Poly[[bis­[μ-1,4-bis­(3-pyridylmeth­yl)piperazine-κ2N:N′]dichlorido­cadmium(II)] tetra­hydrate]

Blake, K.M.; LaDuca, R.L.

doi:10.1107/S1600536809027767

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page m947

doi:10.1107/S1600536809027767

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Poly[[bis[μ-1,4-bis(3-pyridylmethyl)piperazine-κ²N:N′]dichloridocadmium(II)] tetrahydrate]

Karyn M. Blake ^a and Robert L. LaDuca ^a ^*

^aLyman Briggs College, Department of Chemistry, Michigan State University, East Lansing, MI 48825, USA
^*Correspondence e-mail: laduca@msu.edu

(Received 10 July 2009; accepted 14 July 2009; online 18 July 2009)

In the title compound, {[CdCl₂(C₁₆H₂₀N₄)₂]·4H₂O}_n, octahedrally coordinated Cd^II 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 ( $[\overline{1}]$ 01) 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 ). For the preparation of N,N′-bis(3-pyridylmethyl)piperazine, see: Pocic et al. (2005 ).

Experimental

Crystal data

[CdCl₂(C₁₆H₂₀N₄)₂]·4H₂O
M_r = 792.08
Monoclinic, P 2₁ /n
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 ) 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[F² > 2σ(F²)] = 0.021
wR(F²) = 0.055
S = 1.07
3391 reflections
226 parameters
6 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1WA⋯N2	0.874 (16)	2.084 (17)	2.950 (2)	171 (2)
O1W—H1WB⋯O2Wⁱ	0.884 (16)	2.007 (18)	2.838 (3)	156 (2)
O2W—H2WA⋯O1W	0.921 (17)	1.958 (19)	2.844 (3)	161 (3)
O2W—H2WB⋯Cl1ⁱⁱ	0.912 (17)	2.272 (18)	3.1607 (17)	165 (3)
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

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

Supporting information

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

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

checkCIF report

Comment top

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 Cd^II 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 Cd^II 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.

Related literature top

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

Experimental top

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.

Computing details top

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

Figures top

	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, -y+3/2, z+1/2 (ii) -x-1/2, y-1/2, -z+1/2 (iii) -x, -y+1, -z+1.
	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.

Poly[[bis[µ-1,4-bis(3-pyridylmethyl)piperazine- κ²N:N']dichloridocadmium(II)] tetrahydrate] top

Crystal data top

[CdCl₂(C₁₆H₂₀N₄)₂]·4H₂O	F(000) = 820
M_r = 792.08	D_x = 1.424 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 16643 reflections
a = 10.3481 (2) Å	θ = 2.2–25.4°
b = 13.9791 (2) Å	µ = 0.78 mm⁻¹
c = 12.7789 (2) Å	T = 173 K
β = 92.473 (1)°	Fragment, colourless
V = 1846.84 (5) Å³	0.38 × 0.35 × 0.19 mm
Z = 2

Data collection top

Bruker APEXII diffractometer	3391 independent reflections
Radiation source: fine-focus sealed tube	3060 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
ω and ϕ scans	θ_max = 25.4°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −12→12
T_min = 0.753, T_max = 0.868	k = −15→16
16443 measured reflections	l = −15→15

Refinement top

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)] = 0.021	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.055	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ²(F_o²) + (0.0261P)² + 0.7641P] where P = (F_o² + 2F_c²)/3
3391 reflections	(Δ/σ)_max = 0.001
226 parameters	Δρ_max = 0.42 e Å⁻³
6 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

[CdCl₂(C₁₆H₂₀N₄)₂]·4H₂O	V = 1846.84 (5) Å³
M_r = 792.08	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 10.3481 (2) Å	µ = 0.78 mm⁻¹
b = 13.9791 (2) Å	T = 173 K
c = 12.7789 (2) Å	0.38 × 0.35 × 0.19 mm
β = 92.473 (1)°

Data collection top

Bruker APEXII diffractometer	3391 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3060 reflections with I > 2σ(I)
T_min = 0.753, T_max = 0.868	R_int = 0.027
16443 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	6 restraints
wR(F²) = 0.055	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 0.42 e Å⁻³
3391 reflections	Δρ_min = −0.23 e Å⁻³
226 parameters

