research communications
κN)(N,N-dimethylformamide-κO)(μ3-pyridine-3,5-dicarboxylato-κ3N:O3:O5)copper(II)]
of poly[(4-aminopyridine-aInstitute of Inorganic Materials, School of Materials Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China
*Correspondence e-mail: hanlei@nbu.edu.cn
The title compound, [Cu(C7H3NO4)(C5H6N2)(C3H7NO]n, is an amino-functionalized chiral metal–organic framework with (10,3)-a topology. It has been constructed via the assembly of the achiral triconnected pyridine-3,5-dicarboxylate (3,5-PDC) building block and a triconnected CuII atom. Each CuII ion is coordinated by two O atoms and one N atom, respectively, of three crystallographically independent 3,5-PDC ligands. The square-pyramidal (CuN2O3) coordination geometry of the CuII ion is completed by an N atom of a terminal 4-aminopyridine (4-APY) ligand and the O atom of a terminal N,N-dimethylformamide (DMF) ligand to give a triconnected `T'-shaped secondary building unit, which becomes trigonal in the resulting (10,3)-a topology. In the three-dimensional structure, weak N—H⋯O hydrogen bonds are observed in which the donor N—H groups are provided by the 4-APY ligands and the acceptor O atoms are provided by the non-coordinating carboxylate O atoms of the 3,5-PDC ligands.
CCDC reference: 1456364
1. Chemical context
Research on metal–organic frameworks (MOFs) has attracted much attention in recent years not only for their great potential applications, such as in gas storage, separation, fluorescence and magnetism, but also for their intriguing topologies and structural diversity (Allendorf et al., 2009). Of special interest is the rational design and synthesis of chiral networks, which offer great potential in non-linear optics, asymmetric catalysis, and chiral separation (Evans & Lin, 2002; Zhang & Xiong, 2012). Therefore, a logical target for synthesis would be a default structure that possesses The (10,3)-a network meets these requirements since it is mutually chiral and regarded as the default three-dimensional structure for the assembly of triconnected building blocks (Eubank et al., 2005; Han et al., 2013a).
On the other hand, amino-functionalized porous metal-organic frameworks have also attracted much attention. Recent research on amino-functionalized MOFs revealed that they have high CO2 at lower pressure due to the potential interaction between amino groups and CO2 (Couck et al., 2009). Amino-functionalized MOFs can also act as reaction active sites for the post-synthesis modification of metal-organic frameworks (Shultz et al., 2011).
As a continuation of our group research on the assembly of amino-functionalized chiral metal–organic frameworks (Han et al., 2011, 2013b; Pan et al., 2014), we herein report the preparation and of Cu(3,5-PDC)(4-APY)(DMF), (3,5-PDC = pyridine-3,5-dicarboxylate, 4-APY = 4-aminopyridine, DMF = N,N-dimethylformamide), which was constructed via the assembly of the achiral triconnected building block pyridine-3,5-dicarboxylate (3,5- PDC) and a triconnected CuII atom, CuN(CO2)2, synthesized in situ. The title compound is an interesting example of an amino-functionalized chiral metal-organic framework with (10,3)-a topology assembled from achiral ligands. This amino-functionalized chiral framework can be used for depositing small gold nanoparticles using a solution-based adsorption/reduction preparation method, and offer myriad opportunities for chiral catalysis.
2. Structural commentary
The II ion, one 3,5-PDC anion, one 4-apy molecule and one DMF molecule. As shown in Fig. 1, each CuII ion adopts a square-pyramidal (CuN2O3) coordination geometry. In the equatorial plane, the CuII ion is coordinated by two oxygen atoms and one nitrogen atom, respectively, of three crystallographically independent 3,5-PDC ligands, and one nitrogen atom of a terminal 4-APY ligand. The oxygen atom of a terminal DMF molecule is bonded to the CuII ion in the axial position to complete the square-pyramidal coordination geometry. The bond lengths and bond angles around the CuII ion are in good agreement with similar structures (Eubank et al., 2005; Lu et al., 2006). The axial Cu—ODMF bond length [2.396 (4) Å] is longer than the equatorial Cu—Ocarboxylate and Cu—N4-APY bonds due to the Jahn–Teller effect of the Cu2+ atom.
of the title compound, Cu(3,5-PDC)(4-APY)(DMF), contains one CuThe three-dimensional structure of the title compound viewed along the a axis is shown in Fig. 2. To analyse the topology, the square-pyramidal coordination geometry of copper can act as a `T'-shaped triconnected secondary building unit (Fig. 2), which becomes trigonal in the resulting topology. At the same time, 3,5-PDC acts as another triconnected node since it possesses two deprotonated carboxylic acid coordinating sites, and a third, neutral aromatic nitrogen coordinating site. As a result, the desired triconnected (10,3)-a network is obtained, as shown in Fig. 3. The terminally coordinated 4-APY and DMF ligands are oriented to the interior of the channels and thus prevent self-interpenetration. The (10,3)-a topology leads to an enantiopure network of the title compound (Eubank et al., 2005; Han et al., 2013a), despite being formed solely from achiral molecular units.
