catena-Poly[[{N,N-dimethyl-N′-[1-(pyridin-2-yl)ethyl­idene]ethane-1,2-diamine-κ3N,N′,N′′}(thio­cyanato-κN)cadmium]-μ-thio­cyanato-κ2S:N]

Suleiman Gwaram, N.; Khaledi, H.; Mohd Ali, H.

doi:10.1107/S1600536811010063

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 4| April 2011| Page m480

doi:10.1107/S1600536811010063

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catena-Poly[[{N,N-dimethyl-N′-[1-(pyridin-2-yl)ethylidene]ethane-1,2-diamine-κ³N,N′,N′′}(thiocyanato-κN)cadmium]-μ-thiocyanato-κ²S:N]

Nura Suleiman Gwaram,^a Hamid Khaledi ^a ^* and Hapipah Mohd Ali ^a

^aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: khaledi@siswa.um.edu.my

(Received 3 March 2011; accepted 17 March 2011; online 26 March 2011)

In the title compound, [Cd(NCS)₂(C₁₁H₁₇N₃)]_n, the Cd^II atom is octahedrally coordinated by the N,N′,N′′-tridentate Schiff base ligand and one terminal thiocyanate N atom. Two trans-N:S-bridging thiocyanates complete the N₅S donor set around the Cd atom. In the crystal, adjacent Cd^II ions are linked by the thiocyanate N:S-bridges into polymeric chains along the c axis.

Related literature

For the structures of some cadmium thiocyanate complexes with nitrogen-based ligands, see: Banerjee et al. (2005 ). For a singly bridged cadmium thiocyanate complex, see: Bose et al. (2004 ). For a triply bridged cadmium thiocyanate complex, see: Chen et al. (2002 ). For an S-bound terminal thiocyanate cadmium complex, see: Nfor et al. (2006 ).

Experimental

Crystal data

[Cd(NCS)₂(C₁₁H₁₇N₃)]
M_r = 419.84
Monoclinic, P 2₁ /c
a = 14.602 (2) Å
b = 9.5827 (14) Å
c = 12.8714 (19) Å
β = 107.483 (2)°
V = 1717.9 (4) Å³
Z = 4
Mo Kα radiation
μ = 1.51 mm⁻¹
T = 100 K
0.35 × 0.29 × 0.08 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.619, T_max = 0.889
19975 measured reflections
3756 independent reflections
3298 reflections with I > 2σ(I)
R_int = 0.047

Refinement

R[F² > 2σ(F²)] = 0.023
wR(F²) = 0.056
S = 1.07
3756 reflections
193 parameters
H-atom parameters constrained
Δρ_max = 0.54 e Å⁻³
Δρ_min = −0.73 e Å⁻³

Table 1
Selected bond lengths (Å)

Cd1—N4	2.2406 (18)
Cd1—N5	2.3008 (19)
Cd1—N2	2.3345 (17)
Cd1—N1	2.3801 (18)
Cd1—N3	2.3820 (19)
Cd1—S2	2.7803 (6)
Symmetry code: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: SHELXL97 and publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811010063/om2412sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811010063/om2412Isup2.hkl

checkCIF report

Comment top

Thiocyanate anion is known to bind the cadmium ion in different modes: terminal N-bound, terminal S-bound (Nfor et al. 2006) or N:S-bridging ligand. As a bridging ligand, it may give rise to a singly bridged (Bose et al. 2004), doubly bridged or triply bridged (Chen et al. 2002) cadmium complex. The title compound is a mixed-ligand cadmium complex with thiocyanate and the Schiff base N,N-dimethyl-N'-[methyl(2-pyridyl)methylene]ethane-1,2-diamine. Similar to what was observed in the cadmium thiocyanate adduct of the similar Schiff base, N,N-diethyl-N'-[methyl(2-pyridyl)methylene]ethane-1,2-diamine (Banerjee et al. 2005), the thiocyanate ions act as either bridging or terminal ligands. However, different from the doubly bridged dimeric structure of the former, in the present structure the bridging thiocyanate ligands singly bridge the adjacent metal centers, related by symmetry x, –y+1/2, z - 1/2, into infinite chains along the c axis. Within this coordination polymer, the Cd^II ions are separated by the distance of 8.0234 (9) Å. Two thiocyanate N:S-bridges, one terminal thiocyanate N atom and the N,N',N"-tridentate Schiff base make a distorted octahedral geometry around the Cd(II) atoms.

