metal-organic compounds
catena-poly[[[aquabis(1H-imidazole-κN3)copper(II)]-μ-3-({4-[(2-carboxylatoethyl)carbamoyl]phenyl}formamido)propanoato-κ2O:O′] dihydrate]
ofaCollege of Chemistry and Materials Science, Anhui Key Laboratory of Functional Molecular Solids, Anhui Normal University, Wuhu 241000, People's Republic of China
*Correspondence e-mail: zht2006@mail.ahnu.edu.cn
In the title polymeric complex, {[Cu(C14H14N2O6)(C3H4N2)2(H2O)]·2H2O}n, the CuII cation, located on a twofold rotation axis, is coordinated by one water molecule and two imidazole molecules as well as two symmetry-related 3-([4-[(2-carboxylatoethyl)carbamoyl]phenyl]formamido)propanoate dianions (L2−) in an approximately square-pyramidal geometry. The coordinating water molecule is located on a twofold rotation axis while the L2− anion sits about an inversion center. The L2− anions bridge the CuII cations, forming polymeric chains propagating along the [101] direction. In the crystal, O—H⋯O, N—H⋯O hydrogen bonds and weak C—H⋯π interaction link the polymeric chains and the solvent water molecules into a three-dimensional supramolecular architecture.
CCDC reference: 1056415
1. Related literature
For related coordination polymers, see: Morrison et al. (2011); Wang et al. (2012); Zhang & Xiong (2012). For the synthesis, see: Yuan et al. (2002).
2. Experimental
2.1. Crystal data
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2.3. Refinement
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Data collection: APEX2 (Bruker, 2004); cell SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: DIAMOND (Brandenburg, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
CCDC reference: 1056415
https://doi.org/10.1107/S205698901500626X/xu5844sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901500626X/xu5844Isup2.hkl
The ligand H2L was synthesized from terephthaloyl chloride and β-alanine according to a similar method reported by Yuan et al. (2002). 13.6 mg (0.2 mmol) imidazole was dissolved in 10 ml water and then the ligand (30.8 mg, 0.1 mmol) was added in the solution. After H2L dissolved completely, The cupric acetate monohydrate (20.0 mg 0.1 mmol) was added in the solution. The resulting blue solution was filtered and the filtrate was left at room temperature. Blue block crystals of (I) were obtained (36.4 mg, yield ca 65%) after several weeks by slow evaporation of the solvent.
H atoms were placed in calculated positions with C—H = 0.93–0.97 Å, O—H = 0.82–0.85 Å and N—H = 0.86 Å, and refined in riding mode.
The self-assembly of coordination polymers have been one of the popular areas of in chemistry recently, owing to their intriguing structures and various physical properties, such as optical, electronic, magnetic and catalytic properties (Zhang et al. 2012, Wang et al. 2012). From the view point of the intermolecular interactions, the structures of the coordination polymers are mainly governed by the intra- and intermolecular interactions, such as the coordination interaction, hydrogen bonding interaction and π···π stacking as well as the molecular conformations depending on the molecular flexibility (Morrison et al. 2011). Accordingly, the aromatic pseudopeptidic molecules bearing the carboxylate groups could be the ideal building blocks to construct the coordination polymers with the metal ions. The σ-rotation about the N—C and the C—C bonds could induce flexibility in the molecules. The imine group N—H could serve as a better hydrogen-bonding donor and the amide C=O could also act as a better hydrogen-bonding acceptor. Moreover, the aromatic rings in the molecules could contribute to π···π stacking. The carboxlate groups in the molecules could capture the metal ions through the coordination interaction. Therefore, we have designed and synthesized an aromatic pseudopeptidic ligand, 3,3'-[1,4-bis(- benzamido)]dipropanoic acid (H2L). Here, we report the structure of the title helical chain-like coordination polymer, (I), which is derived from aromatic pseudopeptidic ligand, L2-, and imidazole, namely {[CuL(im)2(H2O)]2(H2O)}n (im = imidazole), (I).
X-ray crystallographic analysis revealed that (I) crystallizes in the monoclinic π···π staking in the crystal. Therefore, the helical chains are stabilized in the lattice mainly by the hydrogen bonding interactions and van der Waals interactions.
