{N-Methyl-N′-[1-(pyridin-2-yl)ethyl­idene]ethane-1,2-diamine-κ3N,N′,N′′}­bis(thio­cyanato-κN)zinc(II)

Li, X.-W.

doi:10.1107/S1600536811019945

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 7| July 2011| Page m829

doi:10.1107/S1600536811019945

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{N-Methyl-N′-[1-(pyridin-2-yl)ethylidene]ethane-1,2-diamine-κ³N,N′,N′′}bis(thiocyanato-κN)zinc(II)

Xian-Wen Li ^a ^*

^aDepartment of Chemistry and Chemical Engineering, Minjiang University, Fuzhou 350108, People's Republic of China
^*Correspondence e-mail: xianwen_li@126.com

(Received 24 May 2011; accepted 25 May 2011; online 4 June 2011)

In the title compound, [Zn(NCS)₂(C₁₀H₁₅N₃)], the Zn atom is five-coordinated by the three N-donor atoms of the Schiff base ligand and by two N atoms from two thiocyanate anions, forming a distorted ZnN₅ trigonal–bipyramidal coordination geometry for the metal ion. The side chain of the ligand is disordered over two sets of sites in a 0.655 (12):0.345 (12) ratio. In the crystal, molecules are linked by N—H⋯S hydrogen bonds, generating [100] chains.

Related literature

For the biological activity of Schiff base compounds, see: Panneerselvam et al. (2005 ); Shi et al. (2007 ); Singh et al. (2006 , 2007 ); Zhong et al. (2006 ). For the Schiff base complexes we reported previously, see: Li & Qiu (2008a ,b ).

Experimental

Crystal data

[Zn(NCS)₂(C₁₀H₁₅N₃)]
M_r = 358.78
Monoclinic, P 2₁ /n
a = 7.6674 (3) Å
b = 14.8062 (5) Å
c = 14.3766 (6) Å
β = 101.853 (2)°
V = 1597.30 (11) Å³
Z = 4
Mo Kα radiation
μ = 1.80 mm⁻¹
T = 298 K
0.20 × 0.20 × 0.18 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2004 ) T_min = 0.715, T_max = 0.738
9004 measured reflections
3352 independent reflections
2095 reflections with I > 2σ(I)
R_int = 0.029

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.105
S = 1.02
3352 reflections
201 parameters
12 restraints
H-atom parameters constrained
Δρ_max = 0.46 e Å⁻³
Δρ_min = −0.46 e Å⁻³

Table 1
Selected bond lengths (Å)

Zn1—N5	1.974 (4)
Zn1—N4	1.986 (4)
Zn1—N2	2.088 (3)
Zn1—N3	2.163 (4)
Zn1—N1	2.195 (3)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3A⋯S1ⁱ	0.91	2.66	3.551 (5)	165
Symmetry code: (i) x-1, y, z.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811019945/hb5892sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811019945/hb5892Isup2.hkl

checkCIF report

Comment top

Schiff base compounds have been reported to have excellent biological activity (Shi et al., 2007; Panneerselvam et al., 2005). The metal complexes derived from the Schiff bases also have excellent biological activity (Singh et al., 2006, 2007; Zhong et al., 2006). As a continuation of our work on Schiff base complexes (Li & Qiu, 2008a,b), we report herein the crystal structure of the title zinc complex, (I).

In the title mononuclear zinc(II) complex, the Zn atom is five-coordinated by the three donor atoms (N1, N2, and N3) of the Schiff baes ligand, and two N atoms from two thiocyanate ligands, forming a slightly distorted trigonal-bipyramidal geometry (Fig. 1). The coordinate bond values (Table 1) are within normal ranges.

Related literature top

For the biological activity of Schiff base compounds, see: Panneerselvam et al. (2005); Shi et al. (2007); Singh et al. (2006, 2007); Zhong et al. (2006). For the Schiff base complexes we reported previously, see: Li & Qiu (2008a,b).

