Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S160053680702243X/hb2367sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S160053680702243X/hb2367Isup2.hkl |
CCDC reference: 650617
Solid CdCO3 (1 mmol, 0.172 g) was added to an aqueous solution (25 ml) of 2,4-dihydroxybenzoic acid (2.0 mmol, 0.308 g). The mixture was stirred for 10 minutes under the temperature of 373 K. The solution was filtered, and the filtrate was kept at the room temperature. After ten days weeks, colorless crystals of (I) were obtained.
The H atoms bonded to water were located in a difference synthesis and refined with distance restraints O—H = 0.82 (1) Å and H···H = 1.34 (2) Å and Uiso(H) = Ueq(O). The remaining H atoms were positioned geometrically, with C—H = 0.93 Å and O—H = 0.82 Å, and were refined as riding with Uiso(H) = 1.2Ueq(C) and Uiso(H) = 1.5Ueq(O).
Design and synthesis of metal coordination polymers based on benzene carboxylates have been attracting chemist's interests and constitutes an important area of research (Thirumurugan & Natarajan, 2004). During the past years, lots of novel benzene multicarboxylates base compounds have been reported (Tao et al., 2000; Zhang et al., 2005). However, in those reported literatures, the common features tried to construct predictable one-, two, three-dimensional coordination networks by changing the numbers or relative position of carboxylates. In contrast, benzene carboxylates containing the hydroxyl can be utilized to coordinate to metal ions and generate unusual structures have never been reported. Herein, we report the title compound (I).
The title compound (I) present a one-dimensional chain [Cd(C7O4H5)2(H2O)2]n, in which Cd2+ is coordinated by four oxygen atoms from two 2,4-dihydroxybenzoate anion, two water molecules, and one oxygen from the hydroxyl of another 2,4-dihydroxybenzoate anion. The environment of Cd ion is in a distorted pentagonal bipyramid (Fig. 1). In the equatorial plane, Cd1 ion is coordinated by four carboxylates oxygen (O1, O2, O5, O6) and one oxygen (O3b) of the hydroxyl. The Cd1—O distances range from 2.327 (2) to 2.459 (2)Å (Table 1). The mean deviation from the equatorial plane is 0.129 Å. The axial sites are occupied by two water oxygen atoms (O9 and O10) with Cd1—O lengths ranging from 2.196 (2) to 2.268 (3)Å (Table 1). The obvious differences of Cd1—O length show that the water more greatly interact with the Cd2+ ion than that of the carboxylate. The axial O9—Cd1—O10 bond angle is 177.80 (9) Å.
In addition, the intra-molecular hydrogen bonds exhibit in the compound, O7—H7 and O3—H31 acting as hydrogen bond donor, and O6 and O1 as hydrogen bond acceptor, constructing two S(6) rings (Fig. 1, Table 2). These units are linked into a one-dimensional chain-like structure by the hydroxyl oxygen atom O3 (Fig. 2).
For related literature, see: Tao et al. (2000), Thirumurugan & Natarajan (2004) and Zhang et al. (2005).
Data collection: SMART (Bruker, 2001); cell refinement: SMART-Plus (Bruker, 2001); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PLATON.
