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Acta Cryst. (2009). E65, m167-m168    [ doi:10.1107/S1600536808044267 ]

catena-Poly[[diaquacalcium(II)]-di-[mu]-2-chloronicotinato]

L. Quan, H. Yin, L. Cui and M. Yang

Abstract top

The itle compound, [Ca(C6H3ClNO2)2(H2O)2]n, contains polymeric chains extending along [100] that are generated by inversion centres. The Ca2+ ions are bridged by 2-chloronicotinate groups and exhibit an eight-coordination by six carboxylate O atoms of four different 2-chloronicotinate ligands and two O atoms of water molecules. In the crystal structure, intermolecular O-H...O, O-H...N and C-H...O hydrogen bonds result in the formation of a supramolecular network structure. The [pi]-[pi] contacts between the 2-chloronicotinate rings [centroid-centroid distances = 3.875 (3) and 3.701 (3) Å] may further stabilize the structure.

Comment top

Chemistry of alkaline earth metals is an unexplored area. The model complexes containing Mg2+ and Ca2+ cations have previously been prepared and used as probes for understanding the binding modes of these metals (Schmidbaur et al., 1989, 1990). In our ongoing studies with 2-chloronicotinate ligand and s-block metal ions, the title compound has been synthesized, and we report herein its crystal structure.

In the molecule of the title compound, (I), (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. It has an inversion centre midway between the two CaII ions, which are bridged by 2-chloronicotinate groups. Each Ca atom is eight-coordinated by six O atoms of 2-chloronicotinate ligands and two O atoms of water molecules. It essentially forms a one-dimensional chain structure (Fig. 2). The Ca—O bonds are in the range of [2.366 (3)–2.734 (3) Å] (Table 1). The average value of the Ca—O bonds [2.467 (3) Å] is almost the same with the corresponding values [2.4674 (9) Å] in [Ca(3-aba)2(H2O)2]n (where 3-aba is 3-aminobenzoic acid), (II) (Murugavel & Banerjee, 2003) and [2.4556 (8) Å] in [Ca(H2O)3Ca(1,3-pdta)- (H2O)]. 2(H2O) (where 1,3-pdta is the 1,3-propanediaminetetraacetate ion), (III) (Radanovic et al., 2004). The Ca1—Ca1i [4.0553 (14) Å] and Ca1—Ca1ii [4.0681 (14) Å] [symmetry codes: (i) 1 - x, -y, 1 - z, (ii) 2 - x, -y, 1 - z] distances are longer than the corresponding value [4.0034 (5) Å] in (II).

In the crystal structure, intermolecular O—H···O, O—H···N and C—H···O hydrogen bonds (Table 2) result in the formation of a supramolecular network structure. The π–π contacts between the 2-chloronicotinate rings, Cg1–Cg1i and Cg2–Cg2ii [symmetry codes: (i) -x, 2 - y, -z; (ii) 1 - x, 1 - y, 1 - z, where Cg1 and Cg2 are centroids of the rings A (N1/C2–C6) and B (N2/C8–C12), respectively] may further stabilize the structure, with centroid–centroid distances of 3.875 (3) Å and 3.701 (3) Å.

Related literature top

For general background, see: Schmidbaur et al. (1989, 1990). For related structures, see: Murugavel & Banerjee (2003); Radanovic et al. (2004). For bond-length data, see: Allen et al. (1987).

Experimental top

For the preparation of the title compound, CaCl2(H2O)2 (0.588 g, 4 mmol) and 2-chloronicotinic acid (0.044 g, 0.4 mmol) were dissolved in H2O (20 ml) and MeOH (30 ml) by refluxing for 30 min. Sodium methoxide (0.4 mmol, 0.8 ml) was added dropwise by stirring. After refluxing for 8 h, the colorless solution was obtained, and then filtered. The solvent was gradually removed by evaporation under vacuum until the colorless solid was obtained, which was recrystallized from petroleum ether–dichoromethane (1:1) to give the block-shaped colorless crystals.

Refinement top

H atoms were positioned geometrically, with O—H = 0.85 Å (for H2O) and C—H = 0.93 Å for aromatic H, respectively, and constrained to ride on their parent atoms with Uiso(H) = 1.2Ueq(C,O).

