Dibromido{2-(morpholin-4-yl)-N-[1-(2-pyrid­yl)ethyl­idene]ethanamine-κ3N,N′,N′′}cadmium

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

doi:10.1107/S160053681100554X

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 3| March 2011| Page m347

doi:10.1107/S160053681100554X

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Dibromido{2-(morpholin-4-yl)-N-[1-(2-pyridyl)ethylidene]ethanamine-κ³N,N′,N′′}cadmium

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 9 February 2011; accepted 15 February 2011; online 19 February 2011)

The Cd^II ion in the title compound, [CdBr₂(C₁₃H₁₉N₃O)], is five-coordinated by the N,N′,N′′-tridentate Schiff base ligand and two Br atoms in a distorted square-pyramidal geometry. In the crystal, intermolecular C—H⋯O and C—H⋯Br hydrogen bonds link adjacent molecules into layers parallel to the ab plane. An intramolecular C—H⋯Br interaction is also observed.

Related literature

For the crystal structure of the analogous CdCl₂ complex, see: Ikmal Hisham et al. (2010 ). For the crystal structures of similar CdBr₂ complexes, see: Bermejo et al. (1999 , 2003 ). For a description of the geometry of complexes with five-coordinate metal atoms, see: Addison et al. (1984 ).

Experimental

Crystal data

[CdBr₂(C₁₃H₁₉N₃O)]
M_r = 505.53
Orthorhombic, P 2₁ 2₁ 2₁
a = 9.1906 (8) Å
b = 12.2604 (10) Å
c = 14.7499 (12) Å
V = 1662.0 (2) Å³
Z = 4
Mo Kα radiation
μ = 6.12 mm⁻¹
T = 100 K
0.33 × 0.27 × 0.19 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.237, T_max = 0.389
20236 measured reflections
3642 independent reflections
3445 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.021
wR(F²) = 0.041
S = 1.09
3642 reflections
182 parameters
H-atom parameters constrained
Δρ_max = 0.73 e Å⁻³
Δρ_min = −0.54 e Å⁻³
Absolute structure: Flack (1983 ), 1556 Friedel pairs
Flack parameter: 0.023 (9)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O1ⁱ	0.95	2.42	3.132 (4)	131
C7—H7B⋯Br1ⁱⁱ	0.98	2.92	3.840 (4)	157
C10—H10A⋯O1ⁱⁱⁱ	0.99	2.45	3.383 (4)	156
C11—H11B⋯Br2	0.99	2.91	3.727 (4)	141
Symmetry codes: (i) x, y+1, z; (ii) x+1, y, z; (iii) $[x+{\script{1\over 2}}, -y-{\script{1\over 2}}, -z+2]$ .

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/S160053681100554X/bg2390sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681100554X/bg2390Isup2.hkl

checkCIF report

Comment top

The title compound was obtained upon the reaction of 2-morpholino-N-[1-(2-pyridyl)ethylidene]ethanamine with Cd^II ion in the presence of potassium bromide. Similar to the structure of the analogous CdCl₂ complex (Ikmal Hisham et al., 2010), the metal center is five-coordinated by the N,N',N"-tridentate Schiff base ligand and two halogen atoms. The geometry of the complexes can be determined by using the index τ = (β-α)/60, where β is the largest angle and α is the second one around the metal center. For an ideal square-pyramid τ is 0, while it is 1 in a perfect trigonal-bipyramid (Addison et al.,1984). The τ value in the present structure is calculated to be 0.18, indicative of a distorted square-pyramidal geometry. The Cd—Br bond lengths in the complex are in agreement with the values reported in the literature (Bermejo et al., 1999; Bermejo et al., 2003). In the crystal, the adjacent molecules are connected together via C—H···O and C—H···Br hydrogen bonds, forming infinite layers parallel to the ab plane. Moreover an intramolecluar C—H···Br occurs.

Related literature top

For the crystal structure of the analogous CdCl₂ complex, see: Ikmal Hisham et al. (2010). For the crystal structures of similar CdBr₂ complexes, see: Bermejo et al. (1999, 2003) For the geometry of complexes, see: Addison et al. (1984).

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. After 2 hr a solution of cadmium(II) acetate dihydrate (0.44 g, 1.65 mmol) and potassium bromide (0.196 g, 1.65 mmol) in a minimum amount of water was added. The resulting solution was refluxed for 30 min, and then left at room temperature. The crystals of the title complex 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 50% probability level.