C2/c with an consisting of a divalent CuII cation and a coordinated water molecule residing on a twofold axis, half of an L2- siting across a center of inversion and one imidazole as well as a lattice water molecule. As shown in Fig 1, the five-coordinate CuII cation has an approximately square-pyramidal coordination environment,in which the equatorial plane is composed of two N atoms (N2 and N2i, symmetry code:(i) 1 - x, y, -z + 3/2) from two imidazole molecules and two O atoms (O1 and O1i,symmetry code:(i) 1 - x, y, -z + 3/2) from two symmetry related L2- dianions, while the water O atom (O4) occupies the apical position (Table 1). The apical Cu1—O4 distance is longer than the others,including the Cu—O1 and the Cu—N2 disatnces. The angles O1—Cu1—O1i and N2—Cu—N2i (symmetry code:(i) 1 - x, y, -z + 3/2) are of 177.05 (18) ° and 173.3 (2) °, respectively. It indicates that these five atoms are approximately located in an equatorial plane. The angles O4—Cu1—O1 and O4—Cu1—N2 are of 91.47 (9)° and 93.36 (10)°, which confirm an approximately square-pyramidal coordination geometry. The carboxylate group O1/C1/O2 coordinates to CuII cation in monodentate fashion via the atom O1. As a result, the ligand dianions connect the copper cations to construct an helical chain which runs along the [101] direction. In the formation of the single-strand helical structure, the peptide segment could play an important role. The torsion angle C1/C2/C3/N1 is of 59.8 (5)°, which is very close to 60 °. It shows the conformation of the peptide segment. It also makes the ligand molecule twist twice and finally construct a single-strand helix through connecting the copper cations. It implies that the conformation of the ligand could be crucial in the formation of the helix. In the lattice, there are two types of helix, viz. right-handed and left-handed. Helices of the same type arrange in parallel along the b axis. The inter-chain hydrogen bonding interactions could contribute to the arrangement of the same type helices. The hydrogen bonding interactions between the lattice water molecules and the helices could contribute to the arrangement of the different type helices. However, the shortest center-center distance between two adjacent phenyl rings is beyond 5 Å. It indicates the absence ofFor related coordination polymers, see: Morrison et al. (2011); Wang et al. (2012); Zhang & Xiong (2012). For the synthesis, see: Yuan et al. (2002).
Data collection: APEX2 (Bruker, 2004); cell
SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).Fig. 1. The molecular structure of (I), a drawing of the asymmetric unit (multi-colored portion) with displacement ellipsoids at the 30% probability level. [symmetry code: (i) 1 - x, y, -z + 3/2; (ii) -x + 1/2, -y + 3/2, -z + 1] | |
