1,4-Diazo­niabi­cyclo­[2.2.2]octane tetra­chlorido­cadmate(II) monohydrate

The asymmetric unit of the title compound (C₆H₁₄N₂)[CdCl₄]·H₂O contained one 1,4-di­aza­bicyclo­[2.2.2]octane dication, a tetrahedral CdCl₄²⁻ anion and a lattice water mol­ecule. In the crystal, the solvate water mol­ecule inter­acts with the cationic and anionic species via N—H...O and O—H...Cl [O...Cl = 3.289 (7) Å] hydrogen-bond inter­actions, respectively, leading to a layered supramolecular structure extending parallel to (011).

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.010 Å
• R factor = 0.048
• wR factor = 0.134
• Data-to-parameter ratio = 21.0

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT306_ALERT_2_B Isolated Oxygen Atom (H-atoms Missing ?) .......          O Check

Alert level C
PLAT034_ALERT_1_C No Flack Parameter Given. Z > Si, NonCentro ....     Please Do !
PLAT342_ALERT_3_C Low Bond Precision on  C-C Bonds ...............     0.0103 Ang.
PLAT934_ALERT_3_C Number of (Iobs-Icalc)/SigmaW > 10 Outliers ....          1 Check

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite         16 Note
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF     Please Do !
PLAT164_ALERT_4_G Nr. of Refined C-H H-Atoms in Heavy-Atom Struct.         12 Note
PLAT794_ALERT_5_G Tentative Bond Valency for Cd      (II)    .....       2.01 Note
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............         10 Note

   0 ALERT level A = Most likely a serious problem - resolve or explain
   1 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   5 ALERT level G = General information/check it is not something unexpected

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   2 ALERT type 5 Informative message, check

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S1. Comment

In recent years, a significant number of organic–inorganic hybrid materials based on metal halide units have been prepared and studied (Lemmerer & Billing, 2012). It has been shown that their structures can vary considerably, ranging from systems based on isolated polyhydra to ones containing extended chains and up to two- or three-dimensional networks (Ben Rhaiem et al., 2013; Samet et al., 2010; Billing & Lemmerer, 2009). Generally, the organic cations contain ammonium groups linked to the anionic framework by hydrogen bonds via halogenous tetrahedral vertices (Sun & Qu, 2005) and (Zhang & Zhu, 2012). In pseudopolymorphic cases, the water molecules can be able to coordinate the charged components strengthening the crystal cohesion as it was observed in (dabcoH₂)CuCl₄ and (dabcoH₂)CuCl₄·H₂O (Wei & Willett, 2002).

The new chloridocadmate(II) compound, (C₆H₁₄N₂) [CdCl₄]·H₂O (I), is self-assembled into alternating organic and inorganic layered structure. the organic part is made up of 1,4-diazabicyclo[2.2.2]octane cations and water molecules. The inorganic component contains isolated [CdCl₄]^2- units. The layers are stacked along the c axis, as illustrated in Fig. 1.

The asymmetric unit of (I) comprises one 1,4-diazabicyclo[2.2.2]octane cation, one [CdCl₄]^2- anion and a lattice occluded water molecule (Fig. 2).

The [CdCl₄]^2- unit possesses a configuration of distorted tetrahedron, so that the central cadmium (II) ion is surrounded by four chlorine atoms. The Cd–Cl bond lengths vary from 2.430 (2) Å to 2.4864 (17) Å and the Cl–Cd–Cl angles fall in the range 101.80 (6)°–116.95 (6)°.

The protonated N2 atom of the organic cation interacts via a simple hydrogen bond with oxygen atom of the water molecule (Fig. 3 and Tab. 1).

Related literature

For background to this class of compounds, see: Wei & Willett (2002); Billing & Lemmerer (2009); Samet et al. (2010) Lemmerer & Billing (2012); Ben Rhaiem et al. (2013). For related structures, see: Sun & Qu (2005); Zhang & Zhu (2012).

S2. Experimental

The title compound (C₆H₁₄N₂) [CdCl₄]·H₂O, (I), was obtained by the reaction of cadmium iodide CdI₂ (0.19 g, 0.5 mmol) with DABCO (1,4-diazabicyclo[2.2.2]octane) (0.112 g, 1 mmol) in aqueous hydrochloric acid solution with pH ranging between 3 and 4. The mixture was stirred for several minutes. Colorless crystals suitable for X-ray diffraction analysis were obtained by slow evaporation at room temperature over 2 weeks.

S3. Refinement

Hydrogen water molecules are omited. The C—H and N—H hydrogen atoms positions are generated geometrically by HFIX SHELXL command.

