Bis{4-chloro-2-[2-(1H-indol-3-yl)ethyl­imino­meth­yl]phenolato-κ2N,O}zinc(II)

Ali, H.M.; Mohamed Mustafa, M.I.; Rizal, M.R.; Ng, S.W.

doi:10.1107/S1600536808002213

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 2| February 2008| Page m421

doi:10.1107/S1600536808002213

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Bis{4-chloro-2-[2-(1H-indol-3-yl)ethyliminomethyl]phenolato-κ²N,O}zinc(II)

Hapipah M. Ali,^a M. I Mohamed Mustafa,^a Mohd. Razali Rizal ^a and Seik Weng Ng ^a ^*

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

(Received 7 January 2008; accepted 21 January 2008; online 25 January 2008)

The Zn atom in the title compound, [Zn(C₁₇H₁₄ClN₂O)₂], is N,O-chelated by two deprotonated Schiff base monoanionic ligands in a tetrahedral coordination geometry. The Zn atom lies on a special position of site symmetry 2.

Related literature

For the structure of the unsubstituted [(C₁₇H₁₅N₂O)₂Zn], see Chen et al. (2007 ); Ng (2008 ).

Experimental

Crystal data

[Zn(C₁₇H₁₄ClN₂O)₂]
M_r = 660.87
Monoclinic, C 2/c
a = 25.8989 (3) Å
b = 5.4960 (1) Å
c = 20.6138 (3) Å
β = 91.801 (1)°
V = 2932.73 (8) Å³
Z = 4
Mo Kα radiation
μ = 1.06 mm⁻¹
T = 128 (2) K
0.50 × 0.30 × 0.17 mm

Data collection

Bruker APEXII diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.714, T_max = 0.840
17664 measured reflections
3352 independent reflections
3023 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.025
wR(F²) = 0.100
S = 1.21
3352 reflections
251 parameters
14 restraints
All H-atom parameters refined
Δρ_max = 0.55 e Å⁻³
Δρ_min = −0.56 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Zn1—O1	1.907 (1)
Zn1—N1	2.016 (1)

O1—Zn1—O1ⁱ	116.62 (8)
O1—Zn1—N1	95.57 (5)
O1—Zn1—N1ⁱ	125.55 (6)
N1—Zn1—N1ⁱ	99.56 (8)
Symmetry code: (i) $[-x+1, y, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2005 ); cell refinement: SAINT (Bruker, 2005); 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: publCIF (Westrip, 2008 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808002213/hg2370sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808002213/hg2370Isup2.hkl

checkCIF report

Comment top

We have recently reported the low-temperature structure of the zinc derivative of the ligand without any substituent, [C₁₇H₁₅N₂O)₂Zn] (Ng, 2008); the low-temperature structure is identical to the room-temperature structure (Chen et al., 2007). The present compound has a chlorine substituent but this does not lead to significant changes to the bond dimensions of the central metal.

Related literature top

For the structure of the unsubstituted [(C₁₇H₁₅N₂O)₂Zn], see Chen et al. (2007); Ng (2008).

Experimental top

The Schiff base ligand was synthesized by the reaction of tryptamine (0.32 g, 2 mmol), 5-chlorosalicylaldehyde (0.24 g, 2 mmol) and zinc acetate (0.19 g, 1 mmol) in ethanol. There organic reagents were first heated for an hour. Zinc acetate was then added followed by excess of triethylamine (1 ml). Crystals were obtained by recrystallization from dimethylformamide.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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: publCIF (Westrip, 2008).

Figures top

Fig. 1. Thermal ellipsoid plot of Zn(C₁₇H₁₄ClN₂O). Displacement ellipsoids are drawn at the 50% probability level, and H atoms are shown as spheres of arbitrary radii.