Fig. 2. The polymeric chain of (I). |
[Cu(C14H14N2O6)(C3H4N2)2(H2O)]·2H2O | F(000) = 1164 |
Mr = 560.02 | Dx = 1.543 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 1477 reflections |
a = 27.752 (5) Å | θ = 2.4–20.7° |
b = 5.5793 (9) Å | µ = 0.97 mm−1 |
c = 17.302 (3) Å | T = 298 K |
β = 115.855 (2)° | Block, blue |
V = 2410.8 (7) Å3 | 0.08 × 0.07 × 0.05 mm |
Z = 4 |
Bruker SMART APEXII CCD area-detector diffractometer | 2775 independent reflections |
Radiation source: fine-focus sealed tube | 1632 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.081 |
phi and ω scans | θmax = 27.5°, θmin = 1.6° |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | h = −35→36 |
Tmin = 0.927, Tmax = 0.958 | k = −7→7 |
9928 measured reflections | l = −22→22 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.053 | w = 1/[σ2(Fo2) + (0.0621P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.139 | (Δ/σ)max < 0.001 |
S = 0.99 | Δρmax = 0.58 e Å−3 |
2775 reflections | Δρmin = −0.36 e Å−3 |
165 parameters |
[Cu(C14H14N2O6)(C3H4N2)2(H2O)]·2H2O | V = 2410.8 (7) Å3 |
Mr = 560.02 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 27.752 (5) Å | µ = 0.97 mm−1 |
b = 5.5793 (9) Å | T = 298 K |
c = 17.302 (3) Å | 0.08 × 0.07 × 0.05 mm |
β = 115.855 (2)° |
Bruker SMART APEXII CCD area-detector diffractometer | 2775 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | 1632 reflections with I > 2σ(I) |
Tmin = 0.927, Tmax = 0.958 | Rint = 0.081 |
9928 measured reflections |
R[F2 > 2σ(F2)] = 0.053 | 0 restraints |
wR(F2) = 0.139 | H-atom parameters constrained |
S = 0.99 | Δρmax = 0.58 e Å−3 |
2775 reflections | Δρmin = −0.36 e Å−3 |
165 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 | ||
C1 | 0.44842 (17) | 0.1862 (8) | 0.5751 (3) | 0.0456 (11) | |
C2 | 0.42650 (18) | 0.2325 (8) | 0.4802 (2) | 0.0498 (11) | |
H2A | 0.3936 | 0.1421 | 0.4512 | 0.060* | |
H2B | 0.4519 | 0.1722 | 0.4603 | 0.060* | |
C3 | 0.41500 (19) | 0.4960 (9) | 0.4541 (3) | 0.0560 (12) | |
H3A | 0.4483 | 0.5854 | 0.4803 | 0.067* | |
H3B | 0.4018 | 0.5081 | 0.3923 | 0.067* | |
C4 | 0.32380 (18) | 0.5588 (8) | 0.4379 (3) | 0.0494 (11) | |
C5 | 0.28700 (17) | 0.6644 (8) | 0.4710 (3) | 0.0473 (11) | |
C6 | 0.29707 (18) | 0.8736 (8) | 0.5187 (3) | 0.0516 (11) | |
H6 | 0.3285 | 0.9585 | 0.5317 | 0.062* | |
C7 | 0.26074 (18) | 0.9564 (8) | 0.5468 (3) | 0.0520 (12) | |
H7 | 0.2682 | 1.0972 | 0.5787 | 0.062* | |
C8 | 0.38648 (18) | 0.5107 (8) | 0.6976 (3) | 0.0516 (11) | |
H8 | 0.3900 | 0.6493 | 0.6707 | 0.062* | |
C9 | 0.34147 (18) | 0.4422 (9) | 0.7033 (3) | 0.0553 (12) | |
H9 | 0.3090 | 0.5235 | 0.6825 | 0.066* | |
C10 | 0.40408 (18) | 0.1793 (8) | 0.7653 (3) | 0.0494 (11) | |
H10 | 0.4216 | 0.0426 | 0.7951 | 0.059* | |