Related literature top

For the structures of some cadmium(II) thiocyanate complexes with nitrogen-based ligands, see: Banerjee et al. (2005). For a singly bridged cadmium(II) thiocyanate complex, see: Bose et al. (2004). For a triply bridged cadmium(II) thiocyanate complex, see: Chen et al. (2002). For an S-bound terminal thiocyanate cadmium complex, see: Nfor et al. (2006).

Experimental top

A mixture of 2-acetylpyridine (0.2 g, 1.65 mmol) and N,N-dimethylethyldiamine (0.15 g, 1.65 mmol) in ethanol (20 ml) was refluxed for 2 hr followed by addition of a solution of cadmium(II) acetate dihydrate (0.44 g, 1.65 mmol) and sodium thiocyanate (0.27 g, 3.3 mmol) in a minimum amount of water. The resulting solution was refluxed for 30 min, then set aside at room temperature. The crystals of the title compound were obtained in a few days.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Figures top

Fig. 1. Thermal ellipsoid plot of the title compound at the 30% probability level. Hydrogen atoms have been omitted for clarity. Symmetry code: ' = x, –y+1/2, z - 1/2.

catena-Poly[[{N,N-dimethyl-N'-[1-(pyridin-2- yl)ethylidene]ethane-1,2-diamine- κ³N,N',N''}(thiocyanato-κN)cadmium(II)]- µ-thiocyanato-κ²S:N] top

Crystal data top

[Cd(NCS)₂(C₁₁H₁₇N₃)]	F(000) = 840
M_r = 419.84	D_x = 1.623 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 9975 reflections
a = 14.602 (2) Å	θ = 2.6–31.2°
b = 9.5827 (14) Å	µ = 1.51 mm⁻¹
c = 12.8714 (19) Å	T = 100 K
β = 107.483 (2)°	Needle, colorless
V = 1717.9 (4) Å³	0.35 × 0.29 × 0.08 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	3756 independent reflections
Radiation source: fine-focus sealed tube	3298 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.047
ϕ and ω scans	θ_max = 27.0°, θ_min = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −18→18
T_min = 0.619, T_max = 0.889	k = −12→12
19975 measured reflections	l = −16→16

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)] = 0.023	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.056	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0162P)² + 1.0805P] where P = (F_o² + 2F_c²)/3
3756 reflections	(Δ/σ)_max = 0.001
193 parameters	Δρ_max = 0.54 e Å⁻³
0 restraints	Δρ_min = −0.73 e Å⁻³

Crystal data top

[Cd(NCS)₂(C₁₁H₁₇N₃)]	V = 1717.9 (4) Å³
M_r = 419.84	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.602 (2) Å	µ = 1.51 mm⁻¹
b = 9.5827 (14) Å	T = 100 K
c = 12.8714 (19) Å	0.35 × 0.29 × 0.08 mm
β = 107.483 (2)°

Data collection top

Bruker APEXII CCD diffractometer	3756 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3298 reflections with I > 2σ(I)
T_min = 0.619, T_max = 0.889	R_int = 0.047
19975 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.023	0 restraints
wR(F²) = 0.056	H-atom parameters constrained
S = 1.07	Δρ_max = 0.54 e Å⁻³
3756 reflections	Δρ_min = −0.73 e Å⁻³
193 parameters

