Dibromido[N-propyl-N′-(2-pyridylmethyl­idene)ethane-1,2-diamine]zinc(II)

Zhu, X.-W.; Yang, X.-Z.

doi:10.1107/S1600536808023660

metal-organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 8| August 2008| Pages m1094-m1095

doi:10.1107/S1600536808023660

Open

access

Dibromido[N-propyl-N′-(2-pyridylmethylidene)ethane-1,2-diamine]zinc(II)

Xue-Wen Zhu ^a ^* and Xu-Zhao Yang ^a

^aKey Laboratory of Surface and Interface Science of Henan, School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, People's Republic of China
^*Correspondence e-mail: xuewen_zhu@126.com

(Received 25 July 2008; accepted 27 July 2008; online 31 July 2008)

The title complex, [ZnBr₂(C₁₁H₁₇N₃)], is a mononuclear zinc(II) compound derived from the Schiff base N-propyl-N′-(1-pyridin-2-ylmethylidene)ethane-1,2-diamine. The Zn^II atom is five-coordinate, binding to the imine N, pyridine N, and amine N atoms of the Schiff base ligand and to two bromide anions in a distorted trigonal-bipyramidal coordination geometry. Adjacent molecules are linked through intermolecular N—H⋯Br hydrogen bonds, forming dimers.

Related literature

For background to the chemistry of Schiff base complexes, see: Ali et al. (2008 ); Biswas et al. (2008 ); Chen et al. (2008 ); Darensbourg & Frantz (2007 ); Habibi et al. (2007 ); Kawamoto et al. (2008 ); Lipscomb & Sträter (1996 ); Tomat et al. (2007 ); Wu et al. (2008 ); Yuan et al. (2007 ). For related structures, see: Dapporto et al. (2001 ); You & Zhu (2006 ).

Experimental

Crystal data

[ZnBr₂(C₁₁H₁₇N₃)]
M_r = 416.47
Monoclinic, P 2₁ /n
a = 8.252 (4) Å
b = 12.249 (5) Å
c = 14.726 (6) Å
β = 94.562 (7)°
V = 1483.8 (11) Å³
Z = 4
Mo Kα radiation
μ = 7.02 mm⁻¹
T = 298 (2) K
0.32 × 0.30 × 0.30 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2004 ) T_min = 0.212, T_max = 0.227 (expected range = 0.114–0.122)
12333 measured reflections
3378 independent reflections
2167 reflections with I > 2σ(I)
R_int = 0.083

Refinement

R[F² > 2σ(F²)] = 0.045
wR(F²) = 0.105
S = 1.01
3378 reflections
159 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.91 e Å⁻³
Δρ_min = −0.80 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Zn1—N2	2.095 (4)
Zn1—N3	2.202 (4)
Zn1—N1	2.303 (4)
Zn1—Br2	2.3954 (13)
Zn1—Br1	2.4102 (11)

N2—Zn1—N3	77.83 (16)
N2—Zn1—N1	73.04 (15)
N3—Zn1—N1	149.43 (15)
N2—Zn1—Br2	131.24 (11)
N3—Zn1—Br2	100.86 (11)
N1—Zn1—Br2	91.57 (11)
N2—Zn1—Br1	111.33 (12)
N3—Zn1—Br1	99.08 (11)
N1—Zn1—Br1	99.94 (11)
Br2—Zn1—Br1	116.88 (4)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3A⋯Br1ⁱ	0.90 (5)	2.80 (4)	3.539 (4)	141 (5)
Symmetry code: (i) -x, -y+1, -z+2.

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/S1600536808023660/sj2523sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808023660/sj2523Isup2.hkl

checkCIF report

Comment top

Schiff bases have widely been used as versatile ligands in coordination chemistry (Biswas et al., 2008; Wu et al., 2008; Kawamoto et al., 2008; Ali et al., 2008; Habibi et al., 2007), and their metal complexes are of great interest in many fields (Chen et al., 2008; Yuan et al., 2007; Tomat et al., 2007; Darensbourg & Frantz, 2007). Zinc(II) is an important element in biological systems, functions as the active site of hydrolytic enzymes, such as carboxypeptidase and carbonic anhydrase where it is in a hard-donor coordination environment of nitrogen and oxygen ligands (Lipscomb & Sträter, 1996). In this paper, a new zinc(II) complex, (I), Fig. 1, with the Schiff base ligand N-propyl-N'-(1-pyridin-2-ylmethylidene)ethane-1,2-diamine has been synthesized and structurally characterized.