[Cd(C7H5O4)2(H2O)2] | F(000) = 1808 |
Mr = 454.65 | Dx = 1.912 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 5177 reflections |
a = 11.964 (2) Å | θ = 3.0–28.2° |
b = 7.7882 (16) Å | µ = 1.44 mm−1 |
c = 33.893 (7) Å | T = 292 K |
V = 3158.1 (11) Å3 | Plate, colourless |
Z = 8 | 0.35 × 0.20 × 0.04 mm |
Bruker SMART APEX CCD area-detector diffractometer | 3063 independent reflections |
Radiation source: fine-focus sealed tube | 2847 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.036 |
ω scans | θmax = 26.0°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | h = −14→14 |
Tmin = 0.633, Tmax = 0.945 | k = −9→9 |
19791 measured reflections | l = −41→41 |
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)] = 0.029 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.069 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0295P)2 + 3.765P] where P = (Fo2 + 2Fc2)/3 |
3063 reflections | (Δ/σ)max = 0.002 |
248 parameters | Δρmax = 0.48 e Å−3 |
18 restraints | Δρmin = −0.47 e Å−3 |
[Cd(C7H5O4)2(H2O)2] | V = 3158.1 (11) Å3 |
Mr = 454.65 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 11.964 (2) Å | µ = 1.44 mm−1 |
b = 7.7882 (16) Å | T = 292 K |
c = 33.893 (7) Å | 0.35 × 0.20 × 0.04 mm |
Bruker SMART APEX CCD area-detector diffractometer | 3063 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | 2847 reflections with I > 2σ(I) |
Tmin = 0.633, Tmax = 0.945 | Rint = 0.036 |
19791 measured reflections |
R[F2 > 2σ(F2)] = 0.029 | 18 restraints |
wR(F2) = 0.069 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.48 e Å−3 |
3063 reflections | Δρmin = −0.47 e Å−3 |
248 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 | 0.903474 (16) | 0.23166 (3) | 0.448614 (5) | 0.02615 (9) | |
O1 | 0.75857 (17) | 0.2302 (3) | 0.50006 (5) | 0.0358 (5) | |
O2 | 0.93525 (17) | 0.2420 (3) | 0.51741 (6) | 0.0370 (5) | |
O3 | 0.60334 (16) | 0.2867 (4) | 0.54931 (6) | 0.0423 (6) | |
H31 | 0.635 (4) | 0.265 (5) | 0.5293 (14) | 0.063* | |
O4 | 0.69862 (19) | 0.4547 (4) | 0.67789 (7) | 0.0659 (8) | |
H4A | 0.7529 | 0.4701 | 0.6922 | 0.099* | |
O5 | 0.74055 (18) | 0.2508 (3) | 0.40614 (6) | 0.0383 (5) | |
O6 | 0.90716 (16) | 0.2860 (3) | 0.38111 (6) | 0.0411 (5) | |
O7 | 0.93668 (17) | 0.3721 (4) | 0.30975 (6) | 0.0560 (7) | |
H7 | 0.9543 | 0.3431 | 0.3322 | 0.084* | |
O8 | 0.62706 (19) | 0.4682 (4) | 0.22892 (7) | 0.0636 (8) | |
H8 | 0.5632 | 0.4326 | 0.2256 | 0.095* | |
O9 | 0.91561 (19) | −0.0476 (3) | 0.44064 (8) | 0.0487 (6) | |
H91 | 0.9608 (19) | −0.100 (3) | 0.4540 (8) | 0.033 (9)* | |
H92 | 0.871 (2) | −0.113 (3) | 0.4305 (9) | 0.039 (9)* | |