3. Supramolecular features
By introducing 4-aminopyridine as co-ligand, the amino-functionalized chiral metal-organic framework was successfully designed and synthesized. Additionally, the –NH2 group of the 4-APY ligand can act as the donor N—H groups to form hydrogen bonds (Han et al., 2011). In the three-dimensional structure of the title compound, weak N—H⋯O hydrogen bonds are observed (Table 1) in which the acceptors are provided by the non-coordinating oxygen atoms of the carboxylate groups of the 3,5-PDC ligands.
4. Synthesis and crystallization
The title compound was prepared by a solvothermal method. A mixture of pyridine-3,5-dicarboxylic acid (0.0339 g, 0.2 mmol), 4-aminopyridine (0.0098 g, 0.10 mmol) and Cu(NO3)2·3H2O (0.0484 g, 0.20 mmol) in 6 ml DMF solution was stirred at room temperature for 30 minutes, and subsequently sealed in a 25 ml Teflon-lined stainless steel reactor. The reactor was heated at 363 K for 3 d. A crop of blue, block-shaped single crystals of the title compound was obtained after cooling the solution to room temperature. The yield was approximately 70% based on Cu salt.
5. details
Crystal data, data collection and structure . All H atoms were placed in geometrically idealized positions and refined in a riding-model approximation on their parent atoms, with Uiso(H) = 1.2Ueq(C) (aromatic) and 1.5Ueq(C) (methyl) with C—H = 0.93 Å (aromatic) and 0.96 Å (methyl), and Uiso(H) = 1.2Ueq(N) with N—H = 0.86 Å.
details are summarized in Table 2Supporting information
CCDC reference: 1456364
https://doi.org/10.1107/S205698901600342X/lh5806sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901600342X/lh5806Isup2.hkl
Data collection: APEX2 (Bruker, 2014); cell
SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).[Cu(C7H3NO4)(C5H6N2)(C3H7NO)] | Dx = 1.586 Mg m−3 |
Mr = 395.86 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 2974 reflections |
a = 8.3365 (17) Å | θ = 3.1–27.5° |
b = 10.453 (2) Å | µ = 1.35 mm−1 |
c = 19.030 (4) Å | T = 293 K |
V = 1658.2 (6) Å3 | Block, blue |
Z = 4 | 0.24 × 0.20 × 0.19 mm |
F(000) = 812 |
Bruker APEXII DUO CCD diffractometer | 3799 independent reflections |
Radiation source: fine-focus sealed tube | 2926 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.051 |
ω–scans | θmax = 27.5°, θmin = 3.1° |
Absorption correction: analytical [based on measured indexed crystal faces using SHELXL2014 (Sheldrick, 2015b)] | h = −10→10 |
Tmin = 0.716, Tmax = 0.773 | k = −13→13 |
16376 measured reflections | l = −24→22 |
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)] = 0.039 | H-atom parameters constrained |
wR(F2) = 0.132 | w = 1/[σ2(Fo2) + (0.0573P)2 + 1.9518P] where P = (Fo2 + 2Fc2)/3 |
