Synthesis and structural studies of a new complex of catena-poly[p-anisidinium [[diiodidobismu­thate(III)]-di-μ-iodido] dihydrate]

Touati, M.E.M.; Elleuch, S.; Boughzala, H.

doi:10.1107/S2056989015019489

research communications

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 71| Part 11| November 2015| Pages 1352-1355

https://doi.org/10.1107/S2056989015019489

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Synthesis and structural studies of a new complex of catena-poly[p-anisidinium [[diiodidobismuthate(III)]-di-μ-iodido] dihydrate]

Mohamed El Mehdi Touati,^a S. Elleuch ^b and Habib Boughzala ^a ^*

^aLaboratoire de Matériaux et Cristallochimie, Faculté des Sciences de Tunis, Université de Tunis El Manar, 2092 Manar II Tunis, Tunisia, and ^bLaboratoire de Physique appliquée, Faculté des Sciences de Sfax, 3018 BP 802, Tunisia
^*Correspondence e-mail: habib.boughzala@ipein.rnu.tn

Edited by A. Van der Lee, Université de Montpellier II, France (Received 20 September 2015; accepted 14 October 2015; online 24 October 2015)

A new organic–inorganic hybrid material, {(C₇H₁₀NO)[BiI₄]·2H₂O}_n, has been synthesized by slow evaporation of an aqueous solution at room temperature. The anionic sublattice of the crystal is built up by [BiI₆] octahedra sharing edges. The resulting zigzag chains extend along the a-axis direction and are arranged in a distorted hexagonal rod packing. The p-anisidinium cations and the water molecules are located in the voids of the anionic sublattice. The cations are linked to each other through N—H⋯O hydrogen bonds with the water molecules, and also through weaker N—H⋯I interactions to the anionic inorganic layers.

Keywords: crystal structure; bismuth iodide; [BiI₆] octahedron; hydrogen bonds; p-anisidinium; hybrid complex.

CCDC reference: 1431306

1. Chemical context

Previous X-ray structural studies showed that halogenidobismuthate(III) complexes may contain an array of variously self-organized halobismuthate anions since different polynuclear species can be formed through oligomerization by halide bridging (Bowmaker et al., 1998 ; Benetollo et al., 1998 ; Alonzo et al., 1999 ).

In general, the coordination sphere of bismuth appears to be dominated by an hexacoordination tendency with polybismuthate species arising from corner-, edge- or face-sharing [BiX₆] distorted octahedra. If the anionic sublattice dimensionality is clearly determined by the counter-cations, the effects of their most evident properties such as charge, size and shape are not predictable. Organic cations resulting from protonated nitrogen functionalities may provide a rich family of salts where the factors cited above could be varied rationally. In addition, since the important contribution to the lattice stabilization in the crystalline state is due to hydrogen-bonding interactions, it should be possible to influence the bismuth coordination geometry by changing the number and orientation of the hydrogen-bond donor sites of the cations. In an effort to increase the size of the [BiX₆] octahedra, iodine was used in the chemical synthesis.

2. Structural commentary

The principal building blocks of the title compound are octahedral iodidobismuthate [BiI₆] units, p-anisidinium cations and two water molecules (Fig. 1). The anionic sublattice of the crystal is built of one-dimensional zigzag chains extending along the a-axis direction and composed of [BiI₆] octahedra sharing edges as shown in Fig. 2. The one-dimensional secondary building unit (SBU) topology observed in the described structure is one of the most common and stable ones (Billing & Lemmerer, 2006 ) in bismuth halide hybrids. The shortest Bi—Bi distance [4.590 (1) Å] observed is in agreement with homologous structures having the same one-dimensional topology. The octahedral bismuth coordination is almost regular, proving the stereochemical inactivity of the Bi³⁺ 6s² electron lone pair. Furthermore, among the six octahedral vertices, two are monocoordinated with short bond lengths (I2 and I3), while the four others (I4, I1 and symmetry-related atoms) are bicoordinated exhibiting long bond lengths (Table 1).

Table 1
Selected bond lengths (Å)

Bi—I2	2.8938 (7)	Bi—I1ⁱⁱ	3.1390 (8)
Bi—I3	2.9850 (7)	Bi—I1	3.1842 (8)
Bi—I4ⁱ	3.0184 (8)	Bi—I4	3.3238 (7)
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x+2, -y+1, -z+1.

