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Acta Cryst. (2007). E63, m2155-m2156    [ doi:10.1107/S1600536807033685 ]

catena-Poly[[[diaquacadmium(II)]-bis[[mu]-4-tert-butyl-2,6-bis(1,2,4-triazol-1-ylmethyl)phenol]] dinitrate dihydrate]

Z.-L. Chu, G. Xu, W. Huang and S.-H. Gou

Abstract top

The title compound, {[Cd(C16H20N6O)2(H2O)2](NO3)2·2H2O}n, contains a CdII atom, a 4-tert-butyl-2,6-bis(1,2,4- triazol-1-ylmethyl)phenol ligand (L), a nitrate anion and two water molecules in the asymmetric unit. The Cd atom resides on a crystallographic inversion centre, and the coordination about the Cd atom is distorted octahedral, formed by four equatorial N atoms from the triazole N atoms of four different L ligands [Cd-N = 2.295 (3) and 2.395 (3) Å] and the O atoms from two axial water molecules [Cd-O = 2.287 (3) Å]. Two Cd atoms with two L ligands form 24-membered M2L2 metallacycles along the a-axis direction, generating a double-stranded one-dimensional cationic chain. Inter- and intramolecular O-H...O/N hydrogen-bond interactions form a three-dimensional supramolecular network.

Comment top

In recent years, organic ligands with azole units have become a new class of supramolecular synthons of intense interest in creating appealing coordination polymers (Hoskins et al., 1997; Li et al., 2005). In our previous studies, we synthesized two kinds of flexible bidentate ligands 1,6-di(imidazole-1-yl-methyl)-4-R-phenol and 1,6-di(triazole-1-yl-methyl)-4-R-phenol (R = Me, t-Bu, or Cl), and demonstrated that they can form different structures and topologies with different metal ions (Ma et al., 2003; Zhu et al., 2004; Zhu et al., 2007). The title compound, (I), is obtained by the reaction of 1,6-di(triazole-1-yl-methyl)-4 - t-Bu-phenol(dttp) with cadmium nitrate in ethanol.

The asymmetric unit of (I) contains half a Cd(II) atom, one dttp ligand, two water molecules and a nitrate ion. The metal atoms are located on the crystallographic inversion center with octahedral geometry, formed equatorially by four N atoms of triazoles from four dttp ligands and axially by two O atoms from two water molecules (Fig. 1). Each dttp adopts a trans conformation in which two triazole groups of a ligand with a dihedral angle of 53.9 (3) ° are on the opposite direction of the central benzene ring. In this way two metal atoms and two dttp ligands form a 24-membered M2L2 macrocycle through Cd—N coordination bonds. In each macrocycle, two phenyl rings are found strictly in a plane and the intermetallic distance between the two CdII atoms is 11.96 (1) Å. Such a metallomacrocyclic unit repeats along the a-axis to generate a double-stranded one-dimensional cationic chain as shown in Fig. 2.

Each phenol O—H moiety is directed at the N atom of a triazole moiety with H···N distances ranging from 1.99 to 2.61 Å, indicative of strong intramolecular hydrogen-bonding interactions. It is noticed that the resulting one-dimensional chains are further linked together to a three-dimensional framework by the uncoordinated water molecules and nitrate anions through O–H···O, O–H···N and C–H···O hydrogen-bonding interactions as shown in Fig. 3.

Related literature top

For related literature, see: Hoskins et al. (1997); Ma et al. (2003); Yan et al. (1994); Zhu et al. (2004, 2007).

For related literature, see: Li et al. (2005).

Experimental top

All solvents and chemicals were of analytical grade and were used without further purification. Ligand dttp was prepared via a one-step Mannich reaction as a white powder in 57% yield (Yan et al., 1994). For the synthesis of (I), an ethanol solution (10 ml) of Cd(NO3)2.6H2O (34.4 mg, 0.1 mmol) was added slowly with constant stirring to a solution of dttp (31.2 mg, 0.1 mmol) in ethanol (30 ml) to give a clear solution. The reaction mixture was left to stand at room temperature for one week and colorless crystalline products were obtained (34.2 mg, 79%). Anal. Calcd. for C32H48CdN14O12: C, 43.84; H, 5.52; N, 22.37. Found: C, 41.18; H, 5.18; N, 21.01. Infra-red (KBr, cm-1): 3422(s), 3233(m), 2962(m), 1656(m), 1522(s).