S = 1.15 | (Δ/σ)max = 0.013 |
3799 reflections | Δρmax = 0.79 e Å−3 |
226 parameters | Δρmin = −1.17 e Å−3 |
0 restraints | Absolute structure: Flack (1983), 1619 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.00 (2) |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 | −0.23946 (7) | 0.10503 (5) | 0.62338 (2) | 0.02797 (16) | |
O1 | 0.0648 (5) | 0.3766 (4) | 0.83488 (17) | 0.0497 (10) | |
O2 | 0.2102 (4) | 0.5278 (3) | 0.78331 (16) | 0.0348 (8) | |
O3 | 0.3228 (5) | 0.4977 (4) | 0.5253 (2) | 0.0498 (11) | |
O4 | 0.2342 (5) | 0.3222 (3) | 0.47057 (14) | 0.0337 (7) | |
O5 | −0.4048 (6) | 0.2700 (4) | 0.6723 (3) | 0.0605 (12) | |
N1 | −0.0413 (5) | 0.2178 (4) | 0.63928 (18) | 0.0284 (8) | |
N2 | −0.4300 (5) | −0.0057 (4) | 0.6043 (2) | 0.0347 (10) | |
N3 | −0.8209 (6) | −0.2450 (6) | 0.5764 (3) | 0.0705 (18) | |
H3A | −0.8050 | −0.3239 | 0.5657 | 0.085* | |
H3B | −0.9170 | −0.2170 | 0.5822 | 0.085* | |
N4 | −0.3401 (8) | 0.4804 (5) | 0.6705 (3) | 0.0625 (17) | |
C1 | 0.2489 (6) | 0.3962 (4) | 0.5239 (2) | 0.0315 (9) | |
C2 | 0.0476 (6) | 0.2565 (4) | 0.5840 (2) | 0.0291 (10) | |
H2A | 0.0301 | 0.2180 | 0.5406 | 0.035* | |
C3 | 0.1883 (6) | 0.4086 (5) | 0.6536 (2) | 0.0297 (10) | |
H3C | 0.2624 | 0.4745 | 0.6582 | 0.036* | |
C4 | 0.1634 (6) | 0.3505 (4) | 0.5889 (2) | 0.0267 (9) | |
C5 | −0.0125 (6) | 0.2721 (5) | 0.7013 (2) | 0.0310 (10) | |
H5A | −0.0716 | 0.2450 | 0.7400 | 0.037* | |
C6 | 0.1011 (6) | 0.3670 (4) | 0.7112 (2) | 0.0278 (10) | |
C7 | 0.1250 (6) | 0.4263 (5) | 0.7828 (2) | 0.0316 (11) | |
C8 | −0.5796 (7) | 0.0376 (5) | 0.6086 (3) | 0.0448 (13) | |
H8A | −0.5945 | 0.1240 | 0.6183 | 0.054* | |
C9 | −0.7126 (7) | −0.0366 (5) | 0.5999 (3) | 0.0502 (15) | |
H9A | −0.8141 | −0.0008 | 0.6045 | 0.060* | |
C10 | −0.6962 (7) | −0.1657 (6) | 0.5839 (3) | 0.0458 (14) | |
C11 | −0.5405 (7) | −0.2092 (5) | 0.5747 (3) | 0.0521 (15) | |
H11A | −0.5225 | −0.2933 | 0.5608 | 0.062* | |
C12 | −0.4130 (7) | −0.1294 (5) | 0.5860 (3) | 0.0454 (13) | |
H12A | −0.3100 | −0.1621 | 0.5808 | 0.055* | |
C13 | −0.3972 (9) | 0.3755 (6) | 0.7001 (4) | 0.0610 (17) | |
H13A | −0.4348 | 0.3824 | 0.7460 | 0.073* | |
C14 | −0.330 (2) | 0.5962 (7) | 0.7100 (5) | 0.164 (7) | |
H14A | −0.3715 | 0.5821 | 0.7564 | 0.246* | |
H14B | −0.3920 | 0.6616 | 0.6872 | 0.246* | |
H14C | −0.2201 | 0.6229 | 0.7130 | 0.246* | |
C15 | −0.2832 (11) | 0.4792 (7) | 0.5991 (4) | 0.076 (2) | |
H15A | −0.2989 | 0.3957 | 0.5793 | 0.114* | |
H15B | −0.1711 | 0.5001 | 0.5983 | 0.114* | |
H15C | −0.3418 | 0.5411 | 0.5720 | 0.114* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0355 (3) | 0.0291 (3) | 0.0193 (2) | −0.0032 (3) | −0.0035 (2) | 0.0024 (2) |