Special details top

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) top

	x	y	z	U_iso*/U_eq
Cd1	0.0000	0.5000	0.5000	0.01972 (7)
Cl1	−0.00576 (4)	0.56521 (3)	0.69090 (3)	0.02753 (11)
O1W	0.31111 (17)	1.01315 (12)	0.44201 (15)	0.0498 (4)
H1WA	0.267 (2)	0.9840 (17)	0.3915 (18)	0.060*
H1WB	0.375 (2)	1.0362 (19)	0.4063 (19)	0.060*
O2W	0.4410 (2)	0.92673 (13)	0.61847 (14)	0.0623 (5)
H2WA	0.385 (3)	0.958 (2)	0.5722 (19)	0.075*
H2WB	0.443 (3)	0.9689 (18)	0.6730 (17)	0.075*
N1	0.16425 (14)	0.61714 (10)	0.46966 (11)	0.0256 (3)
N2	0.14429 (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)
C1	0.14831 (17)	0.67064 (12)	0.38328 (14)	0.0254 (4)
H1	0.0828	0.6526	0.3328	0.031*
C2	0.22184 (17)	0.75090 (12)	0.36317 (14)	0.0246 (4)
C3	0.31970 (18)	0.77468 (13)	0.43639 (15)	0.0301 (4)
H3	0.3738	0.8283	0.4251	0.036*
C4	0.33772 (19)	0.71988 (13)	0.52574 (16)	0.0336 (4)
H4	0.4041	0.7354	0.5766	0.040*
C5	0.25809 (18)	0.64246 (13)	0.53994 (15)	0.0308 (4)
H5	0.2701	0.6055	0.6020	0.037*
C6	0.19428 (18)	0.80989 (13)	0.26599 (14)	0.0281 (4)
H6A	0.2748	0.8168	0.2276	0.034*
H6B	0.1301	0.7760	0.2197	0.034*
C7	0.02170 (18)	0.90049 (13)	0.34449 (15)	0.0290 (4)
H7A	0.0356	0.8657	0.4115	0.035*
H7B	−0.0430	0.8647	0.3006	0.035*
C8	−0.0291 (2)	0.99965 (13)	0.36577 (16)	0.0309 (4)
H8A	−0.1109	0.9950	0.4028	0.037*
H8B	0.0344	1.0350	0.4112	0.037*
C9	0.06858 (18)	1.05772 (13)	0.21285 (15)	0.0307 (4)
H9A	0.1326	1.0953	0.2555	0.037*
H9B	0.0521	1.0916	0.1456	0.037*
C10	0.12320 (18)	0.95935 (14)	0.19196 (14)	0.0297 (4)
H10A	0.0624	0.9237	0.1444	0.036*
H10B	0.2062	0.9659	0.1569	0.036*
C11	−0.11128 (18)	1.14457 (13)	0.28181 (15)	0.0312 (4)
H11A	−0.0434	1.1930	0.2976	0.037*
H11B	−0.1691	1.1423	0.3415	0.037*
C12	−0.27629 (17)	1.10601 (12)	0.14168 (14)	0.0247 (4)
H12	−0.2843	1.0468	0.1772	0.030*
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	−0.1203	1.3064	0.1578	0.036*
C15	−0.25411 (18)	1.27477 (13)	0.04085 (15)	0.0311 (4)
H15	−0.2482	1.3335	0.0040	0.037*
C16	−0.33791 (17)	1.20436 (12)	0.00536 (14)	0.0261 (4)
H16	−0.3892	1.2156	−0.0569	0.031*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.02129 (11)	0.01716 (10)	0.02035 (10)	0.00052 (6)	−0.00332 (7)	0.00085 (6)
Cl1	0.0316 (2)	0.0285 (2)	0.0221 (2)	0.00443 (18)	−0.00335 (17)	−0.00290 (17)
O1W	0.0434 (10)	0.0459 (10)	0.0592 (11)	0.0018 (7)	−0.0069 (8)	−0.0213 (8)
O2W	0.0815 (14)	0.0578 (11)	0.0473 (10)	−0.0181 (10)	−0.0018 (9)	−0.0145 (8)
N1	0.0276 (8)	0.0227 (8)	0.0264 (8)	−0.0006 (6)	−0.0017 (6)	−0.0003 (6)
N2	0.0242 (7)	0.0247 (8)	0.0240 (7)	−0.0006 (6)	0.0033 (6)	0.0054 (6)
N3	0.0272 (8)	0.0269 (8)	0.0258 (8)	0.0029 (6)	−0.0011 (6)	0.0039 (6)
N4	0.0234 (7)	0.0221 (8)	0.0247 (7)	−0.0007 (6)	−0.0030 (6)	−0.0004 (6)
C1	0.0250 (9)	0.0246 (9)	0.0266 (9)	−0.0002 (7)	0.0008 (7)	−0.0025 (7)
C2	0.0247 (9)	0.0209 (9)	0.0288 (9)	0.0033 (7)	0.0070 (7)	−0.0010 (7)
C3	0.0267 (9)	0.0208 (9)	0.0426 (11)	−0.0027 (7)	0.0014 (8)	−0.0005 (8)
C4	0.0301 (10)	0.0288 (10)	0.0410 (11)	−0.0017 (8)	−0.0089 (9)	−0.0015 (8)
C5	0.0326 (10)	0.0276 (10)	0.0317 (10)	0.0009 (8)	−0.0044 (8)	0.0027 (8)
C6	0.0310 (10)	0.0261 (10)	0.0275 (9)	−0.0018 (8)	0.0059 (8)	0.0015 (7)
C7	0.0278 (9)	0.0306 (10)	0.0291 (10)	−0.0011 (8)	0.0055 (8)	0.0082 (8)
C8	0.0288 (10)	0.0368 (11)	0.0274 (10)	0.0037 (8)	0.0052 (8)	0.0048 (8)
C9	0.0308 (10)	0.0305 (10)	0.0308 (10)	−0.0018 (8)	0.0000 (8)	0.0093 (8)
C10	0.0300 (10)	0.0325 (10)	0.0269 (9)	−0.0008 (8)	0.0046 (8)	0.0074 (8)
C11	0.0312 (10)	0.0292 (10)	0.0324 (10)	0.0011 (8)	−0.0085 (8)	−0.0051 (8)
C12	0.0267 (9)	0.0190 (9)	0.0283 (9)	0.0002 (7)	−0.0011 (7)	0.0015 (7)
C13	0.0215 (9)	0.0230 (9)	0.0282 (9)	0.0011 (7)	−0.0016 (7)	−0.0033 (7)
C14	0.0272 (9)	0.0223 (9)	0.0396 (11)	−0.0049 (7)	−0.0021 (8)	−0.0041 (8)
C15	0.0370 (11)	0.0212 (9)	0.0349 (10)	−0.0023 (8)	0.0002 (8)	0.0047 (8)
C16	0.0293 (9)	0.0239 (9)	0.0251 (9)	0.0016 (7)	−0.0010 (7)	0.0021 (7)