Dibromido{2-(morpholin-4-yl)-N-[1-(2-pyridyl)ethylidene]ethanamine- κ³N,N',N''}cadmium top

Crystal data top

[CdBr₂(C₁₃H₁₉N₃O)]	F(000) = 976
M_r = 505.53	D_x = 2.020 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 5963 reflections
a = 9.1906 (8) Å	θ = 2.6–30.7°
b = 12.2604 (10) Å	µ = 6.12 mm⁻¹
c = 14.7499 (12) Å	T = 100 K
V = 1662.0 (2) Å³	Block, colorless
Z = 4	0.33 × 0.27 × 0.19 mm

Data collection top

Bruker APEXII CCD diffractometer	3642 independent reflections
Radiation source: fine-focus sealed tube	3445 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
ϕ and ω scans	θ_max = 27.0°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −11→11
T_min = 0.237, T_max = 0.389	k = −15→15
20236 measured reflections	l = −18→18

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.021	H-atom parameters constrained
wR(F²) = 0.041	w = 1/[σ²(F_o²) + (0.006P)² + 1.6071P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max = 0.001
3642 reflections	Δρ_max = 0.73 e Å⁻³
182 parameters	Δρ_min = −0.54 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 1556 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.023 (9)

Crystal data top

[CdBr₂(C₁₃H₁₉N₃O)]	V = 1662.0 (2) Å³
M_r = 505.53	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 9.1906 (8) Å	µ = 6.12 mm⁻¹
b = 12.2604 (10) Å	T = 100 K
c = 14.7499 (12) Å	0.33 × 0.27 × 0.19 mm

Data collection top

Bruker APEXII CCD diffractometer	3642 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3445 reflections with I > 2σ(I)
T_min = 0.237, T_max = 0.389	R_int = 0.032
20236 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	H-atom parameters constrained
wR(F²) = 0.041	Δρ_max = 0.73 e Å⁻³
S = 1.09	Δρ_min = −0.54 e Å⁻³
3642 reflections	Absolute structure: Flack (1983), 1556 Friedel pairs
182 parameters	Absolute structure parameter: 0.023 (9)
0 restraints