Figure 1
Representation of the structural units of (C₇H₁₀NO)[BiI₄]·2H₂O, with 50% probability displacement ellipsoids. [Symmetry codes: (i) 1 − x, 1 − y, 1 − z; (ii) 2 − x, 1 − y, 1 − z.]

Figure 2
View of the anionic framework in the structure of (C₇H₁₀NO)[BiI₄]·2H₂O, showing the zigzag chains running along the a-axis direction.

In Fig. 3, it can be seen that each [BiI₆] octahedron is linked to one p-anisidinium cation and a water molecule OW1 via I3⋯HA—N and I3⋯HW1A—OW1 hydrogen bonds.

Figure 3
The environment of the [BiI₆] octahedron in the structure of (C₇H₁₀NO)[BiI₄]·2H₂O. [Symmetry codes: (i) −x + $[{1\over 2}]$ , y − $[{1\over 2}]$ , −z + $[{1\over 2}]$ ; (ii) −x + $[{3\over 2}]$ , y − $[{1\over 2}]$ , −z + $[{1\over 2}]$ .]

The p-anisidinium cation is adopting a quite planar configuration characterized by a slight r.m.s. deviation of 0.020 (9) Å. Each p-anisidinium cation interacts with one [BiI₆] octahedron via N—HA⋯I3ⁱ ( $[{1\over 2}]$ − x, − $[{1\over 2}]$ + y, $[{1\over 2}]$ − z) , with two water molecules by N—HB⋯OW1ⁱⁱ ( $[{3\over 2}]$ − x, − $[{1\over 2}]$ + y, $[{1\over 2}]$ − z) and N—HC⋯OW2 hydrogen bonds (Table 2), as shown in Fig. 4.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N—HA⋯I3ⁱⁱⁱ	0.89	2.77	3.658 (10)	176
N—HB⋯OW1^iv	0.89	1.97	2.762 (12)	147
N—HC⋯OW2	0.89	1.88	2.704 (14)	154
OW1—HW1A⋯I3	0.85	2.77	3.604 (7)	167
OW2—HW2A⋯I1ⁱ	0.85	3.23	3.817 (10)	129
OW2—HW2A⋯I3	0.85	3.20	3.850 (12)	135
OW2—HW2B⋯OW1^v	0.85	2.32	2.925 (13)	129
Symmetry codes: (i) -x+1, -y+1, -z+1; (iii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (iv) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (v) x-1, y, z.

Figure 4
The environment of the p-anisidinium cation in the structure of (C₇H₁₀NO)[BiI₄]·2H₂O. [Symmetry codes: (i) −x + $[{1\over 2}]$ , y − $[{1\over 2}]$ , −z + $[{1\over 2}]$ ; (ii) $[{3\over 2}]$ − x, − $[{1\over 2}]$ + y, $[{1\over 2}]$ − z.]

3. Supramolecular features

The role of the water molecules is crucial in the crystal cohesion. In fact, OW1 is engaged in three hydrogen bonds to one organic cation, one [BiI₆] octahedra and one water molecule via OW1⋯HBⁱ—Nⁱ, OW1—HW1A⋯I3 and OW1⋯HW2Bⁱⁱ—OW2ⁱⁱ, respectively, as shown in Fig. 5 [symmetry codes: (i) $[{3\over 2}]$ − x, $[{1\over 2}]$ + y, $[{1\over 2}]$ − z; (ii) x + 1, y, z). The second water molecule OW2 is linked to OW1 by OW2—HW2B⋯OW1(−1 + x, y, z) and to the p-anisidinium cation by N—HC⋯OW2 hydrogen bonds as shown in Fig. 6. The role of this water molecule can be seen better in Fig. 7 where molecular stacking along the b axis is observed, leaving an empty interlayer space where OW2 molecules are located, ensuring a strong link between organic and inorganic sheets.

Figure 5
The environment of the OW1 water molecule. [Symmetry codes: (i) $[{3\over 2}]$ − x, $[{1\over 2}]$ + y, $[{1\over 2}]$ − z; (ii) x + 1, y, z.]

Figure 6
The environment of the OW2 water molecule. [Symmetry code: (i) −1 + x, y, z.]