O1 | 0.054 (2) | 0.074 (3) | 0.0212 (16) | −0.017 (2) | 0.0063 (16) | −0.0070 (18) |
O2 | 0.044 (2) | 0.0349 (16) | 0.0254 (15) | −0.0002 (16) | −0.0046 (15) | −0.0092 (14) |
O3 | 0.064 (3) | 0.049 (2) | 0.0366 (19) | −0.0273 (19) | 0.0124 (19) | −0.0012 (17) |
O4 | 0.051 (2) | 0.0313 (15) | 0.0188 (12) | 0.0015 (17) | 0.0056 (16) | 0.0016 (12) |
O5 | 0.058 (3) | 0.047 (2) | 0.077 (3) | −0.005 (2) | 0.005 (2) | −0.022 (2) |
N1 | 0.033 (2) | 0.034 (2) | 0.0183 (17) | −0.0005 (17) | 0.0000 (15) | 0.0018 (16) |
N2 | 0.033 (2) | 0.038 (2) | 0.033 (2) | 0.0032 (17) | −0.0033 (18) | −0.0002 (17) |
N3 | 0.038 (3) | 0.061 (3) | 0.113 (5) | −0.018 (3) | 0.012 (3) | −0.036 (3) |
N4 | 0.101 (5) | 0.037 (3) | 0.050 (3) | 0.003 (3) | −0.014 (3) | −0.001 (2) |
C1 | 0.035 (2) | 0.036 (2) | 0.0233 (17) | −0.001 (3) | 0.001 (2) | 0.0029 (18) |
C2 | 0.036 (3) | 0.034 (2) | 0.0174 (19) | −0.002 (2) | 0.0006 (18) | −0.0017 (19) |
C3 | 0.031 (2) | 0.032 (2) | 0.026 (2) | −0.001 (2) | 0.0001 (17) | −0.002 (2) |
C4 | 0.031 (2) | 0.027 (2) | 0.022 (2) | 0.0041 (18) | 0.0027 (18) | −0.0020 (18) |
C5 | 0.038 (3) | 0.038 (3) | 0.0168 (19) | −0.002 (2) | −0.0006 (19) | 0.0007 (19) |
C6 | 0.031 (2) | 0.033 (2) | 0.0201 (19) | 0.0017 (19) | −0.0031 (17) | 0.0007 (18) |
C7 | 0.025 (2) | 0.046 (3) | 0.024 (2) | 0.001 (2) | 0.0020 (18) | −0.006 (2) |
C8 | 0.047 (3) | 0.032 (3) | 0.056 (4) | −0.002 (2) | −0.003 (3) | −0.007 (3) |
C9 | 0.036 (3) | 0.044 (3) | 0.070 (4) | 0.004 (3) | 0.000 (3) | −0.014 (3) |
C10 | 0.036 (3) | 0.046 (3) | 0.056 (3) | −0.005 (2) | 0.004 (2) | −0.015 (3) |
C11 | 0.047 (3) | 0.038 (3) | 0.071 (4) | −0.001 (3) | −0.003 (3) | −0.016 (3) |
C12 | 0.038 (3) | 0.033 (3) | 0.065 (4) | −0.004 (2) | −0.002 (3) | −0.016 (3) |
C13 | 0.069 (4) | 0.057 (4) | 0.057 (4) | 0.004 (3) | −0.005 (3) | −0.011 (3) |
C14 | 0.37 (2) | 0.047 (4) | 0.079 (6) | −0.036 (8) | −0.019 (9) | −0.014 (4) |
C15 | 0.096 (7) | 0.053 (4) | 0.079 (5) | 0.029 (4) | 0.008 (4) | 0.011 (3) |
Cu1—O4i | 1.955 (3) | C2—C4 | 1.381 (7) |
Cu1—O2ii | 1.966 (3) | C2—H2A | 0.9300 |
Cu1—N2 | 1.999 (4) | C3—C6 | 1.384 (6) |
Cu1—N1 | 2.052 (4) | C3—C4 | 1.388 (6) |
Cu1—O5 | 2.396 (4) | C3—H3C | 0.9300 |
O1—C7 | 1.226 (6) | C5—C6 | 1.384 (7) |
O2—C7 | 1.277 (6) | C5—H5A | 0.9300 |
O2—Cu1iii | 1.966 (3) | C6—C7 | 1.511 (6) |
O3—C1 | 1.228 (6) | C8—C9 | 1.362 (8) |
O4—C1 | 1.281 (5) | C8—H8A | 0.9300 |
O4—Cu1iv | 1.955 (3) | C9—C10 | 1.390 (8) |
O5—C13 | 1.225 (7) | C9—H9A | 0.9300 |
N1—C5 | 1.332 (6) | C10—C11 | 1.387 (8) |
N1—C2 | 1.349 (6) | C11—C12 | 1.368 (8) |
N2—C8 | 1.330 (7) | C11—H11A | 0.9300 |
N2—C12 | 1.346 (6) | C12—H12A | 0.9300 |
