Di-μ-thio­cyanato-κ2N:S;κ2S:N-bis­({2-morpholino-N-[1-(2-pyrid­yl)ethyl­idene]ethanamine-κ3N,N′,N′′}(thio­cyanato-κN)cadmium)

Suleiman Gwaram, N.; Ikmal Hisham, N.A.; Khaledi, H.; Mohd Ali, H.

doi:10.1107/S1600536811002480

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 2| February 2011| Page m251

doi:10.1107/S1600536811002480

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Di-μ-thiocyanato-κ²N:S;κ²S:N-bis({2-morpholino-N-[1-(2-pyridyl)ethylidene]ethanamine-κ³N,N′,N′′}(thiocyanato-κN)cadmium)

Nura Suleiman Gwaram,^a Nurul Azimah Ikmal Hisham,^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 14 January 2011; accepted 18 January 2011; online 22 January 2011)

In the title complex, [Cd₂(NCS)₄(C₁₃H₁₉N₃O)₂], the two Cd^II ions are bridged by a pair of thiocyanate N:S-bridging ligands around an inversion center. One terminal thiocyanate N atom and one N,N′,N′′-tridentate Schiff base ligand complete a distorted CdN₅S octahedral geometry about each Cd^II atom. In the crystal, the Schiff base aromatic rings of adjacent molecules are arranged above each other into infinite chains along the a axis with alternate centroid–centroid separations of 3.5299 (13) and 3.7857 (13) Å.

Related literature

For the structure of the Cu(II) complex with the same Schiff base and thiocyanate, see: Suleiman Gwaram et al. (2011 ). For the structures of similar cadmium complexes, see: Banerjee et al. (2005 ); You et al. (2006 ).

Experimental

Crystal data

[Cd₂(NCS)₄(C₁₃H₁₉N₃O)₂]
M_r = 923.74
Monoclinic, P 2₁ /c
a = 7.2934 (2) Å
b = 26.4035 (5) Å
c = 10.0111 (3) Å
β = 107.853 (3)°
V = 1835.02 (9) Å³
Z = 2
Mo Kα radiation
μ = 1.43 mm⁻¹
T = 100 K
0.38 × 0.23 × 0.07 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.613, T_max = 0.907
15344 measured reflections
4008 independent reflections
3638 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.023
wR(F²) = 0.047
S = 1.10
4008 reflections
218 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.39 e Å⁻³
Δρ_min = −0.45 e Å⁻³

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/S1600536811002480/om2400sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811002480/om2400Isup2.hkl

checkCIF report

Comment top

The title compound is a mixed-ligand cadmium(II) complex with thiocyanate and the Schiff base 2-morpholino-N-[1-(2-pyridyl)ethylidene]ethanamine. Unlike the mononuclear square-pyramidal structure of the analogous copper(II) complex (Suleiman Gwaram et al., 2011), the present structure represents a dinuclear metal complex with a distorted octahedral geometry around the cadmium atoms. Each two Cd^II centers are linked by a pair of thiocyanate N:S bridges around an inversion center to form an eight-membered Cd₂(µ₂-NCS)₂ ring. The resulting ring has a chair conformation, the displacement of Cd1 out of the (NCS)₂ plane being 0.635 (2) Å. Within this double bridged dimer, the Cd···Cd distance [5.9380 (3) Å] is similar to those observed in the related complexes (Banerjee et al., 2005; You et al., 2006). The distorted octahedral geometry about the metal cadmium is completed by one terminal thiocyanate N atom and one N,N',N"-tridentate Schiff base ligand. In the crystal, the molecules are connected into infinite chains along the a axis via π-π interactions formed by the Schiff base aromatic ring and its symmetry related counterparts at (-x + 1, -y, -z and –x + 2, -y, -z) with centroid separations of 3.5299 (13) Å and 3.7857 (13) Å respectively.

Related literature top

For the structure of the Cu(II) complex with the same Schiff base and thiocyanate, see: Suleiman Gwaram et al. (2011). For the structures of similar cadmium complexes, see: Banerjee et al. (2005); You et al. (2006).

