Acta Cryst. (2008). E64, m578 [ doi:10.1107/S160053680800737X ]
![[mu]](/logos/entities/mu_rmgif.gif)
-1,3-dimethyl-2,6-dioxo-7H-purinato-![[kappa]](/logos/entities/kappa_rmgif.gif)
2N7:N9] hydroxide]The title complex, {[Ni(C7H7N4O2)]OH}n, has been prepared through hydrothermal synthesis. The asymmetric unit contains one [Ni(TH)]+ cation (TH is the theophylline anion) and one hydroxide anion. The Ni2+ ion is coordinated by two N atoms from two neighboring theophylline anions. The alternating linkage of the Ni2+ cation and theophylline anion results in a one-dimensional chain along the [010] direction. Intermolecular O-H
O hydrogen bonds are present n the crystal structure.
A mixture of NiCl2.6H2O (0.50 mmol, 0.12 g), 3,5-dinitrobenzoic acid (0.50 mmol, 0.110 g), theophylline monohydrate (0.50 mmol, 0.09 g), NaOH (0.5 mmol, 0.02 g) and H2O (20 ml) in the mole ratio 1:1:1:1:2 were heated in a Teflon-lined steel autoclave inside a programmable electric furnace at 1433 K for 72 h. After cooling the autoclave to room temperature for 36 h, brown crystals suitable for single-crystal X-ray diffraction were obtained.
H atoms bonded to O atom were located from the difference maps and refined with distance restraints O—H = 0.82 (1) Å. All the remaining H atoms were positioned geometrically, with C—H = 0.93–0.96 Å, and refined as riding, with Uiso(H) = 1.2Ueq(aromatic C) or 1.5Ueq(methyl C).
Data collection: SMART (Bruker, 2001); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PLATON (Spek, 2003).
![[Figure 1]](./at2551fig1thm.gif)
| Fig. 1. Asymmetry structural unit of (I). Displacement ellipsoids for non-H atoms are drawn at the 30% probability level. |
![[Figure 2]](./at2551fig2thm.gif)
| Fig. 2. One-dimensional chain structure of the cations {[Ni(TH)]+}n. Hydrogen atoms are omitted for clarity. |
| [Ni(C7H7N4O2)]OH | F000 = 520 |
| Mr = 254.88 | Dx = 1.886 Mg m−3 |
| Monoclinic, P21/c | Mo Kα radiation λ = 0.71073 Å |
| Hall symbol: -P 2ybc | Cell parameters from 1720 reflections |
| a = 11.399 (3) Å | θ = 2.2–28.0º |
| b = 11.533 (2) Å | µ = 2.15 mm−1 |
| c = 6.9807 (15) Å | T = 298 (2) K |
| β = 101.993 (3)º | Block, brown |
| V = 897.7 (3) Å3 | 0.48 × 0.24 × 0.08 mm |
| Z = 4 |
| Bruker SMART APEX CCD area-detector diffractometer | 1753 independent reflections |
| Radiation source: fine-focus sealed tube | 1592 reflections with I > 2σ(I) |
| Monochromator: graphite | Rint = 0.024 |
| T = 298(2) K | θmax = 26.0º |
| ω scans | θmin = 1.8º |
| Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | h = −14→5 |
| Tmin = 0.425, Tmax = 0.847 | k = −13→14 |
| 4701 measured reflections | l = −8→8 |
