supplementary materials


rz5058 scheme

Acta Cryst. (2013). E69, m292-m293    [ doi:10.1107/S1600536813010738 ]

catena-Poly[[bis(2-methoxyaniline-[kappa]N)cadmium]-di-[mu]-thiocyanato-[kappa]2N:S;[kappa]2S:N]

R. Chemli, S. Kamoun and T. Roisnel

Abstract top

The structure of the title compound, [Cd(NCS)2(C7H9NO)2]n, consists of cadmium-thiocyanate layers parallel to the ab plane. Pairs of CdII ions are bridged by two end-to-end inversely bridging [mu]-NCS-N:S thiocyanate groups, forming a two-dimensional network with the remaining two trans positions of the octahedrally coordinated CdII ions occupied by the N atoms of two neutral 2-methoxyaniline ligands. The crystal structure is stabilized by intralayer N-H...S hydrogen bonds.

Comment top

The crystal engineering of inorganic-organic hybrid coordination polymers is currently one of the most active fields in coordination chemistry, supramolecular and materials chemistry. These compounds attract significant attention for their architectures and topologies (Yang et al., 2001). Hybrid inorganic-organic thiocyanate materials exhibit interesting physical properties such electrical conductivity and dielectric relaxation process (Karoui et al., 2013) and may have potential applications in non-linear optics and luminescence (Chen et al., 2000; Bai et al., 2011). Herein we report the structure of a new polymeric hybrid title compound

As shown in Fig. 1, each cadmium atom, which sits on general position, is coordinated by two trans N-bonded and two trans S-bonded thiocyanato anions. Two trans-coordinated 2-methoxy aniline ligands complete the octahedral coordination geometry around cadmium. The crystal structure of the title compound consists of both simply and doubly µ-1,3-SCN–bridged two dimensional networks parallel to the ab plane with terminal neutral 2-methoxyaniline ligands (Fig. 2). In the CdN4S2 core, the Cd—N and Cd—S bonds span the range 2.2724 (19)–2.3718 (17) Å and 2.7306 (6)–2.7449 (6) Å, respectively (Table 1). These values are in good agreement with those observed in other similar complexes (Wöhlert et al., 2012, 2013; Yang et al., 2001). The bond angles involving the cadmium(II) cation range from 84.29 (6) to 95.50 (7)° and from 174.91 (2) to 175.76 (6)°. The double-bridging role of S1/C1/N1 anions gives rise to eight-membered Cd2(SCN)2 rings in a chair conformation because of the almost linear SCN groups (S1–C1–N1 angle = 178.76 (21)°). The distance between adjacent Cd atoms in the Cd2(SCN)2 rings is 5.9127 (4) Å. Again, these rings built up a 2-D sheet through their corner-sharing action at the two cadmium atoms via the linear S2/C2/N2 anions (S1–C1–N1 angle = 177.96 (21)°) and give rise to thirty-membered [Cd6(µ-SCN-N,S)8] macrocycles as subunits, as shown in Fig. 2. The bond angles in the phenyl groups deviate significantly from the idealized value of 120° due to the effect of the substituent. In fact, it was established that the angular deformations of phenyl groups can be described as a sum of the effects of the different substituents (Domenicano & Murray-Rust, 1979). The phenyl rings of both independent 2-methoxyaniline ligands are planar with the greatest deviation from the six-atoms least-square plane of 0.0029 Å and 0.0073 Å. They are well ordered with C–C–C angles in agreement with the expected sp2 hybridation. The π-π interactions between phenyl rings may be neglected (>4 Å); in fact the shortest distances between the centroids of the rings are: Cg1 ··· Cg1i = 5.6130 (14) Å; Cg1 ··· Cg2ii = 5.5949 (14) Å (Cg1 and Cg2 are the centroids of the C12–C17 and C22–C27 rings, respectively; symmetry codes: (i) -0.5+x, +y, 1.5-z; 2.-x, -y, 1.-z). The major contributions to the cohesion and the stability of the polymeric structure is the presence of intralayer N—H···S hydrogen bonds which include two relatively long contacts, with H···S and N..S distances ranging from 2.50 to 2.66 Å and 3.4182 (17) Å to 3.5637 (18) Å, respectively (Table 2).

