{5,5′-Dimeth­oxy-2,2′-[2,2-dimethyl­propane-1,3-diylbis(nitrilo­methanylyl­idene)]diphenolato}palladium(II)

Che Soh, S.K.; Shamsuddin, M.; Rosli, M.M.; Fun, H.-K.

doi:10.1107/S1600536812013128

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 4| April 2012| Pages m514-m515

doi:10.1107/S1600536812013128

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{5,5′-Dimethoxy-2,2′-[2,2-dimethylpropane-1,3-diylbis(nitrilomethanylylidene)]diphenolato}palladium(II)

Siti Kamilah Che Soh,^a,^b Mustaffa Shamsuddin,^a,^c Mohd Mustaqim Rosli ^d and Hoong-Kun Fun ^d ^*‡

^aDepartment of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia, ^bDepartment of Chemical Sciences, Faculty of Science and Technology, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia, ^cIbnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia, and ^dX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: hkfun@usm.my

(Received 16 March 2012; accepted 26 March 2012; online 31 March 2012)

In the title compound, [Pd(C₂₁H₂₄N₂O₄)], the complete molecule is generated by crystallographic mirror symmetry with the Pd and three C atoms lying on the mirror plane. The Pd—O and Pd—N distances are 1.9932 (6) and 2.0029 (7) Å, respectively. The dihedral angle between two benzene rings of the ligand is 79.21 (4)°. In the crystal, C—H⋯O hydrogen bonds link the molecules into layers parallel to the ab plane. These planes are further connected by C—H⋯O interactions, forming a three-dimensional network.

Related literature

For related structures, see: Wan Nazihah Wan Ibrahim et al. (2008 ); Montazerozohori et al. (2009 ). For background to applications of palladium(II) complexes, see: Gupta et al. (2009 ); Lu et al. (2010 ); He & Cai (2011 ); Garoufis et al. (2008 ); Kumar et al. (2009 ); Islam et al. (2011 ). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ).

Experimental

Crystal data

[Pd(C₂₁H₂₄N₂O₄)]
M_r = 474.82
Orthorhombic, P n m a
a = 11.5470 (4) Å
b = 20.9656 (7) Å
c = 7.8730 (3) Å
V = 1905.97 (12) Å³
Z = 4
Mo Kα radiation
μ = 1.00 mm⁻¹
T = 100 K
0.27 × 0.24 × 0.18 mm

Data collection

Bruker APEX DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.773, T_max = 0.839
30756 measured reflections
4296 independent reflections
4134 reflections with I > 2σ(I)
R_int = 0.020

Refinement

R[F² > 2σ(F²)] = 0.016
wR(F²) = 0.043
S = 1.13
4296 reflections
134 parameters
H-atom parameters constrained
Δρ_max = 0.50 e Å⁻³
Δρ_min = −0.62 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8A⋯O1ⁱ	0.99	2.37	3.3355 (10)	166
C12—H12A⋯O2ⁱⁱ	0.98	2.58	3.3719 (12)	138
Symmetry codes: (i) $[x+{\script{1\over 2}}, y, -z+{\script{1\over 2}}]$ ; (ii) -x, -y+1, -z.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812013128/kj2196sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812013128/kj2196Isup2.hkl

checkCIF report

Comment top

Palladium(II)-Schiff base complexes have found extensive application in catalysis (Gupta et al., 2009; Lu et al., 2010; He and Cai 2011) and biological activities (Garoufis et al., 2008). In particular, they are efficient and powerful phosphine-free catalysts for the formation of new C-C bonds in organic syntheses (Kumar et al., 2009; Islam et al., 2011). The title square-planar complex is analogous to the previously reported complex {2,2'-[(2,2 dimethylpropane-1,3-diyl)-bis(nitrilomethylidyne)]diphenolato}-palladium(II) ethanol hemisolvate (Wan Nazihah Wan Ibrahim et al., 2008) in terms of geometry around the central palladium atom.