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. A partial packing diagram of the title compound, showing the formation of the one dimensional chain structure.
catena-Poly[[diaquacalcium(II)]-di-µ-2-chloronicotinato] top
Crystal data top
[Ca(C6H3ClNO2)2(H2O)2]Z = 2
Mr = 389.20F(000) = 396
Triclinic, P1Dx = 1.442 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.8363 (10) ÅCell parameters from 2126 reflections
b = 10.8421 (16) Åθ = 2.5–27.6°
c = 10.8834 (16) ŵ = 0.68 mm−1
α = 98.455 (2)°T = 298 K
β = 97.610 (1)°Block, colourless
γ = 97.289 (1)°0.48 × 0.40 × 0.30 mm
V = 896.4 (2) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer		3074 independent reflections
Radiation source: fine-focus sealed tube2306 reflections with I > 2σ(I)
graphiteRint = 0.022
φ and ω scansθmax = 25.0°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −9→9
Tmin = 0.738, Tmax = 0.823k = −11→12
4594 measured reflectionsl = −11→12
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.145H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.072P)2 + 0.8771P]
where P = (Fo2 + 2Fc2)/3
3074 reflections(Δ/σ)max = 0.001
208 parametersΔρmax = 0.47 e Å−3
0 restraintsΔρmin = −0.45 e Å−3
Crystal data top
[Ca(C6H3ClNO2)2(H2O)2]γ = 97.289 (1)°
Mr = 389.20V = 896.4 (2) Å3
Triclinic, P1Z = 2
a = 7.8363 (10) ÅMo Kα radiation
b = 10.8421 (16) ŵ = 0.68 mm−1
c = 10.8834 (16) ÅT = 298 K
α = 98.455 (2)°0.48 × 0.40 × 0.30 mm
β = 97.610 (1)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		3074 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2306 reflections with I > 2σ(I)
Tmin = 0.738, Tmax = 0.823Rint = 0.022
4594 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.043H-atom parameters constrained
wR(F2) = 0.145Δρmax = 0.47 e Å−3
S = 1.03Δρmin = −0.45 e Å−3
3074 reflectionsAbsolute structure: ?
208 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Ca10.75350 (8)−0.02117 (7)0.54151 (6)0.0273 (2)
Cl11.31442 (17)−0.08155 (14)0.89399 (12)0.0688 (4)
Cl20.85580 (16)0.45842 (12)0.62037 (12)0.0642 (4)
N11.2104 (5)0.0770 (5)1.0606 (3)0.0597 (11)
N20.7024 (5)0.5552 (3)0.4414 (4)0.0521 (9)
O11.0474 (3)0.0510 (2)0.6352 (2)0.0363 (6)
O21.3309 (3)0.1026 (3)0.6846 (2)0.0468 (7)
O30.8087 (3)0.1815 (3)0.4807 (3)0.0501 (8)
O40.5271 (3)0.1368 (3)0.4706 (3)0.0447 (7)
O50.8604 (3)−0.2084 (2)0.5835 (2)0.0395 (6)
H5B0.9605−0.20920.56170.047*
H5C0.7926−0.27220.54100.047*
O60.6803 (4)0.0628 (3)0.7404 (3)0.0539 (8)