Related literature top

For related structures, see: Wöhlert et al. (2012, 2013); Bai et al. (2011); Yang et al. (2001). For HSCN synthesis, see: Bartlett et al. (1969). For the effects of substituents on the internal angles of the benzene ring, see: Domenicano & Murray-Rust (1979). For non-linear optical and luminescence properties of related compounds, see: Chen et al. (2000); Bai et al. (2011). For electric and dielectric properties of related compounds, see: Karoui et al. (2013).

Experimental top

To 25 ml of an aqueous solution of thiocyanic acid (0.8 M) prepared using the published procedure (Bartlett et al., 1969) an appropriate amount of cadmium carbonate (1.664 g, 10 mmol) was added and refluxed for 3 h. After cooling, 25 ml of methanol and 2.3 ml of a solution of 2-methoxyaniline (8.64 M) was added. The resulting solution was heated under reflux for 1 h and left to stand at ambient temperature. Well shaped colourless crystals were obtained after 2 h on slow evaporation of the solvent. They were washed with diethyl ether and dried over P2O5.

Refinement top

All H atoms were positioned geometrically and allowed to ride on their parent atoms, with C—H = 0.95-0.98 Å, N—H = 0.92 Å, and with Uiso(H) = 1.2Ueq(C, N).

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: SAINT (Bruker, 2011); data reduction: SAINT (Bruker, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Berndt, 2001) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Crystal structure of the title compound, showing the coordination around the Cd2+ cation with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. View at z=0 of the two-dimensional layer structure of the inorganic coordination polymer parallel to the ab plane. The organic ligands are omitted for clarity.
catena-Poly[[bis(2-methoxyaniline-κN)cadmium]-di-µ-thiocyanato-κ2N:S;κ2S:N] top
Crystal data top
[Cd(NCS)2(C7H9NO)2]F(000) = 1904
Mr = 474.89Dx = 1.660 Mg m3
Dm = 1.593 Mg m3
Dm measured by flotation
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 5155 reflections
a = 6.6860 (2) Åθ = 3.1–27.4°
b = 23.3658 (7) ŵ = 1.39 mm1
c = 24.3281 (8) ÅT = 150 K
V = 3800.6 (2) Å3Prism, colourless
Z = 80.33 × 0.18 × 0.11 mm
Data collection top
Bruker APEXII
diffractometer
3262 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
Graphite monochromatorθmax = 27.5°, θmin = 3.1°
CCD rotation images, thin slices scansh = 88
Absorption correction: multi-scan
(SADABS; Bruker, 2011)
k = 2930
Tmin = 0.741, Tmax = 0.859l = 3120
16897 measured reflections2 standard reflections every 120 min
4210 independent reflections
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)] = 0.025Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.055H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0184P)2 + 1.4548P]
where P = (Fo2 + 2Fc2)/3
4210 reflections(Δ/σ)max = 0.004
228 parametersΔρmax = 0.35 e Å3
