Abstract
C16H18N4O8, monoclinic, C2/m (no. 12), a = 14.517(4) Å, b = 18.006(7) Å, c = 6.916(3) Å, β = 116.97(3)°, V = 1611.2(11) Å3, Z = 4, Rgt(F) = 0.0497, wRref(F2) = 0.1387, T = 296(2) K.
The salt-type title crystal structure is shown in the figure. Tables 1 and 2 contain details of the measurement method and a list of the atoms including atomic coordinates and displacement parameters.
Data collection and handling.
| Crystal: | Colourless block |
| Size: | 0.15 × 0.15 × 0.10 mm |
| Wavelength: | Mo Kα radiation (0.71073 Å) |
| μ: | 0.13 mm−1 |
| Diffractometer, scan mode: | APEX CCD, f and w scans |
| 2θmax, completeness: | 28.4°, >99% |
| N(hkl)measured, N(hkl)unique, Rint: | 7546, 2068, 0.041 |
| Criterion for Iobs, N(hkl)gt: | Iobs > 2 σ(Iobs), 1326 |
| N(param)refined: | 144 |
| Programs: | Bruker [7], SHELX [8], [9] |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2).
| Atom | x | y | z | Uiso*/Ueq |
|---|---|---|---|---|
| H2Oa | 0.874(3) | 0.0239(9) | 0.976(9) | 0.10(3)* |
| O1Aa | 0.8488(6) | 0.0628(4) | 1.0003(8) | 0.083(3) |
| O1Ba | 0.8873(6) | 0.0694(3) | 0.9735(9) | 0.077(3) |
| C1 | 0.80234(18) | 0.09111(12) | 0.8080(3) | 0.0412(6) |
| C2 | 0.75693(14) | 0.03864(10) | 0.6152(3) | 0.0277(4) |
| C3 | 0.71038(14) | 0.07486(10) | 0.4163(3) | 0.0252(4) |
| H1 | 0.7098 | 0.1265 | 0.4167 | 0.030* |
| C4 | 0.66478(13) | 0.03908(10) | 0.2172(3) | 0.0238(4) |
| C5 | 0.62023(15) | 0.09157(11) | 0.0252(3) | 0.0286(4) |
| C6 | 0.5000 | 0.38010(16) | 0.5000 | 0.0365(7) |
| H6 | 0.4656 | 0.4122 | 0.3765 | 0.044* |
| C7 | 0.36991(16) | 0.28844(13) | 0.3321(3) | 0.0398(5) |
| H7A | 0.3436 | 0.3207 | 0.2061 | 0.048* |
| H7B | 0.3162 | 0.2572 | 0.3561 | 0.048* |
| C8 | 0.47141(18) | 0.28868(13) | 0.7120(3) | 0.0389(5) |
| H8A | 0.5069 | 0.3216 | 0.8423 | 0.047* |
| H8B | 0.4214 | 0.2583 | 0.7378 | 0.047* |
| C9 | 0.5000 | 0.19030(15) | 0.5000 | 0.0332(7) |
| H9 | 0.4499 | 0.1606 | 0.5217 | 0.040* |
| N1 | 0.42276(13) | 0.33437(10) | 0.5225(3) | 0.0357(4) |
| N2 | 0.55084(13) | 0.23931(9) | 0.6922(2) | 0.0327(4) |
| H2 | 0.5821 | 0.2104 | 0.8100 | 0.039* |
| O2 | 0.77891(14) | 0.15570(9) | 0.7872(2) | 0.0505(5) |
| O3 | 0.62778(12) | 0.15884(8) | 0.0596(2) | 0.0398(4) |
| O4 | 0.57607(12) | 0.06621(9) | −0.1684(2) | 0.0440(4) |
| H1Oa | 0.579(3) | 0.014(3) | −0.176(6) | 0.053* |
aOccupancy: 0.5.
Source of material
All reagents and solvents were purchased from commercial sources and used as received. An aqueous solution (5 mL) of hexamethylenetetramine (70 mg, 0.5 mmol) and an ethanolic solution (5 mL) of 1,2,4,5-benzene tetracarboxylic acid (130 mg, 0.5 mmol) were mixed, and the solution was allowed to stand at room temperature. Colorless plate crystals were obtained after three days (yield 40 mg, 20%).