Experimental top

The title compound was obtained by the reaction of equimolar quantities (0.1 mmol each) of 2-acetylpyridine, N-methylethane-1,2-diamine, sodium thiocyanate, and zinc acetate in ethanol. Colorless blocks of (I) were obtained by the slow evaporation of the filtrate in air.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids. Only the major component of the disordered group is shown.

{N-Methyl-N'-[1-(pyridin-2-yl)ethylidene]ethane-1,2-diamine- κ³N,N',N''}bis(thiocyanato-κN)zinc(II) top

Crystal data top

[Zn(NCS)₂(C₁₀H₁₅N₃)]	F(000) = 736
M_r = 358.78	D_x = 1.492 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2372 reflections
a = 7.6674 (3) Å	θ = 2.6–25.1°
b = 14.8062 (5) Å	µ = 1.80 mm⁻¹
c = 14.3766 (6) Å	T = 298 K
β = 101.853 (2)°	Block, colorless
V = 1597.30 (11) Å³	0.20 × 0.20 × 0.18 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	3352 independent reflections
Radiation source: fine-focus sealed tube	2095 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.029
ω scans	θ_max = 26.7°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −9→9
T_min = 0.715, T_max = 0.738	k = −17→18
9004 measured reflections	l = −18→11

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.105	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0323P)² + 1.952P] where P = (F_o² + 2F_c²)/3
3352 reflections	(Δ/σ)_max = 0.001
201 parameters	Δρ_max = 0.46 e Å⁻³
12 restraints	Δρ_min = −0.46 e Å⁻³

Crystal data top

[Zn(NCS)₂(C₁₀H₁₅N₃)]	V = 1597.30 (11) Å³
M_r = 358.78	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.6674 (3) Å	µ = 1.80 mm⁻¹
b = 14.8062 (5) Å	T = 298 K
c = 14.3766 (6) Å	0.20 × 0.20 × 0.18 mm
β = 101.853 (2)°