Experimental top

A mixture of 2-acetylpyridine (0.20 g, 1.65 mmol) and 4-(2-aminoethyl)morpholine (0.21 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 (0.268 g, 3.30 mmol) in a minimum amount of water. The resulting solution was refluxed for 30 min, then left at room temperature. The crystals of the title complex were obtained in a week.

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 50% probability level. Hydrogen atoms have been omitted for clarity. The unlabelled atoms are generated by the symmetry operation (–x + 2, –y, –z + 1).

Di-µ-thiocyanato-κ²N:S;κ²S:N- bis({2-morpholino-N-[1-(2-pyridyl)ethylidene]ethanamine- κ³N,N',N''}(thiocyanato-κN)cadmium) top

Crystal data top

[Cd₂(NCS)₄(C₁₃H₁₉N₃O)₂]	F(000) = 928
M_r = 923.74	D_x = 1.672 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7745 reflections
a = 7.2934 (2) Å	θ = 2.3–30.5°
b = 26.4035 (5) Å	µ = 1.43 mm⁻¹
c = 10.0111 (3) Å	T = 100 K
β = 107.853 (3)°	Plate, colourless
V = 1835.02 (9) Å³	0.38 × 0.23 × 0.07 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	4008 independent reflections
Radiation source: fine-focus sealed tube	3638 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.026
ϕ and ω scans	θ_max = 27.0°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→9
T_min = 0.613, T_max = 0.907	k = −33→33
15344 measured reflections	l = −12→12

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) = 0.047	H-atom parameters constrained
S = 1.10	w = 1/[σ²(F_o²) + (0.0141P)² + 1.4854P] where P = (F_o² + 2F_c²)/3
4008 reflections	(Δ/σ)_max = 0.001
218 parameters	Δρ_max = 0.39 e Å⁻³
2 restraints	Δρ_min = −0.45 e Å⁻³

Crystal data top

[Cd₂(NCS)₄(C₁₃H₁₉N₃O)₂]	V = 1835.02 (9) Å³
M_r = 923.74	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.2934 (2) Å	µ = 1.43 mm⁻¹
b = 26.4035 (5) Å	T = 100 K
c = 10.0111 (3) Å	0.38 × 0.23 × 0.07 mm
β = 107.853 (3)°

