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Acta Cryst. (2013). E69, m65-m66    [ doi:10.1107/S1600536812050817 ]

Bis[(1RS,2RS)-4,4'-(1-azaniumyl-2-hydroxyethane-1,2-diyl)dipyridinium] tris[tetrachloridopalladate(II)]

J. J. Campos-Gaxiola, A. Baez-Castro, A. Cruz-Enriquez, H. Hopfl and M. Parra-Hake

Abstract top

The asymmetric unit of the title compound, (C12H16N3O)2[PdCl4]3, consists of a 4,4'-(1-azaniumyl-2-hydroxyethane-1,2-diyl)dipyridinium dication and one and a half tetrachloridopalladate(II) anions; the latter has inversion symmetry. In the cation, the pyridinium rings attached to the central 1-azaniumyl-2-hydroxyethane fragment show an anti conformation, as indicated by the central C-C-C-C torsion angle of -178.1 (4)°, and they are inclined to one another by 25.7 (2)°. In the crystal, the cations and anions are linked through N-H...Cl and O-H...Cl hydrogen bonds. There are also [pi]-[pi] contacts [centroid-centroid distance = 3.788 (3) Å] and a number of C-H...O and C-H...Cl interactions are present, consolidating the formation of a three-dimensional structure.

Comment top

Hydrogen bond based organic–inorganic hybrid materials are receiving continuous interest because of their structural, magnetic, optical and electrical properties (Yao et al., 2010; Sanchez et al., 2011; Pardo et al., 2011). An interesting approach for the preparation of such materials consists in the utilization of supramolecular synthons containing charge-assisted N+–H···Cl- hydrogen bonds, through which organic cations and anionic metal complexes are linked to form crystalline organic–inorganic hybrid solids (Kumar et al., 2006; Adams et al., 2005,2006; Maris, 2008). As a further contribution we report herein on the crystal structure of the title compound.

The asymmetric unit of the title compound consists of one threefold charged organic cation in a general position and two independent [PdCl4]2- dianions, one of which is located on a crystallographic inversion center (Fig. 1). In the cation, the pyridinium rings attached to the central 2-ammoniumethanol fragment show an anti conformation, as indicated by the C8—C1—C2—C3 torsion angle of -178.1 (4)°, and form a dihedral angle of 25.7 (2)°. The Pd atoms have square-planar coordination environments with Pd—Cl distances ranging from 2.2760 (10) to 2.3056 (11) Å.

In the crystal, the cations and anions are linked by N+—H···Cl- and O—H···Cl- hydrogen bonds (Table 1 and Fig. 2). There are π—π interactions present involving inversion related pyridinium rings [Cg···Cgi distance = 3.788 (3) Å; Cg centroid of the N3,C3-C7 ring; symmetry code (i) -x, -y+2, -z]. There are also a number of C-H···O and C-H···Cl interactions present, consolidating the formation of a three-dimensional structure (Table 1 and Fig. 2).

Related literature top

For potential applications of organic–inorganic hybrid materials with magnetic, optical and electrical properties, see: Yao et al. (2010); Sanchez et al. (2011); Pardo et al. (2011). For related tetrachloridopalladate(II) compounds, see: Kumar et al. (2006); Adams et al. (2005, 2006); Maris (2008). For the synthesis of the ligand, see: Campos-Gaxiola et al. (2012).

Experimental top

The organic entities in the title compound are the product of partial hydrolysis starting from 2,4,5-tris(pyridin-4-yl)-4,5-dihydro-1,3-oxazole, which was synthesized according to a previously reported procedure (Campos-Gaxiola et al., 2012). For the preparation of the palladium complex, a solution of 2,4,5-tris(pyridin-4-yl)-4,5-dihydro-1,3-oxazole (0.05 g, 0.16 mmol) in methanol and concentrated HCl (37%, 3 ml) was added dropwise to a stirring solution of potassium tetrachloridopalladate (0.05 g, 0.16 mmol) in water (5 ml). The resulting yellow solution was stirred for 30 min at 333 K, whereupon the solution was left to evaporate slowly at room temperature. After two weeks, red crystals were isolated [Yield: 30%]. Spectroscopic and TGA data for the title compound are available in the archived CIF.