Data collection top

Bruker APEXII CCD diffractometer	3352 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	2095 reflections with I > 2σ(I)
T_min = 0.715, T_max = 0.738	R_int = 0.029
9004 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	12 restraints
wR(F²) = 0.105	H-atom parameters constrained
S = 1.02	Δρ_max = 0.46 e Å⁻³
3352 reflections	Δρ_min = −0.46 e Å⁻³
201 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	Occ. (<1)
Zn1	0.72087 (6)	−0.07353 (3)	0.71636 (3)	0.05504 (17)
S1	1.28221 (17)	−0.15205 (10)	0.89256 (10)	0.0835 (4)
S2	0.3366 (2)	−0.32564 (11)	0.66375 (10)	0.1063 (6)
N1	0.7424 (4)	−0.0555 (2)	0.5676 (2)	0.0524 (8)
N2	0.6777 (4)	0.0641 (2)	0.6890 (2)	0.0559 (8)
N4	0.9697 (5)	−0.1140 (3)	0.7651 (3)	0.0760 (11)
N5	0.5583 (5)	−0.1782 (2)	0.6923 (2)	0.0684 (10)
C1	0.7390 (5)	0.0309 (3)	0.5392 (3)	0.0515 (9)
C2	0.7683 (5)	0.0539 (3)	0.4504 (3)	0.0628 (11)
H2	0.7670	0.1142	0.4319	0.075*
C3	0.7993 (6)	−0.0131 (4)	0.3901 (3)	0.0708 (13)
H3	0.8193	0.0015	0.3303	0.085*
C4	0.8009 (6)	−0.1007 (4)	0.4174 (3)	0.0706 (13)
H4	0.8207	−0.1469	0.3770	0.085*
C5	0.7719 (6)	−0.1192 (3)	0.5074 (3)	0.0629 (11)
H5	0.7731	−0.1792	0.5268	0.075*
C6	0.7014 (5)	0.0970 (3)	0.6107 (3)	0.0577 (10)
C7	0.6971 (7)	0.1958 (3)	0.5876 (4)	0.0877 (15)
H7A	0.6442	0.2284	0.6325	0.132*
H7B	0.6279	0.2052	0.5247	0.132*
H7C	0.8164	0.2172	0.5907	0.132*
C11	1.1008 (6)	−0.1300 (3)	0.8180 (3)	0.0573 (10)
C12	0.4653 (6)	−0.2395 (3)	0.6815 (3)	0.0586 (10)
C8	0.6362 (7)	0.1164 (3)	0.7662 (3)	0.0810 (14)	0.655 (12)
H8A	0.5502	0.1631	0.7417	0.097*	0.655 (12)
H8B	0.7431	0.1451	0.8016	0.097*	0.655 (12)
C9	0.5577 (12)	0.0508 (5)	0.8318 (5)	0.074 (3)	0.655 (12)
H9A	0.5582	0.0803	0.8921	0.089*	0.655 (12)
H9B	0.4349	0.0371	0.8026	0.089*	0.655 (12)
C10	0.7978 (14)	−0.0366 (8)	0.9293 (6)	0.089 (3)	0.655 (12)
H10A	0.7586	−0.0160	0.9849	0.133*	0.655 (12)
H10B	0.8964	−0.0004	0.9196	0.133*	0.655 (12)
H10C	0.8346	−0.0986	0.9377	0.133*	0.655 (12)
N3	0.6540 (6)	−0.0290 (3)	0.8480 (2)	0.0814 (12)	0.655 (12)
H3A	0.5729	−0.0703	0.8591	0.098*	0.655 (12)
C8'	0.6362 (7)	0.1164 (3)	0.7662 (3)	0.0810 (14)	0.345 (12)
H8'A	0.5082	0.1233	0.7582	0.097*	0.345 (12)
H8'B	0.6893	0.1760	0.7673	0.097*	0.345 (12)
C9'	0.709 (2)	0.0678 (7)	0.8562 (7)	0.097 (7)	0.345 (12)
H9'A	0.6658	0.0959	0.9081	0.116*	0.345 (12)
H9'B	0.8382	0.0719	0.8702	0.116*	0.345 (12)
C10'	0.723 (2)	−0.0647 (13)	0.9393 (8)	0.066 (5)	0.345 (12)
H10D	0.6699	−0.0338	0.9854	0.099*	0.345 (12)
H10E	0.8497	−0.0565	0.9546	0.099*	0.345 (12)
H10F	0.6955	−0.1279	0.9400	0.099*	0.345 (12)
N3'	0.6540 (6)	−0.0290 (3)	0.8480 (2)	0.0814 (12)	0.345 (12)
H3'A	0.5331	−0.0302	0.8394	0.098*	0.345 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Zn1	0.0644 (3)	0.0492 (3)	0.0518 (3)	0.0000 (2)	0.0128 (2)	0.0037 (2)
S1	0.0678 (8)	0.0948 (10)	0.0845 (9)	0.0061 (7)	0.0077 (6)	−0.0070 (7)
S2	0.1434 (14)	0.0975 (11)	0.0869 (9)	−0.0621 (10)	0.0447 (9)	−0.0190 (8)
N1	0.062 (2)	0.0456 (19)	0.0502 (18)	−0.0062 (15)	0.0126 (15)	−0.0006 (15)
N2	0.061 (2)	0.0461 (18)	0.061 (2)	0.0029 (16)	0.0128 (16)	−0.0033 (16)
N4	0.074 (3)	0.082 (3)	0.073 (3)	0.008 (2)	0.018 (2)	0.021 (2)
N5	0.082 (3)	0.055 (2)	0.069 (2)	−0.007 (2)	0.017 (2)	0.0074 (18)
C1	0.042 (2)	0.057 (2)	0.053 (2)	−0.0039 (18)	0.0023 (17)	0.0080 (19)
C2	0.055 (3)	0.071 (3)	0.059 (3)	−0.008 (2)	0.003 (2)	0.020 (2)
C3	0.064 (3)	0.100 (4)	0.048 (2)	−0.015 (3)	0.010 (2)	0.009 (3)
C4	0.068 (3)	0.092 (4)	0.054 (3)	−0.010 (3)	0.018 (2)	−0.012 (2)
C5	0.072 (3)	0.056 (3)	0.064 (3)	−0.005 (2)	0.022 (2)	−0.002 (2)
C6	0.054 (2)	0.044 (2)	0.070 (3)	−0.0030 (18)	0.002 (2)	0.004 (2)
C7	0.114 (4)	0.048 (3)	0.099 (4)	−0.001 (3)	0.015 (3)	0.008 (3)
C11	0.065 (3)	0.051 (2)	0.060 (3)	−0.005 (2)	0.024 (2)	0.003 (2)
C12	0.075 (3)	0.059 (3)	0.045 (2)	−0.002 (2)	0.022 (2)	0.007 (2)
C8	0.097 (4)	0.060 (3)	0.089 (4)	−0.004 (3)	0.025 (3)	−0.019 (3)
C9	0.081 (6)	0.080 (6)	0.062 (4)	0.033 (4)	0.018 (4)	−0.005 (4)
C10	0.111 (7)	0.092 (7)	0.059 (5)	0.030 (5)	0.010 (5)	−0.003 (4)
N3	0.092 (3)	0.097 (3)	0.057 (2)	−0.012 (3)	0.020 (2)	−0.009 (2)
C8'	0.097 (4)	0.060 (3)	0.089 (4)	−0.004 (3)	0.025 (3)	−0.019 (3)
C9'	0.096 (14)	0.151 (18)	0.044 (8)	−0.025 (12)	0.015 (8)	−0.013 (9)
C10'	0.090 (12)	0.066 (10)	0.046 (7)	0.005 (9)	0.025 (8)	0.016 (7)
N3'	0.092 (3)	0.097 (3)	0.057 (2)	−0.012 (3)	0.020 (2)	−0.009 (2)