In the title compound, the complete molecule (Fig. 1) is generated by crystallographic mirror symmetry with the Pd1, C9, C10 and C11 atoms lying on the mirror plane. All parameters are within normal ranges and comparable with the related structures (Wan Nazihah Wan Ibrahim et al., 2008). The Pd—O and Pd—N distances are 1.9932 (6)Å and 2.0029 (7)Å respectively. The dihedral angle between two benzene ring (C1-C6 & C1A-C6A) is 79.21 (4)°.

In the crystal packing, the molecules are linked by C8—H8A···O1ⁱ intermolecular into layers parallel to the ab-plane. These planes are further connected by C12—H12A···O2ⁱⁱ to form a three-dimensional network (Table 1 & Fig. 2).

Related literature top

For related structures, see: Wan Nazihah Wan Ibrahim et al. (2008). For background to applications of palladium(II) complexes, see: Gupta et al. (2009); Lu et al. (2010); He & Cai (2011); Garoufis et al. (2008); Kumar et al. (2009); Islam et al. (2011).

For related literature, see: Cosier & Glazer (1986); Montazerozohori et al. (2009).

Experimental top

The complex obtained was synthesized by dissolving the N,N'-bis(4-methoxy-salicylidene)-2,2-dimethylpropane-1,3-diamine ligand (0.2000 g, 0.54 mmol) in dry acetonitrile (10 ml) in a three necked round bottom flask. Palladium(II) acetate (0.1212 g, 0.54 mmol) which was dissolved separately in dry acetonitrile (10 ml) was then added into the flask containing the ligand solution. The mixture was stirred and refluxed under N₂ gas atmosphere for 3 h. The yellow solid formed was separated by vacuum filtration, washed with cold acetonitrile and allowed to dry in vacuo. The solid product was then recrystallized from a mixture of dicholoromethane/methanol (1:1 v/v). Slow evaporation of the solvent at room temperature over several days gave yellow crystals (yield: 78%). Melting point: 596 K-598 K.

Structure description top

For related literature, see: Cosier & Glazer (1986); Montazerozohori et al. (2009).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure, showing 50% probability displacement ellipsoids. Hydrogen atoms are shown as spheres of arbitrary radius.
	Fig. 2. The crystal packing of (I). Dashed lines indicate hydrogen bonds. H atoms not involved in the hydrogen bond interactions have been omitted for clarity.

{5,5'-Dimethoxy-2,2'-[2,2-dimethylpropane-1,3- diylbis(nitrilomethanylylidene)]diphenolato}palladium(II) top

Crystal data top

[Pd(C₂₁H₂₄N₂O₄)]	F(000) = 968
M_r = 474.82	D_x = 1.655 Mg m⁻³
Orthorhombic, Pnma	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2n	Cell parameters from 9824 reflections
a = 11.5470 (4) Å	θ = 3.3–35.1°
b = 20.9656 (7) Å	µ = 1.00 mm⁻¹
c = 7.8730 (3) Å	T = 100 K
V = 1905.97 (12) Å³	Block, yellow
Z = 4	0.27 × 0.24 × 0.18 mm

Data collection top

Bruker APEX DUO CCD area-detector diffractometer	4296 independent reflections
Radiation source: fine-focus sealed tube	4134 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.020
φ and ω scans	θ_max = 35.1°, θ_min = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −18→18
T_min = 0.773, T_max = 0.839	k = −33→33
30756 measured reflections	l = −8→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)] = 0.016	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.043	H-atom parameters constrained
S = 1.13	w = 1/[σ²(F_o²) + (0.0183P)² + 0.777P] where P = (F_o² + 2F_c²)/3
4296 reflections	(Δ/σ)_max = 0.003
134 parameters	Δρ_max = 0.50 e Å⁻³
0 restraints	Δρ_min = −0.62 e Å⁻³

Crystal data top

[Pd(C₂₁H₂₄N₂O₄)]	V = 1905.97 (12) Å³
M_r = 474.82	Z = 4
Orthorhombic, Pnma	Mo Kα radiation
a = 11.5470 (4) Å	µ = 1.00 mm⁻¹
b = 20.9656 (7) Å	T = 100 K
c = 7.8730 (3) Å	0.27 × 0.24 × 0.18 mm

