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Acta Crystallogr Sect E Struct Rep Online. 2009 August 1; 65(Pt 8): m947.
Published online 2009 July 18. doi:  10.1107/S1600536809027767
PMCID: PMC2977128

Poly[[bis­[μ-1,4-bis­(3-pyridylmeth­yl)piperazine-κ2 N:N′]dichlorido­cadmium(II)] tetra­hydrate]

Abstract

In the title compound, {[CdCl2(C16H20N4)2]·4H2O}n, octa­hedrally coordinated CdII ions, situated on crystallographic inversion centres, bearing trans-disposed chloride ligands, are linked into (4,4)-grid coordination polymer layers by tethering 1,4-bis­(3-pyridylmeth­yl)piperazine ligands. The layers are aligned parallel to the (An external file that holds a picture, illustration, etc.
Object name is e-65-0m947-efi7.jpg01) crystal planes and aggregate by means of O—H(...)N, O—H(...)O and O—H(...)Cl hydrogen-bonding mechanisms imparted by cyclic water mol­ecule tetra­mers.

Related literature

For a cadmium succinate coordination polymer containing N,N′-bis­(4-pyridylmeth­yl)piperazine, see: Martin et al. (2009 [triangle]). For the preparation of N,N′-bis­(3-pyridylmeth­yl)piperazine, see: Pocic et al. (2005 [triangle]).

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Object name is e-65-0m947-scheme1.jpg

Experimental

Crystal data

  • [CdCl2(C16H20N4)2]·4H2O
  • M r = 792.08
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0m947-efi8.jpg
  • a = 10.3481 (2) Å
  • b = 13.9791 (2) Å
  • c = 12.7789 (2) Å
  • β = 92.4730 (10)°
  • V = 1846.84 (5) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.78 mm−1
  • T = 173 K
  • 0.38 × 0.35 × 0.19 mm

Data collection

  • Bruker APEXII diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.753, T max = 0.868
  • 16443 measured reflections
  • 3391 independent reflections
  • 3060 reflections with I > 2σ(I)
  • R int = 0.027

Refinement

  • R[F 2 > 2σ(F 2)] = 0.021
  • wR(F 2) = 0.055
  • S = 1.07
  • 3391 reflections
  • 226 parameters
  • 6 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.42 e Å−3
  • Δρmin = −0.23 e Å−3

Data collection: APEX2 (Bruker, 2006 [triangle]); cell refinement: SAINT (Bruker, 2006 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: CrystalMaker (Palmer, 2007 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809027767/lh2863sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809027767/lh2863Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

We gratefully acknowledge the American Chemical Society Petroleum Research Fund for funding this work.

supplementary crystallographic information

Comment

The title compound was prepared during an attempt to prepare a divalent cadmium coordination polymer containing both succinate and N,N'-di(3-pyridylmethyl)piperazine (3-bpmp) ligands. A cadmium succinate coordination polymer containing the isomeric N,N'-di(4-pyridylmethyl)piperazine (4-bpmp) ligand manifested the unique example of a 658 layered topology (Martin et al., 2009).

The asymmetric unit of the title compound (Fig. 1) contains a CdII ion on the crystallographic inversion centre, one chloro ligand, one 3-bpmp ligand, and two water molecules of crystallization. Operation of the crystallographic symmetry generates an octahedral {CdCl2N4} coordination environment, with trans disposed chloro ligands and four N atom donors from pyridyl groups of four different 3-bpmp ligands.

Each CdII ion is linked to four others through the tethering 3-bpmp ligands to construct (4,4)-grid [CdCl2(3-bpmp)2]n coordination polymer layers (Fig. 2) that are oriented parallel to the (1 0 1) crystal planes. The through-ligand Cd···Cd distances measure 10.658 (3) Å. The layers stack in an AAA pattern along the a crystal direction via hydrogen-bonding mechanisms provided by tetrameric water molecule aggregations (Fig. 3). Within a single coordination polymer layer, a water molecule (O1W) engages in O—H···N hydrogen-bonding with a piperazinyl N atom, and in turn with another water molecule of crystallization (O2W). Then, this second water molecule of crystallization provides O—H···Cl hydrogen-bonding to a chloro ligand. The water molecules of crystallization engage in mutual O—H···O hydrogen-bonding across the interlamellar regions to construct the cyclic water molecule tetramers.