Geometric parameters (Å, º) top

Cd1—N4ⁱ	2.3728 (14)	C4—C5	1.377 (3)
Cd1—N4ⁱⁱ	2.3728 (14)	C4—H4	0.9500
Cd1—N1	2.4036 (15)	C5—H5	0.9500
Cd1—N1ⁱⁱⁱ	2.4036 (15)	C6—H6A	0.9900
Cd1—Cl1	2.6074 (4)	C6—H6B	0.9900
Cd1—Cl1ⁱⁱⁱ	2.6074 (4)	C7—C8	1.511 (3)
O1W—H1WA	0.874 (16)	C7—H7A	0.9900
O1W—H1WB	0.884 (16)	C7—H7B	0.9900
O2W—H2WA	0.921 (17)	C8—H8A	0.9900
O2W—H2WB	0.912 (17)	C8—H8B	0.9900
N1—C1	1.338 (2)	C9—C10	1.515 (3)
N1—C5	1.342 (2)	C9—H9A	0.9900
N2—C7	1.472 (2)	C9—H9B	0.9900
N2—C6	1.472 (2)	C10—H10A	0.9900
N2—C10	1.474 (2)	C10—H10B	0.9900
N3—C8	1.450 (2)	C11—C13	1.511 (2)
N3—C9	1.458 (2)	C11—H11A	0.9900
N3—C11	1.463 (2)	C11—H11B	0.9900
N4—C12	1.332 (2)	C12—C13	1.390 (2)
N4—C16	1.346 (2)	C12—H12	0.9500
N4—Cd1^iv	2.3728 (14)	C13—C14	1.380 (3)
C1—C2	1.386 (2)	C14—C15	1.390 (3)
C1—H1	0.9500	C14—H14	0.9500
C2—C3	1.389 (3)	C15—C16	1.376 (3)
C2—C6	1.508 (2)	C15—H15	0.9500
C3—C4	1.381 (3)	C16—H16	0.9500
C3—H3	0.9500