Figure 7
The molecular stacking along the b axis, showing the empty interlayer space where the OW2 water molecules are located.

There are two types of hydrogen bonds, the first one has nitrogen as the donor with iodine as an acceptor to form N—H⋯I bonds. The second type has nitrogen as the donor with oxygen as an acceptor to form N—H⋯O bonds. All these bonds are listed in Table 2. We have to note that HW2A is not involved in hydrogen bonding.

4. Database survey

A systematic search procedure in the Cambridge Structural Database (Version 5.36; Groom & Allen, 2014 ) based on the p-anisidinium cation scheme gives a total of 25 hits. Only two are hybrid compounds: (C₇H₁₀NO)⁺₄[BiCl₆]³⁻·Cl⁻·H₂O (Liu, 2012 ) and (C₇H₁₀NO)⁺_2n[Pb₃I₈]²⁻_n·2nH₂O (Prakash et al., 2009 ).

5. Synthesis and crystallization

The title compound was synthesized by dissolving stoichiometric amounts of bismuth(III) iodide in p-anisidine in a mixture of water and HI. The resulting solution was stirred well and kept at room temperature. Bright-red prismatic crystals were grown by slow evaporation in a couple of weeks. The purity of the synthesized compound was improved by successive recrystallization processes.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3. The hydrogen atoms were located in difference Fourier maps. Those attached to carbon were placed in calculated positions (C—H = 0.90–1.00 Å) while those attached to nitrogen were placed in experimental positions and their coordinates adjusted to give N—H = 0.89 Å. All were included as riding on their parent atoms with isotropic displacement parameters 1.2–1.5 times those of the parent atoms. Hydrogen positions for the water molecules were partly located from a Fourier difference map and partly placed based on geometrical considerations. They are not of sufficient precision to refine the hydrogen-atom positions for the water molecules with angle and distance restraints and they were therefore treated as riding on their parent oxygen atoms.

Table 3
Experimental details

Crystal data
Chemical formula	(C₇H₁₀NO)[BiI₄]·2H₂O
M_r	876.77
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	7.779 (2), 12.747 (2), 18.252 (3)
β (°)	94.97 (1)
V (Å³)	1803.0 (6)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	16.62
Crystal size (mm)	0.6 × 0.2 × 0.1

Data collection
Diffractometer	Enraf–Nonius CAD-4
Absorption correction	ψ scan (North et al., 1968 )
T_min, T_max	0.014, 0.036
No. of measured, independent and observed [I > 2σ(I)] reflections	5050, 3923, 3064
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.080, 1.05
No. of reflections	3923
No. of parameters	147
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.68, −2.01
Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994 ), XCAD4 (Harms & Wocadlo, 1995 ), SHELXS97 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), DIAMOND (Brandenburg, 2008 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1431306

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989015019489/vn2100sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015019489/vn2100Isup2.hkl

checkCIF report

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

catena-Poly[p-anisidinium [[diiodidobismuthate(III)]-di-µ-iodido]] dihydrate] top

Crystal data top

(C₇H₁₀NO)[BiI₄]·2H₂O	F(000) = 1528
M_r = 876.77	D_x = 3.230 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 7.779 (2) Å	Cell parameters from 25 reflections
b = 12.747 (2) Å	θ = 10–15°
c = 18.252 (3) Å	µ = 16.62 mm⁻¹
β = 94.97 (1)°	T = 293 K
V = 1803.0 (6) Å³	Prism, red
Z = 4	0.6 × 0.2 × 0.1 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	3064 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.035
Graphite monochromator	θ_max = 27.0°, θ_min = 2.2°
ω/2θ scans	h = −9→1
Absorption correction: ψ scan (North et al., 1968)	k = −1→16
T_min = 0.014, T_max = 0.036	l = −23→23
5050 measured reflections	2 standard reflections every 120 min
3923 independent reflections	intensity decay: 1%

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.080	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0317P)² + 8.0053P] where P = (F_o² + 2F_c²)/3
3923 reflections	(Δ/σ)_max = 0.001
147 parameters	Δρ_max = 1.68 e Å⁻³
0 restraints	Δρ_min = −2.01 e Å⁻³