0 restraintsΔρmin = 0.38 e Å3
Crystal data top
[Cd(NCS)2(C7H9NO)2]V = 3800.6 (2) Å3
Mr = 474.89Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 6.6860 (2) ŵ = 1.39 mm1
b = 23.3658 (7) ÅT = 150 K
c = 24.3281 (8) Å0.33 × 0.18 × 0.11 mm
Data collection top
Bruker APEXII
diffractometer
3262 reflections with I > 2σ(I)
Absorption correction: multi-scan
(SADABS; Bruker, 2011)
Rint = 0.031
Tmin = 0.741, Tmax = 0.859θmax = 27.5°
16897 measured reflections2 standard reflections every 120 min
4210 independent reflections intensity decay: ?
Refinement top
R[F2 > 2σ(F2)] = 0.025H-atom parameters constrained
wR(F2) = 0.055Δρmax = 0.35 e Å3
S = 1.02Δρmin = 0.38 e Å3
4210 reflectionsAbsolute structure: ?
228 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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
xyzUiso*/Ueq
Cd10.99993 (2)0.126200 (7)0.508711 (7)0.02024 (6)
S10.68873 (8)0.06757 (2)0.53717 (3)0.03279 (16)
C10.7845 (3)0.00256 (9)0.53832 (8)0.0191 (5)
N10.8515 (3)0.04293 (8)0.54015 (8)0.0253 (4)
S21.17331 (8)0.32408 (2)0.44237 (3)0.02739 (14)
N21.1259 (3)0.21155 (8)0.48030 (8)0.0266 (4)
C21.1461 (3)0.25807 (9)0.46565 (9)0.0193 (5)
N111.1959 (2)0.13518 (7)0.58919 (7)0.0213 (4)
H11A1.32470.14400.57890.026*
H11B1.14780.16570.60920.026*
C121.2028 (3)0.08631 (9)0.62450 (9)0.0220 (5)
C131.3485 (3)0.04507 (10)0.61900 (10)0.0312 (6)
H131.45200.04980.59260.037*
C141.3446 (4)0.00363 (11)0.65207 (11)0.0412 (7)
H141.44660.03170.64880.049*
C151.1926 (5)0.01091 (11)0.68948 (11)0.0441 (7)
H151.18890.04450.71150.053*
C161.0444 (4)0.03030 (12)0.69545 (9)0.0362 (6)
H160.93940.02490.72130.043*
C171.0510 (3)0.07931 (10)0.66349 (9)0.0258 (5)
O180.9195 (2)0.12405 (7)0.66597 (7)0.0344 (4)
C190.7522 (4)0.11868 (13)0.70215 (11)0.0478 (8)
H19A0.67970.08330.69380.072*
H19B0.66280.15150.69720.072*
H19C0.79940.11760.74030.072*
N210.8084 (3)0.10925 (8)0.42829 (7)0.0240 (4)
H21A0.87310.08130.40850.029*
H21B0.68790.09410.43930.029*
C220.7653 (3)0.15518 (10)0.39121 (9)0.0230 (5)
C230.5968 (3)0.18854 (10)0.39643 (9)0.0281 (5)
H230.50260.18050.42460.034*
C240.5637 (4)0.23401 (11)0.36050 (10)0.0344 (6)
H240.44660.25680.36400.041*
C250.7010 (4)0.24592 (11)0.31981 (10)0.0380 (6)
H250.67860.27710.29550.046*
C260.8727 (4)0.21251 (11)0.31418 (9)0.0346 (6)
H260.96740.22090.28620.042*
C270.9044 (3)0.16704 (10)0.34953 (9)0.0269 (5)
O281.0642 (2)0.13068 (7)0.34823 (7)0.0348 (4)
C291.1988 (4)0.13507 (13)0.30289 (10)0.0446 (7)
H29A1.12410.13120.26840.067*
H29B1.29920.10460.30530.067*
H29C1.26550.17240.30380.067*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cd10.02022 (9)0.01308 (9)0.02743 (10)0.00211 (6)0.00012 (7)0.00258 (7)
S10.0237 (3)0.0153 (3)0.0594 (4)0.0043 (2)0.0168 (3)0.0044 (3)
C10.0164 (9)0.0193 (12)0.0217 (11)0.0047 (9)0.0036 (9)0.0024 (10)
N10.0238 (9)0.0161 (10)0.0361 (11)0.0001 (8)0.0062 (9)0.0016 (9)
S20.0211 (3)0.0175 (3)0.0435 (3)0.0045 (2)0.0093 (3)0.0096 (3)