Data collection top

Bruker APEXII CCD diffractometer	4008 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3638 reflections with I > 2σ(I)
T_min = 0.613, T_max = 0.907	R_int = 0.026
15344 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.023	2 restraints
wR(F²) = 0.047	H-atom parameters constrained
S = 1.10	Δρ_max = 0.39 e Å⁻³
4008 reflections	Δρ_min = −0.45 e Å⁻³
218 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	0.88459 (2)	0.089861 (5)	0.314896 (15)	0.01292 (5)
S1	0.67607 (7)	0.05268 (2)	0.46956 (6)	0.01758 (11)
S2	0.45365 (9)	0.20002 (2)	−0.00994 (6)	0.02685 (13)
O1	1.0113 (3)	0.19368 (6)	0.65208 (18)	0.0309 (4)
N1	0.7974 (2)	0.02944 (6)	0.12874 (18)	0.0153 (4)
N2	0.9534 (2)	0.11963 (7)	0.11679 (18)	0.0166 (4)
N3	1.0711 (3)	0.16656 (7)	0.38989 (19)	0.0166 (4)
N4	0.6008 (3)	0.13692 (7)	0.2228 (2)	0.0214 (4)
N5	1.1395 (3)	0.03924 (7)	0.42969 (19)	0.0194 (4)
C1	0.7455 (3)	−0.01826 (8)	0.1403 (2)	0.0181 (4)
H1	0.7435	−0.0300	0.2296	0.022*
C2	0.6942 (3)	−0.05172 (9)	0.0281 (2)	0.0217 (5)
H2	0.6593	−0.0857	0.0402	0.026*
C3	0.6952 (3)	−0.03430 (9)	−0.1020 (2)	0.0226 (5)
H3	0.6596	−0.0561	−0.1812	0.027*
C4	0.7486 (3)	0.01527 (9)	−0.1153 (2)	0.0203 (5)
H4	0.7495	0.0279	−0.2040	0.024*
C5	0.8011 (3)	0.04641 (8)	0.0022 (2)	0.0163 (4)
C6	0.8705 (3)	0.09967 (8)	−0.0016 (2)	0.0183 (4)
C7	0.8396 (4)	0.12483 (10)	−0.1409 (2)	0.0303 (6)
H7A	0.9115	0.1567	−0.1277	0.045*
H7B	0.7020	0.1317	−0.1840	0.045*
H7C	0.8849	0.1025	−0.2023	0.045*
C8	1.0294 (3)	0.17102 (8)	0.1330 (2)	0.0212 (5)
H8A	0.9225	0.1957	0.1163	0.025*
H8B	1.0991	0.1775	0.0640	0.025*
C9	1.1654 (3)	0.17704 (8)	0.2811 (2)	0.0203 (5)
H9A	1.2757	0.1537	0.2943	0.024*
H9B	1.2165	0.2120	0.2932	0.024*
C10	1.2234 (3)	0.16048 (9)	0.5272 (2)	0.0228 (5)
H10A	1.3057	0.1911	0.5475	0.027*
H10B	1.3056	0.1311	0.5230	0.027*
C11	1.1333 (4)	0.15259 (9)	0.6422 (2)	0.0285 (5)
H11A	1.0571	0.1209	0.6241	0.034*
H11B	1.2364	0.1488	0.7328	0.034*
C12	0.8634 (4)	0.19928 (9)	0.5217 (3)	0.0266 (5)
H12A	0.7776	0.2276	0.5287	0.032*
H12B	0.7852	0.1680	0.5009	0.032*
C13	0.9472 (3)	0.20975 (8)	0.4035 (2)	0.0207 (5)
H13A	0.8418	0.2144	0.3145	0.025*
H13B	1.0243	0.2413	0.4233	0.025*
C14	0.5395 (3)	0.16332 (8)	0.1265 (2)	0.0164 (4)
C15	0.7869 (3)	−0.00104 (8)	0.5288 (2)	0.0142 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.01395 (7)	0.01189 (8)	0.01358 (8)	0.00068 (6)	0.00518 (5)	0.00135 (6)
S1	0.0165 (2)	0.0166 (3)	0.0221 (3)	0.0035 (2)	0.0095 (2)	0.0053 (2)
S2	0.0255 (3)	0.0263 (3)	0.0251 (3)	0.0015 (2)	0.0024 (2)	0.0085 (2)
O1	0.0435 (11)	0.0281 (9)	0.0257 (9)	−0.0086 (8)	0.0172 (8)	−0.0098 (7)
N1	0.0132 (8)	0.0162 (9)	0.0167 (9)	0.0012 (7)	0.0048 (7)	−0.0004 (7)
N2	0.0159 (9)	0.0168 (9)	0.0191 (9)	0.0013 (7)	0.0085 (7)	0.0014 (7)
N3	0.0178 (9)	0.0150 (9)	0.0192 (9)	−0.0010 (7)	0.0088 (7)	−0.0012 (7)
N4	0.0170 (9)	0.0219 (10)	0.0260 (10)	0.0029 (8)	0.0074 (8)	0.0023 (8)
N5	0.0156 (9)	0.0207 (10)	0.0229 (10)	−0.0002 (8)	0.0072 (8)	0.0036 (8)
C1	0.0144 (10)	0.0195 (11)	0.0204 (11)	0.0000 (8)	0.0054 (9)	0.0001 (9)
C2	0.0157 (10)	0.0200 (12)	0.0277 (12)	0.0003 (9)	0.0044 (9)	−0.0036 (9)
C3	0.0156 (10)	0.0259 (12)	0.0231 (12)	0.0032 (9)	0.0014 (9)	−0.0089 (9)
C4	0.0168 (10)	0.0269 (12)	0.0165 (11)	0.0041 (9)	0.0044 (9)	−0.0009 (9)
C5	0.0127 (9)	0.0198 (11)	0.0169 (10)	0.0034 (8)	0.0053 (8)	−0.0003 (8)
C6	0.0196 (10)	0.0200 (12)	0.0182 (11)	0.0057 (9)	0.0102 (9)	0.0027 (8)
C7	0.0436 (15)	0.0288 (13)	0.0213 (12)	0.0030 (11)	0.0140 (11)	0.0061 (10)
C8	0.0271 (12)	0.0170 (11)	0.0243 (12)	−0.0023 (9)	0.0150 (10)	0.0032 (9)
C9	0.0198 (11)	0.0184 (11)	0.0268 (12)	−0.0040 (9)	0.0133 (10)	−0.0006 (9)
C10	0.0233 (11)	0.0201 (12)	0.0222 (12)	−0.0053 (9)	0.0030 (9)	−0.0018 (9)
C11	0.0356 (14)	0.0290 (13)	0.0191 (12)	−0.0071 (11)	0.0054 (10)	−0.0028 (10)
C12	0.0320 (13)	0.0189 (12)	0.0359 (14)	−0.0058 (10)	0.0207 (11)	−0.0097 (10)
C13	0.0252 (12)	0.0117 (10)	0.0279 (12)	−0.0011 (9)	0.0122 (10)	−0.0026 (9)
C14	0.0122 (9)	0.0157 (10)	0.0214 (10)	0.0007 (8)	0.0053 (8)	−0.0012 (7)
C15	0.0115 (9)	0.0174 (9)	0.0150 (10)	−0.0011 (7)	0.0060 (8)	0.0015 (8)