Geometric parameters (Å, º) top

Zn1—N5	1.974 (4)	C5—H5	0.9300
Zn1—N4	1.986 (4)	C6—C7	1.499 (6)
Zn1—N2	2.088 (3)	C7—H7A	0.9600
Zn1—N3	2.163 (4)	C7—H7B	0.9600
Zn1—N1	2.195 (3)	C7—H7C	0.9600
S1—C11	1.605 (5)	C8—C9	1.559 (7)
S2—C12	1.601 (5)	C8—H8A	0.9700
N1—C5	1.330 (5)	C8—H8B	0.9700
N1—C1	1.342 (5)	C9—N3	1.388 (6)
N2—C6	1.273 (5)	C9—H9A	0.9700
N2—C8	1.441 (5)	C9—H9B	0.9700
N4—C11	1.154 (5)	C10—N3	1.437 (7)
N5—C12	1.145 (5)	C10—H10A	0.9600
C1—C2	1.383 (5)	C10—H10B	0.9600
C1—C6	1.490 (6)	C10—H10C	0.9600
C2—C3	1.371 (6)	N3—H3A	0.9100
C2—H2	0.9300	C9'—H9'A	0.9700
C3—C4	1.354 (6)	C9'—H9'B	0.9700
C3—H3	0.9300	C10'—H10D	0.9600
C4—C5	1.385 (6)	C10'—H10E	0.9600
C4—H4	0.9300	C10'—H10F	0.9600