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

	x	y	z	U_iso*/U_eq
Cd1	0.234091 (10)	0.221072 (15)	0.070761 (11)	0.01927 (6)
S1	0.37258 (4)	−0.22496 (6)	0.01149 (6)	0.03326 (14)
S2	0.23783 (5)	0.02652 (6)	0.23222 (5)	0.03374 (15)
N1	0.07134 (13)	0.27035 (18)	0.05811 (14)	0.0217 (4)
N2	0.22324 (12)	0.41643 (18)	0.17479 (13)	0.0208 (4)
N3	0.39458 (13)	0.30157 (18)	0.14777 (15)	0.0234 (4)
N4	0.26943 (14)	0.0221 (2)	−0.00030 (15)	0.0279 (4)
N5	0.20178 (16)	0.3205 (2)	−0.09914 (16)	0.0353 (5)
C1	−0.00422 (17)	0.2001 (2)	−0.00390 (18)	0.0265 (5)
H1	0.0067	0.1264	−0.0481	0.032*
C2	−0.09807 (18)	0.2296 (2)	−0.0070 (2)	0.0307 (5)
H2	−0.1502	0.1779	−0.0527	0.037*
C3	−0.11374 (16)	0.3359 (3)	0.05798 (19)	0.0298 (5)
H3	−0.1770	0.3575	0.0589	0.036*
C4	−0.03583 (16)	0.4107 (2)	0.12192 (18)	0.0271 (5)
H4	−0.0452	0.4844	0.1671	0.033*
C5	0.05605 (15)	0.3770 (2)	0.11946 (16)	0.0210 (4)
C6	0.14267 (15)	0.4573 (2)	0.18289 (16)	0.0212 (4)
C7	0.12885 (17)	0.5799 (2)	0.25002 (18)	0.0288 (5)
H7A	0.1180	0.5461	0.3172	0.043*
H7B	0.0732	0.6345	0.2082	0.043*
H7C	0.1864	0.6388	0.2683	0.043*
C8	0.31469 (16)	0.4832 (2)	0.23056 (18)	0.0255 (5)
H8A	0.3129	0.5220	0.3012	0.031*
H8B	0.3272	0.5605	0.1857	0.031*
C9	0.39357 (16)	0.3735 (2)	0.24905 (17)	0.0257 (5)
H9A	0.4566	0.4190	0.2817	0.031*
H9B	0.3846	0.3035	0.3017	0.031*
C10	0.42503 (18)	0.3962 (2)	0.0739 (2)	0.0310 (5)
H10A	0.4891	0.4329	0.1112	0.047*
H10B	0.3794	0.4736	0.0527	0.047*
H10C	0.4268	0.3447	0.0087	0.047*
C11	0.46237 (17)	0.1834 (3)	0.1762 (2)	0.0332 (5)
H11A	0.4639	0.1353	0.1096	0.050*
H11B	0.4415	0.1181	0.2232	0.050*
H11C	0.5267	0.2182	0.2148	0.050*
C12	0.31368 (15)	−0.0797 (2)	0.00673 (16)	0.0226 (4)
C13	0.21670 (16)	0.1178 (2)	0.33052 (17)	0.0260 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.02395 (9)	0.01941 (9)	0.01697 (9)	0.00128 (6)	0.01000 (6)	−0.00108 (5)
S1	0.0287 (3)	0.0286 (3)	0.0440 (4)	0.0061 (2)	0.0131 (3)	0.0010 (3)
S2	0.0595 (4)	0.0236 (3)	0.0247 (3)	0.0007 (3)	0.0226 (3)	0.0017 (2)
N1	0.0258 (9)	0.0225 (9)	0.0191 (9)	−0.0010 (7)	0.0103 (7)	0.0004 (7)
N2	0.0246 (9)	0.0216 (9)	0.0181 (8)	0.0009 (7)	0.0092 (7)	−0.0013 (7)
N3	0.0233 (9)	0.0225 (9)	0.0267 (10)	0.0032 (7)	0.0110 (8)	0.0003 (7)
N4	0.0385 (11)	0.0240 (10)	0.0254 (10)	0.0025 (8)	0.0160 (8)	−0.0052 (8)
N5	0.0485 (13)	0.0398 (12)	0.0220 (10)	0.0145 (10)	0.0175 (9)	0.0068 (9)
C1	0.0308 (12)	0.0250 (12)	0.0246 (11)	−0.0028 (9)	0.0096 (9)	−0.0011 (9)
C2	0.0286 (12)	0.0326 (13)	0.0298 (12)	−0.0068 (10)	0.0071 (10)	0.0041 (10)
C3	0.0244 (11)	0.0348 (13)	0.0327 (12)	0.0014 (10)	0.0120 (10)	0.0065 (10)
C4	0.0271 (12)	0.0297 (12)	0.0273 (11)	0.0035 (9)	0.0123 (9)	0.0021 (9)
C5	0.0262 (11)	0.0226 (10)	0.0163 (9)	0.0013 (8)	0.0094 (8)	0.0035 (8)
C6	0.0287 (11)	0.0216 (10)	0.0145 (9)	0.0033 (8)	0.0084 (8)	0.0030 (8)
C7	0.0305 (12)	0.0306 (12)	0.0253 (11)	0.0066 (10)	0.0084 (9)	−0.0062 (9)
C8	0.0270 (11)	0.0263 (11)	0.0252 (11)	−0.0034 (9)	0.0109 (9)	−0.0066 (9)
C9	0.0240 (11)	0.0285 (12)	0.0239 (11)	−0.0020 (9)	0.0061 (9)	−0.0008 (9)
C10	0.0355 (13)	0.0274 (12)	0.0374 (13)	−0.0006 (10)	0.0220 (11)	0.0000 (10)
C11	0.0263 (12)	0.0304 (12)	0.0412 (14)	0.0079 (10)	0.0078 (10)	0.0026 (11)
C12	0.0239 (11)	0.0280 (11)	0.0182 (10)	−0.0064 (9)	0.0097 (8)	−0.0032 (8)
C13	0.0318 (12)	0.0282 (11)	0.0187 (10)	−0.0093 (9)	0.0087 (9)	0.0006 (9)