Experimental details
H atoms bound to C atoms were placed in calculated positions and refined as riding on their parent atoms, with C—H = 0.93 Å (aromatic), C—H = 0.96 Å (methylene), and with Uiso(H) = 1.5 Ueq(C) for methyl H atoms and 1.2 Ueq(C) for all other H atoms. The H atoms bound to N and O atoms were found from the Fourier difference map.
Comment
Multicarboxylates are widely used as building blocks for the construction of supramolecular structures, not only because they have versatile coordination modes to metal ions, but also because they are hydrogen bonding acceptors and donors [1], [2], [3]. Meanwhile, hexamethylenetetramine (hmt), having four N atoms, also can be involved in hydrogen bonding to generate diamond-type supramolecular networks [4], [5]. With this in mind, we have become interested in the preparation of supramolecular structures based on the multicarboxylates and hexamethylenetetramine. Herein, we report the salt-type crystal structure [6] based on 1,2,4,5-benzene tetracarboxylic acid (H4btc) and hexamethylenetetramine, [H2hmt][H2btc].
The asymmetric unit of the title compound consists of one half of a [H2hmt]2+ cation and one half of a [H2btc]2− anion, resulting in a 1:1 salt. In the structure, the two protons of the former 1,2,4,5-benzene tetracarboxylic acid were transferred to two N atoms of hexamethylenetetramine. Each [H2hmt]2+ cation is hydrogen-bonded with two adjacent [H2btc]2− anions, and each [H2btc]2− anion is also hydrogen-bonded with two adjacent [H2hmt]2+ cations to form [2 + 2] dimers through four medium strong N2-H2⋅⋅⋅O3 hydrogen bonds (N2-H2⋅⋅⋅O3 = 2.689(2) Å).
Acknowledgements
This work was supported by the National Key Research and Development Program of China (No. 2017YFD0501406), the National Nature Foundation of China [No. 21461011 and 31560712], the Natural Science Foundation of Jiangxi Province [No. 20112BBF60024], and the Foundation of Jiangxi Educational Committee (GJJ170245, GJJ170257£©).
References
Cook, T. R.; Zheng, Y.-R.; Stang, P. J.: Metal–organic frameworks and self–assembled supramolecular coordination complexes: comparing and contrasting the design, synthesis, and functionality of metal–organic materials. Chem. Rev. 113 (2013) 734–777.10.1021/cr3002824Search in Google Scholar PubMed PubMed Central
O’Keeffe, M.; Yaghi, O. M.: Deconstructing the crystal structures of metal organic frameworks and related materials into their underlying nets. Chem. Rev. 112 (2012) 675–702.10.1021/cr200205jSearch in Google Scholar PubMed
Zhao, S.-Q.; Gu, J.-Z.: Syntheses, crystal structures and magnetic properties of Mn(II) and Ni(II) dinuclear coordination compounds constructed from biphenyl-2,4,4′-tricarboxylate and phenanthroline. Chin. J. Inorg. Chem. 32 (2016) 1611–1618.Search in Google Scholar
Hazra, S.; Biswas, S.; Kirillov, A. M.; Ghosh, A.: Nickel(II) complexes self-assembled from hexamethylenetetramine and isomeric nitrobenzoates: structural diversity and supramolecular features. Polyhedron 79 (2014) 66–71.10.1016/j.poly.2014.04.038Search in Google Scholar
Kirillov, A. M.: Hexamethylenetetramine: an old new building block for design of coordination polymers. Coord. Chem. Rev. 255 (2011) 1603–1622.10.1016/j.ccr.2011.01.023Search in Google Scholar
Kole, G. K.; Tan, G. K.; Vittal, J. J.: Crystal engineering studies on the salts of trans-4,4′-stilbenedicarboxylic acid in the context of solid state [2 + 2] cycloaddition reaction. CrystEngComm 13 (2011) 3138–3145.10.1039/C0CE00224KSearch in Google Scholar
BRUKER. SAINT, APEX2 and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA, (2009).Search in Google Scholar
Sheldrick, G. M.: SHELXT − Integrated space-group andcrystal-structure determination. Acta Crystallogr. A71 (2015)3–8.10.1107/S2053273314026370Search in Google Scholar
Sheldrick, G. M.: Crystal structure refinement with SHELXL. Acta Crystallogr. C71 (2015) 3–8.10.1107/S2053229614024218Search in Google Scholar PubMed PubMed Central
©2018 Xiao Wei et al., published by De Gruyter, Berlin/Boston
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