Computing details

Data collection: CAD-4 EXPRESS (Duisenberg, 1992); cell refinement: CAD-4 EXPRESS (Duisenberg, 1992); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. Packing diagram of (I), projected along the a axis.
	Fig. 2. The asymmetric unit of (I), showing the atom numbering scheme. Displacement ellipsoids are drawn at 50% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 3. The arrangement of ions of (I), projected along the b axis. [Symmetry code: (i) -x, y+1/2, -z + 1/2.]

1,4-Diazoniabicyclo[2.2.2]octane tetrachloridocadmate(II) monohydrate

Crystal data

(C6H14N2)[CdCl4]·H2O	F(000) = 752
Mr = 386.40	Dx = 1.959 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2837 reflections
a = 8.528 (5) Å	θ = 2.4–27°
b = 11.653 (2) Å	µ = 2.47 mm^−1
c = 13.114 (6) Å	T = 298 K
V = 1303.2 (10) Å^3	Prism, colorless
Z = 4	0.54 × 0.43 × 0.29 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	2632 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.075
Graphite monochromator	θmax = 27.0°, θmin = 2.3°
non–profiled ω/2θ scans	h = −10→6
Absorption correction: ψ scan (North et al. (1968)	k = −14→1
Tmin = 0.283, Tmax = 0.536	l = −16→16
5639 measured reflections	2 standard reflections every 120 min
2837 independent reflections	intensity decay: 1%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.134	H-atom parameters not refined
S = 1.19	w = 1/[σ^2(Fo^2) + (0.0587P)^2 + 1.6133P] where P = (Fo^2 + 2Fc^2)/3
2837 reflections	(Δ/σ)max = 0.001
135 parameters	Δρmax = 1.58 e Å^−3
10 restraints	Δρmin = −1.44 e Å^−3

Special details

Experimental. Number of psi-scan sets used was 5 Theta correction was applied. Averaged transmission function was used. No Fourier smoothing was applied.

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 (Ų)

	x	y	z	Uiso*/Ueq
Cd	0.74636 (5)	0.52500 (4)	0.50315 (3)	0.04606 (17)
Cl1	0.52000 (18)	0.40196 (13)	0.46103 (13)	0.0465 (3)
Cl2	0.7583 (2)	0.53068 (14)	0.69230 (11)	0.0544 (4)
Cl3	0.9940 (2)	0.43346 (15)	0.46078 (15)	0.0557 (4)
Cl4	0.6884 (2)	0.71103 (15)	0.41831 (12)	0.0542 (4)
C1	0.4091 (7)	0.6836 (5)	0.2060 (5)	0.0457 (13)
H1A	0.498 (5)	0.6620 (12)	0.153 (3)	0.055*
H1B	0.4419 (18)	0.761 (4)	0.2435 (19)	0.055*
C2	0.2540 (8)	0.6998 (6)	0.1512 (5)	0.0514 (13)
H2A	0.2282 (17)	0.776 (5)	0.1496 (5)	0.062*
H2B	0.2617 (9)	0.6741 (16)	0.086 (4)	0.062*
C3	0.2824 (8)	0.6248 (7)	0.3636 (6)	0.0583 (18)
H3A	0.3266 (11)	0.6796 (11)	0.4005 (8)	0.070*
H3B	0.2613 (9)	0.5660 (12)	0.4042 (9)	0.070*
C4	0.1319 (9)	0.6690 (6)	0.3149 (6)	0.065 (2)
H4A	0.0481 (16)	0.6394 (8)	0.3470 (8)	0.078*
H4B	0.1274 (9)	0.7458 (14)	0.3198 (7)	0.078*
C5	0.3284 (9)	0.4857 (5)	0.2294 (6)	0.0519 (16)
H5A	0.3330 (9)	0.4244 (11)	0.2713 (9)	0.062*
H5B	0.3874 (13)	0.4708 (6)	0.1738 (11)	0.062*
C6	0.1623 (9)	0.5077 (6)	0.1985 (7)	0.0586 (18)
H6A	0.0970 (14)	0.4692 (9)	0.2392 (9)	0.070*
H6B	0.1468 (9)	0.4843 (7)	0.1344 (12)	0.070*
N1	0.3888 (6)	0.5887 (5)	0.2823 (4)	0.0431 (11)
H1	0.477 (2)	0.5730 (6)	0.3082 (7)	0.052*
N2	0.1318 (6)	0.6341 (5)	0.2067 (5)	0.0554 (15)
H2	0.043 (2)	0.6488 (6)	0.1811 (8)	0.067*
O	0.1563 (8)	0.2409 (6)	0.3238 (6)	0.0861 (19)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cd	0.0463 (3)	0.0409 (2)	0.0510 (3)	0.00213 (18)	−0.0028 (2)	0.00245 (17)
Cl1	0.0486 (8)	0.0402 (7)	0.0508 (8)	−0.0018 (6)	0.0024 (6)	−0.0039 (6)
Cl2	0.0613 (8)	0.0530 (8)	0.0490 (7)	0.0058 (9)	−0.0041 (8)	−0.0042 (6)
Cl3	0.0519 (8)	0.0515 (8)	0.0635 (9)	0.0105 (7)	0.0063 (7)	0.0105 (8)
Cl4	0.0684 (9)	0.0423 (7)	0.0520 (8)	0.0014 (7)	−0.0163 (7)	0.0047 (7)
C1	0.042 (3)	0.034 (3)	0.061 (3)	−0.005 (2)	0.004 (3)	0.007 (3)
C2	0.049 (3)	0.048 (3)	0.057 (3)	−0.006 (3)	−0.001 (3)	0.020 (3)
C3	0.063 (5)	0.057 (4)	0.056 (3)	−0.006 (3)	0.006 (3)	−0.005 (3)
C4	0.062 (4)	0.046 (4)	0.087 (5)	0.012 (3)	0.032 (4)	0.012 (4)
C5	0.055 (4)	0.026 (2)	0.075 (4)	0.001 (3)	−0.008 (3)	0.002 (3)
C6	0.061 (4)	0.041 (3)	0.075 (5)	−0.008 (3)	−0.016 (4)	0.006 (3)
N1	0.042 (2)	0.040 (2)	0.047 (3)	0.002 (2)	−0.005 (2)	0.004 (2)
N2	0.038 (3)	0.044 (3)	0.084 (4)	0.004 (2)	−0.004 (3)	0.027 (3)
O	0.085 (4)	0.070 (4)	0.103 (5)	−0.014 (3)	0.008 (4)	−0.009 (4)