H6B0.70600.01640.79460.065*
H6C0.57210.06720.73400.065*
C11.1815 (5)0.0877 (4)0.7134 (3)0.0336 (8)
C21.2213 (5)0.0517 (4)0.9394 (4)0.0447 (10)
C31.1612 (5)0.1197 (4)0.8500 (3)0.0392 (9)
C41.0797 (6)0.2201 (5)0.8907 (4)0.0574 (12)
H41.03300.26770.83390.069*
C51.0684 (7)0.2488 (6)1.0167 (5)0.0694 (15)
H51.01680.31761.04620.083*
C61.1333 (6)0.1758 (6)1.0973 (4)0.0644 (14)
H61.12350.19571.18190.077*
C70.6592 (5)0.2077 (3)0.4592 (4)0.0335 (8)
C80.7209 (5)0.4468 (4)0.4786 (4)0.0404 (9)
C90.6374 (4)0.3299 (3)0.4140 (4)0.0334 (8)
C100.5307 (5)0.3306 (4)0.3029 (4)0.0491 (11)
H100.46960.25530.25660.059*
C110.5145 (6)0.4422 (5)0.2605 (5)0.0595 (13)
H110.44540.44300.18440.071*
C120.6014 (6)0.5528 (5)0.3319 (5)0.0598 (13)
H120.58960.62830.30310.072*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ca10.0220 (4)0.0305 (4)0.0307 (4)0.0046 (3)0.0048 (3)0.0083 (3)
Cl10.0708 (8)0.0885 (10)0.0633 (8)0.0386 (7)0.0216 (6)0.0320 (7)
Cl20.0589 (7)0.0549 (7)0.0694 (8)0.0096 (6)−0.0128 (6)−0.0008 (6)
N10.040 (2)0.105 (3)0.033 (2)0.008 (2)0.0044 (16)0.013 (2)
N20.042 (2)0.0327 (19)0.083 (3)0.0083 (16)0.0124 (19)0.0121 (18)
O10.0253 (13)0.0476 (16)0.0334 (14)0.0041 (11)0.0003 (11)0.0036 (12)
O20.0246 (14)0.077 (2)0.0374 (15)0.0034 (13)0.0070 (11)0.0061 (14)
O30.0299 (15)0.0408 (16)0.088 (2)0.0111 (12)0.0138 (14)0.0274 (15)
O40.0327 (15)0.0402 (15)0.0632 (19)−0.0010 (12)0.0142 (13)0.0149 (13)
O50.0300 (14)0.0340 (14)0.0570 (17)0.0060 (11)0.0099 (12)0.0119 (12)
O60.0371 (16)0.089 (2)0.0397 (16)0.0195 (15)0.0091 (13)0.0113 (15)
C10.031 (2)0.041 (2)0.0295 (19)0.0066 (16)0.0028 (16)0.0084 (16)
C20.031 (2)0.070 (3)0.034 (2)0.0077 (19)0.0065 (16)0.009 (2)
C30.0250 (19)0.057 (3)0.033 (2)0.0035 (17)0.0048 (16)0.0027 (18)
C40.060 (3)0.068 (3)0.045 (3)0.017 (2)0.011 (2)0.005 (2)
C50.064 (3)0.088 (4)0.053 (3)0.019 (3)0.018 (3)−0.012 (3)
C60.048 (3)0.104 (4)0.036 (3)0.004 (3)0.012 (2)−0.005 (3)
C70.0277 (19)0.0288 (19)0.045 (2)0.0062 (15)0.0093 (16)0.0057 (16)
C80.030 (2)0.034 (2)0.059 (3)0.0058 (16)0.0092 (18)0.0109 (18)
C90.0230 (18)0.033 (2)0.047 (2)0.0064 (15)0.0110 (16)0.0109 (17)
C100.043 (2)0.044 (2)0.060 (3)0.0105 (19)0.001 (2)0.009 (2)
C110.067 (3)0.057 (3)0.056 (3)0.019 (2)−0.005 (2)0.020 (2)
C120.056 (3)0.048 (3)0.082 (4)0.014 (2)0.010 (3)0.029 (3)
Geometric parameters (Å, °) top
Ca1—O4i2.366 (3)O4—C71.241 (4)
Ca1—O52.373 (3)O4—Ca1i2.366 (3)
Ca1—O12.375 (2)O5—H5B0.8499
Ca1—O32.391 (3)O5—H5C0.8500