Data collection top

Bruker APEX DUO CCD area-detector diffractometer	4296 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	4134 reflections with I > 2σ(I)
T_min = 0.773, T_max = 0.839	R_int = 0.020
30756 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.016	0 restraints
wR(F²) = 0.043	H-atom parameters constrained
S = 1.13	Δρ_max = 0.50 e Å⁻³
4296 reflections	Δρ_min = −0.62 e Å⁻³
134 parameters

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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
Pd1	0.535617 (6)	0.2500	0.088830 (10)	0.00982 (2)
O1	0.42276 (5)	0.31425 (3)	0.17501 (8)	0.01411 (10)
O2	0.12833 (5)	0.45403 (3)	−0.02329 (9)	0.01723 (11)
N1	0.63494 (6)	0.31998 (3)	−0.00483 (9)	0.01240 (11)
C1	0.39331 (7)	0.36205 (4)	0.07712 (9)	0.01203 (11)
C2	0.27757 (7)	0.38427 (4)	0.08646 (10)	0.01310 (12)
H2A	0.2251	0.3651	0.1642	0.016*
C3	0.24037 (7)	0.43360 (4)	−0.01673 (10)	0.01370 (12)
C4	0.31792 (7)	0.46562 (4)	−0.12613 (11)	0.01645 (13)
H4A	0.2924	0.5004	−0.1939	0.020*
C5	0.43136 (7)	0.44543 (4)	−0.13264 (11)	0.01566 (13)
H5A	0.4844	0.4675	−0.2038	0.019*
C6	0.47127 (6)	0.39285 (4)	−0.03651 (10)	0.01282 (12)
C7	0.59049 (7)	0.37365 (4)	−0.05364 (10)	0.01349 (12)
H7A	0.6415	0.4033	−0.1059	0.016*
C8	0.76027 (6)	0.31049 (4)	−0.02515 (11)	0.01447 (13)
H8A	0.7964	0.3083	0.0887	0.017*
H8B	0.7932	0.3479	−0.0847	0.017*
C9	0.79183 (9)	0.2500	−0.12444 (14)	0.01195 (16)
C10	0.73574 (10)	0.2500	−0.29972 (15)	0.01630 (19)
H10A	0.7594	0.2874	−0.3609	0.024*
H10B	0.6530	0.2500	−0.2876	0.024*
C11	0.92430 (10)	0.2500	−0.14109 (16)	0.01623 (19)
H11A	0.9487	0.2874	−0.2017	0.024*
H11B	0.9584	0.2500	−0.0299	0.024*
C12	0.04407 (7)	0.41728 (5)	0.06862 (13)	0.01862 (15)
H12A	−0.0332	0.4353	0.0496	0.028*
H12B	0.0622	0.4185	0.1902	0.028*
H12C	0.0457	0.3730	0.0288	0.028*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pd1	0.00822 (4)	0.01192 (4)	0.00933 (4)	0.000	0.00093 (2)	0.000
O1	0.0140 (2)	0.0151 (2)	0.0133 (2)	0.00348 (18)	0.00348 (19)	0.00199 (19)
O2	0.0125 (2)	0.0189 (3)	0.0203 (3)	0.0032 (2)	0.0008 (2)	0.0040 (2)
N1	0.0097 (2)	0.0144 (3)	0.0131 (3)	−0.0006 (2)	0.0015 (2)	−0.0015 (2)
C1	0.0122 (3)	0.0127 (3)	0.0112 (3)	0.0005 (2)	0.0008 (2)	−0.0011 (2)
C2	0.0122 (3)	0.0141 (3)	0.0130 (3)	0.0013 (2)	0.0015 (2)	0.0002 (2)
C3	0.0129 (3)	0.0144 (3)	0.0137 (3)	0.0016 (2)	−0.0001 (2)	−0.0007 (2)
C4	0.0165 (3)	0.0157 (3)	0.0172 (3)	0.0016 (2)	0.0013 (3)	0.0036 (3)
C5	0.0163 (3)	0.0145 (3)	0.0162 (3)	0.0001 (2)	0.0027 (3)	0.0021 (2)
C6	0.0121 (3)	0.0128 (3)	0.0135 (3)	0.0000 (2)	0.0017 (2)	0.0001 (2)
C7	0.0126 (3)	0.0138 (3)	0.0140 (3)	−0.0013 (2)	0.0020 (2)	−0.0007 (2)
C8	0.0089 (3)	0.0173 (3)	0.0171 (3)	−0.0012 (2)	0.0013 (2)	−0.0035 (3)
C9	0.0088 (4)	0.0152 (4)	0.0119 (4)	0.000	0.0012 (3)	0.000
C10	0.0142 (4)	0.0232 (5)	0.0115 (4)	0.000	0.0000 (3)	0.000
C11	0.0097 (4)	0.0200 (5)	0.0189 (5)	0.000	0.0025 (4)	0.000
C12	0.0132 (3)	0.0195 (4)	0.0232 (4)	0.0009 (3)	0.0012 (3)	0.0018 (3)