Refinement top

All non-hydrogen atoms were refined anisotropically, whereas the positions of all H atoms were fixed geometrically and treated as riding atoms in the refinement with X—H distances set as follows: C–H 0.93–0.97 Å and O–H 0.82–0.85 Å.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Bruker, 2000); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound (I), showing 30% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. A perspective view of the one-dimensional cationic chain structure of (I) along the a-axis.
[Figure 3] Fig. 3. A three-dimensional packing diagram of (I). For clarity, only H atoms involved in hydrogen bonds are shown. Hydrogen-bond contacts are indicated by dashed lines.
catena-Poly[[[diaquacadmium(II)]-bis[µ-4-tert-butyl-2,6-bis(1,2,4- triazol-1-ylmethyl)phenol]] dinitrate dihydrate] top
Crystal data top
[Cd(C16H20N6O)2(H2O)2](NO3)2·2H2OF(000) = 964
Mr = 933.24Dx = 1.543 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 848 reflections
a = 11.960 (4) Åθ = 2.3–23.5°
b = 9.448 (3) ŵ = 0.62 mm−1
c = 18.756 (6) ÅT = 293 K
β = 108.592 (4)°Block, colorless
V = 2008.9 (11) Å30.35 × 0.30 × 0.20 mm
Z = 2
Data collection top
Bruker SMART CCD area-detector
diffractometer		3897 independent reflections
Radiation source: fine-focus sealed tube2974 reflections with I > 2σ(I)
graphiteRint = 0.031
φ and ω scansθmax = 26.0°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		h = −12→14
Tmin = 0.812, Tmax = 0.886k = −7→11
8433 measured reflectionsl = −22→23
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.107H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.047P)2]
where P = (Fo2 + 2Fc2)/3
3897 reflections(Δ/σ)max < 0.001
272 parametersΔρmax = 0.92 e Å−3
0 restraintsΔρmin = −0.46 e Å−3
Crystal data top
[Cd(C16H20N6O)2(H2O)2](NO3)2·2H2OV = 2008.9 (11) Å3
Mr = 933.24Z = 2
Monoclinic, P21/cMo Kα radiation
a = 11.960 (4) ŵ = 0.62 mm−1
b = 9.448 (3) ÅT = 293 K
c = 18.756 (6) Å0.35 × 0.30 × 0.20 mm
β = 108.592 (4)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		3897 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		2974 reflections with I > 2σ(I)
Tmin = 0.812, Tmax = 0.886Rint = 0.031
8433 measured reflectionsθmax = 26.0°
Refinement top
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.107Δρmax = 0.92 e Å−3
S = 1.08Δρmin = −0.46 e Å−3
3897 reflectionsAbsolute structure: ?
272 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Experimental. The structure was solved by direct methods (Bruker, 2000) and successive difference Fourier syntheses.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cd11.00000.50000.00000.03931 (14)
C10.4821 (3)0.1571 (4)0.07099 (17)0.0367 (8)
C20.4142 (3)0.0348 (3)0.05930 (19)0.0362 (8)
C30.4560 (3)−0.0813 (4)0.10476 (18)0.0389 (8)