O10 | 0.8982 (2) | 0.5205 (3) | 0.45687 (8) | 0.0489 (6) | |
H101 | 0.949 (2) | 0.571 (4) | 0.4677 (8) | 0.049* | |
H102 | 0.886 (3) | 0.551 (4) | 0.4348 (4) | 0.049* | |
C1 | 0.8319 (2) | 0.2536 (3) | 0.52658 (8) | 0.0288 (6) | |
C2 | 0.7975 (2) | 0.3003 (4) | 0.56677 (7) | 0.0260 (5) | |
C3 | 0.6847 (2) | 0.3185 (4) | 0.57667 (7) | 0.0274 (6) | |
C4 | 0.6530 (2) | 0.3707 (4) | 0.61387 (8) | 0.0373 (7) | |
H4 | 0.5778 | 0.3843 | 0.6200 | 0.045* | |
C5 | 0.7336 (2) | 0.4025 (4) | 0.64192 (8) | 0.0374 (7) | |
C6 | 0.8462 (2) | 0.3834 (5) | 0.63318 (8) | 0.0412 (8) | |
H6 | 0.9002 | 0.4036 | 0.6524 | 0.049* | |
C7 | 0.8769 (2) | 0.3343 (5) | 0.59590 (9) | 0.0383 (7) | |
H7A | 0.9524 | 0.3234 | 0.5899 | 0.046* | |
C8 | 0.8016 (2) | 0.2865 (4) | 0.37699 (8) | 0.0310 (6) | |
C9 | 0.7541 (2) | 0.3296 (4) | 0.33825 (8) | 0.0312 (6) | |
C10 | 0.8238 (2) | 0.3718 (4) | 0.30639 (8) | 0.0357 (7) | |
C11 | 0.7786 (2) | 0.4173 (5) | 0.27043 (8) | 0.0448 (8) | |
H11 | 0.8254 | 0.4477 | 0.2497 | 0.054* | |
C12 | 0.6648 (3) | 0.4178 (5) | 0.26516 (9) | 0.0432 (8) | |
C13 | 0.5936 (2) | 0.3759 (6) | 0.29596 (10) | 0.0500 (10) | |
H13 | 0.5165 | 0.3771 | 0.2924 | 0.060* | |
C14 | 0.6393 (2) | 0.3325 (5) | 0.33174 (9) | 0.0411 (8) | |
H14 | 0.5917 | 0.3038 | 0.3524 | 0.049* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.02635 (12) | 0.03452 (14) | 0.01758 (12) | 0.00370 (8) | −0.00053 (7) | −0.00107 (8) |
O1 | 0.0321 (10) | 0.0571 (14) | 0.0182 (9) | 0.0013 (9) | −0.0009 (8) | −0.0076 (9) |
O2 | 0.0271 (10) | 0.0589 (14) | 0.0249 (11) | 0.0110 (9) | 0.0036 (8) | −0.0027 (9) |
O3 | 0.0221 (11) | 0.0808 (18) | 0.0240 (12) | −0.0032 (10) | −0.0025 (8) | −0.0144 (11) |
O4 | 0.0374 (12) | 0.135 (3) | 0.0259 (12) | −0.0068 (15) | 0.0072 (10) | −0.0328 (14) |
O5 | 0.0383 (11) | 0.0570 (14) | 0.0196 (10) | 0.0076 (10) | 0.0051 (9) | 0.0051 (9) |
O6 | 0.0298 (11) | 0.0700 (16) | 0.0234 (11) | 0.0086 (10) | −0.0049 (8) | 0.0051 (10) |
O7 | 0.0200 (10) | 0.120 (2) | 0.0282 (11) | −0.0045 (12) | −0.0004 (9) | 0.0217 (14) |
O8 | 0.0331 (12) | 0.129 (3) | 0.0284 (12) | −0.0190 (14) | −0.0113 (9) | 0.0305 (14) |
O9 | 0.0404 (13) | 0.0364 (13) | 0.0692 (17) | 0.0016 (10) | −0.0271 (12) | −0.0001 (12) |
O10 | 0.0490 (8) | 0.0467 (8) | 0.0511 (8) | 0.0002 (6) | 0.0005 (6) | 0.0001 (6) |
C1 | 0.0294 (14) | 0.0336 (15) | 0.0234 (14) | 0.0049 (11) | 0.0006 (11) | −0.0010 (11) |
C2 | 0.0279 (13) | 0.0346 (15) | 0.0153 (12) | 0.0014 (11) | 0.0011 (10) | −0.0032 (11) |
C3 | 0.0222 (12) | 0.0388 (15) | 0.0213 (13) | −0.0018 (11) | −0.0021 (10) | −0.0026 (11) |
C4 | 0.0235 (14) | 0.063 (2) | 0.0249 (14) | −0.0066 (13) | 0.0042 (11) | −0.0097 (14) |