Geometric parameters (Å, º) top

Cd1—N4	2.2406 (18)	C3—C4	1.387 (3)
Cd1—N5	2.3008 (19)	C3—H3	0.9500
Cd1—N2	2.3345 (17)	C4—C5	1.390 (3)
Cd1—N1	2.3801 (18)	C4—H4	0.9500
Cd1—N3	2.3820 (19)	C5—C6	1.496 (3)
Cd1—S2	2.7803 (6)	C6—C7	1.507 (3)
S1—C12	1.628 (2)	C7—H7A	0.9800
S2—C13	1.642 (2)	C7—H7B	0.9800
N1—C1	1.333 (3)	C7—H7C	0.9800
N1—C5	1.351 (3)	C8—C9	1.524 (3)
N2—C6	1.274 (3)	C8—H8A	0.9900
N2—C8	1.460 (3)	C8—H8B	0.9900
N3—C10	1.475 (3)	C9—H9A	0.9900
N3—C11	1.476 (3)	C9—H9B	0.9900
N3—C9	1.479 (3)	C10—H10A	0.9800
N4—C12	1.159 (3)	C10—H10B	0.9800
N5—C13ⁱ	1.155 (3)	C10—H10C	0.9800
C1—C2	1.388 (3)	C11—H11A	0.9800
C1—H1	0.9500	C11—H11B	0.9800
C2—C3	1.380 (3)	C11—H11C	0.9800
C2—H2	0.9500	C13—N5ⁱⁱ	1.155 (3)