Experimental

Cadmium chloride dihydrate and succinic acid were obtained commercially. N,N'-bis(3-pyridylmethyl)piperazine was prepared via a published procedure (Pocic, et al., 2005). A mixture of cadmium chloride dihydrate (81 mg, 0.37 mmol), succinic acid (44 mg, 0.37 mmol), N,N'-bis(3-pyridylmethyl)piperazine (99 mg, 0.37 mmol) and 10.0 g water (550 mmol) was placed into a 23 ml Teflon-lined Parr Acid Digestion bomb, which was then heated under autogenous pressure at 393 K for 48 h. The resulting yellowish solution was allowed to stand undisturbed at 293 K for 3 d. Large straw-colored crystals of the title compound were deposited.

Refinement

All H atoms bound to C atoms were placed in calculated positions, with C—H = 0.95 Å and refined in riding mode with Uiso = 1.2Ueq(C). The H atoms bound to water molecule O atoms were found in a difference Fourier map, restrained with O—H = 0.89 Å, and refined with Uiso = 1.2Ueq(O).

Figures

Fig. 1.
The expanded asymmetric unit of the title compound, showing 50% probability ellipsoids and atom numbering scheme. Hydrogen atom positions are shown as grey sticks. Color codes: violet Cd, green Cl, N blue, orange O, black C. Symmetry codes: (i) x+1/2, ...
Fig. 2.
A view of the (4,4)-grid coordination polymer layer in the title compound.
Fig. 3.
Stacking diagram of the title compound, viewed along the b crystal direction. Water molecule tetramers can be seen in the interlamellar regions.

Crystal data

[CdCl2(C16H20N4)2]·4H2OF(000) = 820
Mr = 792.08Dx = 1.424 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 16643 reflections
a = 10.3481 (2) Åθ = 2.2–25.4°
b = 13.9791 (2) ŵ = 0.78 mm1
c = 12.7789 (2) ÅT = 173 K
β = 92.473 (1)°Fragment, colourless
V = 1846.84 (5) Å30.38 × 0.35 × 0.19 mm
Z = 2

Data collection

Bruker APEXII diffractometer3391 independent reflections
Radiation source: fine-focus sealed tube3060 reflections with I > 2σ(I)
graphiteRint = 0.027
ω and [var phi] scansθmax = 25.4°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −12→12
Tmin = 0.753, Tmax = 0.868k = −15→16
16443 measured reflectionsl = −15→15

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.021Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.055H atoms treated by a mixture of independent and constrained refinement
S = 1.07w = 1/[σ2(Fo2) + (0.0261P)2 + 0.7641P] where P = (Fo2 + 2Fc2)/3
3391 reflections(Δ/σ)max = 0.001
226 parametersΔρmax = 0.42 e Å3
6 restraintsΔρmin = −0.23 e Å3

Special details

Experimental. The fragment used in the single-crystal diffraction experiment was cleaved from a very large prismatic crystal using a scalpel.
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)