C5 | 0.0331 (15) | 0.059 (2) | 0.0197 (13) | −0.0068 (14) | 0.0023 (11) | −0.0089 (13) |
C6 | 0.0288 (15) | 0.071 (2) | 0.0233 (15) | −0.0037 (14) | −0.0057 (12) | −0.0128 (14) |
C7 | 0.0222 (13) | 0.065 (2) | 0.0281 (15) | 0.0025 (14) | −0.0004 (11) | −0.0082 (15) |
C8 | 0.0316 (14) | 0.0402 (16) | 0.0212 (13) | 0.0064 (12) | 0.0003 (11) | −0.0006 (11) |
C9 | 0.0274 (13) | 0.0453 (17) | 0.0211 (13) | 0.0005 (12) | 0.0003 (11) | 0.0032 (12) |
C10 | 0.0210 (13) | 0.061 (2) | 0.0251 (14) | −0.0028 (13) | −0.0016 (11) | 0.0046 (13) |
C11 | 0.0273 (15) | 0.086 (3) | 0.0211 (14) | −0.0115 (16) | −0.0002 (11) | 0.0129 (15) |
C12 | 0.0337 (16) | 0.074 (2) | 0.0219 (15) | −0.0074 (15) | −0.0075 (12) | 0.0116 (15) |
C13 | 0.0219 (15) | 0.094 (3) | 0.0345 (18) | −0.0077 (16) | −0.0028 (12) | 0.0161 (18) |
C14 | 0.0253 (14) | 0.073 (2) | 0.0253 (15) | −0.0031 (15) | 0.0042 (11) | 0.0111 (15) |
Cd1—O9 | 2.196 (2) | O10—H101 | 0.809 (10) |
Cd1—O10 | 2.268 (3) | O10—H102 | 0.798 (10) |
Cd1—O6 | 2.327 (2) | C1—C2 | 1.469 (4) |
Cd1—O2 | 2.364 (2) | C2—C7 | 1.396 (4) |
Cd1—O3i | 2.397 (2) | C2—C3 | 1.398 (4) |
Cd1—O5 | 2.428 (2) | C3—C4 | 1.378 (4) |
Cd1—O1 | 2.459 (2) | C4—C5 | 1.377 (4) |
O1—C1 | 1.270 (3) | C4—H4 | 0.9300 |
O2—C1 | 1.278 (4) | C5—C6 | 1.387 (4) |
O3—C3 | 1.367 (3) | C6—C7 | 1.370 (4) |
O3—Cd1ii | 2.397 (2) | C6—H6 | 0.9300 |
O3—H31 | 0.80 (5) | C7—H7A | 0.9300 |
O4—C5 | 1.352 (3) | C8—C9 | 1.470 (4) |
O4—H4A | 0.8200 | C9—C14 | 1.391 (4) |
O5—C8 | 1.260 (3) | C9—C10 | 1.403 (4) |
O6—C8 | 1.270 (3) | C10—C11 | 1.379 (4) |
O7—C10 | 1.356 (3) | C11—C12 | 1.373 (4) |
O7—H7 | 0.8200 | C11—H11 | 0.9300 |
O8—C12 | 1.366 (3) | C12—C13 | 1.386 (4) |
O8—H8 | 0.8200 | C13—C14 | 1.372 (4) |
O9—H91 | 0.813 (10) | C13—H13 | 0.9300 |
O9—H92 | 0.812 (10) | C14—H14 | 0.9300 |
O9—Cd1—O10 | 177.80 (9) | C7—C2—C1 | 120.8 (2) |
O9—Cd1—O6 | 93.31 (9) | C3—C2—C1 | 121.3 (2) |
O10—Cd1—O6 | 86.65 (9) | O3—C3—C4 | 118.6 (2) |
O9—Cd1—O2 | 98.31 (9) | O3—C3—C2 | 120.4 (2) |
O10—Cd1—O2 | 81.31 (8) | C4—C3—C2 | 121.0 (2) |
O6—Cd1—O2 | 163.85 (8) | C5—C4—C3 | 119.5 (3) |
O9—Cd1—O3i | 83.02 (9) | C5—C4—H4 | 120.3 |
O10—Cd1—O3i | 94.78 (9) | C3—C4—H4 | 120.3 |
O6—Cd1—O3i | 91.19 (7) | O4—C5—C4 | 117.4 (3) |
O2—Cd1—O3i | 79.20 (7) | O4—C5—C6 | 121.7 (3) |
O9—Cd1—O5 | 92.35 (8) | C4—C5—C6 | 120.9 (3) |
O10—Cd1—O5 | 89.42 (8) | C7—C6—C5 | 119.2 (3) |
O6—Cd1—O5 | 54.63 (7) | C7—C6—H6 | 120.4 |
O2—Cd1—O5 | 135.39 (7) | C5—C6—H6 | 120.4 |
O3i—Cd1—O5 | 145.31 (7) | C6—C7—C2 | 121.5 (3) |
O9—Cd1—O1 | 97.43 (9) | C6—C7—H7A | 119.2 |
O10—Cd1—O1 | 84.11 (8) | C2—C7—H7A | 119.2 |