N4ⁱ—Cd1—N4ⁱⁱ	180.0	C2—C6—H6B	109.2
N4ⁱ—Cd1—N1	94.21 (5)	H6A—C6—H6B	107.9
N4ⁱⁱ—Cd1—N1	85.79 (5)	N2—C7—C8	110.71 (15)
N4ⁱ—Cd1—N1ⁱⁱⁱ	85.79 (5)	N2—C7—H7A	109.5
N4ⁱⁱ—Cd1—N1ⁱⁱⁱ	94.21 (5)	C8—C7—H7A	109.5
N1—Cd1—N1ⁱⁱⁱ	180.00 (5)	N2—C7—H7B	109.5
N4ⁱ—Cd1—Cl1	90.60 (4)	C8—C7—H7B	109.5
N4ⁱⁱ—Cd1—Cl1	89.40 (4)	H7A—C7—H7B	108.1
N1—Cd1—Cl1	87.57 (4)	N3—C8—C7	109.98 (16)
N1ⁱⁱⁱ—Cd1—Cl1	92.43 (4)	N3—C8—H8A	109.7
N4ⁱ—Cd1—Cl1ⁱⁱⁱ	89.40 (4)	C7—C8—H8A	109.7
N4ⁱⁱ—Cd1—Cl1ⁱⁱⁱ	90.60 (4)	N3—C8—H8B	109.7
N1—Cd1—Cl1ⁱⁱⁱ	92.43 (4)	C7—C8—H8B	109.7
N1ⁱⁱⁱ—Cd1—Cl1ⁱⁱⁱ	87.57 (4)	H8A—C8—H8B	108.2
Cl1—Cd1—Cl1ⁱⁱⁱ	180.0	N3—C9—C10	110.96 (15)
H1WA—O1W—H1WB	100 (2)	N3—C9—H9A	109.4
H2WA—O2W—H2WB	100 (2)	C10—C9—H9A	109.4
C1—N1—C5	117.70 (16)	N3—C9—H9B	109.4
C1—N1—Cd1	116.82 (11)	C10—C9—H9B	109.4
C5—N1—Cd1	124.63 (12)	H9A—C9—H9B	108.0
C7—N2—C6	111.94 (14)	N2—C10—C9	110.80 (15)
C7—N2—C10	109.05 (14)	N2—C10—H10A	109.5
C6—N2—C10	108.82 (14)	C9—C10—H10A	109.5
C8—N3—C9	109.92 (14)	N2—C10—H10B	109.5
C8—N3—C11	113.01 (15)	C9—C10—H10B	109.5
C9—N3—C11	111.90 (15)	H10A—C10—H10B	108.1
C12—N4—C16	117.41 (15)	N3—C11—C13	109.80 (14)
C12—N4—Cd1^iv	119.03 (11)	N3—C11—H11A	109.7
C16—N4—Cd1^iv	123.53 (11)	C13—C11—H11A	109.7
N1—C1—C2	123.82 (16)	N3—C11—H11B	109.7
N1—C1—H1	118.1	C13—C11—H11B	109.7
C2—C1—H1	118.1	H11A—C11—H11B	108.2
C1—C2—C3	117.32 (16)	N4—C12—C13	124.16 (16)
C1—C2—C6	120.65 (16)	N4—C12—H12	117.9
C3—C2—C6	122.03 (16)	C13—C12—H12	117.9
C4—C3—C2	119.52 (17)	C14—C13—C12	117.45 (16)
C4—C3—H3	120.2	C14—C13—C11	125.13 (16)
C2—C3—H3	120.2	C12—C13—C11	117.42 (16)
C5—C4—C3	118.99 (18)	C13—C14—C15	119.35 (16)
C5—C4—H4	120.5	C13—C14—H14	120.3
C3—C4—H4	120.5	C15—C14—H14	120.3
N1—C5—C4	122.63 (18)	C16—C15—C14	118.91 (17)
N1—C5—H5	118.7	C16—C15—H15	120.5
C4—C5—H5	118.7	C14—C15—H15	120.5
N2—C6—C2	112.20 (14)	N4—C16—C15	122.71 (16)
N2—C6—H6A	109.2	N4—C16—H16	118.6
C2—C6—H6A	109.2	C15—C16—H16	118.6
N2—C6—H6B	109.2