N5—Zn1—N4	110.56 (16)	C6—C7—H7A	109.5
N5—Zn1—N2	131.51 (14)	C6—C7—H7B	109.5
N4—Zn1—N2	117.70 (15)	H7A—C7—H7B	109.5
N5—Zn1—N3	97.92 (16)	C6—C7—H7C	109.5
N4—Zn1—N3	99.59 (16)	H7A—C7—H7C	109.5
N2—Zn1—N3	79.09 (15)	H7B—C7—H7C	109.5
N5—Zn1—N1	95.51 (13)	N4—C11—S1	179.4 (4)
N4—Zn1—N1	96.97 (14)	N5—C12—S2	178.5 (4)
N2—Zn1—N1	74.85 (12)	N2—C8—C9	107.8 (4)
N3—Zn1—N1	153.44 (15)	N2—C8—H8A	110.2
C5—N1—C1	118.3 (3)	C9—C8—H8A	110.2
C5—N1—Zn1	127.2 (3)	N2—C8—H8B	110.2
C1—N1—Zn1	114.3 (3)	C9—C8—H8B	110.2
C6—N2—C8	124.6 (4)	H8A—C8—H8B	108.5
C6—N2—Zn1	119.6 (3)	N3—C9—C8	111.9 (5)
C8—N2—Zn1	115.5 (3)	N3—C9—H9A	109.2
C11—N4—Zn1	159.8 (4)	C8—C9—H9A	109.2
C12—N5—Zn1	177.7 (4)	N3—C9—H9B	109.2
N1—C1—C2	121.3 (4)	C8—C9—H9B	109.2
N1—C1—C6	114.3 (3)	H9A—C9—H9B	107.9
C2—C1—C6	124.4 (4)	N3—C10—H10A	109.5
C3—C2—C1	119.2 (4)	N3—C10—H10B	109.5
C3—C2—H2	120.4	H10A—C10—H10B	109.5
C1—C2—H2	120.4	N3—C10—H10C	109.5
C4—C3—C2	120.2 (4)	H10A—C10—H10C	109.5
C4—C3—H3	119.9	H10B—C10—H10C	109.5
C2—C3—H3	119.9	C9—N3—C10	119.7 (7)
C3—C4—C5	117.8 (4)	C9—N3—Zn1	109.1 (3)
C3—C4—H4	121.1	C10—N3—Zn1	114.1 (5)
C5—C4—H4	121.1	C9—N3—H3A	104.0
N1—C5—C4	123.3 (4)	C10—N3—H3A	104.0
N1—C5—H5	118.4	Zn1—N3—H3A	104.0
C4—C5—H5	118.4	H9'A—C9'—H9'B	108.1
N2—C6—C1	116.2 (3)	H10D—C10'—H10E	109.5
N2—C6—C7	124.7 (4)	H10D—C10'—H10F	109.5
C1—C6—C7	119.1 (4)	H10E—C10'—H10F	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···S1ⁱ	0.91	2.66	3.551 (5)	165

Symmetry code: (i) x−1, y, z.

Experimental details

Crystal data
Chemical formula	[Zn(NCS)₂(C₁₀H₁₅N₃)]
M_r	358.78
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	7.6674 (3), 14.8062 (5), 14.3766 (6)
β (°)	101.853 (2)
V (Å³)	1597.30 (11)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.80
Crystal size (mm)	0.20 × 0.20 × 0.18

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2004)
T_min, T_max	0.715, 0.738
No. of measured, independent and observed [I > 2σ(I)] reflections	9004, 3352, 2095
R_int	0.029
(sin θ/λ)_max (Å⁻¹)	0.633

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.105, 1.02
No. of reflections	3352
No. of parameters	201
No. of restraints	12
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.46, −0.46

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Zn1—N5	1.974 (4)	Zn1—N3	2.163 (4)
Zn1—N4	1.986 (4)	Zn1—N1	2.195 (3)
Zn1—N2	2.088 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···S1ⁱ	0.91	2.66	3.551 (5)	165

Symmetry code: (i) x−1, y, z.

Acknowledgements

We thank Minjiang University for financial support.

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