Bis{4-chloro-2-[2-(1H-indol-3-yl)ethyliminomethyl]phenolato- κ²N,O}zinc(II) top

Crystal data top

[Zn(C₁₇H₁₄ClN₂O)₂]	F(000) = 1360
M_r = 660.87	D_x = 1.497 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 9956 reflections
a = 25.8989 (3) Å	θ = 2.5–31.2°
b = 5.4960 (1) Å	µ = 1.06 mm⁻¹
c = 20.6138 (3) Å	T = 128 K
β = 91.801 (1)°	Block, colorless
V = 2932.73 (8) Å³	0.50 × 0.30 × 0.17 mm
Z = 4

Data collection top

Bruker APEXII diffractometer	3352 independent reflections
Radiation source: medium-focus sealed tube	3023 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
ϕ and ω scans	θ_max = 27.5°, θ_min = 1.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −33→33
T_min = 0.714, T_max = 0.840	k = −6→7
17664 measured reflections	l = −26→26

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)] = 0.025	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.100	All H-atom parameters refined
S = 1.21	w = 1/[σ²(F_o²) + (0.0632P)² + 1.1156P] where P = (F_o² + 2F_c²)/3
3352 reflections	(Δ/σ)_max = 0.001
251 parameters	Δρ_max = 0.55 e Å⁻³
14 restraints	Δρ_min = −0.56 e Å⁻³

Crystal data top

[Zn(C₁₇H₁₄ClN₂O)₂]	V = 2932.73 (8) Å³
M_r = 660.87	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 25.8989 (3) Å	µ = 1.06 mm⁻¹
b = 5.4960 (1) Å	T = 128 K
c = 20.6138 (3) Å	0.50 × 0.30 × 0.17 mm
β = 91.801 (1)°