| 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)] = 0.028 | H atoms treated by a mixture of independent and constrained refinement |
| wR(F2) = 0.078 | w = 1/[σ2(Fo2) + (0.048P)2 + 0.1385P] where P = (Fo2 + 2Fc2)/3 |
| S = 1.07 | (Δ/σ)max = 0.001 |
| 1753 reflections | Δρmax = 0.36 e Å−3 |
| 142 parameters | Δρmin = −0.43 e Å−3 |
| 7 restraints | Extinction correction: none |
| Primary atom site location: structure-invariant direct methods |
| [Ni(C7H7N4O2)]OH | V = 897.7 (3) Å3 |
| Mr = 254.88 | Z = 4 |
| Monoclinic, P21/c | Mo Kα |
| a = 11.399 (3) Å | µ = 2.15 mm−1 |
| b = 11.533 (2) Å | T = 298 (2) K |
| c = 6.9807 (15) Å | 0.48 × 0.24 × 0.08 mm |
| β = 101.993 (3)º |
| Bruker SMART APEX CCD area-detector diffractometer | 1753 independent reflections |
| Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | 1592 reflections with I > 2σ(I) |
| Tmin = 0.425, Tmax = 0.847 | Rint = 0.024 |
| 4701 measured reflections |
| R[F2 > 2σ(F2)] = 0.028 | 7 restraints |
| wR(F2) = 0.078 | H atoms treated by a mixture of independent and constrained refinement |
| S = 1.07 | Δρmax = 0.36 e Å−3 |
| 1753 reflections | Δρmin = −0.43 e Å−3 |
| 142 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 | ||
| Ni1 | 0.48633 (3) | 0.53369 (2) | 0.24668 (4) | 0.03643 (14) | |
| O1 | 0.2600 (2) | 0.03105 (12) | 0.0185 (3) | 0.0546 (5) | |
| O2 | 0.04285 (16) | 0.36076 (15) | −0.1653 (3) | 0.0568 (4) | |
| O3 | 0.2120 (4) | 0.7950 (3) | 0.9081 (7) | 0.1392 (14) | |
| H3 | 0.227 (5) | 0.8648 (16) | 0.931 (7) | 0.135 (6)* | |
| N1 | 0.44301 (17) | 0.37995 (14) | 0.1875 (3) | 0.0365 (4) | |
| N2 | 0.46418 (17) | 0.18588 (15) | 0.1998 (3) | 0.0367 (4) | |
| N3 | 0.15129 (17) | 0.19704 (15) | −0.0707 (3) | 0.0399 (4) | |
| N4 | 0.23455 (17) | 0.38436 (14) | 0.0017 (2) | 0.0381 (4) | |
| C1 | 0.51491 (19) | 0.28771 (17) | 0.2480 (3) | 0.0368 (5) | |
| H1 | 0.5935 | 0.2955 | 0.3177 | 0.044* | |
| C2 | 0.35017 (19) | 0.21287 (15) | 0.0998 (3) | 0.0329 (4) | |
| C3 | 0.2555 (2) | 0.13741 (16) | 0.0164 (3) | 0.0377 (5) | |
| C4 | 0.1381 (2) | 0.31716 (19) | −0.0830 (3) | 0.0393 (5) | |
| C5 | 0.33876 (18) | 0.33133 (15) | 0.0931 (3) | 0.0318 (4) | |
| C6 | 0.0440 (2) | 0.1291 (2) | −0.1542 (4) | 0.0554 (6) | |
| H6A | −0.0174 | 0.1442 | −0.0819 | 0.083* | |
| H6B | 0.0635 | 0.0481 | −0.1466 | 0.083* | |
| H6C | 0.0157 | 0.1507 | −0.2887 | 0.083* | |
| C7 | 0.2229 (3) | 0.5112 (2) | −0.0110 (4) | 0.0520 (6) | |
| H7A | 0.2696 | 0.5456 | 0.1054 | 0.078* | |
| H7B | 0.1402 | 0.5323 | −0.0236 | 0.078* | |
| H7C | 0.2513 | 0.5384 | −0.1232 | 0.078* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Ni1 | 0.0411 (2) | 0.01831 (18) | 0.0477 (2) | −0.00491 (9) | 0.00408 (13) | −0.00290 (8) |