O6—Cd1—O1 | 135.35 (7) | O5—C8—O6 | 119.3 (3) |
O2—Cd1—O1 | 54.13 (7) | O5—C8—C9 | 121.8 (3) |
O3i—Cd1—O1 | 133.03 (7) | O6—C8—C9 | 118.9 (2) |
O5—Cd1—O1 | 81.64 (7) | O5—C8—Cd1 | 61.99 (15) |
C1—O1—Cd1 | 90.81 (17) | O6—C8—Cd1 | 57.45 (14) |
C1—O2—Cd1 | 94.99 (17) | C9—C8—Cd1 | 174.7 (2) |
C3—O3—Cd1ii | 134.54 (17) | C14—C9—C10 | 117.4 (2) |
C3—O3—H31 | 106 (3) | C14—C9—C8 | 121.8 (2) |
Cd1ii—O3—H31 | 120 (3) | C10—C9—C8 | 120.7 (3) |
C5—O4—H4A | 109.5 | O7—C10—C11 | 117.6 (2) |
C8—O5—Cd1 | 90.73 (17) | O7—C10—C9 | 121.9 (2) |
C8—O6—Cd1 | 95.15 (17) | C11—C10—C9 | 120.5 (3) |
C10—O7—H7 | 109.5 | C12—C11—C10 | 120.3 (3) |
C12—O8—H8 | 109.5 | C12—C11—H11 | 119.9 |
Cd1—O9—H91 | 118.1 (18) | C10—C11—H11 | 119.9 |
Cd1—O9—H92 | 128.9 (19) | O8—C12—C11 | 116.5 (3) |
H91—O9—H92 | 110.9 (17) | O8—C12—C13 | 122.8 (3) |
Cd1—O10—H101 | 121 (2) | C11—C12—C13 | 120.7 (3) |
Cd1—O10—H102 | 101 (2) | C14—C13—C12 | 118.6 (3) |
H101—O10—H102 | 114.2 (18) | C14—C13—H13 | 120.7 |
O1—C1—O2 | 119.1 (3) | C12—C13—H13 | 120.7 |
O1—C1—C2 | 119.9 (2) | C13—C14—C9 | 122.5 (3) |
O2—C1—C2 | 121.0 (2) | C13—C14—H14 | 118.8 |
C7—C2—C3 | 117.9 (2) | C9—C14—H14 | 118.8 |
Symmetry codes: (i) x+1/2, −y+1/2, −z+1; (ii) x−1/2, −y+1/2, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H31···O1 | 0.80 (5) | 1.80 (5) | 2.536 (3) | 154 (5) |
O4—H4A···O8iii | 0.82 | 1.96 | 2.775 (3) | 173 |
O7—H7···O6 | 0.82 | 1.81 | 2.535 (3) | 147 |
O8—H8···O7iv | 0.82 | 1.99 | 2.732 (3) | 151 |
O9—H91···O2v | 0.81 (1) | 1.93 (1) | 2.738 (3) | 175 (3) |
O9—H92···O5vi | 0.81 (1) | 1.90 (1) | 2.706 (3) | 175 (3) |
O10—H101···O2vii | 0.81 (1) | 2.07 (2) | 2.855 (3) | 162 (3) |
Symmetry codes: (iii) −x+3/2, −y+1, z+1/2; (iv) x−1/2, y, −z+1/2; (v) −x+2, −y, −z+1; (vi) −x+3/2, y−1/2, z; (vii) −x+2, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | [Cd(C7H5O4)2(H2O)2] |
Mr | 454.65 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 292 |
a, b, c (Å) | 11.964 (2), 7.7882 (16), 33.893 (7) |
V (Å3) | 3158.1 (11) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 1.44 |
Crystal size (mm) | 0.35 × 0.20 × 0.04 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2001) |
Tmin, Tmax | 0.633, 0.945 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 19791, 3063, 2847 |
Rint | 0.036 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.029, 0.069, 1.05 |
No. of reflections | 3063 |
No. of parameters | 248 |
No. of restraints | 18 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.48, −0.47 |
Computer programs: SMART (Bruker, 2001), SMART-Plus (Bruker, 2001), SAINT-Plus, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), PLATON.