N4—Cd1—N5	88.34 (7)	C3—C4—H4	120.3
N4—Cd1—N2	168.52 (7)	C5—C4—H4	120.3
N5—Cd1—N2	100.55 (7)	N1—C5—C4	121.3 (2)
N4—Cd1—N1	119.25 (7)	N1—C5—C6	116.56 (18)
N5—Cd1—N1	86.41 (7)	C4—C5—C6	122.14 (19)
N2—Cd1—N1	69.01 (6)	N2—C6—C5	116.59 (18)
N4—Cd1—N3	97.29 (7)	N2—C6—C7	124.9 (2)
N5—Cd1—N3	99.00 (7)	C5—C6—C7	118.48 (18)
N2—Cd1—N3	74.30 (6)	C6—C7—H7A	109.5
N1—Cd1—N3	143.28 (6)	C6—C7—H7B	109.5
N4—Cd1—S2	77.26 (5)	H7A—C7—H7B	109.5
N5—Cd1—S2	160.16 (6)	C6—C7—H7C	109.5
N2—Cd1—S2	95.65 (4)	H7A—C7—H7C	109.5
N1—Cd1—S2	88.81 (4)	H7B—C7—H7C	109.5
N3—Cd1—S2	96.33 (5)	N2—C8—C9	108.16 (17)
C13—S2—Cd1	104.63 (8)	N2—C8—H8A	110.1
C1—N1—C5	118.65 (19)	C9—C8—H8A	110.1
C1—N1—Cd1	124.79 (15)	N2—C8—H8B	110.1
C5—N1—Cd1	116.56 (14)	C9—C8—H8B	110.1
C6—N2—C8	123.78 (18)	H8A—C8—H8B	108.4
C6—N2—Cd1	121.13 (14)	N3—C9—C8	113.02 (18)
C8—N2—Cd1	115.06 (12)	N3—C9—H9A	109.0
C10—N3—C11	108.77 (18)	C8—C9—H9A	109.0
C10—N3—C9	111.49 (17)	N3—C9—H9B	109.0
C11—N3—C9	108.82 (18)	C8—C9—H9B	109.0
C10—N3—Cd1	112.34 (14)	H9A—C9—H9B	107.8
C11—N3—Cd1	110.94 (14)	N3—C10—H10A	109.5
C9—N3—Cd1	104.40 (12)	N3—C10—H10B	109.5
C12—N4—Cd1	151.16 (18)	H10A—C10—H10B	109.5
C13ⁱ—N5—Cd1	157.5 (2)	N3—C10—H10C	109.5
N1—C1—C2	123.1 (2)	H10A—C10—H10C	109.5
N1—C1—H1	118.4	H10B—C10—H10C	109.5
C2—C1—H1	118.4	N3—C11—H11A	109.5
C3—C2—C1	118.4 (2)	N3—C11—H11B	109.5
C3—C2—H2	120.8	H11A—C11—H11B	109.5
C1—C2—H2	120.8	N3—C11—H11C	109.5
C2—C3—C4	119.0 (2)	H11A—C11—H11C	109.5
C2—C3—H3	120.5	H11B—C11—H11C	109.5
C4—C3—H3	120.5	N4—C12—S1	177.5 (2)
C3—C4—C5	119.5 (2)	N5ⁱⁱ—C13—S2	178.5 (2)

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

Experimental details

Crystal data
Chemical formula	[Cd(NCS)₂(C₁₁H₁₇N₃)]
M_r	419.84
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	14.602 (2), 9.5827 (14), 12.8714 (19)
β (°)	107.483 (2)
V (Å³)	1717.9 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.51
Crystal size (mm)	0.35 × 0.29 × 0.08

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.619, 0.889
No. of measured, independent and observed [I > 2σ(I)] reflections	19975, 3756, 3298
R_int	0.047
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.023, 0.056, 1.07
No. of reflections	3756
No. of parameters	193
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.54, −0.73

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), X-SEED (Barbour, 2001), SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Selected bond lengths (Å) top

Cd1—N4	2.2406 (18)	Cd1—S2	2.7803 (6)
Cd1—N5	2.3008 (19)	S1—C12	1.628 (2)
Cd1—N2	2.3345 (17)	S2—C13	1.642 (2)
Cd1—N1	2.3801 (18)	N4—C12	1.159 (3)
Cd1—N3	2.3820 (19)	N5—C13ⁱ	1.155 (3)

Symmetry code: (i) x, −y+1/2, z−1/2.

Acknowledgements

The authors thank the University of Malaya for funding this study (FRGS grant No. FP004/2010B).

References

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