Data collection top

Bruker APEXII diffractometer	3352 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3023 reflections with I > 2σ(I)
T_min = 0.714, T_max = 0.840	R_int = 0.025
17664 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.025	14 restraints
wR(F²) = 0.100	All H-atom parameters refined
S = 1.21	Δρ_max = 0.55 e Å⁻³
3352 reflections	Δρ_min = −0.56 e Å⁻³
251 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Zn1	0.5000	0.49480 (5)	0.7500	0.01823 (11)
Cl1	0.39490 (2)	0.33657 (10)	0.42675 (2)	0.03469 (14)
O1	0.46240 (5)	0.6771 (2)	0.68555 (6)	0.0256 (3)
N1	0.53085 (5)	0.2579 (3)	0.68736 (6)	0.0167 (3)
C1	0.45075 (6)	0.5975 (3)	0.62688 (7)	0.0175 (3)
N2	0.71557 (6)	−0.2875 (3)	0.76815 (7)	0.0235 (3)
C2	0.41428 (7)	0.7308 (3)	0.58836 (8)	0.0226 (3)
C3	0.39787 (7)	0.6548 (3)	0.52766 (8)	0.0230 (3)
C4	0.41765 (7)	0.4409 (4)	0.50234 (8)	0.0216 (3)
C5	0.45433 (7)	0.3096 (3)	0.53648 (8)	0.0206 (3)
C6	0.47188 (6)	0.3836 (3)	0.59882 (7)	0.0167 (3)
C7	0.51092 (6)	0.2301 (3)	0.63013 (8)	0.0181 (3)
C8	0.56967 (6)	0.0809 (3)	0.71064 (8)	0.0186 (3)
C9	0.62386 (7)	0.1885 (4)	0.70984 (11)	0.0305 (4)
C10	0.66211 (7)	0.0247 (3)	0.74448 (10)	0.0233 (4)
C11	0.68435 (7)	−0.1805 (3)	0.72056 (9)	0.0245 (4)
C12	0.68028 (6)	0.0477 (3)	0.81090 (9)	0.0209 (3)
C13	0.67219 (7)	0.2182 (4)	0.86012 (10)	0.0296 (4)
C15	0.69689 (9)	0.1852 (4)	0.91969 (10)	0.0359 (5)
C16	0.72995 (9)	−0.0135 (4)	0.93160 (11)	0.0344 (5)
C17	0.73904 (7)	−0.1845 (4)	0.88415 (9)	0.0279 (4)
C18	0.71359 (6)	−0.1517 (3)	0.82397 (8)	0.0205 (3)
H2N	0.7331 (9)	−0.421 (3)	0.7639 (13)	0.042 (7)*
H2	0.3996 (9)	0.884 (3)	0.6056 (11)	0.036 (6)*
H3	0.3712 (7)	0.753 (4)	0.5031 (10)	0.033 (6)*
H5	0.4670 (8)	0.155 (3)	0.5170 (11)	0.036 (6)*
H7	0.5240 (7)	0.097 (3)	0.6024 (8)	0.017 (5)*
H81	0.5617 (8)	0.033 (3)	0.7554 (6)	0.018 (5)*
H82	0.5676 (9)	−0.067 (3)	0.6831 (10)	0.028 (5)*
H91	0.6237 (11)	0.351 (3)	0.7316 (12)	0.052 (8)*
H92	0.6344 (10)	0.217 (5)	0.6640 (6)	0.048 (8)*
H11	0.6818 (9)	−0.251 (4)	0.6764 (6)	0.034 (6)*
H13	0.6501 (8)	0.365 (3)	0.8521 (11)	0.038 (6)*
H15	0.6893 (9)	0.299 (4)	0.9553 (9)	0.037 (6)*
H16	0.7477 (10)	−0.026 (5)	0.9748 (8)	0.045 (8)*
H17	0.7634 (8)	−0.323 (3)	0.8917 (12)	0.041 (7)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Zn1	0.02395 (17)	0.01667 (17)	0.01391 (15)	0.000	−0.00209 (10)	0.000
Cl1	0.0418 (3)	0.0423 (3)	0.0191 (2)	0.0051 (2)	−0.01249 (18)	−0.00457 (18)
O1	0.0394 (7)	0.0195 (6)	0.0173 (6)	0.0091 (5)	−0.0061 (5)	−0.0035 (5)
N1	0.0163 (6)	0.0165 (7)	0.0174 (6)	0.0011 (5)	−0.0005 (5)	0.0026 (5)
C1	0.0215 (7)	0.0158 (8)	0.0153 (7)	0.0005 (6)	−0.0003 (6)	0.0006 (6)
N2	0.0211 (7)	0.0231 (8)	0.0262 (7)	0.0056 (6)	−0.0016 (6)	−0.0016 (6)
C2	0.0264 (9)	0.0193 (8)	0.0222 (8)	0.0065 (7)	0.0000 (6)	0.0018 (6)
C3	0.0227 (8)	0.0247 (9)	0.0212 (8)	0.0039 (7)	−0.0029 (6)	0.0072 (7)
C4	0.0236 (8)	0.0268 (8)	0.0142 (7)	−0.0009 (7)	−0.0026 (6)	−0.0005 (6)
C5	0.0231 (8)	0.0214 (8)	0.0172 (7)	0.0029 (6)	−0.0001 (6)	−0.0021 (6)
C6	0.0185 (7)	0.0168 (8)	0.0148 (7)	0.0013 (6)	−0.0005 (5)	0.0007 (6)
C7	0.0186 (7)	0.0173 (8)	0.0186 (7)	0.0030 (6)	0.0006 (6)	−0.0001 (6)
C8	0.0183 (7)	0.0173 (8)	0.0201 (7)	0.0020 (6)	−0.0025 (6)	0.0032 (6)
C9	0.0186 (8)	0.0281 (10)	0.0444 (11)	−0.0022 (7)	−0.0044 (7)	0.0164 (9)
C10	0.0154 (7)	0.0226 (9)	0.0319 (10)	−0.0029 (6)	−0.0015 (7)	0.0075 (7)
C11	0.0206 (8)	0.0281 (9)	0.0246 (8)	−0.0026 (7)	−0.0040 (6)	0.0022 (7)
C12	0.0152 (7)	0.0179 (8)	0.0298 (9)	−0.0013 (6)	0.0030 (6)	0.0036 (7)
C13	0.0264 (9)	0.0199 (9)	0.0431 (11)	−0.0029 (7)	0.0094 (8)	−0.0036 (8)
C15	0.0408 (11)	0.0315 (11)	0.0359 (10)	−0.0118 (9)	0.0098 (8)	−0.0126 (9)
C16	0.0399 (11)	0.0382 (12)	0.0249 (10)	−0.0122 (8)	−0.0022 (8)	0.0001 (8)
C17	0.0265 (9)	0.0293 (10)	0.0275 (9)	−0.0020 (7)	−0.0043 (7)	0.0047 (7)
C18	0.0179 (7)	0.0194 (8)	0.0241 (8)	−0.0010 (6)	0.0010 (6)	0.0018 (6)