N20.0265 (10)0.0169 (10)0.0364 (11)0.0047 (8)0.0035 (9)0.0010 (9)
C20.0143 (9)0.0202 (12)0.0235 (11)0.0014 (9)0.0001 (9)0.0028 (10)
N110.0192 (8)0.0177 (10)0.0272 (10)0.0018 (8)0.0048 (8)0.0019 (8)
C120.0241 (10)0.0196 (11)0.0224 (11)0.0026 (9)0.0044 (9)0.0025 (10)
C130.0339 (12)0.0283 (13)0.0314 (13)0.0025 (11)0.0080 (11)0.0051 (12)
C140.0588 (17)0.0254 (14)0.0392 (15)0.0107 (13)0.0238 (14)0.0068 (13)
C150.077 (2)0.0220 (14)0.0334 (15)0.0083 (14)0.0267 (15)0.0048 (12)
C160.0501 (15)0.0380 (16)0.0205 (12)0.0184 (13)0.0058 (11)0.0031 (12)
C170.0309 (11)0.0254 (13)0.0211 (11)0.0053 (10)0.0024 (10)0.0010 (11)
O180.0304 (8)0.0399 (11)0.0330 (9)0.0006 (8)0.0131 (8)0.0038 (8)
C190.0336 (14)0.070 (2)0.0400 (16)0.0100 (14)0.0149 (12)0.0017 (16)
N210.0248 (9)0.0219 (10)0.0253 (10)0.0043 (8)0.0037 (8)0.0030 (9)
C220.0289 (11)0.0201 (12)0.0201 (11)0.0065 (10)0.0032 (9)0.0052 (10)
C230.0294 (12)0.0292 (13)0.0259 (12)0.0053 (11)0.0023 (10)0.0073 (11)
C240.0422 (13)0.0243 (13)0.0366 (14)0.0016 (12)0.0112 (12)0.0102 (12)
C250.0625 (17)0.0245 (14)0.0270 (13)0.0068 (13)0.0123 (13)0.0007 (12)
C260.0503 (15)0.0342 (15)0.0194 (12)0.0115 (13)0.0036 (11)0.0036 (12)
C270.0312 (12)0.0263 (13)0.0231 (12)0.0055 (11)0.0005 (10)0.0060 (11)
O280.0319 (8)0.0434 (11)0.0290 (9)0.0008 (8)0.0089 (7)0.0014 (8)
C290.0358 (14)0.066 (2)0.0321 (14)0.0049 (14)0.0089 (12)0.0082 (14)
Geometric parameters (Å, º) top
Cd1—N22.2724 (19)C16—H160.9500
Cd1—N12.3142 (18)C17—O181.367 (3)
Cd1—N112.3653 (17)O18—C191.429 (3)
Cd1—N212.3718 (17)C19—H19A0.9800
Cd1—S1i2.7306 (6)C19—H19B0.9800
Cd1—S2ii2.7449 (6)C19—H19C0.9800
S1—C11.649 (2)N21—C221.431 (3)
S1—Cd1i2.7306 (6)N21—H21A0.9200
C1—N11.154 (3)N21—H21B0.9200
S2—C21.653 (2)C22—C231.376 (3)
S2—Cd1iii2.7449 (5)C22—C271.403 (3)
N2—C21.152 (3)C23—C241.394 (3)
N11—C121.430 (3)C23—H230.9500
N11—H11A0.9200C24—C251.379 (3)
N11—H11B0.9200C24—H240.9500
C12—C131.377 (3)C25—C261.395 (3)
C12—C171.399 (3)C25—H250.9500
C13—C141.394 (3)C26—C271.383 (3)
C13—H130.9500C26—H260.9500
C14—C151.375 (4)C27—O281.365 (3)
C14—H140.9500O28—C291.427 (3)
C15—C161.389 (4)C29—H29A0.9800
C15—H150.9500C29—H29B0.9800
C16—C171.385 (3)C29—H29C0.9800
N2—Cd1—N1175.76 (6)O18—C17—C16125.9 (2)
N2—Cd1—N1188.20 (6)O18—C17—C12114.0 (2)
N1—Cd1—N1192.22 (6)C16—C17—C12120.0 (2)
N2—Cd1—N2195.50 (7)C17—O18—C19117.6 (2)
N1—Cd1—N2184.29 (6)O18—C19—H19A109.5
N11—Cd1—N21175.44 (6)O18—C19—H19B109.5
N2—Cd1—S1i91.92 (5)H19A—C19—H19B109.5
N1—Cd1—S1i92.31 (4)O18—C19—H19C109.5
N11—Cd1—S1i87.74 (4)H19A—C19—H19C109.5
N21—Cd1—S1i89.47 (5)H19B—C19—H19C109.5
N2—Cd1—S2ii93.16 (5)C22—N21—Cd1120.21 (13)
N1—Cd1—S2ii82.60 (4)C22—N21—H21A107.3
N11—Cd1—S2ii92.54 (4)Cd1—N21—H21A107.3
N21—Cd1—S2ii89.92 (5)C22—N21—H21B107.3
S1i—Cd1—S2ii174.914 (18)Cd1—N21—H21B107.3
C1—S1—Cd1i99.97 (7)H21A—N21—H21B106.9
N1—C1—S1178.8 (2)C23—C22—C27119.8 (2)
C1—N1—Cd1158.10 (18)C23—C22—N21122.1 (2)