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	0.03808 (2)	0.00442 (2)	0.919266 (13)	0.01367 (5)
Br1	−0.21463 (3)	0.00329 (4)	0.84484 (2)	0.02368 (7)
Br2	0.07480 (3)	−0.00774 (4)	1.092730 (19)	0.02169 (7)
O1	−0.0135 (3)	−0.34931 (19)	0.93888 (17)	0.0151 (6)
N1	0.0632 (3)	0.1977 (2)	0.90768 (19)	0.0163 (6)
N2	0.2634 (3)	0.0505 (2)	0.86157 (18)	0.0143 (6)
N3	0.1405 (3)	−0.1675 (2)	0.85991 (18)	0.0127 (6)
C1	−0.0399 (4)	0.2704 (3)	0.9296 (2)	0.0194 (7)
H1	−0.1334	0.2443	0.9463	0.023*
C2	−0.0157 (5)	0.3826 (3)	0.9291 (3)	0.0225 (9)
H2	−0.0908	0.4322	0.9451	0.027*
C3	0.1197 (4)	0.4192 (3)	0.9049 (3)	0.0240 (8)
H3	0.1400	0.4951	0.9051	0.029*
C4	0.2272 (4)	0.3455 (3)	0.8800 (2)	0.0209 (8)
H4	0.3206	0.3701	0.8616	0.025*
C5	0.1948 (4)	0.2342 (3)	0.8827 (2)	0.0145 (7)
C6	0.3044 (4)	0.1495 (3)	0.8549 (2)	0.0146 (7)
C7	0.4496 (4)	0.1874 (3)	0.8209 (3)	0.0253 (8)
H7A	0.4380	0.2199	0.7606	0.038*
H7B	0.5162	0.1252	0.8172	0.038*
H7C	0.4894	0.2420	0.8627	0.038*
C8	0.3532 (4)	−0.0426 (2)	0.8376 (2)	0.0164 (7)
H8A	0.4034	−0.0709	0.8922	0.020*
H8B	0.4278	−0.0207	0.7928	0.020*
C9	0.2553 (4)	−0.1303 (3)	0.7977 (2)	0.0176 (7)
H9A	0.2093	−0.1016	0.7419	0.021*
H9B	0.3160	−0.1937	0.7802	0.021*
C10	0.2041 (4)	−0.2361 (3)	0.9323 (2)	0.0167 (7)
H10A	0.2692	−0.1912	0.9705	0.020*
H10B	0.2630	−0.2950	0.9047	0.020*
C11	0.0853 (4)	−0.2858 (3)	0.9907 (2)	0.0181 (7)
H11A	0.1303	−0.3323	1.0378	0.022*
H11B	0.0313	−0.2267	1.0217	0.022*
C12	−0.0787 (4)	−0.2837 (3)	0.8695 (2)	0.0177 (7)
H12A	−0.1356	−0.2242	0.8978	0.021*
H12B	−0.1463	−0.3290	0.8333	0.021*
C13	0.0361 (4)	−0.2354 (3)	0.8079 (2)	0.0174 (7)
H13A	0.0894	−0.2950	0.7770	0.021*
H13B	−0.0114	−0.1901	0.7609	0.021*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.01446 (9)	0.01227 (9)	0.01429 (9)	0.00005 (13)	0.00293 (7)	0.00048 (13)
Br1	0.01711 (14)	0.02244 (15)	0.03150 (16)	0.0017 (2)	−0.00424 (12)	0.0024 (2)
Br2	0.02749 (16)	0.02287 (17)	0.01472 (13)	0.00513 (19)	−0.00019 (11)	−0.00188 (19)
O1	0.0147 (14)	0.0118 (11)	0.0190 (14)	−0.0018 (10)	−0.0005 (10)	0.0025 (10)
N1	0.0184 (15)	0.0152 (13)	0.0154 (14)	0.0012 (11)	0.0020 (12)	0.0039 (11)
N2	0.0147 (15)	0.0163 (13)	0.0120 (13)	0.0018 (11)	0.0003 (11)	0.0003 (11)
N3	0.0155 (14)	0.0100 (13)	0.0128 (14)	−0.0002 (11)	0.0015 (11)	0.0010 (11)
C1	0.0217 (18)	0.0191 (16)	0.0173 (18)	0.0019 (15)	0.0056 (15)	0.0012 (14)
C2	0.032 (2)	0.0147 (16)	0.021 (2)	0.0080 (16)	−0.0011 (17)	0.0001 (15)
C3	0.034 (2)	0.0116 (15)	0.027 (2)	−0.0018 (14)	−0.0087 (17)	−0.0008 (15)
C4	0.0203 (18)	0.0163 (17)	0.0260 (19)	−0.0043 (14)	−0.0043 (15)	0.0000 (14)
C5	0.0152 (18)	0.0154 (16)	0.0128 (17)	0.0028 (13)	−0.0030 (15)	0.0017 (14)
C6	0.0145 (17)	0.0176 (16)	0.0116 (16)	−0.0009 (13)	−0.0011 (13)	0.0041 (13)
C7	0.0204 (19)	0.0187 (17)	0.037 (2)	−0.0055 (15)	0.0066 (17)	0.0005 (15)
C8	0.0134 (17)	0.0135 (15)	0.0224 (18)	0.0018 (12)	0.0040 (14)	0.0031 (13)
C9	0.0202 (18)	0.0164 (17)	0.0162 (17)	0.0017 (13)	0.0064 (14)	−0.0013 (14)
C10	0.0169 (17)	0.0155 (16)	0.0178 (18)	0.0023 (13)	−0.0007 (15)	0.0045 (14)
C11	0.0149 (17)	0.0172 (17)	0.0223 (18)	−0.0020 (13)	−0.0011 (14)	0.0052 (14)
C12	0.0183 (18)	0.0150 (16)	0.0198 (18)	−0.0016 (13)	−0.0013 (15)	−0.0005 (13)
C13	0.0210 (18)	0.0165 (16)	0.0147 (16)	0.0011 (14)	−0.0007 (14)	−0.0049 (13)

Geometric parameters (Å, º) top

Cd1—N2	2.309 (3)	C4—H4	0.9500
Cd1—N1	2.388 (3)	C5—C6	1.504 (5)
Cd1—N3	2.469 (3)	C6—C7	1.500 (5)
Cd1—Br1	2.5690 (4)	C7—H7A	0.9800
Cd1—Br2	2.5851 (4)	C7—H7B	0.9800
O1—C11	1.420 (4)	C7—H7C	0.9800
O1—C12	1.433 (4)	C8—C9	1.520 (5)
N1—C1	1.340 (4)	C8—H8A	0.9900
N1—C5	1.341 (4)	C8—H8B	0.9900
N2—C6	1.275 (4)	C9—H9A	0.9900
N2—C8	1.452 (4)	C9—H9B	0.9900
N3—C9	1.471 (4)	C10—C11	1.518 (5)
N3—C10	1.479 (4)	C10—H10A	0.9900
N3—C13	1.484 (4)	C10—H10B	0.9900
C1—C2	1.393 (5)	C11—H11A	0.9900
C1—H1	0.9500	C11—H11B	0.9900
C2—C3	1.370 (6)	C12—C13	1.514 (5)
C2—H2	0.9500	C12—H12A	0.9900
C3—C4	1.388 (5)	C12—H12B	0.9900
C3—H3	0.9500	C13—H13A	0.9900
C4—C5	1.397 (5)	C13—H13B	0.9900