Ca1—O62.393 (3)O6—H6B0.8501
Ca1—O2ii2.461 (3)O6—H6C0.8500
Ca1—O1ii2.641 (3)C1—C31.511 (5)
Ca1—O42.734 (3)C1—Ca1ii2.890 (4)
Ca1—C1ii2.890 (4)C2—C31.375 (6)
Ca1—Ca1i4.0553 (14)C3—C41.377 (6)
Ca1—Ca1ii4.0681 (14)C4—C51.378 (6)
Ca1—H5B2.7769C4—H40.9300
Ca1—H5C2.7764C5—C61.357 (8)
Cl1—C21.737 (5)C5—H50.9300
Cl2—C81.729 (4)C6—H60.9300
N1—C21.323 (5)C7—C91.501 (5)
N1—C61.332 (7)C8—C91.391 (5)
N2—C81.317 (5)C9—C101.378 (5)
N2—C121.336 (6)C10—C111.372 (6)
O1—C11.242 (4)C10—H100.9300
O1—Ca1ii2.641 (3)C11—C121.372 (7)
O2—C11.248 (4)C11—H110.9300
O2—Ca1ii2.461 (3)C12—H120.9300
O3—C71.241 (4)
O4i—Ca1—O585.90 (9)O5—Ca1—H5C16.8
O4i—Ca1—O1154.07 (10)O1—Ca1—H5C92.6
O5—Ca1—O176.49 (9)O3—Ca1—H5C155.0
O4i—Ca1—O3124.46 (9)O6—Ca1—H5C108.6
O5—Ca1—O3148.15 (9)O2ii—Ca1—H5C80.4
O1—Ca1—O377.33 (9)O1ii—Ca1—H5C80.4
O4i—Ca1—O679.48 (10)O4—Ca1—H5C144.2
O5—Ca1—O6102.23 (10)C1ii—Ca1—H5C80.4
O1—Ca1—O685.76 (9)Ca1i—Ca1—H5C111.8
O3—Ca1—O693.57 (11)Ca1ii—Ca1—H5C85.3
O4i—Ca1—O2ii76.74 (9)H5B—Ca1—H5C28.7
O5—Ca1—O2ii93.19 (10)C2—N1—C6116.7 (4)
O1—Ca1—O2ii122.53 (9)C8—N2—C12117.9 (4)
O3—Ca1—O2ii85.84 (11)C1—O1—Ca1162.8 (2)
O6—Ca1—O2ii150.55 (10)C1—O1—Ca1ii88.6 (2)
O4i—Ca1—O1ii124.14 (9)Ca1—O1—Ca1ii108.26 (9)
O5—Ca1—O1ii80.03 (9)C1—O2—Ca1ii96.9 (2)
O1—Ca1—O1ii71.74 (9)C7—O3—Ca1101.6 (2)
O3—Ca1—O1ii74.78 (9)C7—O4—Ca1i168.0 (3)
O6—Ca1—O1ii156.33 (9)C7—O4—Ca185.3 (2)
O2ii—Ca1—O1ii50.80 (8)Ca1i—O4—Ca1105.13 (10)
O4i—Ca1—O474.87 (10)Ca1—O5—H5B109.6
O5—Ca1—O4160.24 (9)Ca1—O5—H5C109.6
O1—Ca1—O4123.16 (9)H5B—O5—H5C108.3
O3—Ca1—O449.89 (8)Ca1—O6—H6B110.5
O6—Ca1—O479.04 (9)Ca1—O6—H6C110.5
O2ii—Ca1—O478.19 (10)H6B—O6—H6C108.8
O1ii—Ca1—O4106.86 (8)O1—C1—O2123.5 (3)
O4i—Ca1—C1ii100.91 (10)O1—C1—C3117.9 (3)
O5—Ca1—C1ii87.26 (10)O2—C1—C3118.5 (3)
O1—Ca1—C1ii97.14 (10)O1—C1—Ca1ii65.98 (19)
O3—Ca1—C1ii78.32 (11)O2—C1—Ca1ii57.69 (19)
O6—Ca1—C1ii170.49 (11)C3—C1—Ca1ii175.5 (3)
O2ii—Ca1—C1ii25.39 (9)N1—C2—C3125.2 (4)
O1ii—Ca1—C1ii25.45 (9)N1—C2—Cl1115.4 (3)
O4—Ca1—C1ii91.86 (9)C3—C2—Cl1119.4 (3)
O4i—Ca1—Ca1i40.60 (7)C2—C3—C4116.7 (4)
O5—Ca1—Ca1i126.35 (7)C2—C3—C1122.6 (4)
O1—Ca1—Ca1i153.30 (7)C4—C3—C1120.7 (4)
O3—Ca1—Ca1i84.02 (7)C3—C4—C5119.0 (5)
O6—Ca1—Ca1i76.43 (7)C3—C4—H4120.5
O2ii—Ca1—Ca1i74.23 (6)C5—C4—H4120.5
O1ii—Ca1—Ca1i121.53 (6)C6—C5—C4119.5 (5)
O4—Ca1—Ca1i34.28 (5)C6—C5—H5120.3
C1ii—Ca1—Ca1i97.60 (7)C4—C5—H5120.3
O4i—Ca1—Ca1ii152.81 (8)N1—C6—C5122.9 (4)
O5—Ca1—Ca1ii75.59 (6)N1—C6—H6118.5