The Zn^II atom in (I) is five-coordinated by one imine N, one pyridine N, and one amine N atoms of the Schiff base ligand, and by two Br^- anions, in a distorted trigonal-bipyramidal coordination geometry. The coordinate bond lengths (Table 1) are typical and comparable to the corresponding values observed in similar zinc(II) Schiff base complexes (You & Zhu, 2006; Dapporto et al., 2001). The bond angle N1—Zn1—N3 in the complex is 149.43 (15)° indicating a significant distortion from trigonal-bipyramidal coordination.

In the crystal structure, adjacent molecules are linked through intermolecular N–H···Br hydrogen bonds (Table 2), forming dimers (Fig. 2).

Related literature top

For background to the chemistry of Schiff base complexes, see: Ali et al. (2008); Biswas et al. (2008); Chen et al. (2008); Darensbourg & Frantz (2007); Habibi et al. (2007); Kawamoto et al. (2008); Lipscomb & Sträter (1996); Tomat et al. (2007); Wu et al. (2008); Yuan et al. (2007). For related structures, see: Dapporto et al. (2001); You & Zhu (2006).

Experimental top

The Schiff base compound was prepared by the condensation of equimolar amounts of pyridine-2-carbaldehyde with N-propylethane-1,2-diamine in a methanol solution. The complex was prepared by the following method. To an anhydrous methanol solution (5 ml) of ZnBr₂ (22.5 mg, 0.1 mmol) was added a methanol solution (10 ml) of the Schiff base compound (19.1 mg, 0.1 mmol) with stirring. The mixture was stirred for 30 min at room temperature and filtered. Upon keeping the filtrate in air for a few days, colorless block-shaped crystals formed at the bottom of the vessel on slow evaporation of the solvent.

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 (I) with ellipsoids drawn at the 30% probability level.
	Fig. 2. The crystal packing of (I), viewed along the a axis.

Dibromido[N-propyl-N'-(2-pyridylmethylidene)ethane-1,2- diamine]zinc(II) top

Crystal data top

[ZnBr₂(C₁₁H₁₇N₃)]	F(000) = 816
M_r = 416.47	D_x = 1.864 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1994 reflections
a = 8.252 (4) Å	θ = 2.2–25.3°
b = 12.249 (5) Å	µ = 7.02 mm⁻¹
c = 14.726 (6) Å	T = 298 K
β = 94.562 (7)°	Block, colorless
V = 1483.8 (11) Å³	0.32 × 0.30 × 0.30 mm
Z = 4

Data collection top

Bruker APEXII CCD area-detector diffractometer	3378 independent reflections
Radiation source: fine-focus sealed tube	2167 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.083
ω scans	θ_max = 27.5°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −10→10
T_min = 0.212, T_max = 0.227	k = −15→15
12333 measured reflections	l = −18→19

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)] = 0.045	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.105	w = 1/[σ²(F_o²) + (0.0211P)²] where P = (F_o² + 2F_c²)/3
S = 1.01	(Δ/σ)_max = 0.001
3378 reflections	Δρ_max = 0.91 e Å⁻³
159 parameters	Δρ_min = −0.80 e Å⁻³
1 restraint	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0140 (7)