| O1 | 0.0644 (13) | 0.0267 (8) | 0.0696 (11) | −0.0096 (7) | 0.0068 (10) | −0.0035 (6) |
| O2 | 0.0416 (9) | 0.0613 (11) | 0.0608 (10) | 0.0094 (8) | −0.0050 (8) | 0.0053 (8) |
| O3 | 0.118 (3) | 0.0735 (17) | 0.203 (4) | −0.0072 (19) | −0.019 (3) | 0.001 (2) |
| N1 | 0.0405 (10) | 0.0246 (7) | 0.0428 (9) | −0.0015 (7) | 0.0052 (8) | −0.0014 (7) |
| N2 | 0.0397 (10) | 0.0244 (8) | 0.0437 (9) | 0.0021 (7) | 0.0036 (8) | 0.0010 (7) |
| N3 | 0.0380 (10) | 0.0387 (9) | 0.0406 (9) | −0.0066 (8) | 0.0027 (8) | −0.0010 (7) |
| N4 | 0.0413 (10) | 0.0291 (8) | 0.0419 (9) | 0.0054 (7) | 0.0040 (8) | 0.0035 (7) |
| C1 | 0.0370 (12) | 0.0269 (12) | 0.0438 (12) | 0.0005 (8) | 0.0022 (10) | 0.0003 (7) |
| C2 | 0.0375 (11) | 0.0240 (9) | 0.0363 (10) | −0.0006 (8) | 0.0055 (8) | −0.0002 (7) |
| C3 | 0.0473 (13) | 0.0286 (10) | 0.0381 (10) | −0.0049 (8) | 0.0107 (9) | −0.0007 (7) |
| C4 | 0.0409 (12) | 0.0409 (11) | 0.0358 (10) | 0.0024 (9) | 0.0067 (9) | 0.0003 (9) |
| C5 | 0.0383 (11) | 0.0230 (8) | 0.0339 (9) | 0.0022 (8) | 0.0072 (8) | 0.0006 (7) |
| C6 | 0.0480 (14) | 0.0587 (15) | 0.0562 (14) | −0.0190 (12) | 0.0033 (12) | −0.0054 (11) |
| C7 | 0.0574 (16) | 0.0295 (10) | 0.0639 (15) | 0.0110 (11) | 0.0008 (12) | 0.0038 (10) |
| Ni1—N2i | 1.8577 (17) | N4—C5 | 1.370 (3) |
| Ni1—N1 | 1.8636 (17) | N4—C4 | 1.374 (3) |
| O1—C3 | 1.228 (2) | N4—C7 | 1.469 (3) |
| O2—C4 | 1.226 (3) | C1—H1 | 0.9300 |
| O3—H3 | 0.832 (11) | C2—C5 | 1.372 (3) |
| N1—C5 | 1.355 (3) | C2—C3 | 1.414 (3) |
| N1—C1 | 1.356 (3) | C6—H6A | 0.9600 |
| N2—C1 | 1.321 (3) | C6—H6B | 0.9600 |
| N2—C2 | 1.377 (3) | C6—H6C | 0.9600 |
| N2—Ni1ii | 1.8577 (17) | C7—H7A | 0.9600 |
| N3—C4 | 1.394 (3) | C7—H7B | 0.9600 |
| N3—C3 | 1.398 (3) | C7—H7C | 0.9600 |
| N3—C6 | 1.467 (3) | ||
| N2i—Ni1—N1 | 177.25 (8) | O1—C3—C2 | 125.7 (2) |
| C5—N1—C1 | 103.84 (16) | N3—C3—C2 | 112.53 (17) |
| C5—N1—Ni1 | 131.82 (14) | O2—C4—N4 | 121.4 (2) |
| C1—N1—Ni1 | 124.22 (14) | O2—C4—N3 | 120.7 (2) |
| C1—N2—C2 | 104.20 (15) | N4—C4—N3 | 117.9 (2) |
| C1—N2—Ni1ii | 133.63 (15) | N1—C5—N4 | 129.03 (17) |
| C2—N2—Ni1ii | 122.05 (14) | N1—C5—C2 | 109.16 (18) |
| C4—N3—C3 | 125.93 (19) | N4—C5—C2 | 121.81 (19) |
| C4—N3—C6 | 115.8 (2) | N3—C6—H6A | 109.5 |
| C3—N3—C6 | 118.24 (19) | N3—C6—H6B | 109.5 |
| C5—N4—C4 | 119.16 (17) | H6A—C6—H6B | 109.5 |
| C5—N4—C7 | 122.08 (19) | N3—C6—H6C | 109.5 |
| C4—N4—C7 | 118.75 (19) | H6A—C6—H6C | 109.5 |
| N2—C1—N1 | 114.44 (18) | H6B—C6—H6C | 109.5 |
| N2—C1—H1 | 122.8 | N4—C7—H7A | 109.5 |
| N1—C1—H1 | 122.8 | N4—C7—H7B | 109.5 |
| C5—C2—N2 | 108.36 (18) | H7A—C7—H7B | 109.5 |
| C5—C2—C3 | 122.7 (2) | N4—C7—H7C | 109.5 |