N4ⁱ—Cd1—N1—C1	138.25 (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—C7	175.07 (15)
Cl1ⁱⁱⁱ—Cd1—N1—C1	48.68 (12)	N2—C7—C8—N3	60.0 (2)
N4ⁱ—Cd1—N1—C5	−52.61 (14)	C8—N3—C9—C10	58.00 (19)
N4ⁱⁱ—Cd1—N1—C5	127.39 (14)	C11—N3—C9—C10	−175.57 (14)
Cl1—Cd1—N1—C5	37.82 (14)	C7—N2—C10—C9	56.28 (19)
Cl1ⁱⁱⁱ—Cd1—N1—C5	−142.18 (14)	C6—N2—C10—C9	178.64 (15)
C5—N1—C1—C2	−0.8 (3)	N3—C9—C10—N2	−57.0 (2)
Cd1—N1—C1—C2	169.09 (13)	C8—N3—C11—C13	−153.02 (16)
N1—C1—C2—C3	1.8 (3)	C9—N3—C11—C13	82.25 (18)
N1—C1—C2—C6	−177.44 (16)	C16—N4—C12—C13	0.1 (3)
C1—C2—C3—C4	−1.5 (3)	Cd1^iv—N4—C12—C13	−178.06 (13)
C6—C2—C3—C4	177.80 (17)	N4—C12—C13—C14	0.7 (3)
C2—C3—C4—C5	0.2 (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—C12	51.0 (2)
C3—C4—C5—N1	0.9 (3)	C12—C13—C14—C15	−1.0 (3)
C7—N2—C6—C2	−60.88 (19)	C11—C13—C14—C15	179.54 (18)
C10—N2—C6—C2	178.52 (15)	C13—C14—C15—C16	0.5 (3)
C1—C2—C6—N2	112.33 (18)	C12—N4—C16—C15	−0.7 (3)
C3—C2—C6—N2	−66.9 (2)	Cd1^iv—N4—C16—C15	177.39 (14)
C6—N2—C7—C8	−178.39 (15)	C14—C15—C16—N4	0.4 (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, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···N2	0.87 (2)	2.08 (2)	2.950 (2)	171 (2)
O1W—H1WB···O2W^v	0.88 (2)	2.01 (2)	2.838 (3)	156 (2)
O2W—H2WA···O1W	0.92 (2)	1.96 (2)	2.844 (3)	161 (3)
O2W—H2WB···Cl1^vi	0.91 (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.

Experimental details

Crystal data
Chemical formula	[CdCl₂(C₁₆H₂₀N₄)₂]·4H₂O
M_r	792.08
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	173
a, b, c (Å)	10.3481 (2), 13.9791 (2), 12.7789 (2)
β (°)	92.473 (1)
V (Å³)	1846.84 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.78
Crystal size (mm)	0.38 × 0.35 × 0.19

Data collection
Diffractometer	Bruker APEXII diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.753, 0.868
No. of measured, independent and observed [I > 2σ(I)] reflections	16443, 3391, 3060
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.055, 1.07
No. of reflections	3391
No. of parameters	226
No. of restraints	6
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.23

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), CrystalMaker (Palmer, 2007).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···N2	0.874 (16)	2.084 (17)	2.950 (2)	171 (2)
O1W—H1WB···O2Wⁱ	0.884 (16)	2.007 (18)	2.838 (3)	156 (2)
O2W—H2WA···O1W	0.921 (17)	1.958 (19)	2.844 (3)	161 (3)
O2W—H2WB···Cl1ⁱⁱ	0.912 (17)	2.272 (18)	3.1607 (17)	165 (3)

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

Acknowledgements

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

References

Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
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Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar

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