Geometric parameters (Å, º) top

Pd1—O1ⁱ	1.9932 (6)	C5—H5A	0.9500
Pd1—O1	1.9932 (6)	C6—C7	1.4406 (11)
Pd1—N1ⁱ	2.0029 (7)	C7—H7A	0.9500
Pd1—N1	2.0029 (7)	C8—C9	1.5337 (10)
O1—C1	1.3092 (9)	C8—H8A	0.9900
O2—C3	1.3637 (10)	C8—H8B	0.9900
O2—C12	1.4366 (11)	C9—C10	1.5244 (16)
N1—C7	1.2951 (10)	C9—C8ⁱ	1.5336 (10)
N1—C8	1.4695 (10)	C9—C11	1.5353 (15)
C1—C2	1.4172 (11)	C10—H10A	0.9600
C1—C6	1.4239 (11)	C10—H10B	0.9600
C2—C3	1.3835 (11)	C11—H11A	0.9599
C2—H2A	0.9500	C11—H11B	0.9600
C3—C4	1.4122 (12)	C12—H12A	0.9800
C4—C5	1.3776 (12)	C12—H12B	0.9800
C4—H4A	0.9500	C12—H12C	0.9800
C5—C6	1.4144 (11)

O1ⁱ—Pd1—O1	85.03 (3)	C1—C6—C7	122.43 (7)
O1ⁱ—Pd1—N1ⁱ	90.27 (3)	N1—C7—C6	126.41 (7)
O1—Pd1—N1ⁱ	174.10 (3)	N1—C7—H7A	116.8
O1ⁱ—Pd1—N1	174.10 (3)	C6—C7—H7A	116.8
O1—Pd1—N1	90.27 (3)	N1—C8—C9	113.67 (7)
N1ⁱ—Pd1—N1	94.20 (4)	N1—C8—H8A	108.8
C1—O1—Pd1	119.13 (5)	C9—C8—H8A	108.8
C3—O2—C12	117.06 (7)	N1—C8—H8B	108.8
C7—N1—C8	118.40 (7)	C9—C8—H8B	108.8
C7—N1—Pd1	121.25 (5)	H8A—C8—H8B	107.7
C8—N1—Pd1	120.32 (5)	C10—C9—C8ⁱ	111.13 (6)
O1—C1—C2	117.78 (7)	C10—C9—C8	111.13 (6)
O1—C1—C6	123.55 (7)	C8ⁱ—C9—C8	111.56 (9)
C2—C1—C6	118.67 (7)	C10—C9—C11	110.24 (9)
C3—C2—C1	120.53 (7)	C8ⁱ—C9—C11	106.28 (6)
C3—C2—H2A	119.7	C8—C9—C11	106.28 (6)
C1—C2—H2A	119.7	C9—C10—H10A	109.5
O2—C3—C2	123.47 (7)	C9—C10—H10B	109.5
O2—C3—C4	115.41 (7)	H10A—C10—H10B	109.5
C2—C3—C4	121.11 (7)	C9—C11—H11A	109.6
C5—C4—C3	118.66 (7)	C9—C11—H11B	109.3
C5—C4—H4A	120.7	H11A—C11—H11B	109.5
C3—C4—H4A	120.7	O2—C12—H12A	109.5
C4—C5—C6	121.96 (7)	O2—C12—H12B	109.5
C4—C5—H5A	119.0	H12A—C12—H12B	109.5
C6—C5—H5A	119.0	O2—C12—H12C	109.5
C5—C6—C1	118.93 (7)	H12A—C12—H12C	109.5
C5—C6—C7	118.62 (7)	H12B—C12—H12C	109.5