Geometric parameters (Å, º) top

Cd1—N5	2.2922 (18)	C3—H3	0.9500
Cd1—N2	2.3267 (17)	C4—C5	1.389 (3)
Cd1—N4	2.3469 (18)	C4—H4	0.9500
Cd1—N1	2.3866 (17)	C5—C6	1.499 (3)
Cd1—N3	2.4269 (17)	C6—C7	1.498 (3)
Cd1—S1	2.6679 (5)	C7—H7A	0.9800
S1—C15	1.650 (2)	C7—H7B	0.9800
S2—C14	1.635 (2)	C7—H7C	0.9800
O1—C12	1.423 (3)	C8—C9	1.518 (3)
O1—C11	1.426 (3)	C8—H8A	0.9900
N1—C1	1.330 (3)	C8—H8B	0.9900
N1—C5	1.352 (3)	C9—H9A	0.9900
N2—C6	1.268 (3)	C9—H9B	0.9900
N2—C8	1.456 (3)	C10—C11	1.505 (3)
N3—C9	1.482 (3)	C10—H10A	0.9900
N3—C10	1.487 (3)	C10—H10B	0.9900
N3—C13	1.487 (3)	C11—H11A	0.9900
N4—C14	1.162 (3)	C11—H11B	0.9900
N5—C15ⁱ	1.158 (3)	C12—C13	1.514 (3)
C1—C2	1.388 (3)	C12—H12A	0.9900
C1—H1	0.9500	C12—H12B	0.9900
C2—C3	1.383 (3)	C13—H13A	0.9900
C2—H2	0.9500	C13—H13B	0.9900
C3—C4	1.384 (3)	C15—N5ⁱ	1.158 (3)