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Bi	0.73731 (4)	0.51922 (2)	0.43418 (2)	0.02320 (9)
I1	0.93941 (7)	0.62637 (5)	0.57383 (3)	0.03934 (16)
I2	0.86930 (9)	0.67240 (5)	0.33633 (4)	0.04831 (18)
I3	0.56183 (8)	0.38519 (5)	0.31619 (3)	0.04102 (16)
I4	0.58407 (7)	0.35207 (5)	0.55223 (3)	0.03656 (15)
N	0.2818 (12)	0.0413 (8)	0.2801 (5)	0.059 (2)
HA	0.1983	0.0059	0.2544	0.071*
HB	0.3839	0.0176	0.2689	0.071*
HC	0.2726	0.1092	0.2690	0.071*
C1	0.2662 (13)	0.0267 (9)	0.3590 (6)	0.048 (3)
C2	0.1996 (13)	−0.0648 (9)	0.3862 (6)	0.051 (3)
H2	0.1622	−0.1179	0.3536	0.061*
C3	0.1880 (13)	−0.0783 (8)	0.4581 (6)	0.047 (2)
H3	0.1400	−0.1396	0.4750	0.056*
C4	0.2466 (12)	−0.0020 (7)	0.5077 (6)	0.040 (2)
C5	0.3162 (13)	0.0920 (8)	0.4821 (6)	0.050 (3)
H5	0.3546	0.1446	0.5148	0.060*
C6	0.3261 (13)	0.1043 (8)	0.4071 (6)	0.051 (3)
H6	0.3734	0.1651	0.3892	0.061*
C7	0.1791 (15)	−0.1049 (9)	0.6110 (6)	0.062 (3)
H7A	0.0657	−0.1186	0.5879	0.093*
H7B	0.1738	−0.0991	0.6632	0.093*
H7C	0.2550	−0.1613	0.6006	0.093*
O	0.2425 (9)	−0.0092 (6)	0.5833 (4)	0.0522 (18)
OW1	0.9289 (10)	0.4148 (6)	0.2103 (4)	0.063 (2)
HW1A	0.8384	0.3981	0.2307	0.095*
HW1B	0.9222	0.3883	0.1675	0.095*
OW2	0.1501 (15)	0.2339 (8)	0.2484 (5)	0.110 (4)
HW2A	0.1889	0.2855	0.2745	0.166*
HW2B	0.0502	0.2499	0.2291	0.166*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Bi	0.02239 (16)	0.02297 (16)	0.02394 (14)	−0.00093 (13)	0.00020 (11)	−0.00034 (12)
I1	0.0305 (3)	0.0385 (3)	0.0470 (3)	0.0095 (3)	−0.0082 (2)	−0.0207 (3)
I2	0.0548 (4)	0.0413 (4)	0.0509 (4)	−0.0060 (3)	0.0163 (3)	0.0164 (3)
I3	0.0403 (3)	0.0472 (4)	0.0342 (3)	−0.0063 (3)	−0.0044 (2)	−0.0136 (3)
I4	0.0313 (3)	0.0287 (3)	0.0509 (3)	0.0086 (2)	0.0110 (3)	0.0120 (3)
N	0.056 (6)	0.059 (6)	0.061 (6)	0.007 (5)	0.001 (5)	0.001 (5)
C1	0.034 (5)	0.045 (6)	0.066 (7)	0.008 (5)	0.001 (5)	−0.001 (5)
C2	0.050 (6)	0.040 (6)	0.060 (7)	0.002 (5)	−0.007 (5)	−0.012 (5)
C3	0.046 (6)	0.025 (5)	0.069 (7)	0.000 (4)	0.005 (5)	0.002 (5)
C4	0.027 (5)	0.030 (5)	0.063 (6)	0.005 (4)	−0.001 (4)	0.005 (4)
C5	0.045 (6)	0.028 (5)	0.073 (7)	−0.001 (5)	−0.010 (5)	−0.002 (5)
C6	0.045 (6)	0.034 (6)	0.073 (7)	−0.006 (5)	0.005 (5)	0.010 (5)
C7	0.060 (7)	0.052 (7)	0.071 (8)	−0.008 (6)	−0.010 (6)	0.018 (6)
O	0.051 (4)	0.042 (4)	0.062 (5)	−0.007 (3)	−0.006 (4)	0.000 (4)
OW1	0.063 (5)	0.068 (5)	0.061 (5)	−0.007 (4)	0.019 (4)	0.004 (4)
OW2	0.135 (9)	0.091 (8)	0.098 (8)	0.041 (7)	−0.029 (7)	−0.005 (6)