O1ⁱ—Pd1—O1—C1	−132.69 (5)	C3—C4—C5—C6	1.59 (13)
N1—Pd1—O1—C1	43.75 (6)	C4—C5—C6—C1	−3.42 (13)
O1—Pd1—N1—C7	−29.00 (6)	C4—C5—C6—C7	178.41 (8)
N1ⁱ—Pd1—N1—C7	147.14 (5)	O1—C1—C6—C5	−177.99 (7)
O1—Pd1—N1—C8	153.13 (6)	C2—C1—C6—C5	1.59 (11)
N1ⁱ—Pd1—N1—C8	−30.72 (7)	O1—C1—C6—C7	0.11 (12)
Pd1—O1—C1—C2	144.53 (6)	C2—C1—C6—C7	179.69 (7)
Pd1—O1—C1—C6	−35.88 (10)	C8—N1—C7—C6	−176.76 (8)
O1—C1—C2—C3	−178.41 (7)	Pd1—N1—C7—C6	5.33 (11)
C6—C1—C2—C3	1.98 (11)	C5—C6—C7—N1	−164.51 (8)
C12—O2—C3—C2	−6.96 (12)	C1—C6—C7—N1	17.38 (13)
C12—O2—C3—C4	171.91 (8)	C7—N1—C8—C9	−125.73 (8)
C1—C2—C3—O2	174.91 (7)	Pd1—N1—C8—C9	52.19 (9)
C1—C2—C3—C4	−3.90 (12)	N1—C8—C9—C10	57.06 (10)
O2—C3—C4—C5	−176.79 (8)	N1—C8—C9—C8ⁱ	−67.56 (11)
C2—C3—C4—C5	2.11 (13)	N1—C8—C9—C11	177.01 (7)

Symmetry code: (i) x, −y+1/2, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···O1ⁱⁱ	0.99	2.37	3.3355 (10)	166
C12—H12A···O2ⁱⁱⁱ	0.98	2.58	3.3719 (12)	138

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

Experimental details

Crystal data
Chemical formula	[Pd(C₂₁H₂₄N₂O₄)]
M_r	474.82
Crystal system, space group	Orthorhombic, Pnma
Temperature (K)	100
a, b, c (Å)	11.5470 (4), 20.9656 (7), 7.8730 (3)
V (Å³)	1905.97 (12)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.00
Crystal size (mm)	0.27 × 0.24 × 0.18

Data collection
Diffractometer	Bruker APEX DUO CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.773, 0.839
No. of measured, independent and observed [I > 2σ(I)] reflections	30756, 4296, 4134
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.809

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.016, 0.043, 1.13
No. of reflections	4296
No. of parameters	134
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.50, −0.62

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···O1ⁱ	0.9900	2.3700	3.3355 (10)	166.00
C12—H12A···O2ⁱⁱ	0.9800	2.5800	3.3719 (12)	138.00

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

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

The Ministry of Higher Education, Malaysia, and Universiti Teknologi Malaysia are acknowledged for financial support through the Research University Grant Vote No. 00H13. SKCS wishes to thank Universiti Malaysia Terengganu for a scholarship and study leave.

References

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