H30.4097−0.16250.09710.047*
C40.5635 (3)−0.0817 (4)0.16110 (18)0.0389 (8)
C50.6286 (3)0.0425 (4)0.17102 (18)0.0394 (8)
H50.70150.04550.20850.047*
C60.5898 (3)0.1625 (3)0.12747 (17)0.0359 (7)
C70.6600 (3)0.2970 (4)0.14719 (19)0.0441 (9)
H7A0.60860.37150.15420.053*
H7B0.72190.28350.19480.053*
C80.8256 (3)0.3626 (4)0.0972 (2)0.0463 (9)
H80.88860.34220.14010.056*
C90.7236 (3)0.4264 (4)−0.0096 (2)0.0489 (9)
H90.70250.4610−0.05850.059*
C100.2986 (3)0.0280 (4)−0.0035 (2)0.0433 (9)
H10A0.30980.0617−0.04960.052*
H10B0.2725−0.0696−0.01130.052*
C110.1637 (3)0.2360 (4)−0.01451 (19)0.0452 (9)
H110.18450.2853−0.05130.054*
C120.0861 (3)0.1758 (4)0.0643 (2)0.0594 (11)
H120.03880.17710.09520.071*
C130.6105 (3)−0.2113 (4)0.21066 (18)0.0456 (9)
C140.5190 (4)−0.3283 (4)0.1967 (2)0.0707 (13)
H14A0.5023−0.36330.14640.106*
H14B0.4480−0.29150.20320.106*
H14C0.5489−0.40390.23180.106*
C150.6439 (4)−0.1696 (5)0.2937 (2)0.0679 (12)
H15A0.5759−0.13210.30380.102*
H15B0.7048−0.09900.30480.102*
H15C0.6720−0.25140.32460.102*
C160.7174 (4)−0.2704 (5)0.1931 (3)0.0804 (14)
H16A0.7468−0.35180.22400.121*
H16B0.7779−0.19940.20310.121*
H16C0.6948−0.29710.14100.121*
N10.7139 (2)0.3441 (3)0.09105 (15)0.0391 (7)
N20.6458 (2)0.3859 (3)0.02182 (16)0.0488 (8)
N30.8359 (2)0.4139 (3)0.03429 (16)0.0452 (7)
N40.2073 (2)0.1133 (3)0.01273 (14)0.0390 (7)
N50.1576 (3)0.0706 (4)0.06402 (18)0.0564 (8)
N60.0867 (2)0.2805 (3)0.01688 (16)0.0439 (7)
N70.9577 (4)0.0212 (6)0.2125 (3)0.0825 (13)
O10.43423 (19)0.2713 (2)0.02633 (14)0.0460 (6)
H10.48740.32150.02160.069*
O21.1054 (2)0.5603 (3)0.12084 (14)0.0670 (8)
H2A1.11970.64860.12530.080*
H2B1.06520.53260.14830.080*
O30.1714 (3)0.8280 (3)0.16290 (17)0.0990 (11)
H3B0.21530.85760.13830.149*
H3C0.11050.88020.15350.149*
O40.9864 (7)−0.0496 (6)0.2614 (3)0.239 (4)
O50.9399 (5)0.0037 (5)0.1480 (3)0.164 (3)
O60.9167 (5)0.1339 (7)0.2248 (4)0.178 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cd10.0348 (2)0.0368 (2)0.0502 (2)0.00473 (15)0.01896 (15)0.00747 (17)
C10.0419 (18)0.032 (2)0.0437 (18)0.0064 (15)0.0250 (15)0.0041 (15)
C20.0361 (17)0.032 (2)0.0462 (19)0.0023 (13)0.0206 (15)−0.0034 (14)
C30.0436 (19)0.031 (2)0.050 (2)0.0004 (15)0.0257 (16)−0.0005 (16)
C40.046 (2)0.033 (2)0.0445 (19)0.0035 (16)0.0247 (16)0.0019 (16)
C50.0402 (18)0.042 (2)0.0401 (18)0.0016 (15)0.0187 (15)0.0037 (15)
C60.0406 (18)0.034 (2)0.0409 (17)−0.0034 (14)0.0241 (15)−0.0016 (15)
C70.050 (2)0.041 (2)0.049 (2)−0.0056 (16)0.0279 (17)−0.0027 (17)
C80.0394 (19)0.049 (2)0.050 (2)−0.0010 (16)0.0137 (16)0.0048 (18)
C90.044 (2)0.052 (3)0.050 (2)−0.0069 (17)0.0143 (17)0.0138 (19)
C100.046 (2)0.036 (2)0.051 (2)0.0047 (15)0.0189 (16)−0.0055 (15)
C110.049 (2)0.038 (2)0.052 (2)0.0077 (16)0.0210 (17)0.0092 (17)
C120.059 (2)0.056 (3)0.080 (3)0.012 (2)0.046 (2)0.018 (2)