N5—Cd1—N2	105.70 (6)	N2—C6—C5	115.71 (19)
N5—Cd1—N4	171.05 (6)	C7—C6—C5	118.9 (2)
N2—Cd1—N4	83.16 (6)	C6—C7—H7A	109.5
N5—Cd1—N1	89.01 (6)	C6—C7—H7B	109.5
N2—Cd1—N1	68.63 (6)	H7A—C7—H7B	109.5
N4—Cd1—N1	93.18 (6)	C6—C7—H7C	109.5
N5—Cd1—N3	92.28 (6)	H7A—C7—H7C	109.5
N2—Cd1—N3	74.62 (6)	H7B—C7—H7C	109.5
N4—Cd1—N3	91.32 (6)	N2—C8—C9	108.61 (18)
N1—Cd1—N3	142.12 (6)	N2—C8—H8A	110.0
N5—Cd1—S1	90.78 (5)	C9—C8—H8A	110.0
N2—Cd1—S1	158.33 (4)	N2—C8—H8B	110.0
N4—Cd1—S1	80.32 (5)	C9—C8—H8B	110.0
N1—Cd1—S1	98.30 (4)	H8A—C8—H8B	108.3
N3—Cd1—S1	119.52 (4)	N3—C9—C8	112.74 (18)
C15—S1—Cd1	102.77 (7)	N3—C9—H9A	109.0
C12—O1—C11	109.23 (17)	C8—C9—H9A	109.0
C1—N1—C5	118.92 (18)	N3—C9—H9B	109.0
C1—N1—Cd1	125.41 (14)	C8—C9—H9B	109.0
C5—N1—Cd1	115.67 (13)	H9A—C9—H9B	107.8
C6—N2—C8	123.20 (19)	N3—C10—C11	110.18 (19)
C6—N2—Cd1	119.39 (14)	N3—C10—H10A	109.6
C8—N2—Cd1	113.20 (13)	C11—C10—H10A	109.6
C9—N3—C10	108.44 (17)	N3—C10—H10B	109.6
C9—N3—C13	110.88 (17)	C11—C10—H10B	109.6
C10—N3—C13	107.49 (17)	H10A—C10—H10B	108.1
C9—N3—Cd1	105.72 (12)	O1—C11—C10	112.1 (2)
C10—N3—Cd1	112.63 (13)	O1—C11—H11A	109.2
C13—N3—Cd1	111.67 (13)	C10—C11—H11A	109.2
C14—N4—Cd1	135.42 (16)	O1—C11—H11B	109.2
C15ⁱ—N5—Cd1	154.57 (17)	C10—C11—H11B	109.2
N1—C1—C2	123.1 (2)	H11A—C11—H11B	107.9
N1—C1—H1	118.5	O1—C12—C13	111.19 (19)
C2—C1—H1	118.5	O1—C12—H12A	109.4
C3—C2—C1	118.2 (2)	C13—C12—H12A	109.4
C3—C2—H2	120.9	O1—C12—H12B	109.4
C1—C2—H2	120.9	C13—C12—H12B	109.4
C2—C3—C4	119.2 (2)	H12A—C12—H12B	108.0
C2—C3—H3	120.4	N3—C13—C12	109.51 (18)
C4—C3—H3	120.4	N3—C13—H13A	109.8
C3—C4—C5	119.4 (2)	C12—C13—H13A	109.8
C3—C4—H4	120.3	N3—C13—H13B	109.8
C5—C4—H4	120.3	C12—C13—H13B	109.8
N1—C5—C4	121.2 (2)	H13A—C13—H13B	108.2
N1—C5—C6	116.03 (18)	N4—C14—S2	179.4 (2)
C4—C5—C6	122.76 (19)	N5ⁱ—C15—S1	178.34 (19)
N2—C6—C7	125.3 (2)

Symmetry code: (i) −x+2, −y, −z+1.

Experimental details

Crystal data
Chemical formula	[Cd₂(NCS)₄(C₁₃H₁₉N₃O)₂]
M_r	923.74
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	7.2934 (2), 26.4035 (5), 10.0111 (3)
β (°)	107.853 (3)
V (Å³)	1835.02 (9)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.43
Crystal size (mm)	0.38 × 0.23 × 0.07

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.613, 0.907
No. of measured, independent and observed [I > 2σ(I)] reflections	15344, 4008, 3638
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.023, 0.047, 1.10
No. of reflections	4008
No. of parameters	218
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.39, −0.45

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

Acknowledgements

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

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