Cu1 | 0.5000 | 0.36573 (12) | 0.7500 | 0.0343 (2) | |
N1 | 0.37603 (14) | 0.6062 (6) | 0.4788 (2) | 0.0509 (9) | |
H1 | 0.3872 | 0.7051 | 0.5211 | 0.061* | |
N2 | 0.42632 (12) | 0.3451 (6) | 0.73776 (19) | 0.0404 (8) | |
N3 | 0.35351 (14) | 0.2310 (7) | 0.7454 (2) | 0.0526 (10) | |
H3 | 0.3320 | 0.1446 | 0.7573 | 0.063* | |
O1 | 0.47315 (11) | 0.3567 (5) | 0.62383 (16) | 0.0461 (7) | |
O2 | 0.43997 (16) | −0.0138 (6) | 0.59984 (19) | 0.0772 (11) | |
O3 | 0.30600 (12) | 0.4261 (6) | 0.3745 (2) | 0.0640 (9) | |
O4 | 0.5000 | 0.7658 (7) | 0.7500 | 0.0613 (13) | |
H4 | 0.5172 | 0.8147 | 0.7992 | 0.092* | |
O5 | 0.28059 (12) | −0.0023 (6) | 0.7868 (2) | 0.0658 (9) | |
H5A | 0.2944 | −0.1316 | 0.8131 | 0.079* | |
H5B | 0.2528 | −0.0347 | 0.7410 | 0.079* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.047 (3) | 0.047 (3) | 0.033 (2) | 0.009 (2) | 0.009 (2) | −0.002 (2) |
C2 | 0.057 (3) | 0.049 (3) | 0.034 (2) | 0.007 (2) | 0.011 (2) | −0.002 (2) |
C3 | 0.053 (3) | 0.068 (3) | 0.043 (3) | 0.002 (2) | 0.017 (2) | 0.006 (2) |
C4 | 0.050 (3) | 0.047 (3) | 0.038 (2) | 0.004 (2) | 0.006 (2) | 0.005 (2) |
C5 | 0.051 (3) | 0.039 (3) | 0.037 (2) | 0.002 (2) | 0.006 (2) | −0.0019 (19) |
C6 | 0.046 (3) | 0.045 (3) | 0.049 (3) | −0.005 (2) | 0.007 (2) | −0.002 (2) |
C7 | 0.055 (3) | 0.039 (3) | 0.046 (3) | −0.002 (2) | 0.008 (2) | −0.006 (2) |
C8 | 0.049 (3) | 0.057 (3) | 0.048 (3) | 0.007 (2) | 0.020 (2) | 0.009 (2) |
C9 | 0.036 (3) | 0.068 (3) | 0.056 (3) | 0.007 (2) | 0.015 (2) | 0.005 (3) |
C10 | 0.047 (3) | 0.050 (3) | 0.048 (3) | 0.003 (2) | 0.018 (2) | 0.000 (2) |
Cu1 | 0.0316 (4) | 0.0344 (4) | 0.0312 (4) | 0.000 | 0.0084 (3) | 0.000 |
N1 | 0.049 (2) | 0.052 (2) | 0.042 (2) | −0.0002 (19) | 0.0110 (18) | −0.0060 (17) |
N2 | 0.0350 (19) | 0.047 (2) | 0.0358 (18) | −0.0022 (17) | 0.0122 (15) | 0.0007 (16) |
N3 | 0.041 (2) | 0.063 (3) | 0.054 (2) | −0.0093 (19) | 0.0211 (19) | −0.006 (2) |
O1 | 0.0432 (17) | 0.0548 (18) | 0.0342 (15) | −0.0116 (15) | 0.0112 (13) | −0.0034 (14) |
O2 | 0.116 (3) | 0.040 (2) | 0.0441 (19) | 0.000 (2) | 0.0056 (19) | 0.0014 (16) |
O3 | 0.058 (2) | 0.061 (2) | 0.054 (2) | −0.0011 (17) | 0.0068 (17) | −0.0206 (16) |
O4 | 0.075 (3) | 0.038 (2) | 0.040 (2) | 0.000 | −0.004 (2) | 0.000 |
O5 | 0.052 (2) | 0.063 (2) | 0.069 (2) | −0.0075 (17) | 0.0134 (17) | 0.0111 (18) |
C1—O2 | 1.253 (5) | C8—C9 | 1.350 (6) |
C1—O1 | 1.259 (5) | C8—N2 | 1.374 (5) |
C1—C2 | 1.503 (5) | C8—H8 | 0.9300 |
C2—C3 | 1.531 (6) | C9—N3 | 1.348 (6) |
C2—H2A | 0.9700 | C9—H9 | 0.9300 |
C2—H2B | 0.9700 | C10—N2 | 1.312 (5) |
C3—N1 | 1.460 (5) | C10—N3 | 1.323 (5) |
C3—H3A | 0.9700 | C10—H10 | 0.9300 |
C3—H3B | 0.9700 | Cu1—N2ii | 1.965 (3) |
C4—O3 | 1.234 (5) | Cu1—N2 | 1.965 (3) |
C4—N1 | 1.333 (5) | Cu1—O1ii | 1.976 (3) |