Refinement top

C bound H atoms were positioned geometrically and constrained using the riding-model approximation [aryl C—H = 0.93 Å and Uiso(H) = 1.2Ueq(C)]. The N—H and O—H hydrogen atoms were located in difference Fourier maps and were refined with distance restraints: N-H = 0.86 (1) for NH3+ H atoms and 0.84 (1) Å for O—H and pyN-H+ H atoms, with Uiso(H) = 1.2Ueq(O,N).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the asymmetric unit of the title compound, with the atom-labelling. Displacement ellipsoids are drawn at the 50% probability level. [symmetry code: (i) -x + 1, -y + 2, -z + 1].
[Figure 2] Fig. 2. A view along the a axis of the crystal packing of the title compound, with the hydrogen bonds shown as dashed lines (see Table 1 for details).
Bis[(1RS,2RS)-4,4'-(1-azaniumyl-2-hydroxyethane-1,2- diyl)dipyridinium] tris[tetrachloridopalladate(II)] top
Crystal data top
(C12H16N3O)2[PdCl4]3Z = 1
Mr = 1181.16F(000) = 576
Triclinic, P1Dx = 2.166 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.6970 (7) ÅCell parameters from 3544 reflections
b = 7.7339 (7) Åθ = 2.7–28.2°
c = 15.7254 (13) ŵ = 2.40 mm−1
α = 84.541 (2)°T = 100 K
β = 81.314 (2)°Rectangular prism, red
γ = 78.717 (1)°0.29 × 0.22 × 0.17 mm
V = 905.40 (14) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer		3143 independent reflections
Radiation source: fine-focus sealed tube2927 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.019
phi and ω scansθmax = 25.0°, θmin = 1.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −9→7
Tmin = 0.543, Tmax = 0.686k = −9→9
5043 measured reflectionsl = −16→18
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)] = 0.032Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.077H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0322P)2 + 2.1607P]
where P = (Fo2 + 2Fc2)/3
3143 reflections(Δ/σ)max < 0.001
232 parametersΔρmax = 1.23 e Å−3
6 restraintsΔρmin = −0.48 e Å−3
Crystal data top
(C12H16N3O)2[PdCl4]3γ = 78.717 (1)°
Mr = 1181.16V = 905.40 (14) Å3
Triclinic, P1Z = 1
a = 7.6970 (7) ÅMo Kα radiation
b = 7.7339 (7) ŵ = 2.40 mm−1
c = 15.7254 (13) ÅT = 100 K
α = 84.541 (2)°0.29 × 0.22 × 0.17 mm
β = 81.314 (2)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		3143 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2927 reflections with I > 2σ(I)
Tmin = 0.543, Tmax = 0.686Rint = 0.019
5043 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.032H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.077Δρmax = 1.23 e Å−3
S = 1.07Δρmin = −0.48 e Å−3
3143 reflectionsAbsolute structure: ?
232 parametersFlack parameter: ?
6 restraintsRogers parameter: ?
Special details top

Experimental. Spectroscopic and TGA data for the title compound: IR(KBr, cm-1): 3440, 3211, 3064, 2937, 2888, 1669, 1630, 1509, 1421, 1358, 1294, 999, 832. TGA: Calcd. for HCl: 3.08. Found: 3.26% (303–448 K); Calcd. for PdCl2: 15.49. Found: 15.85% (448–523 K).