Crystal data top

[ZnBr₂(C₁₁H₁₇N₃)]	V = 1483.8 (11) Å³
M_r = 416.47	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.252 (4) Å	µ = 7.02 mm⁻¹
b = 12.249 (5) Å	T = 298 K
c = 14.726 (6) Å	0.32 × 0.30 × 0.30 mm
β = 94.562 (7)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	3378 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	2167 reflections with I > 2σ(I)
T_min = 0.212, T_max = 0.227	R_int = 0.083
12333 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.045	1 restraint
wR(F²) = 0.105	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	Δρ_max = 0.91 e Å⁻³
3378 reflections	Δρ_min = −0.80 e Å⁻³
159 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
Zn1	0.04170 (7)	0.30316 (4)	0.86078 (4)	0.02971 (19)
Br1	−0.19476 (6)	0.34399 (5)	0.94074 (4)	0.0454 (2)
Br2	0.00560 (8)	0.29983 (5)	0.69779 (4)	0.0524 (2)
N1	0.0385 (5)	0.1154 (3)	0.8679 (3)	0.0359 (10)
N2	0.2385 (5)	0.2563 (3)	0.9510 (3)	0.0338 (10)
N3	0.1741 (5)	0.4581 (3)	0.8836 (3)	0.0296 (9)
C1	0.1561 (6)	0.0745 (4)	0.9254 (3)	0.0351 (12)
C2	0.1774 (8)	−0.0353 (4)	0.9398 (4)	0.0495 (15)
H2	0.2599	−0.0611	0.9810	0.059*
C3	0.0742 (9)	−0.1061 (5)	0.8922 (5)	0.0606 (18)
H3	0.0849	−0.1811	0.9009	0.073*
C4	−0.0449 (8)	−0.0652 (5)	0.8318 (5)	0.0575 (17)
H4	−0.1150	−0.1117	0.7978	0.069*
C5	−0.0591 (7)	0.0466 (5)	0.8222 (4)	0.0489 (15)
H5	−0.1412	0.0743	0.7818	0.059*
C6	0.2635 (6)	0.1575 (4)	0.9712 (4)	0.0367 (12)
H6	0.3474	0.1373	1.0138	0.044*
C7	0.3456 (6)	0.3442 (4)	0.9865 (4)	0.0396 (13)
H7A	0.4553	0.3172	1.0003	0.048*
H7B	0.3068	0.3745	1.0417	0.048*
C8	0.3422 (6)	0.4295 (4)	0.9126 (4)	0.0375 (13)
H8A	0.4004	0.4941	0.9352	0.045*
H8B	0.3958	0.4016	0.8611	0.045*
C9	0.1638 (6)	0.5399 (4)	0.8098 (4)	0.0400 (13)
H9A	0.1939	0.5061	0.7540	0.048*
H9B	0.2404	0.5984	0.8252	0.048*
C10	−0.0046 (6)	0.5869 (4)	0.7943 (4)	0.0426 (14)
H10A	−0.0825	0.5278	0.7857	0.051*
H10B	−0.0298	0.6277	0.8478	0.051*
C11	−0.0207 (7)	0.6607 (5)	0.7126 (4)	0.0641 (19)
H11A	0.0663	0.7129	0.7167	0.096*
H11B	−0.1230	0.6983	0.7108	0.096*
H11C	−0.0158	0.6180	0.6582	0.096*
H3A	0.130 (7)	0.491 (4)	0.930 (3)	0.080*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Zn1	0.0321 (3)	0.0296 (3)	0.0266 (3)	0.0004 (2)	−0.0029 (2)	−0.0032 (3)
Br1	0.0399 (3)	0.0451 (4)	0.0526 (4)	−0.0043 (2)	0.0125 (3)	−0.0179 (3)
Br2	0.0811 (5)	0.0481 (4)	0.0263 (3)	0.0018 (3)	−0.0070 (3)	−0.0066 (3)
N1	0.043 (3)	0.033 (2)	0.031 (3)	−0.003 (2)	0.002 (2)	−0.001 (2)
N2	0.039 (3)	0.032 (2)	0.029 (2)	0.000 (2)	−0.003 (2)	0.001 (2)
N3	0.036 (2)	0.027 (2)	0.026 (2)	−0.0041 (17)	0.0009 (19)	−0.0019 (18)
C1	0.046 (3)	0.031 (3)	0.029 (3)	0.002 (2)	0.010 (2)	0.005 (2)
C2	0.065 (4)	0.035 (3)	0.050 (4)	0.007 (3)	0.013 (3)	0.009 (3)
C3	0.087 (5)	0.028 (3)	0.071 (5)	0.002 (3)	0.032 (4)	0.004 (3)
C4	0.070 (4)	0.037 (4)	0.067 (5)	−0.010 (3)	0.019 (4)	−0.010 (3)
C5	0.044 (3)	0.047 (4)	0.056 (4)	−0.006 (3)	0.000 (3)	−0.011 (3)
C6	0.041 (3)	0.038 (3)	0.030 (3)	0.008 (2)	−0.002 (2)	0.000 (2)
C7	0.042 (3)	0.040 (3)	0.035 (3)	−0.001 (2)	−0.011 (3)	−0.002 (3)
C8	0.037 (3)	0.033 (3)	0.041 (3)	−0.008 (2)	−0.002 (2)	−0.003 (3)
C9	0.046 (3)	0.033 (3)	0.041 (3)	−0.009 (2)	0.005 (3)	0.004 (3)
C10	0.044 (3)	0.032 (3)	0.052 (4)	0.002 (2)	0.003 (3)	0.007 (3)
C11	0.065 (4)	0.054 (4)	0.071 (5)	0.004 (3)	−0.004 (4)	0.030 (3)