C130.055 (2)0.039 (2)0.048 (2)0.0038 (16)0.0224 (17)0.0107 (17)
C140.087 (3)0.046 (3)0.073 (3)−0.006 (2)0.016 (2)0.019 (2)
C150.087 (3)0.060 (3)0.053 (2)0.002 (2)0.018 (2)0.014 (2)
C160.080 (3)0.066 (3)0.110 (4)0.032 (2)0.051 (3)0.037 (3)
N10.0404 (15)0.0347 (17)0.0460 (16)−0.0040 (12)0.0190 (13)0.0022 (13)
N20.0390 (16)0.051 (2)0.0560 (18)−0.0041 (14)0.0148 (14)0.0149 (15)
N30.0421 (17)0.044 (2)0.0533 (17)−0.0008 (13)0.0206 (14)0.0075 (14)
N40.0381 (15)0.0352 (18)0.0442 (15)−0.0003 (12)0.0138 (12)−0.0010 (13)
N50.0540 (19)0.048 (2)0.079 (2)0.0102 (16)0.0372 (17)0.0191 (18)
N60.0391 (16)0.0387 (18)0.0575 (18)0.0058 (13)0.0205 (14)0.0071 (14)
N70.088 (3)0.090 (4)0.071 (3)0.004 (2)0.028 (2)0.010 (3)
O10.0433 (13)0.0332 (15)0.0646 (15)0.0034 (11)0.0215 (12)0.0128 (12)
O20.086 (2)0.0573 (18)0.0549 (16)0.0001 (16)0.0189 (15)0.0034 (14)
O30.118 (3)0.070 (2)0.100 (2)−0.0065 (19)0.022 (2)0.0237 (19)
O40.374 (10)0.121 (4)0.116 (4)0.077 (5)−0.069 (5)0.028 (3)
O50.171 (5)0.258 (7)0.079 (3)−0.079 (4)0.063 (3)−0.017 (3)
O60.169 (5)0.143 (5)0.242 (7)0.026 (4)0.093 (5)0.025 (5)
Geometric parameters (Å, °) top
Cd1—O2i2.287 (3)C11—N41.307 (4)
Cd1—O22.287 (3)C11—N61.311 (4)
Cd1—N6ii2.295 (3)C11—H110.9300
Cd1—N6iii2.295 (3)C12—N51.312 (5)
Cd1—N3i2.395 (3)C12—N61.332 (4)
Cd1—N32.395 (3)C12—H120.9300
C1—O11.374 (4)C13—C141.518 (5)
C1—C61.383 (4)C13—C161.524 (5)
C1—C21.389 (4)C13—C151.531 (5)
C2—C31.382 (5)C14—H14A0.9600
C2—C101.505 (5)C14—H14B0.9600
C3—C41.380 (4)C14—H14C0.9600
C3—H30.9300C15—H15A0.9600
C4—C51.387 (5)C15—H15B0.9600
C4—C131.532 (5)C15—H15C0.9600
C5—C61.388 (4)C16—H16A0.9600
C5—H50.9300C16—H16B0.9600
C6—C71.502 (4)C16—H16C0.9600
C7—N11.469 (4)N1—N21.353 (4)
C7—H7A0.9700N4—N51.343 (4)
C7—H7B0.9700N6—Cd1iv2.295 (3)
C8—N11.315 (4)N7—O41.099 (6)
C8—N31.318 (4)N7—O51.170 (6)
C8—H80.9300N7—O61.225 (6)
C9—N21.307 (4)O1—H10.8200
C9—N31.338 (4)O2—H2A0.8500
C9—H90.9300O2—H2B0.8500
C10—N41.465 (4)O3—H3B0.8500
C10—H10A0.9700O3—H3C0.8499
C10—H10B0.9700
O2i—Cd1—O2180.00 (8)N4—C11—H11124.5
O2i—Cd1—N6ii90.38 (10)N6—C11—H11124.5
O2—Cd1—N6ii89.62 (10)N5—C12—N6114.7 (3)
O2i—Cd1—N6iii89.62 (10)N5—C12—H12122.7
O2—Cd1—N6iii90.38 (10)N6—C12—H12122.7
N6ii—Cd1—N6iii180.0C14—C13—C16107.7 (3)
O2i—Cd1—N3i93.35 (10)C14—C13—C15107.6 (3)
O2—Cd1—N3i86.65 (10)C16—C13—C15110.5 (3)
N6ii—Cd1—N3i91.65 (10)C14—C13—C4111.9 (3)
N6iii—Cd1—N3i88.35 (10)C16—C13—C4109.4 (3)
O2i—Cd1—N386.65 (10)C15—C13—C4109.7 (3)
O2—Cd1—N393.35 (10)C13—C14—H14A109.5
N6ii—Cd1—N388.35 (10)C13—C14—H14B109.5
N6iii—Cd1—N391.65 (10)H14A—C14—H14B109.5
N3i—Cd1—N3180.00 (12)C13—C14—H14C109.5
O1—C1—C6122.9 (3)H14A—C14—H14C109.5
O1—C1—C2116.6 (3)H14B—C14—H14C109.5
C6—C1—C2120.4 (3)C13—C15—H15A109.5
C3—C2—C1119.0 (3)C13—C15—H15B109.5
C3—C2—C10120.7 (3)H15A—C15—H15B109.5