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

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
xyzUiso*/Ueq
O1−0.0806 (4)0.6561 (4)0.14345 (19)0.0254 (10)
N1−0.3332 (5)0.8197 (5)0.2757 (2)0.0243 (12)
N20.1298 (5)0.3847 (5)0.4127 (2)0.0229 (11)
N3−0.2750 (5)1.2478 (5)0.0153 (2)0.0209 (11)
C1−0.1380 (6)0.8184 (6)0.2689 (3)0.0240 (12)
C2−0.0541 (6)0.8136 (6)0.1750 (3)0.0255 (12)
C3−0.1379 (6)0.9732 (6)0.1205 (3)0.0221 (12)
C4−0.2352 (6)0.9472 (6)0.0571 (3)0.0269 (14)
C5−0.3016 (6)1.0887 (6)0.0040 (3)0.0250 (12)
C6−0.1864 (6)1.2805 (6)0.0775 (3)0.0239 (12)
C7−0.1160 (6)1.1430 (6)0.1307 (3)0.0219 (12)
C8−0.0458 (6)0.6609 (6)0.3204 (3)0.0229 (12)
C9−0.1047 (6)0.5003 (6)0.3334 (3)0.0259 (12)
C10−0.0142 (6)0.3628 (6)0.3807 (3)0.0233 (12)
C110.1937 (6)0.5346 (6)0.4001 (3)0.0226 (12)
C120.1067 (6)0.6767 (6)0.3539 (3)0.0234 (12)
Pd10.500001.000000.500000.0165 (1)
Cl10.53138 (14)0.71363 (13)0.46422 (7)0.0220 (3)
Cl20.19678 (14)1.02190 (13)0.52122 (7)0.0250 (3)
Pd20.39126 (4)0.32273 (4)0.19078 (2)0.0158 (1)
Cl30.56147 (14)0.25575 (14)0.30002 (7)0.0247 (3)
Cl40.30607 (16)0.05224 (14)0.21810 (8)0.0300 (3)
Cl50.23446 (15)0.37787 (13)0.07476 (7)0.0241 (3)
Cl60.46316 (15)0.60016 (13)0.16265 (7)0.0261 (3)
H1−0.120400.928900.291900.0290*
H1'0.014 (4)0.584 (5)0.130 (3)0.0380*
H1A−0.391 (6)0.924 (3)0.265 (3)0.0360*
H1B−0.361 (7)0.742 (5)0.247 (3)0.0360*
H1C−0.374 (7)0.788 (7)0.3275 (12)0.0360*
H20.077100.812000.171300.0300*
H2'0.175 (6)0.299 (4)0.444 (3)0.0350*
H3'−0.309 (6)1.338 (4)−0.016 (3)0.0310*
H4−0.256000.832500.050300.0320*
H5−0.366401.07190−0.040500.0300*
H6−0.172901.397600.084500.0290*
H7−0.052101.163900.174700.0260*
H9−0.207000.485700.309600.0310*
H10−0.054100.253000.390500.0280*
H110.298800.543300.423000.0280*
H120.150600.784500.345000.0280*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0310 (18)0.0191 (15)0.0257 (17)−0.0019 (13)−0.0048 (14)−0.0037 (13)
N10.023 (2)0.025 (2)0.022 (2)0.0003 (16)−0.0014 (16)0.0011 (16)
N20.022 (2)0.0226 (19)0.0203 (19)0.0029 (15)−0.0056 (15)0.0074 (15)
N30.0170 (18)0.0227 (19)0.0197 (19)−0.0009 (15)−0.0016 (15)0.0078 (15)
C10.022 (2)0.026 (2)0.025 (2)−0.0060 (18)−0.0078 (18)0.0033 (19)
C20.022 (2)0.026 (2)0.028 (2)−0.0038 (18)−0.0023 (19)−0.0030 (19)
C30.022 (2)0.025 (2)0.019 (2)−0.0064 (18)−0.0026 (18)0.0042 (18)
C40.036 (3)0.021 (2)0.025 (2)−0.009 (2)−0.005 (2)0.0004 (18)
C50.026 (2)0.032 (2)0.020 (2)−0.011 (2)−0.0088 (19)0.0037 (19)
C60.029 (2)0.022 (2)0.021 (2)−0.0080 (19)−0.0011 (19)0.0007 (18)
C70.022 (2)0.029 (2)0.018 (2)−0.0110 (18)−0.0060 (17)0.0006 (18)