Geometric parameters (Å, º) top

Zn1—O1	1.907 (1)	C7—H7	0.994 (9)
Zn1—O1ⁱ	1.907 (1)	C8—C9	1.523 (2)
Zn1—N1	2.016 (1)	C8—H81	0.989 (9)
Zn1—N1ⁱ	2.016 (1)	C8—H82	0.994 (10)
Cl1—C4	1.745 (2)	C9—C10	1.502 (2)
O1—C1	1.312 (2)	C9—H91	0.998 (10)
N1—C7	1.282 (2)	C9—H92	1.004 (10)
N1—C8	1.469 (2)	C10—C11	1.366 (3)
C1—C2	1.419 (2)	C10—C12	1.439 (3)
C1—C6	1.427 (2)	C11—H11	0.990 (10)
N2—C18	1.374 (2)	C12—C13	1.402 (3)
N2—C11	1.383 (2)	C12—C18	1.415 (2)
N2—H2N	0.870 (10)	C13—C15	1.379 (3)
C2—C3	1.374 (2)	C13—H13	0.998 (10)
C2—H2	0.994 (10)	C15—C16	1.405 (3)
C3—C4	1.391 (3)	C15—H15	0.990 (10)
C3—H3	1.001 (10)	C16—C17	1.382 (3)
C4—C5	1.370 (2)	C16—H16	0.992 (10)
C5—C6	1.410 (2)	C17—C18	1.398 (2)
C5—H5	0.999 (10)	C17—H17	0.996 (10)
C6—C7	1.453 (2)

O1—Zn1—O1ⁱ	116.62 (8)	N1—C8—H81	108.7 (12)
O1—Zn1—N1	95.57 (5)	C9—C8—H81	109.5 (12)
O1—Zn1—N1ⁱ	125.55 (6)	N1—C8—H82	109.4 (14)
O1ⁱ—Zn1—N1	125.55 (6)	C9—C8—H82	110.3 (13)
O1ⁱ—Zn1—N1ⁱ	95.57 (5)	H81—C8—H82	107.8 (18)
N1—Zn1—N1ⁱ	99.56 (8)	C10—C9—C8	110.87 (15)
C1—O1—Zn1	124.38 (11)	C10—C9—H91	109.5 (17)
C7—N1—C8	118.25 (14)	C8—C9—H91	109.0 (16)
C7—N1—Zn1	120.68 (11)	C10—C9—H92	110.3 (16)
C8—N1—Zn1	119.96 (10)	C8—C9—H92	110.3 (15)
O1—C1—C2	118.25 (15)	H91—C9—H92	107 (2)
O1—C1—C6	124.63 (15)	C11—C10—C12	106.68 (16)
C2—C1—C6	117.12 (14)	C11—C10—C9	127.04 (19)
C18—N2—C11	109.06 (15)	C12—C10—C9	126.20 (17)
C18—N2—H2N	125.3 (18)	C10—C11—N2	109.81 (16)
C11—N2—H2N	125.7 (18)	C10—C11—H11	129.7 (14)
C3—C2—C1	122.28 (16)	N2—C11—H11	120.4 (14)
C3—C2—H2	118.2 (14)	C13—C12—C18	118.94 (17)
C1—C2—H2	119.6 (14)	C13—C12—C10	134.06 (17)
C2—C3—C4	119.47 (15)	C18—C12—C10	106.99 (15)
C2—C3—H3	119.0 (14)	C15—C13—C12	118.76 (19)
C4—C3—H3	121.5 (14)	C15—C13—H13	120.0 (14)
C5—C4—C3	120.68 (16)	C12—C13—H13	121.2 (14)
C5—C4—Cl1	119.65 (14)	C13—C15—C16	121.40 (19)
C3—C4—Cl1	119.66 (13)	C13—C15—H15	118.7 (15)
C4—C5—C6	120.98 (16)	C16—C15—H15	119.8 (15)
C4—C5—H5	118.2 (14)	C17—C16—C15	121.4 (2)
C6—C5—H5	120.8 (14)	C17—C16—H16	120.4 (16)
C5—C6—C1	119.38 (14)	C15—C16—H16	118.2 (16)
C5—C6—C7	115.93 (14)	C16—C17—C18	117.02 (18)
C1—C6—C7	124.69 (14)	C16—C17—H17	121.9 (15)
N1—C7—C6	126.44 (15)	C18—C17—H17	121.1 (15)
N1—C7—H7	118.8 (12)	N2—C18—C17	130.10 (17)
C6—C7—H7	114.6 (12)	N2—C18—C12	107.45 (15)
N1—C8—C9	111.15 (14)	C17—C18—C12	122.43 (17)