Geometric parameters (Å, º) top

Zn1—N2	2.095 (4)	C4—C5	1.380 (8)
Zn1—N3	2.202 (4)	C4—H4	0.9300
Zn1—N1	2.303 (4)	C5—H5	0.9300
Zn1—Br2	2.3954 (13)	C6—H6	0.9300
Zn1—Br1	2.4102 (11)	C7—C8	1.508 (7)
N1—C5	1.313 (6)	C7—H7A	0.9700
N1—C1	1.334 (6)	C7—H7B	0.9700
N2—C6	1.259 (6)	C8—H8A	0.9700
N2—C7	1.463 (6)	C8—H8B	0.9700
N3—C8	1.461 (6)	C9—C10	1.505 (7)
N3—C9	1.477 (6)	C9—H9A	0.9700
N3—H3A	0.90 (5)	C9—H9B	0.9700
C1—C2	1.371 (7)	C10—C11	1.501 (7)
C1—C6	1.475 (7)	C10—H10A	0.9700
C2—C3	1.369 (8)	C10—H10B	0.9700
C2—H2	0.9300	C11—H11A	0.9600
C3—C4	1.367 (8)	C11—H11B	0.9600
C3—H3	0.9300	C11—H11C	0.9600

N2—Zn1—N3	77.83 (16)	N1—C5—H5	118.7
N2—Zn1—N1	73.04 (15)	C4—C5—H5	118.7
N3—Zn1—N1	149.43 (15)	N2—C6—C1	118.2 (5)
N2—Zn1—Br2	131.24 (11)	N2—C6—H6	120.9
N3—Zn1—Br2	100.86 (11)	C1—C6—H6	120.9
N1—Zn1—Br2	91.57 (11)	N2—C7—C8	106.0 (4)
N2—Zn1—Br1	111.33 (12)	N2—C7—H7A	110.5
N3—Zn1—Br1	99.08 (11)	C8—C7—H7A	110.5
N1—Zn1—Br1	99.94 (11)	N2—C7—H7B	110.5
Br2—Zn1—Br1	116.88 (4)	C8—C7—H7B	110.5
C5—N1—C1	118.1 (5)	H7A—C7—H7B	108.7
C5—N1—Zn1	128.8 (4)	N3—C8—C7	109.8 (4)
C1—N1—Zn1	113.1 (3)	N3—C8—H8A	109.7
C6—N2—C7	122.7 (4)	C7—C8—H8A	109.7
C6—N2—Zn1	121.2 (3)	N3—C8—H8B	109.7
C7—N2—Zn1	116.1 (3)	C7—C8—H8B	109.7
C8—N3—C9	112.0 (4)	H8A—C8—H8B	108.2
C8—N3—Zn1	106.6 (3)	N3—C9—C10	111.7 (4)
C9—N3—Zn1	118.3 (3)	N3—C9—H9A	109.3
C8—N3—H3A	109 (4)	C10—C9—H9A	109.3
C9—N3—H3A	105 (4)	N3—C9—H9B	109.3
Zn1—N3—H3A	106 (4)	C10—C9—H9B	109.3
N1—C1—C2	122.9 (5)	H9A—C9—H9B	107.9
N1—C1—C6	114.3 (4)	C11—C10—C9	111.9 (5)
C2—C1—C6	122.7 (5)	C11—C10—H10A	109.2
C3—C2—C1	118.4 (6)	C9—C10—H10A	109.2
C3—C2—H2	120.8	C11—C10—H10B	109.2
C1—C2—H2	120.8	C9—C10—H10B	109.2
C4—C3—C2	119.1 (6)	H10A—C10—H10B	107.9
C4—C3—H3	120.5	C10—C11—H11A	109.5
C2—C3—H3	120.5	C10—C11—H11B	109.5
C3—C4—C5	118.8 (6)	H11A—C11—H11B	109.5
C3—C4—H4	120.6	C10—C11—H11C	109.5
C5—C4—H4	120.6	H11A—C11—H11C	109.5
N1—C5—C4	122.7 (6)	H11B—C11—H11C	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···Br1ⁱ	0.90 (5)	2.80 (4)	3.539 (4)	141 (5)

Symmetry code: (i) −x, −y+1, −z+2.