Geometric parameters (Å, º) top

Bi—I2	2.8938 (7)	C3—C4	1.379 (14)
Bi—I3	2.9850 (7)	C3—H3	0.9300
Bi—I4ⁱ	3.0184 (8)	C4—O	1.386 (13)
Bi—I1ⁱⁱ	3.1390 (8)	C4—C5	1.410 (14)
Bi—I1	3.1842 (8)	C5—C6	1.387 (15)
Bi—I4	3.3238 (7)	C5—H5	0.9300
I1—Biⁱⁱ	3.1390 (8)	C6—H6	0.9300
I4—Biⁱ	3.0184 (8)	C7—O	1.425 (12)
N—C1	1.468 (14)	C7—H7A	0.9600
N—HA	0.8900	C7—H7B	0.9600
N—HB	0.8900	C7—H7C	0.9600
N—HC	0.8900	OW1—HW1A	0.8518
C1—C6	1.376 (15)	OW1—HW1B	0.8479
C1—C2	1.386 (15)	OW2—HW2A	0.8511
C2—C3	1.336 (14)	OW2—HW2B	0.8499
C2—H2	0.9300

I2—Bi—I3	96.05 (2)	C2—C1—N	121.5 (10)
I2—Bi—I4ⁱ	91.41 (2)	C3—C2—C1	121.3 (10)
I3—Bi—I4ⁱ	92.30 (2)	C3—C2—H2	119.4
I2—Bi—I1ⁱⁱ	92.39 (2)	C1—C2—H2	119.4
I3—Bi—I1ⁱⁱ	86.92 (2)	C2—C3—C4	120.5 (10)
I4ⁱ—Bi—I1ⁱⁱ	176.18 (2)	C2—C3—H3	119.8
I2—Bi—I1	91.58 (2)	C4—C3—H3	119.8
I3—Bi—I1	170.46 (2)	C3—C4—O	124.8 (9)
I4ⁱ—Bi—I1	93.21 (2)	C3—C4—C5	119.8 (10)
I1ⁱⁱ—Bi—I1	87.07 (2)	O—C4—C5	115.4 (9)
I2—Bi—I4	177.35 (2)	C6—C5—C4	118.6 (10)
I3—Bi—I4	86.19 (2)	C6—C5—H5	120.7
I4ⁱ—Bi—I4	87.08 (2)	C4—C5—H5	120.7
I1ⁱⁱ—Bi—I4	89.14 (2)	C1—C6—C5	120.3 (10)
I1—Bi—I4	86.33 (2)	C1—C6—H6	119.9
Biⁱⁱ—I1—Bi	92.93 (2)	C5—C6—H6	119.9
Biⁱ—I4—Bi	92.92 (2)	O—C7—H7A	109.5
C1—N—HA	109.5	O—C7—H7B	109.5
C1—N—HB	109.5	H7A—C7—H7B	109.5
HA—N—HB	109.5	O—C7—H7C	109.5
C1—N—HC	109.5	H7A—C7—H7C	109.5
HA—N—HC	109.5	H7B—C7—H7C	109.5
HB—N—HC	109.5	C4—O—C7	116.7 (8)
C6—C1—C2	119.6 (11)	HW1A—OW1—HW1B	108.5
C6—C1—N	118.9 (10)	HW2A—OW2—HW2B	108.4

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N—HA···I3ⁱⁱⁱ	0.89	2.77	3.658 (10)	176
N—HB···OW1^iv	0.89	1.97	2.762 (12)	147
N—HC···OW2	0.89	1.88	2.704 (14)	154
OW1—HW1A···I3	0.85	2.77	3.604 (7)	167
OW2—HW2A···I1ⁱ	0.85	3.23	3.817 (10)	129
OW2—HW2A···I3	0.85	3.20	3.850 (12)	135
OW2—HW2B···OW1^v	0.85	2.32	2.925 (13)	129

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

Acknowledgements

The authors thank the members of the Laboratory of Applied Physics, Faculty of Sciences of Sfax, for the synthesis of the title compound.

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