N3—C10 | 1.337 (7) | C13—H13A | 0.9300 |
N3—H3A | 0.8600 | C14—H14A | 0.9600 |
N3—H3B | 0.8600 | C14—H14B | 0.9600 |
N4—C13 | 1.322 (8) | C14—H14C | 0.9600 |
N4—C14 | 1.428 (9) | C15—H15A | 0.9600 |
N4—C15 | 1.440 (9) | C15—H15B | 0.9600 |
C1—C4 | 1.506 (6) | C15—H15C | 0.9600 |
O4i—Cu1—O2ii | 178.46 (14) | N1—C5—H5A | 118.4 |
O4i—Cu1—N2 | 88.29 (16) | C6—C5—H5A | 118.4 |
O2ii—Cu1—N2 | 91.42 (16) | C3—C6—C5 | 118.5 (4) |
O4i—Cu1—N1 | 90.10 (14) | C3—C6—C7 | 121.1 (4) |
O2ii—Cu1—N1 | 90.16 (14) | C5—C6—C7 | 120.4 (4) |
N2—Cu1—N1 | 177.93 (16) | O1—C7—O2 | 125.0 (5) |
O4i—Cu1—O5 | 90.59 (16) | O1—C7—C6 | 120.1 (4) |
O2ii—Cu1—O5 | 90.93 (16) | O2—C7—C6 | 114.9 (4) |
N2—Cu1—O5 | 91.74 (16) | N2—C8—C9 | 124.2 (5) |
N1—Cu1—O5 | 89.57 (16) | N2—C8—H8A | 117.9 |
C7—O2—Cu1iii | 114.6 (3) | C9—C8—H8A | 117.9 |
C1—O4—Cu1iv | 118.5 (3) | C8—C9—C10 | 119.9 (5) |
C13—O5—Cu1 | 141.8 (5) | C8—C9—H9A | 120.0 |
C5—N1—C2 | 117.7 (4) | C10—C9—H9A | 120.0 |
C5—N1—Cu1 | 121.4 (3) | N3—C10—C11 | 120.7 (5) |
C2—N1—Cu1 | 120.0 (3) | N3—C10—C9 | 123.3 (5) |
C8—N2—C12 | 116.2 (5) | C11—C10—C9 | 116.0 (5) |
C8—N2—Cu1 | 122.5 (3) | C12—C11—C10 | 120.5 (5) |
C12—N2—Cu1 | 121.3 (4) | C12—C11—H11A | 119.8 |
C10—N3—H3A | 120.0 | C10—C11—H11A | 119.8 |
C10—N3—H3B | 120.0 | N2—C12—C11 | 123.0 (5) |
H3A—N3—H3B | 120.0 | N2—C12—H12A | 118.5 |
C13—N4—C14 | 120.0 (7) | C11—C12—H12A | 118.5 |
C13—N4—C15 | 121.0 (6) | O5—C13—N4 | 125.5 (6) |
C14—N4—C15 | 119.0 (7) | O5—C13—H13A | 117.3 |
O3—C1—O4 | 126.0 (4) | N4—C13—H13A | 117.3 |
O3—C1—C4 | 119.6 (4) | N4—C14—H14A | 109.5 |
O4—C1—C4 | 114.4 (4) | N4—C14—H14B | 109.5 |
N1—C2—C4 | 123.0 (4) | H14A—C14—H14B | 109.5 |
N1—C2—H2A | 118.5 | N4—C14—H14C | 109.5 |
C4—C2—H2A | 118.5 | H14A—C14—H14C | 109.5 |
C6—C3—C4 | 119.1 (4) | H14B—C14—H14C | 109.5 |
C6—C3—H3C | 120.5 | N4—C15—H15A | 109.5 |
C4—C3—H3C | 120.5 | N4—C15—H15B | 109.5 |
C2—C4—C3 | 118.4 (4) | H15A—C15—H15B | 109.5 |
C2—C4—C1 | 120.1 (4) | N4—C15—H15C | 109.5 |
C3—C4—C1 | 121.3 (4) | H15A—C15—H15C | 109.5 |
N1—C5—C6 | 123.3 (4) | H15B—C15—H15C | 109.5 |
Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) −x, y−1/2, −z+3/2; (iii) −x, y+1/2, −z+3/2; (iv) x+1/2, −y+1/2, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O3v | 0.86 | 2.28 | 3.101 (7) | 159 |
N3—H3B···O1vi | 0.86 | 2.23 | 2.933 (7) | 139 |
Symmetry codes: (v) x−1, y−1, z; (vi) −x−1, y−1/2, −z+3/2. |
Acknowledgements
This work was supported by the National Natural Science Foundation of China (No. 21471086), the Social Development Foundation of Ningbo (No. 2014C50013) and the K. C. Wong MagnaFund in Ningbo University.
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