xyzUiso*/Ueq
Cd10.00000.50000.50000.01972 (7)
Cl1−0.00576 (4)0.56521 (3)0.69090 (3)0.02753 (11)
O1W0.31111 (17)1.01315 (12)0.44201 (15)0.0498 (4)
H1WA0.267 (2)0.9840 (17)0.3915 (18)0.060*
H1WB0.375 (2)1.0362 (19)0.4063 (19)0.060*
O2W0.4410 (2)0.92673 (13)0.61847 (14)0.0623 (5)
H2WA0.385 (3)0.958 (2)0.5722 (19)0.075*
H2WB0.443 (3)0.9689 (18)0.6730 (17)0.075*
N10.16425 (14)0.61714 (10)0.46966 (11)0.0256 (3)
N20.14429 (14)0.90557 (10)0.29043 (11)0.0242 (3)
N3−0.05153 (14)1.05084 (11)0.26799 (11)0.0267 (3)
N4−0.35028 (14)1.12026 (10)0.05522 (11)0.0235 (3)
C10.14831 (17)0.67064 (12)0.38328 (14)0.0254 (4)
H10.08280.65260.33280.031*
C20.22184 (17)0.75090 (12)0.36317 (14)0.0246 (4)
C30.31970 (18)0.77468 (13)0.43639 (15)0.0301 (4)
H30.37380.82830.42510.036*
C40.33772 (19)0.71988 (13)0.52574 (16)0.0336 (4)
H40.40410.73540.57660.040*
C50.25809 (18)0.64246 (13)0.53994 (15)0.0308 (4)
H50.27010.60550.60200.037*
C60.19428 (18)0.80989 (13)0.26599 (14)0.0281 (4)
H6A0.27480.81680.22760.034*
H6B0.13010.77600.21970.034*
C70.02170 (18)0.90049 (13)0.34449 (15)0.0290 (4)
H7A0.03560.86570.41150.035*
H7B−0.04300.86470.30060.035*
C8−0.0291 (2)0.99965 (13)0.36577 (16)0.0309 (4)
H8A−0.11090.99500.40280.037*
H8B0.03441.03500.41120.037*
C90.06858 (18)1.05772 (13)0.21285 (15)0.0307 (4)
H9A0.13261.09530.25550.037*
H9B0.05211.09160.14560.037*
C100.12320 (18)0.95935 (14)0.19196 (14)0.0297 (4)
H10A0.06240.92370.14440.036*
H10B0.20620.96590.15690.036*
C11−0.11128 (18)1.14457 (13)0.28181 (15)0.0312 (4)
H11A−0.04341.19300.29760.037*
H11B−0.16911.14230.34150.037*
C12−0.27629 (17)1.10601 (12)0.14168 (14)0.0247 (4)
H12−0.28431.04680.17720.030*
C13−0.18808 (16)1.17228 (12)0.18317 (14)0.0243 (4)
C14−0.17827 (18)1.25856 (13)0.13158 (15)0.0298 (4)
H14−0.12031.30640.15780.036*
C15−0.25411 (18)1.27477 (13)0.04085 (15)0.0311 (4)
H15−0.24821.33350.00400.037*
C16−0.33791 (17)1.20436 (12)0.00536 (14)0.0261 (4)
H16−0.38921.2156−0.05690.031*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cd10.02129 (11)0.01716 (10)0.02035 (10)0.00052 (6)−0.00332 (7)0.00085 (6)
Cl10.0316 (2)0.0285 (2)0.0221 (2)0.00443 (18)−0.00335 (17)−0.00290 (17)
O1W0.0434 (10)0.0459 (10)0.0592 (11)0.0018 (7)−0.0069 (8)−0.0213 (8)
O2W0.0815 (14)0.0578 (11)0.0473 (10)−0.0181 (10)−0.0018 (9)−0.0145 (8)
N10.0276 (8)0.0227 (8)0.0264 (8)−0.0006 (6)−0.0017 (6)−0.0003 (6)
N20.0242 (7)0.0247 (8)0.0240 (7)−0.0006 (6)0.0033 (6)0.0054 (6)
N30.0272 (8)0.0269 (8)0.0258 (8)0.0029 (6)−0.0011 (6)0.0039 (6)
N40.0234 (7)0.0221 (8)0.0247 (7)−0.0007 (6)−0.0030 (6)−0.0004 (6)
C10.0250 (9)0.0246 (9)0.0266 (9)−0.0002 (7)0.0008 (7)−0.0025 (7)
C20.0247 (9)0.0209 (9)0.0288 (9)0.0033 (7)0.0070 (7)−0.0010 (7)
C30.0267 (9)0.0208 (9)0.0426 (11)−0.0027 (7)0.0014 (8)−0.0005 (8)
C40.0301 (10)0.0288 (10)0.0410 (11)−0.0017 (8)−0.0089 (9)−0.0015 (8)
C50.0326 (10)0.0276 (10)0.0317 (10)0.0009 (8)−0.0044 (8)0.0027 (8)
C60.0310 (10)0.0261 (10)0.0275 (9)−0.0018 (8)0.0059 (8)0.0015 (7)
C70.0278 (9)0.0306 (10)0.0291 (10)−0.0011 (8)0.0055 (8)0.0082 (8)
C80.0288 (10)0.0368 (11)0.0274 (10)0.0037 (8)0.0052 (8)0.0048 (8)
C90.0308 (10)0.0305 (10)0.0308 (10)−0.0018 (8)0.0000 (8)0.0093 (8)
C100.0300 (10)0.0325 (10)0.0269 (9)−0.0008 (8)0.0046 (8)0.0074 (8)
C110.0312 (10)0.0292 (10)0.0324 (10)0.0011 (8)−0.0085 (8)−0.0051 (8)
C120.0267 (9)0.0190 (9)0.0283 (9)0.0002 (7)−0.0011 (7)0.0015 (7)
C130.0215 (9)0.0230 (9)0.0282 (9)0.0011 (7)−0.0016 (7)−0.0033 (7)
C140.0272 (9)0.0223 (9)0.0396 (11)−0.0049 (7)−0.0021 (8)−0.0041 (8)
C150.0370 (11)0.0212 (9)0.0349 (10)−0.0023 (8)0.0002 (8)0.0047 (8)
C160.0293 (9)0.0239 (9)0.0251 (9)0.0016 (7)−0.0010 (7)0.0021 (7)