C4—C5 | 1.492 (6) | Cu1—O1 | 1.976 (3) |
C5—C6 | 1.386 (6) | Cu1—O4 | 2.232 (4) |
C5—C7i | 1.396 (6) | N1—H1 | 0.8600 |
C6—C7 | 1.377 (6) | N3—H3 | 0.8600 |
C6—H6 | 0.9300 | O4—H4 | 0.8200 |
C7—C5i | 1.396 (6) | O5—H5A | 0.8500 |
C7—H7 | 0.9300 | O5—H5B | 0.8500 |
O2—C1—O1 | 124.9 (4) | N2—C8—H8 | 125.1 |
O2—C1—C2 | 118.7 (4) | N3—C9—C8 | 105.5 (4) |
O1—C1—C2 | 116.4 (4) | N3—C9—H9 | 127.3 |
C1—C2—C3 | 114.9 (4) | C8—C9—H9 | 127.3 |
C1—C2—H2A | 108.5 | N2—C10—N3 | 111.4 (4) |
C3—C2—H2A | 108.5 | N2—C10—H10 | 124.3 |
C1—C2—H2B | 108.5 | N3—C10—H10 | 124.3 |
C3—C2—H2B | 108.5 | N2ii—Cu1—N2 | 173.3 (2) |
H2A—C2—H2B | 107.5 | N2ii—Cu1—O1ii | 90.35 (12) |
N1—C3—C2 | 113.8 (4) | N2—Cu1—O1ii | 89.48 (12) |
N1—C3—H3A | 108.8 | N2ii—Cu1—O1 | 89.48 (12) |
C2—C3—H3A | 108.8 | N2—Cu1—O1 | 90.35 (11) |
N1—C3—H3B | 108.8 | O1ii—Cu1—O1 | 177.09 (18) |
C2—C3—H3B | 108.8 | N2ii—Cu1—O4 | 93.36 (10) |
H3A—C3—H3B | 107.7 | N2—Cu1—O4 | 93.36 (10) |
O3—C4—N1 | 120.7 (4) | O1ii—Cu1—O4 | 91.46 (9) |
O3—C4—C5 | 120.1 (4) | O1—Cu1—O4 | 91.46 (9) |
N1—C4—C5 | 119.1 (4) | C4—N1—C3 | 122.3 (4) |
C6—C5—C7i | 117.6 (4) | C4—N1—H1 | 118.8 |
C6—C5—C4 | 124.5 (4) | C3—N1—H1 | 118.8 |
C7i—C5—C4 | 117.9 (4) | C10—N2—C8 | 104.8 (4) |
C7—C6—C5 | 120.3 (4) | C10—N2—Cu1 | 129.4 (3) |
C7—C6—H6 | 119.8 | C8—N2—Cu1 | 125.8 (3) |
C5—C6—H6 | 119.8 | C10—N3—C9 | 108.5 (4) |
C6—C7—C5i | 122.1 (4) | C10—N3—H3 | 125.8 |
C6—C7—H7 | 119.0 | C9—N3—H3 | 125.8 |
C5i—C7—H7 | 119.0 | C1—O1—Cu1 | 126.4 (3) |
C9—C8—N2 | 109.8 (4) | Cu1—O4—H4 | 109.5 |
C9—C8—H8 | 125.1 | H5A—O5—H5B | 109.5 |
Symmetry codes: (i) −x+1/2, −y+3/2, −z+1; (ii) −x+1, y, −z+3/2. |
Cg1 is the centroid of the N2/N3/C8–C10 imidazole ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O2iii | 0.86 | 2.17 | 2.965 (5) | 153 |
N3—H3···O5 | 0.86 | 1.90 | 2.751 (5) | 172 |
O4—H4···O2iv | 0.82 | 1.89 | 2.695 (4) | 167 |
O5—H5A···O3v | 0.85 | 1.91 | 2.731 (4) | 163 |
O5—H5B···O3vi | 0.85 | 2.04 | 2.810 (4) | 149 |
C3—H3B···Cg1vii | 0.93 | 2.75 | 3.692 (5) | 164 |
Symmetry codes: (iii) x, y+1, z; (iv) −x+1, y+1, −z+3/2; (v) x, −y, z+1/2; (vi) −x+1/2, −y+1/2, −z+1; (vii) −x+1/2, y+3/2, −z−1/2. |
Cg1 is the centroid of the N2/N3/C8–C10 imidazole ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O2i | 0.86 | 2.17 | 2.965 (5) | 153 |
N3—H3···O5 | 0.86 | 1.90 | 2.751 (5) | 172 |
O4—H4···O2ii | 0.82 | 1.89 | 2.695 (4) | 167 |
O5—H5A···O3iii | 0.85 | 1.91 | 2.731 (4) | 163 |
O5—H5B···O3iv | 0.85 | 2.04 | 2.810 (4) | 149 |
C3—H3B···Cg1v | 0.93 | 2.75 | 3.692 (5) | 164 |
Symmetry codes: (i) x, y+1, z; (ii) −x+1, y+1, −z+3/2; (iii) x, −y, z+1/2; (iv) −x+1/2, −y+1/2, −z+1; (v) −x+1/2, y+3/2, −z−1/2. |
Acknowledgements
This work was supported by the Department of Education of Anhui Province, China (KJ2007B099).
