1/2, −z+3/2; (iii) x+1, −y+3/2, z−1/2; (iv) −x+1, y+1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | [Cd(NCO)2(C10H14N4)2] |
Mr | 576.94 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 153 |
a, b, c (Å) | 7.7760 (14), 18.156 (3), 9.0983 (16) |
β (°) | 112.776 (3) |
V (Å3) | 1184.4 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.96 |
Crystal size (mm) | 0.45 × 0.35 × 0.30 |
Data collection | |
Diffractometer | Rigaku Mercury CCD diffractometer |
Absorption correction | Multi-scan (Jacobson, 1998) |
Tmin, Tmax | 0.671, 0.761 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11270, 2163, 2066 |
Rint | 0.018 |
(sin θ/λ)max (Å−1) | 0.602 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.021, 0.056, 1.03 |
No. of reflections | 2163 |
No. of parameters | 161 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.32, −0.37 |
Computer programs: CrystalClear (Rigaku, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
Cd1—N5 | 2.329 (2) | Cd1—N4i | 2.3800 (16) |
Cd1—N2 | 2.3276 (15) | ||
N5—Cd1—N2 | 88.27 (6) | N2—Cd1—N4ii | 90.51 (5) |
N5—Cd1—N4i | 87.83 (6) |
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) x+1, −y+3/2, z−1/2. |
Acknowledgements
This work was supported by the funds of the Civil Aviation University of China (grant No. 08CAUC-S03).
References
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The coordination environment of the CdII atom in the title compound is shown in Fig. 1. Each CdII atom is situated at the center of the symmetry. The coordination geometry of the CdII atom is distorted octahedral, with the metal center coordinated equatorially by four nitrogen atoms from four symmetry-related bimb ligands [Cd1—N2, 2.3276 (15) Å; Cd1—N4 2.3800 (16) Å], and axially by two nitrogen atoms from two cyanate anions [Cd1—N5 2.329 (2) Å]. Each bimb molecule exhibits the all-anti conformation of the tetramethylene linker. The torsion angles N1—C1—C2—C3, C1—C2—C3—C4 and C2—C3—C4—N3 are -166.64 (16), -173.74 (17) and 177.00 (16)°, respectively. The dihedral angle between the two imidazole rings in the ligand planes is 51.15 (8)°. Each CdII atom is bridged by four bimb ligands to form a neutral two-dimensional (4,4) network (Fig. 2). The networks contain square grids (44-membered ring), with a CdII atom at each corner and a bimb molecule at each edge connecting two CdII atoms. The edge lengths are 13.8184 (14) Å, which is obviously longer than the corresponding Cd···Cd separation (9.0819 (2) Å) for [Cd(bimb)2(NCS)2]n in which bimb ligands show the gauche-anti-gauche conformation (Zhang et al., 2008).
The two-dimensional networks parallel to (102) are stacked in an offset fashion along the c direction. In the superposition structure, the networks are arranged in the sequence ···A—B—A—B··· mode (Fig. 3). The cyanate anions are located in the voids.
[Cd(bimb)2(NCS)2]n has an one-dimensional chain structure with double bridging bimb ligands (Zhang et al., 2008). In the present work a two-dimensional cadmium(II) coordination polymer with the (4,4) network was synthesized when cyanate anions were used instead of thiocyanate anions. The factors which play the key role in the construction of the coordination polymers are not very clear. More work is need to extend the knowledge of the coordination polymers.