Geometric parameters (Å, °)

Cd1—N4i2.3728 (14)C4—C51.377 (3)
Cd1—N4ii2.3728 (14)C4—H40.9500
Cd1—N12.4036 (15)C5—H50.9500
Cd1—N1iii2.4036 (15)C6—H6A0.9900
Cd1—Cl12.6074 (4)C6—H6B0.9900
Cd1—Cl1iii2.6074 (4)C7—C81.511 (3)
O1W—H1WA0.874 (16)C7—H7A0.9900
O1W—H1WB0.884 (16)C7—H7B0.9900
O2W—H2WA0.921 (17)C8—H8A0.9900
O2W—H2WB0.912 (17)C8—H8B0.9900
N1—C11.338 (2)C9—C101.515 (3)
N1—C51.342 (2)C9—H9A0.9900
N2—C71.472 (2)C9—H9B0.9900
N2—C61.472 (2)C10—H10A0.9900
N2—C101.474 (2)C10—H10B0.9900
N3—C81.450 (2)C11—C131.511 (2)
N3—C91.458 (2)C11—H11A0.9900
N3—C111.463 (2)C11—H11B0.9900
N4—C121.332 (2)C12—C131.390 (2)
N4—C161.346 (2)C12—H120.9500
N4—Cd1iv2.3728 (14)C13—C141.380 (3)
C1—C21.386 (2)C14—C151.390 (3)
C1—H10.9500C14—H140.9500
C2—C31.389 (3)C15—C161.376 (3)
C2—C61.508 (2)C15—H150.9500
C3—C41.381 (3)C16—H160.9500
C3—H30.9500
N4i—Cd1—N4ii180.0C2—C6—H6B109.2
N4i—Cd1—N194.21 (5)H6A—C6—H6B107.9
N4ii—Cd1—N185.79 (5)N2—C7—C8110.71 (15)
N4i—Cd1—N1iii85.79 (5)N2—C7—H7A109.5
N4ii—Cd1—N1iii94.21 (5)C8—C7—H7A109.5
N1—Cd1—N1iii180.00 (5)N2—C7—H7B109.5
N4i—Cd1—Cl190.60 (4)C8—C7—H7B109.5
N4ii—Cd1—Cl189.40 (4)H7A—C7—H7B108.1
N1—Cd1—Cl187.57 (4)N3—C8—C7109.98 (16)
N1iii—Cd1—Cl192.43 (4)N3—C8—H8A109.7
N4i—Cd1—Cl1iii89.40 (4)C7—C8—H8A109.7
N4ii—Cd1—Cl1iii90.60 (4)N3—C8—H8B109.7
N1—Cd1—Cl1iii92.43 (4)C7—C8—H8B109.7
N1iii—Cd1—Cl1iii87.57 (4)H8A—C8—H8B108.2
Cl1—Cd1—Cl1iii180.0N3—C9—C10110.96 (15)
H1WA—O1W—H1WB100 (2)N3—C9—H9A109.4
H2WA—O2W—H2WB100 (2)C10—C9—H9A109.4
C1—N1—C5117.70 (16)N3—C9—H9B109.4
C1—N1—Cd1116.82 (11)C10—C9—H9B109.4
C5—N1—Cd1124.63 (12)H9A—C9—H9B108.0
C7—N2—C6111.94 (14)N2—C10—C9110.80 (15)
C7—N2—C10109.05 (14)N2—C10—H10A109.5
C6—N2—C10108.82 (14)C9—C10—H10A109.5
C8—N3—C9109.92 (14)N2—C10—H10B109.5
C8—N3—C11113.01 (15)C9—C10—H10B109.5
C9—N3—C11111.90 (15)H10A—C10—H10B108.1
C12—N4—C16117.41 (15)N3—C11—C13109.80 (14)
C12—N4—Cd1iv119.03 (11)N3—C11—H11A109.7
C16—N4—Cd1iv123.53 (11)C13—C11—H11A109.7
N1—C1—C2123.82 (16)N3—C11—H11B109.7
N1—C1—H1118.1C13—C11—H11B109.7
C2—C1—H1118.1H11A—C11—H11B108.2
C1—C2—C3117.32 (16)N4—C12—C13124.16 (16)
C1—C2—C6120.65 (16)N4—C12—H12117.9