C2—S2—Cd1iii109.52 (7)C27—C22—N21118.0 (2)
C2—N2—Cd1164.95 (17)C22—C23—C24120.3 (2)
N2—C2—S2178.0 (2)C22—C23—H23119.9
C12—N11—Cd1116.38 (13)C24—C23—H23119.9
C12—N11—H11A108.2C25—C24—C23119.9 (2)
Cd1—N11—H11A108.2C25—C24—H24120.0
C12—N11—H11B108.2C23—C24—H24120.0
Cd1—N11—H11B108.2C24—C25—C26120.4 (2)
H11A—N11—H11B107.3C24—C25—H25119.8
C13—C12—C17119.8 (2)C26—C25—H25119.8
C13—C12—N11121.6 (2)C27—C26—C25119.7 (2)
C17—C12—N11118.52 (19)C27—C26—H26120.2
C12—C13—C14120.1 (2)C25—C26—H26120.2
C12—C13—H13119.9O28—C27—C26125.7 (2)
C14—C13—H13119.9O28—C27—C22114.4 (2)
C15—C14—C13119.8 (2)C26—C27—C22120.0 (2)
C15—C14—H14120.1C27—O28—C29117.82 (19)
C13—C14—H14120.1O28—C29—H29A109.5
C14—C15—C16120.7 (2)O28—C29—H29B109.5
C14—C15—H15119.6H29A—C29—H29B109.5
C16—C15—H15119.6O28—C29—H29C109.5
C17—C16—C15119.4 (2)H29A—C29—H29C109.5
C17—C16—H16120.3H29B—C29—H29C109.5
C15—C16—H16120.3
N11—Cd1—N1—C1141.7 (4)C13—C12—C17—C161.7 (3)
N21—Cd1—N1—C135.3 (4)N11—C12—C17—C16175.03 (19)
S1i—Cd1—N1—C153.9 (4)C16—C17—O18—C194.3 (3)
S2ii—Cd1—N1—C1126.0 (4)C12—C17—O18—C19176.0 (2)
N11—Cd1—N2—C2122.1 (7)N2—Cd1—N21—C2216.79 (16)
N21—Cd1—N2—C260.6 (7)N1—Cd1—N21—C22158.96 (16)
S1i—Cd1—N2—C2150.2 (7)S1i—Cd1—N21—C22108.66 (15)
S2ii—Cd1—N2—C229.6 (7)S2ii—Cd1—N21—C2276.39 (15)
N2—Cd1—N11—C12171.56 (15)Cd1—N21—C22—C2390.3 (2)
N1—Cd1—N11—C1212.66 (14)Cd1—N21—C22—C2787.6 (2)
S1i—Cd1—N11—C1279.56 (14)C27—C22—C23—C240.0 (3)
S2ii—Cd1—N11—C1295.35 (14)N21—C22—C23—C24177.95 (19)
Cd1—N11—C12—C1391.3 (2)C22—C23—C24—C250.5 (3)
Cd1—N11—C12—C1785.4 (2)C23—C24—C25—C260.4 (4)
C17—C12—C13—C140.2 (3)C24—C25—C26—C270.3 (4)
N11—C12—C13—C14176.4 (2)C25—C26—C27—O28179.3 (2)
C12—C13—C14—C151.3 (4)C25—C26—C27—C220.8 (3)
C13—C14—C15—C161.2 (4)C23—C22—C27—O28179.42 (19)
C14—C15—C16—C170.3 (4)N21—C22—C27—O282.6 (3)
C15—C16—C17—O18178.0 (2)C23—C22—C27—C260.6 (3)
C15—C16—C17—C121.7 (3)N21—C22—C27—C26177.39 (19)
C13—C12—C17—O18178.09 (19)C26—C27—O28—C298.1 (3)
N11—C12—C17—O185.2 (3)C22—C27—O28—C29172.00 (19)
Symmetry codes: (i) x+2, y, z+1; (ii) x1/2, y+1/2, z+1; (iii) x+1/2, y+1/2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N11—H11A···S2iii0.922.503.4182 (17)174
N21—H21B···S1iv0.922.663.5637 (18)169
N11—H11B···O180.922.282.641 (2)103
N21—H21A···O280.922.262.640 (2)104
Symmetry codes: (iii) x+1/2, y+1/2, z+1; (iv) x+1, y, z+1.
Selected bond lengths (Å) top
Cd1—N22.2724 (19)Cd1—N212.3718 (17)
Cd1—N12.3142 (18)Cd1—S1i2.7306 (6)
Cd1—N112.3653 (17)Cd1—S2ii2.7449 (6)
Symmetry codes: (i) x+2, y, z+1; (ii) x1/2, y+1/2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N11—H11A···S2iii0.922.503.4182 (17)174.3
N21—H21B···S1iv0.922.663.5637 (18)169.4
Symmetry codes: (iii) x+1/2, y+1/2, z+1; (iv) x+1, y, z+1.
Acknowledgements top

The authors gratefully acknowledge the support of the Tunisian Ministry of Higher Education and Scientific Research.

references
References top

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