C80.024 (2)0.023 (2)0.022 (2)−0.0039 (18)−0.0070 (18)0.0019 (18)
C90.029 (2)0.023 (2)0.028 (2)−0.0077 (19)−0.010 (2)0.0029 (19)
C100.025 (2)0.018 (2)0.026 (2)−0.0040 (18)−0.0014 (19)−0.0009 (18)
C110.018 (2)0.030 (2)0.019 (2)−0.0020 (18)−0.0055 (18)0.0026 (18)
C120.022 (2)0.026 (2)0.023 (2)−0.0082 (18)−0.0049 (18)0.0052 (18)
Pd10.0180 (2)0.0144 (2)0.0185 (2)−0.0050 (2)−0.0073 (2)0.0038 (2)
Cl10.0290 (6)0.0162 (5)0.0224 (5)−0.0075 (4)−0.0071 (4)0.0026 (4)
Cl20.0193 (5)0.0206 (5)0.0357 (6)−0.0063 (4)−0.0081 (4)0.0079 (4)
Pd20.0177 (2)0.0147 (2)0.0151 (2)−0.0023 (1)−0.0044 (1)0.0000 (1)
Cl30.0261 (6)0.0283 (5)0.0216 (5)−0.0071 (4)−0.0102 (4)0.0034 (4)
Cl40.0375 (6)0.0182 (5)0.0389 (7)−0.0095 (5)−0.0204 (5)0.0085 (5)
Cl50.0303 (6)0.0203 (5)0.0245 (5)−0.0067 (4)−0.0132 (4)0.0031 (4)
Cl60.0338 (6)0.0204 (5)0.0286 (6)−0.0114 (4)−0.0137 (5)0.0039 (4)
Geometric parameters (Å, º) top
Pd1—Cl22.2821 (11)C1—C81.514 (7)
Pd1—Cl1i2.2950 (10)C2—C31.526 (7)
Pd1—Cl12.2950 (10)C3—C41.385 (7)
Pd1—Cl2i2.2821 (11)C3—C71.383 (6)
Pd2—Cl42.2960 (12)C4—C51.376 (7)
Pd2—Cl52.2985 (12)C6—C71.366 (7)
Pd2—Cl32.2760 (12)C8—C91.391 (7)
Pd2—Cl62.3056 (11)C8—C121.388 (7)
O1—C21.419 (6)C9—C101.373 (7)
O1—H1'0.84 (4)C11—C121.375 (7)
N1—C11.488 (6)C1—H11.0000
N2—C101.330 (6)C2—H21.0000
N2—C111.332 (6)C4—H40.9500
N3—C51.319 (6)C5—H50.9500
N3—C61.342 (6)C6—H60.9500
N1—H1C0.86 (2)C7—H70.9500
N1—H1A0.86 (3)C9—H90.9500
N1—H1B0.86 (4)C10—H100.9500
N2—H2'0.84 (4)C11—H110.9500
N3—H3'0.84 (4)C12—H120.9500
C1—C21.521 (7)
Cl1i—Pd1—Cl2i89.74 (4)C3—C4—C5119.5 (4)
Cl1—Pd1—Cl2i90.26 (4)N3—C5—C4119.6 (4)
Cl1—Pd1—Cl289.74 (4)N3—C6—C7119.1 (4)
Cl1—Pd1—Cl1i180.00C3—C7—C6120.0 (4)
Cl1i—Pd1—Cl290.26 (4)C1—C8—C9122.8 (4)
Cl2—Pd1—Cl2i180.00C9—C8—C12118.9 (4)
Cl4—Pd2—Cl589.59 (4)C1—C8—C12118.3 (4)
Cl3—Pd2—Cl692.45 (4)C8—C9—C10119.6 (4)
Cl3—Pd2—Cl489.51 (4)N2—C10—C9119.4 (4)
Cl4—Pd2—Cl6177.33 (4)N2—C11—C12119.7 (4)
Cl5—Pd2—Cl688.58 (4)C8—C12—C11119.3 (4)
Cl3—Pd2—Cl5176.06 (4)C8—C1—H1109.00
C2—O1—H1'114 (3)N1—C1—H1109.00
C10—N2—C11123.0 (4)C2—C1—H1109.00
C5—N3—C6123.1 (4)C3—C2—H2109.00
C1—N1—H1C110 (4)C1—C2—H2109.00
C1—N1—H1A111 (3)O1—C2—H2109.00
H1A—N1—H1B113 (4)C3—C4—H4120.00
C1—N1—H1B115 (4)C5—C4—H4120.00
H1B—N1—H1C102 (5)N3—C5—H5120.00
H1A—N1—H1C106 (5)C4—C5—H5120.00
C10—N2—H2'115 (3)C7—C6—H6120.00
C11—N2—H2'122 (3)N3—C6—H6121.00
C6—N3—H3'113 (3)C3—C7—H7120.00
C5—N3—H3'124 (3)C6—C7—H7120.00
N1—C1—C8111.3 (4)C8—C9—H9120.00
C2—C1—C8109.4 (4)C10—C9—H9120.00
N1—C1—C2110.0 (4)N2—C10—H10120.00
O1—C2—C3109.6 (4)C9—C10—H10120.00