C3—C2—C6122.03 (16)C13—C12—H12117.9
C4—C3—C2119.52 (17)C14—C13—C12117.45 (16)
C4—C3—H3120.2C14—C13—C11125.13 (16)
C2—C3—H3120.2C12—C13—C11117.42 (16)
C5—C4—C3118.99 (18)C13—C14—C15119.35 (16)
C5—C4—H4120.5C13—C14—H14120.3
C3—C4—H4120.5C15—C14—H14120.3
N1—C5—C4122.63 (18)C16—C15—C14118.91 (17)
N1—C5—H5118.7C16—C15—H15120.5
C4—C5—H5118.7C14—C15—H15120.5
N2—C6—C2112.20 (14)N4—C16—C15122.71 (16)
N2—C6—H6A109.2N4—C16—H16118.6
C2—C6—H6A109.2C15—C16—H16118.6
N2—C6—H6B109.2
N4i—Cd1—N1—C1138.25 (13)C10—N2—C7—C8−57.93 (19)
N4ii—Cd1—N1—C1−41.75 (13)C9—N3—C8—C7−59.1 (2)
Cl1—Cd1—N1—C1−131.32 (12)C11—N3—C8—C7175.07 (15)
Cl1iii—Cd1—N1—C148.68 (12)N2—C7—C8—N360.0 (2)
N4i—Cd1—N1—C5−52.61 (14)C8—N3—C9—C1058.00 (19)
N4ii—Cd1—N1—C5127.39 (14)C11—N3—C9—C10−175.57 (14)
Cl1—Cd1—N1—C537.82 (14)C7—N2—C10—C956.28 (19)
Cl1iii—Cd1—N1—C5−142.18 (14)C6—N2—C10—C9178.64 (15)
C5—N1—C1—C2−0.8 (3)N3—C9—C10—N2−57.0 (2)
Cd1—N1—C1—C2169.09 (13)C8—N3—C11—C13−153.02 (16)
N1—C1—C2—C31.8 (3)C9—N3—C11—C1382.25 (18)
N1—C1—C2—C6−177.44 (16)C16—N4—C12—C130.1 (3)
C1—C2—C3—C4−1.5 (3)Cd1iv—N4—C12—C13−178.06 (13)
C6—C2—C3—C4177.80 (17)N4—C12—C13—C140.7 (3)
C2—C3—C4—C50.2 (3)N4—C12—C13—C11−179.79 (16)
C1—N1—C5—C4−0.6 (3)N3—C11—C13—C14−129.54 (18)
Cd1—N1—C5—C4−169.62 (14)N3—C11—C13—C1251.0 (2)
C3—C4—C5—N10.9 (3)C12—C13—C14—C15−1.0 (3)
C7—N2—C6—C2−60.88 (19)C11—C13—C14—C15179.54 (18)
C10—N2—C6—C2178.52 (15)C13—C14—C15—C160.5 (3)
C1—C2—C6—N2112.33 (18)C12—N4—C16—C15−0.7 (3)
C3—C2—C6—N2−66.9 (2)Cd1iv—N4—C16—C15177.39 (14)
C6—N2—C7—C8−178.39 (15)C14—C15—C16—N40.4 (3)

Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) −x−1/2, y−1/2, −z+1/2; (iii) −x, −y+1, −z+1; (iv) −x−1/2, y+1/2, −z+1/2.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1W—H1WA···N20.87 (2)2.08 (2)2.950 (2)171 (2)
O1W—H1WB···O2Wv0.88 (2)2.01 (2)2.838 (3)156 (2)
O2W—H2WA···O1W0.92 (2)1.96 (2)2.844 (3)161 (3)
O2W—H2WB···Cl1vi0.91 (2)2.27 (2)3.1607 (17)165 (3)

Symmetry codes: (v) −x+1, −y+2, −z+1; (vi) −x+1/2, y+1/2, −z+3/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LH2863).

References

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