Experimental details

Crystal data
Chemical formula	[ZnBr₂(C₁₁H₁₇N₃)]
M_r	416.47
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	8.252 (4), 12.249 (5), 14.726 (6)
β (°)	94.562 (7)
V (Å³)	1483.8 (11)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	7.02
Crystal size (mm)	0.32 × 0.30 × 0.30

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2004)
T_min, T_max	0.212, 0.227
No. of measured, independent and observed [I > 2σ(I)] reflections	12333, 3378, 2167
R_int	0.083
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.045, 0.105, 1.01
No. of reflections	3378
No. of parameters	159
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.91, −0.80

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

Selected geometric parameters (Å, º) top

Zn1—N2	2.095 (4)	Zn1—Br2	2.3954 (13)
Zn1—N3	2.202 (4)	Zn1—Br1	2.4102 (11)
Zn1—N1	2.303 (4)

N2—Zn1—N3	77.83 (16)	N1—Zn1—Br2	91.57 (11)
N2—Zn1—N1	73.04 (15)	N2—Zn1—Br1	111.33 (12)
N3—Zn1—N1	149.43 (15)	N3—Zn1—Br1	99.08 (11)
N2—Zn1—Br2	131.24 (11)	N1—Zn1—Br1	99.94 (11)
N3—Zn1—Br2	100.86 (11)	Br2—Zn1—Br1	116.88 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···Br1ⁱ	0.90 (5)	2.80 (4)	3.539 (4)	141 (5)

Symmetry code: (i) −x, −y+1, −z+2.

References

Ali, H. M., Mohamed Mustafa, M. I., Rizal, M. R. & Ng, S. W. (2008). Acta Cryst. E64, m718–m719. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Biswas, C., Drew, M. G. B. & Ghosh, A. (2008). Inorg. Chem. 47, 4513–4519. Web of Science CSD CrossRef PubMed CAS Google Scholar
Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Chen, Z., Morimoto, H., Matsunaga, S. & Shibasaki, M. (2008). J. Am. Chem. Soc. 130, 2170–2171. Web of Science CSD CrossRef PubMed CAS Google Scholar
Dapporto, P., Formica, M., Fusi, V., Giorgi, L., Micheloni, M., Paoli, P., Pontellini, R. & Rossi, P. (2001). Inorg. Chem. 40, 6186–6192. Web of Science CSD CrossRef PubMed CAS Google Scholar
Darensbourg, D. J. & Frantz, E. B. (2007). Inorg. Chem. 46, 5967–5978. Web of Science CSD CrossRef PubMed CAS Google Scholar
Habibi, M. H., Askari, E., Chantrapromma, S. & Fun, H.-K. (2007). Acta Cryst. E63, m2905–m2906. Web of Science CSD CrossRef IUCr Journals Google Scholar
Kawamoto, T., Nishiwaki, M., Tsunekawa, Y., Nozaki, K. & Konno, T. (2008). Inorg. Chem. 47, 3095–3104. Web of Science CSD CrossRef PubMed CAS Google Scholar
Lipscomb, W. N. & Sträter, N. (1996). Chem. Rev. 96, 2375–2434. CrossRef PubMed CAS Web of Science Google Scholar
Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Tomat, E., Cuesta, L., Lynch, V. M. & Sessler, J. L. (2007). Inorg. Chem. 46, 6224–6226. Web of Science CSD CrossRef PubMed CAS Google Scholar
Wu, J.-C., Liu, S.-X., Keene, T. D., Neels, A., Mereacre, V., Powell, A. K. & Decurtins, S. (2008). Inorg. Chem. 47, 3452–3459. Web of Science CSD CrossRef PubMed CAS Google Scholar
You, Z.-L. & Zhu, H.-L. (2006). Z. Anorg. Allg. Chem. 632, 140–146. Web of Science CSD CrossRef CAS Google Scholar
Yuan, M., Zhao, F., Zhang, W., WAng, Z.-M. & Gao, S. (2007). Inorg. Chem. 46, 11235–11242. Web of Science CSD CrossRef PubMed CAS Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 8| August 2008| Pages m1094-m1095

doi:10.1107/S1600536808023660

Open

access