O1ⁱ—Zn1—O1—C1	153.77 (15)	C1—C6—C7—N1	2.3 (3)
N1—Zn1—O1—C1	19.16 (14)	C7—N1—C8—C9	104.80 (18)
N1ⁱ—Zn1—O1—C1	−86.78 (15)	Zn1—N1—C8—C9	−87.15 (16)
O1—Zn1—N1—C7	−18.84 (14)	N1—C8—C9—C10	169.91 (16)
O1ⁱ—Zn1—N1—C7	−147.38 (12)	C8—C9—C10—C11	79.8 (2)
N1ⁱ—Zn1—N1—C7	108.67 (14)	C8—C9—C10—C12	−96.6 (2)
O1—Zn1—N1—C8	173.41 (12)	C12—C10—C11—N2	−0.1 (2)
O1ⁱ—Zn1—N1—C8	44.87 (14)	C9—C10—C11—N2	−177.12 (16)
N1ⁱ—Zn1—N1—C8	−59.09 (10)	C18—N2—C11—C10	0.3 (2)
Zn1—O1—C1—C2	167.80 (12)	C11—C10—C12—C13	178.99 (19)
Zn1—O1—C1—C6	−11.6 (2)	C9—C10—C12—C13	−4.0 (3)
O1—C1—C2—C3	−176.76 (17)	C11—C10—C12—C18	−0.05 (19)
C6—C1—C2—C3	2.7 (3)	C9—C10—C12—C18	176.96 (16)
C1—C2—C3—C4	−0.4 (3)	C18—C12—C13—C15	−0.2 (3)
C2—C3—C4—C5	−1.9 (3)	C10—C12—C13—C15	−179.14 (19)
C2—C3—C4—Cl1	177.25 (14)	C12—C13—C15—C16	0.4 (3)
C3—C4—C5—C6	1.8 (3)	C13—C15—C16—C17	−0.1 (3)
Cl1—C4—C5—C6	−177.31 (13)	C15—C16—C17—C18	−0.4 (3)
C4—C5—C6—C1	0.5 (3)	C11—N2—C18—C17	−178.80 (18)
C4—C5—C6—C7	−179.84 (16)	C11—N2—C18—C12	−0.31 (19)
O1—C1—C6—C5	176.72 (16)	C16—C17—C18—N2	178.95 (18)
C2—C1—C6—C5	−2.7 (2)	C16—C17—C18—C12	0.7 (3)
O1—C1—C6—C7	−2.9 (3)	C13—C12—C18—N2	−178.99 (16)
C2—C1—C6—C7	177.69 (15)	C10—C12—C18—N2	0.22 (19)
C8—N1—C7—C6	179.43 (15)	C13—C12—C18—C17	−0.4 (3)
Zn1—N1—C7—C6	11.5 (2)	C10—C12—C18—C17	178.85 (16)
C5—C6—C7—N1	−177.31 (16)

Symmetry code: (i) −x+1, y, −z+3/2.

Experimental details

Crystal data
Chemical formula	[Zn(C₁₇H₁₄ClN₂O)₂]
M_r	660.87
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	128
a, b, c (Å)	25.8989 (3), 5.4960 (1), 20.6138 (3)
β (°)	91.801 (1)
V (Å³)	2932.73 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.06
Crystal size (mm)	0.50 × 0.30 × 0.17

Data collection
Diffractometer	Bruker APEXII diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.714, 0.840
No. of measured, independent and observed [I > 2σ(I)] reflections	17664, 3352, 3023
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.025, 0.100, 1.21
No. of reflections	3352
No. of parameters	251
No. of restraints	14
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.55, −0.56

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2008).

Selected geometric parameters (Å, º) top

Zn1—O1	1.907 (1)	Zn1—N1	2.016 (1)

O1—Zn1—O1ⁱ	116.62 (8)	O1—Zn1—N1ⁱ	125.55 (6)
O1—Zn1—N1	95.57 (5)	N1—Zn1—N1ⁱ	99.56 (8)

Symmetry code: (i) −x+1, y, −z+3/2.

Acknowledgements

The authors thank the University of Canterbury, New Zealand, for the diffraction measurements, and the Science Fund (12–02-03–2031) for supporting this study.

References

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