O1—C2—C1107.9 (4)N2—C11—H11120.00
C1—C2—C3111.6 (4)C12—C11—H11120.00
C2—C3—C7122.2 (4)C11—C12—H12120.00
C4—C3—C7118.7 (4)C8—C12—H12120.00
C2—C3—C4119.1 (4)
C11—N2—C10—C9−1.0 (7)C1—C2—C3—C4−114.2 (5)
C10—N2—C11—C121.7 (7)C1—C2—C3—C767.6 (6)
C6—N3—C5—C4−0.7 (7)C2—C3—C4—C5−175.9 (4)
C5—N3—C6—C71.7 (7)C7—C3—C4—C52.4 (7)
N1—C1—C2—O1−61.0 (5)C2—C3—C7—C6176.8 (4)
N1—C1—C2—C359.5 (5)C4—C3—C7—C6−1.4 (7)
C8—C1—C2—O161.5 (5)C3—C4—C5—N3−1.4 (7)
C8—C1—C2—C3−178.1 (4)N3—C6—C7—C3−0.6 (7)
N1—C1—C8—C930.7 (6)C1—C8—C9—C10179.9 (4)
N1—C1—C8—C12−151.1 (4)C12—C8—C9—C101.7 (7)
C2—C1—C8—C9−91.0 (5)C1—C8—C12—C11−179.3 (4)
C2—C1—C8—C1287.2 (5)C9—C8—C12—C11−1.0 (7)
O1—C2—C3—C45.3 (6)C8—C9—C10—N2−0.7 (7)
O1—C2—C3—C7−172.9 (4)N2—C11—C12—C8−0.6 (7)
Symmetry code: (i) −x+1, −y+2, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1′···Cl50.84 (4)2.22 (4)3.047 (3)168 (4)
N1—H1A···Cl3ii0.86 (3)2.62 (2)3.355 (4)145 (4)
N1—H1A···Cl4ii0.86 (3)2.54 (4)3.203 (4)135 (4)
N1—H1B···Cl6iii0.86 (4)2.49 (5)3.310 (4)160 (4)
N1—H1C···Cl1iii0.86 (2)2.22 (2)3.080 (3)177 (6)
N2—H2′···Cl2iv0.84 (4)2.35 (4)3.137 (4)157 (4)
N3—H3′···Cl5v0.84 (4)2.44 (4)3.150 (4)143 (4)
N3—H3′···Cl6v0.84 (4)2.71 (5)3.353 (4)135 (3)
C4—H4···Cl5vi0.952.643.406 (5)139
C6—H6···O1vii0.952.543.454 (6)161
C9—H9···Cl3iii0.952.783.599 (5)145
C10—H10···Cl2viii0.952.753.649 (5)159
C11—H11···Cl10.952.613.486 (5)154
C11—H11···Cl1ix0.952.803.422 (5)124
Symmetry codes: (ii) x−1, y+1, z; (iii) x−1, y, z; (iv) x, y−1, z; (v) −x, −y+2, −z; (vi) −x, −y+1, −z; (vii) x, y+1, z; (viii) −x, −y+1, −z+1; (ix) −x+1, −y+1, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1'···Cl50.84 (4)2.22 (4)3.047 (3)168 (4)
N1—H1A···Cl3i0.86 (3)2.62 (2)3.355 (4)145 (4)
N1—H1A···Cl4i0.86 (3)2.54 (4)3.203 (4)135 (4)
N1—H1B···Cl6ii0.86 (4)2.49 (5)3.310 (4)160 (4)
N1—H1C···Cl1ii0.86 (2)2.22 (2)3.080 (3)177 (6)
N2—H2'···Cl2iii0.84 (4)2.35 (4)3.137 (4)157 (4)
N3—H3'···Cl5iv0.84 (4)2.44 (4)3.150 (4)143 (4)
N3—H3'···Cl6iv0.84 (4)2.71 (5)3.353 (4)135 (3)
C4—H4···Cl5v0.952.643.406 (5)139
C6—H6···O1vi0.952.543.454 (6)161
C9—H9···Cl3ii0.952.783.599 (5)145
C10—H10···Cl2vii0.952.753.649 (5)159
C11—H11···Cl10.952.613.486 (5)154
C11—H11···Cl1viii0.952.803.422 (5)124
Symmetry codes: (i) x−1, y+1, z; (ii) x−1, y, z; (iii) x, y−1, z; (iv) −x, −y+2, −z; (v) −x, −y+1, −z; (vi) x, y+1, z; (vii) −x, −y+1, −z+1; (viii) −x+1, −y+1, −z+1.
Acknowledgements top

This work was supported financially by the Universidad Autónoma de Sinaloa (PROFAPI 2012/032).

references
References top

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