C1—C2—C10120.3 (3)C13—C15—H15C109.5
C4—C3—C2122.7 (3)H15A—C15—H15C109.5
C4—C3—H3118.7H15B—C15—H15C109.5
C2—C3—H3118.7C13—C16—H16A109.5
C3—C4—C5116.5 (3)C13—C16—H16B109.5
C3—C4—C13122.6 (3)H16A—C16—H16B109.5
C5—C4—C13120.9 (3)C13—C16—H16C109.5
C4—C5—C6123.0 (3)H16A—C16—H16C109.5
C4—C5—H5118.5H16B—C16—H16C109.5
C6—C5—H5118.5C8—N1—N2109.3 (3)
C1—C6—C5118.4 (3)C8—N1—C7130.0 (3)
C1—C6—C7122.0 (3)N2—N1—C7120.6 (3)
C5—C6—C7119.4 (3)C9—N2—N1102.7 (3)
N1—C7—C6114.7 (3)C8—N3—C9102.8 (3)
N1—C7—H7A108.6C8—N3—Cd1133.2 (2)
C6—C7—H7A108.6C9—N3—Cd1123.6 (2)
N1—C7—H7B108.6C11—N4—N5109.5 (3)
C6—C7—H7B108.6C11—N4—C10129.6 (3)
H7A—C7—H7B107.6N5—N4—C10120.8 (3)
N1—C8—N3110.6 (3)C12—N5—N4102.3 (3)
N1—C8—H8124.7C11—N6—C12102.4 (3)
N3—C8—H8124.7C11—N6—Cd1iv125.4 (2)
N2—C9—N3114.6 (3)C12—N6—Cd1iv131.7 (2)
N2—C9—H9122.7O4—N7—O5133.1 (7)
N3—C9—H9122.7O4—N7—O6114.0 (7)
N4—C10—C2111.9 (3)O5—N7—O6111.5 (6)
N4—C10—H10A109.2C1—O1—H1109.5
C2—C10—H10A109.2Cd1—O2—H2A111.9
N4—C10—H10B109.2Cd1—O2—H2B106.5
C2—C10—H10B109.2H2A—O2—H2B112.2
H10A—C10—H10B107.9H3B—O3—H3C109.5
N4—C11—N6111.0 (3)
Symmetry codes: (i) −x+2, −y+1, −z; (ii) −x+1, −y+1, −z; (iii) x+1, y, z; (iv) x−1, y, z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.822.613.247 (4)135
O1—H1···N20.821.992.777 (4)161
C8—H8···O60.932.483.150 (8)129
O2—H2A···O3iii0.851.862.692 (4)164
O2—H2B···O4v0.852.132.951 (7)164
O2—H2B···O6v0.852.513.070 (7)124
O3—H3B···N5vi0.852.422.920 (5)118
O3—H3C···O5vii0.852.323.163 (7)169
C7—H7B···O3viii0.972.603.501 (5)155
C8—H8···O4v0.932.222.996 (7)140
C12—H12···O5iv0.932.413.149 (7)136
Symmetry codes: (iii) x+1, y, z; (v) −x+2, y+1/2, −z+1/2; (vi) x, y+1, z; (vii) x−1, y+1, z; (viii) −x+1, y−1/2, −z+1/2; (iv) x−1, y, z.
Table 1
Selected geometric parameters (Å, °) top
Cd1—O22.287 (3)Cd1—N32.395 (3)
Cd1—N6i2.295 (3)
O2—Cd1—N6ii89.62 (10)O2—Cd1—N393.35 (10)
O2—Cd1—N6i90.38 (10)N6ii—Cd1—N388.35 (10)
O2—Cd1—N3iii86.65 (10)N6i—Cd1—N391.65 (10)
Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y+1, −z; (iii) −x+2, −y+1, −z.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N10.822.613.247 (4)135
O1—H1···N20.821.992.777 (4)161
C8—H8···O60.932.483.150 (8)129
O2—H2A···O3i0.851.862.692 (4)164
O2—H2B···O4iv0.852.132.951 (7)164
O2—H2B···O6iv0.852.513.070 (7)124
O3—H3B···N5v0.852.422.920 (5)118
O3—H3C···O5vi0.852.323.163 (7)169
C7—H7B···O3vii0.972.603.501 (5)155
C8—H8···O4iv0.932.222.996 (7)140
C12—H12···O5viii0.932.413.149 (7)136
Symmetry codes: (i) x+1, y, z; (iv) −x+2, y+1/2, −z+1/2; (v) x, y+1, z; (vi) x−1, y+1, z; (vii) −x+1, y−1/2, −z+1/2; (viii) x−1, y, z.
Acknowledgements top

We are indebted to the National Natural Science Foundation of China (No. 20271026 and 20301009) for financial support.

references
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