O1—Ca1—Ca1ii38.06 (6)C5—C6—H6118.5
O3—Ca1—Ca1ii72.63 (7)O3—C7—O4123.2 (3)
O6—Ca1—Ca1ii123.46 (8)O3—C7—C9118.2 (3)
O2ii—Ca1—Ca1ii84.47 (6)O4—C7—C9118.6 (3)
O1ii—Ca1—Ca1ii33.68 (5)N2—C8—C9124.5 (4)
O4—Ca1—Ca1ii120.51 (6)N2—C8—Cl2114.9 (3)
C1ii—Ca1—Ca1ii59.09 (7)C9—C8—Cl2120.6 (3)
Ca1i—Ca1—Ca1ii149.45 (4)C10—C9—C8116.3 (3)
O4i—Ca1—H5B101.0C10—C9—C7120.2 (3)
O5—Ca1—H5B16.8C8—C9—C7123.5 (3)
O1—Ca1—H5B64.9C11—C10—C9120.0 (4)
O3—Ca1—H5B131.5C11—C10—H10120.0
O6—Ca1—H5B111.9C9—C10—H10120.0
O2ii—Ca1—H5B89.7C10—C11—C12119.2 (4)
O1ii—Ca1—H5B65.5C10—C11—H11120.4
O4—Ca1—H5B167.8C12—C11—H11120.4
C1ii—Ca1—H5B77.5N2—C12—C11122.0 (4)
Ca1i—Ca1—H5B140.4N2—C12—H12119.0
Ca1ii—Ca1—H5B58.9C11—C12—H12119.0
O4i—Ca1—H5C72.5
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+2, −y, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O5—H5B···O3ii0.851.922.765 (3)171
O5—H5C···N2iii0.852.012.831 (3)162
O6—H6B···N1iv0.852.072.919 (4)173
O6—H6C···O2v0.852.002.826 (3)165
C6—H6···O5iv0.932.523.432 (4)166
Symmetry codes: (ii) −x+2, −y, −z+1; (iii) x, y−1, z; (iv) −x+2, −y, −z+2; (v) x−1, y, z.
Table 1
Selected geometric parameters (Å, °) top
Ca1—O4i2.366 (3)Ca1—O2ii2.461 (3)
Ca1—O52.373 (3)Ca1—O1ii2.641 (3)
Ca1—O12.375 (2)Ca1—O42.734 (3)
Ca1—O32.391 (3)Ca1—Ca1i4.0553 (14)
Ca1—O62.393 (3)Ca1—Ca1ii4.0681 (14)
O4i—Ca1—O585.90 (9)O4i—Ca1—O1ii124.14 (9)
O4i—Ca1—O1154.07 (10)O5—Ca1—O1ii80.03 (9)
O5—Ca1—O176.49 (9)O1—Ca1—O1ii71.74 (9)
O4i—Ca1—O3124.46 (9)O3—Ca1—O1ii74.78 (9)
O5—Ca1—O3148.15 (9)O6—Ca1—O1ii156.33 (9)
O1—Ca1—O377.33 (9)O2ii—Ca1—O1ii50.80 (8)
O4i—Ca1—O679.48 (10)O4i—Ca1—O474.87 (10)
O5—Ca1—O6102.23 (10)O5—Ca1—O4160.24 (9)
O1—Ca1—O685.76 (9)O1—Ca1—O4123.16 (9)
O4i—Ca1—O2ii76.74 (9)O3—Ca1—O449.89 (8)
O5—Ca1—O2ii93.19 (10)O6—Ca1—O479.04 (9)
O1—Ca1—O2ii122.53 (9)O2ii—Ca1—O478.19 (10)
O3—Ca1—O2ii85.84 (11)O1ii—Ca1—O4106.86 (8)
O6—Ca1—O2ii150.55 (10)
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+2, −y, −z+1.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O5—H5B···O3ii0.851.922.765 (3)171
O5—H5C···N2iii0.852.012.831 (3)162
O6—H6B···N1iv0.852.072.919 (4)173
O6—H6C···O2v0.852.002.826 (3)165
C6—H6···O5iv0.932.523.432 (4)166
Symmetry codes: (ii) −x+2, −y, −z+1; (iii) x, y−1, z; (iv) −x+2, −y, −z+2; (v) x−1, y, z.
Acknowledgements top

The authors acknowledge the National Natural Science Foundation of China (grant Nos. 20771053 and 20773059).

references
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