N2—Cd1—N1	69.15 (9)	C6—C7—H7B	109.5
N2—Cd1—N3	74.71 (9)	H7A—C7—H7B	109.5
N1—Cd1—N3	141.76 (9)	C6—C7—H7C	109.5
N2—Cd1—Br1	130.89 (7)	H7A—C7—H7C	109.5
N1—Cd1—Br1	93.56 (7)	H7B—C7—H7C	109.5
N3—Cd1—Br1	100.87 (6)	N2—C8—C9	108.3 (3)
N2—Cd1—Br2	105.18 (7)	N2—C8—H8A	110.0
N1—Cd1—Br2	96.63 (7)	C9—C8—H8A	110.0
N3—Cd1—Br2	104.59 (6)	N2—C8—H8B	110.0
Br1—Cd1—Br2	122.729 (12)	C9—C8—H8B	110.0
C11—O1—C12	110.1 (2)	H8A—C8—H8B	108.4
C1—N1—C5	118.8 (3)	N3—C9—C8	113.7 (3)
C1—N1—Cd1	125.1 (2)	N3—C9—H9A	108.8
C5—N1—Cd1	116.0 (2)	C8—C9—H9A	108.8
C6—N2—C8	124.2 (3)	N3—C9—H9B	108.8
C6—N2—Cd1	121.8 (2)	C8—C9—H9B	108.8
C8—N2—Cd1	114.02 (19)	H9A—C9—H9B	107.7
C9—N3—C10	110.1 (3)	N3—C10—C11	110.7 (3)
C9—N3—C13	108.4 (3)	N3—C10—H10A	109.5
C10—N3—C13	108.1 (2)	C11—C10—H10A	109.5
C9—N3—Cd1	103.29 (18)	N3—C10—H10B	109.5
C10—N3—Cd1	112.3 (2)	C11—C10—H10B	109.5
C13—N3—Cd1	114.57 (19)	H10A—C10—H10B	108.1
N1—C1—C2	122.8 (3)	O1—C11—C10	112.0 (3)
N1—C1—H1	118.6	O1—C11—H11A	109.2
C2—C1—H1	118.6	C10—C11—H11A	109.2
C3—C2—C1	118.0 (4)	O1—C11—H11B	109.2
C3—C2—H2	121.0	C10—C11—H11B	109.2
C1—C2—H2	121.0	H11A—C11—H11B	107.9
C2—C3—C4	120.1 (3)	O1—C12—C13	110.9 (3)
C2—C3—H3	119.9	O1—C12—H12A	109.5
C4—C3—H3	119.9	C13—C12—H12A	109.5
C3—C4—C5	118.4 (3)	O1—C12—H12B	109.5
C3—C4—H4	120.8	C13—C12—H12B	109.5
C5—C4—H4	120.8	H12A—C12—H12B	108.0
N1—C5—C4	121.7 (3)	N3—C13—C12	111.1 (3)
N1—C5—C6	116.6 (3)	N3—C13—H13A	109.4
C4—C5—C6	121.6 (3)	C12—C13—H13A	109.4
N2—C6—C7	125.7 (3)	N3—C13—H13B	109.4
N2—C6—C5	116.0 (3)	C12—C13—H13B	109.4
C7—C6—C5	118.2 (3)	H13A—C13—H13B	108.0
C6—C7—H7A	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O1ⁱ	0.95	2.42	3.132 (4)	131
C7—H7B···Br1ⁱⁱ	0.98	2.92	3.840 (4)	157
C10—H10A···O1ⁱⁱⁱ	0.99	2.45	3.383 (4)	156
C11—H11B···Br2	0.99	2.91	3.727 (4)	141

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

Experimental details

Crystal data
Chemical formula	[CdBr₂(C₁₃H₁₉N₃O)]
M_r	505.53
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	100
a, b, c (Å)	9.1906 (8), 12.2604 (10), 14.7499 (12)
V (Å³)	1662.0 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	6.12
Crystal size (mm)	0.33 × 0.27 × 0.19

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.237, 0.389
No. of measured, independent and observed [I > 2σ(I)] reflections	20236, 3642, 3445
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.041, 1.09
No. of reflections	3642
No. of parameters	182
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.73, −0.54
Absolute structure	Flack (1983), 1556 Friedel pairs
Absolute structure parameter	0.023 (9)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O1ⁱ	0.95	2.42	3.132 (4)	131
C7—H7B···Br1ⁱⁱ	0.98	2.92	3.840 (4)	157
C10—H10A···O1ⁱⁱⁱ	0.99	2.45	3.383 (4)	156
C11—H11B···Br2	0.99	2.91	3.727 (4)	141

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

Acknowledgements

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

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