Geometric parameters (Å, º)

Cd—Cl3	2.430 (2)	C3—H3B	0.8860
Cd—Cl1	2.4673 (18)	C4—N2	1.476 (11)
Cd—Cl2	2.4835 (19)	C4—H4A	0.8977
Cd—Cl4	2.4864 (17)	C4—H4B	0.8977
C1—N1	1.502 (8)	C5—N1	1.479 (9)
C1—C2	1.517 (9)	C5—C6	1.496 (10)
C1—H1A	1.0614	C5—H5A	0.9026
C1—H1B	1.0614	C5—H5B	0.9026
C2—N2	1.485 (8)	C6—N2	1.499 (9)
C2—H2A	0.9127	C6—H6A	0.8931
C2—H2B	0.9127	C6—H6B	0.8931
C3—N1	1.461 (9)	N1—H1	0.8477
C3—C4	1.524 (10)	N2—H2	0.8420
C3—H3A	0.8860
Cl3—Cd—Cl1	111.93 (7)	N2—C4—H4B	110.1
Cl3—Cd—Cl2	101.80 (6)	C3—C4—H4B	110.1
Cl1—Cd—Cl2	105.73 (6)	H4A—C4—H4B	108.4
Cl3—Cd—Cl4	116.95 (6)	N1—C5—C6	108.5 (5)
Cl1—Cd—Cl4	104.53 (6)	N1—C5—H5A	110.0
Cl2—Cd—Cl4	115.58 (6)	C6—C5—H5A	110.0
N1—C1—C2	107.9 (5)	N1—C5—H5B	110.0
N1—C1—H1A	110.1	C6—C5—H5B	110.0
C2—C1—H1A	110.1	H5A—C5—H5B	108.4
N1—C1—H1B	110.1	C5—C6—N2	108.3 (5)
C2—C1—H1B	110.1	C5—C6—H6A	110.0
H1A—C1—H1B	108.4	N2—C6—H6A	110.0
N2—C2—C1	108.4 (5)	C5—C6—H6B	110.0
N2—C2—H2A	110.0	N2—C6—H6B	110.0
C1—C2—H2A	110.0	H6A—C6—H6B	108.4
N2—C2—H2B	110.0	C3—N1—C5	111.1 (6)
C1—C2—H2B	110.0	C3—N1—C1	110.2 (5)
H2A—C2—H2B	108.4	C5—N1—C1	109.0 (5)
N1—C3—C4	108.4 (6)	C3—N1—H1	108.8
N1—C3—H3A	110.0	C5—N1—H1	108.8
C4—C3—H3A	110.0	C1—N1—H1	108.8
N1—C3—H3B	110.0	C4—N2—C2	109.2 (6)
C4—C3—H3B	110.0	C4—N2—C6	109.9 (6)
H3A—C3—H3B	108.4	C2—N2—C6	110.5 (6)
N2—C4—C3	108.0 (5)	C4—N2—H2	109.1
N2—C4—H4A	110.1	C2—N2—H2	109.1
C3—C4—H4A	110.1	C6—N2—H2	109.1

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O^i	0.84	2.01	2.783 (1)	151

Symmetry code: (i) −x, y+1/2, −z+1/2.