| N2—C2—C3 | 128.95 (17) | H7A—C7—H7C | 109.5 |
| O1—C3—N3 | 121.7 (2) | H7B—C7—H7C | 109.5 |
| Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| O3—H3···O1iii | 0.832 (11) | 2.023 (12) | 2.851 (3) | 173 (5) |
| Symmetry codes: (iii) x, y+1, z+1. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| O3—H3···O1i | 0.832 (11) | 2.023 (12) | 2.851 (3) | 173 (5) |
| Symmetry codes: (i) x, y+1, z+1. |
Bruker (2001). SAINT-Plus (Version 6.45) and SMART (Version 5.628). Bruker AXS Inc., Madison, Wisconsin, USA.
Horikoshi, R. & Mochida, T. (2006). Coord. Chem. Rev. 250, 2595–2609.
Robin, A. Y. & Fromm, K. M. (2003). Coord. Chem. Rev. 250, 2127–2157.
Sheldrick, G. M. (2001). SADABS. Version 2.10. Bruker AXS Inc., Madison, Wisconsin, USA.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13.
The rational design, synthesis and characterization of coordination polymers construct from transition metal ions, especially the first-row transition metal, and various organic ligands linked with covalent bonds have still been actively researched as one of highly topical research areas aiming to obtain fascinating structures as well as special properties such as magnetism, catalysis, molecular recognition, ion exchange, nonlinear optical behavior and electrical conductivity (Robin & Fromm, 2003; Horikoshi & Mochida, 2006). Herein we present a one-dimensional,linear transition metal complexes, namely {[Ni(TH)]OH}n(TH = theophylline anion), (I).
Each asymmetry unit of the title compound (I) consists of one [Ni(TH)]+ cation and one isolated hydroxyl anion (Fig.1). Ni2+ adopts a two-coordinate coordination mode and coordinated by two nitrogen atoms from two neighboring theophylline anions with average Ni—N length 1.861° and N—Ni—N angle 177.25° (Table 1), respectively. The short Ni—N distances in the compound are caused by the low coordination numbers and highly positive charges. The alternate linkers of Ni2+ ion and theophylline anion within which two adjacent anions are in the trans-position finally give rise to a one-dimensional chain (Fig.2). To best of our knowledge, the title complex is firstly reported. We found 3,5-dinitrobenzoic acid takes an key role in controlling the formation of the title compound. If 3,5-Ddinitrobenzoic acid was not added into the reaction system, the compound can't be obtained. Moreover, we also found basic medium NaOH must be added into the reaction system. Otherwise these compounds can't be prepared. We think that 3,5-dinitrobenzoic acid here acts as a reaction template. Additionally, the effect of the basic medium (NaOH) made NH group of theophylline deprotonate leading to the formation of a monoanionic bidentate ligand.