Cd1—O9 | 2.196 (2) | Cd1—O3i | 2.397 (2) |
Cd1—O10 | 2.268 (3) | Cd1—O5 | 2.428 (2) |
Cd1—O6 | 2.327 (2) | Cd1—O1 | 2.459 (2) |
Cd1—O2 | 2.364 (2) |
Symmetry code: (i) x+1/2, −y+1/2, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H31···O1 | 0.80 (5) | 1.80 (5) | 2.536 (3) | 154 (5) |
O4—H4A···O8ii | 0.82 | 1.96 | 2.775 (3) | 173 |
O7—H7···O6 | 0.82 | 1.81 | 2.535 (3) | 147 |
O8—H8···O7iii | 0.82 | 1.99 | 2.732 (3) | 151 |
O9—H91···O2iv | 0.813 (10) | 1.928 (11) | 2.738 (3) | 175 (3) |
O9—H92···O5v | 0.812 (10) | 1.896 (10) | 2.706 (3) | 175 (3) |
O10—H101···O2vi | 0.809 (10) | 2.074 (15) | 2.855 (3) | 162 (3) |
Symmetry codes: (ii) −x+3/2, −y+1, z+1/2; (iii) x−1/2, y, −z+1/2; (iv) −x+2, −y, −z+1; (v) −x+3/2, y−1/2, z; (vi) −x+2, −y+1, −z+1. |
Design and synthesis of metal coordination polymers based on benzene carboxylates have been attracting chemist's interests and constitutes an important area of research (Thirumurugan & Natarajan, 2004). During the past years, lots of novel benzene multicarboxylates base compounds have been reported (Tao et al., 2000; Zhang et al., 2005). However, in those reported literatures, the common features tried to construct predictable one-, two, three-dimensional coordination networks by changing the numbers or relative position of carboxylates. In contrast, benzene carboxylates containing the hydroxyl can be utilized to coordinate to metal ions and generate unusual structures have never been reported. Herein, we report the title compound (I).
The title compound (I) present a one-dimensional chain [Cd(C7O4H5)2(H2O)2]n, in which Cd2+ is coordinated by four oxygen atoms from two 2,4-dihydroxybenzoate anion, two water molecules, and one oxygen from the hydroxyl of another 2,4-dihydroxybenzoate anion. The environment of Cd ion is in a distorted pentagonal bipyramid (Fig. 1). In the equatorial plane, Cd1 ion is coordinated by four carboxylates oxygen (O1, O2, O5, O6) and one oxygen (O3b) of the hydroxyl. The Cd1—O distances range from 2.327 (2) to 2.459 (2)Å (Table 1). The mean deviation from the equatorial plane is 0.129 Å. The axial sites are occupied by two water oxygen atoms (O9 and O10) with Cd1—O lengths ranging from 2.196 (2) to 2.268 (3)Å (Table 1). The obvious differences of Cd1—O length show that the water more greatly interact with the Cd2+ ion than that of the carboxylate. The axial O9—Cd1—O10 bond angle is 177.80 (9) Å.
In addition, the intra-molecular hydrogen bonds exhibit in the compound, O7—H7 and O3—H31 acting as hydrogen bond donor, and O6 and O1 as hydrogen bond acceptor, constructing two S(6) rings (Fig. 1, Table 2). These units are linked into a one-dimensional chain-like structure by the hydroxyl oxygen atom O3 (Fig. 2).