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The self-assembly of coordination polymers have been one of the popular areas of in chemistry recently, owing to their intriguing structures and various physical properties, such as optical, electronic, magnetic and catalytic properties (Zhang et al. 2012, Wang et al. 2012). From the view point of the intermolecular interactions, the structures of the coordination polymers are mainly governed by the intra- and intermolecular interactions, such as the coordination interaction, hydrogen bonding interaction and π···π stacking as well as the molecular conformations depending on the molecular flexibility (Morrison et al. 2011). Accordingly, the aromatic pseudopeptidic molecules bearing the carboxylate groups could be the ideal building blocks to construct the coordination polymers with the metal ions. The σ-rotation about the N—C and the C—C bonds could induce flexibility in the molecules. The imine group N—H could serve as a better hydrogen-bonding donor and the amide C=O could also act as a better hydrogen-bonding acceptor. Moreover, the aromatic rings in the molecules could contribute to π···π stacking. The carboxlate groups in the molecules could capture the metal ions through the coordination interaction. Therefore, we have designed and synthesized an aromatic pseudopeptidic ligand, 3,3'-[1,4-bis(- benzamido)]dipropanoic acid (H2L). Here, we report the structure of the title helical chain-like coordination polymer, (I), which is derived from aromatic pseudopeptidic ligand, L2-, and imidazole, namely {[CuL(im)2(H2O)]2(H2O)}n (im = imidazole), (I).
X-ray crystallographic analysis revealed that (I) crystallizes in the monoclinic space group C2/c with an asymmetric unit consisting of a divalent CuII cation and a coordinated water molecule residing on a twofold axis, half of an L2- siting across a center of inversion and one imidazole as well as a lattice water molecule. As shown in Fig 1, the five-coordinate CuII cation has an approximately square-pyramidal coordination environment,in which the equatorial plane is composed of two N atoms (N2 and N2i, symmetry code:(i) 1 - x, y, -z + 3/2) from two imidazole molecules and two O atoms (O1 and O1i,symmetry code:(i) 1 - x, y, -z + 3/2) from two symmetry related L2- dianions, while the water O atom (O4) occupies the apical position (Table 1). The apical Cu1—O4 distance is longer than the others,including the Cu—O1 and the Cu—N2 disatnces. The angles O1—Cu1—O1i and N2—Cu—N2i (symmetry code:(i) 1 - x, y, -z + 3/2) are of 177.05 (18) ° and 173.3 (2) °, respectively. It indicates that these five atoms are approximately located in an equatorial plane. The angles O4—Cu1—O1 and O4—Cu1—N2 are of 91.47 (9)° and 93.36 (10)°, which confirm an approximately square-pyramidal coordination geometry. The carboxylate group O1/C1/O2 coordinates to CuII cation in monodentate fashion via the atom O1. As a result, the ligand dianions connect the copper cations to construct an helical chain which runs along the [101] direction. In the formation of the single-strand helical structure, the peptide segment could play an important role. The torsion angle C1/C2/C3/N1 is of 59.8 (5)°, which is very close to 60 °. It shows the gauche conformation of the peptide segment. It also makes the ligand molecule twist twice and finally construct a single-strand helix through connecting the copper cations. It implies that the conformation of the ligand could be crucial in the formation of the helix. In the lattice, there are two types of helix, viz. right-handed and left-handed. Helices of the same type arrange in parallel along the b axis. The inter-chain hydrogen bonding interactions could contribute to the arrangement of the same type helices. The hydrogen bonding interactions between the lattice water molecules and the helices could contribute to the arrangement of the different type helices. However, the shortest center-center distance between two adjacent phenyl rings is beyond 5 Å. It indicates the absence of π···π staking in the crystal. Therefore, the helical chains are stabilized in the lattice mainly by the hydrogen bonding interactions and van der Waals interactions.