(E)-N′-(2-Hydroxy­benzyl­idene)-3,4,5-trimethoxy­benzohydrazide

Wang, Y.-M.; Zhao, Z.-D.; Chen, Y.-X.; Bi, L.-W.

doi:10.1107/S1600536808006077

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 6| June 2008| Page o1009

doi:10.1107/S1600536808006077

Open

access

(E)-N′-(2-Hydroxybenzylidene)-3,4,5-trimethoxybenzohydrazide

Yu-Min Wang,^a Zhen-Dong Zhao,^a ^* Yu-Xiang Chen ^a and Liang-Wu Bi ^a

^aInstitute of Chemical Industry of Forest Products, Chinese Academy of Forestry, Nanjing 210042, People's Republic of China
^*Correspondence e-mail: minwangyu@126.com

(Received 30 January 2008; accepted 5 March 2008; online 7 May 2008)

The title compound, C₁₇H₁₈N₂O₅, was synthesized from 3,4,5-trimethoxybenzohydrazide and 2-hydroxybenzaldehyde. The dihedral angle between the planes of the two benzene rings is 29.9 (2)°. The crystal structure involves intramolecular O—H⋯N, and intermolecular N—H⋯O and C—H⋯O hydrogen bonds.

Related literature

For related literature, see: Yang et al. (1996 ); Nawar et al. (2000 ). Gardner et al. (1991 ); Labouta et al. (1989 ).

Experimental

Crystal data

C₁₇H₁₈N₂O₅
M_r = 330.33
Monoclinic, P 2₁ /c
a = 15.348 (12) Å
b = 13.330 (11) Å
c = 8.299 (7) Å
β = 99.854 (16)°
V = 1673 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 273 (2) K
0.10 × 0.06 × 0.04 mm

Data collection

Bruker APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.991, T_max = 0.995
8200 measured reflections
2952 independent reflections
1945 reflections with I > 2σ(I)
R_int = 0.048

Refinement

R[F² > 2σ(F²)] = 0.068
wR(F²) = 0.194
S = 1.00
2952 reflections
219 parameters
H-atom parameters constrained
Δρ_max = 0.59 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.82	1.94	2.670 (4)	147
N2—H2⋯O2ⁱ	0.86	2.00	2.826 (4)	161 (1)
C7—H7⋯O2ⁱ	0.93	2.48	3.240 (5)	139
Symmetry code: (i) $[x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 1997 ); cell refinement: SAINT (Bruker, 1997); 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 I, global. DOI: 10.1107/S1600536808006077/at2541sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808006077/at2541Isup2.hkl

checkCIF report

Comment top

3,4,5-Trimethoxybenzohydrazide and their deviatives show moderate fungicidal and anti-bacterial activities (Gardner et al.,1991). The antibacterial activity of formylhydrazines and formylhydrazones has been reported by Labouta et al. (1989). Many derivatives of formylhydrazines have interesting biological properties. So we synthesized the title compound (I) and report here its crystal structure.

The molecular structure of (I) is shown in Fig. 1, where the dash lines indicate N–H···O and O—H···N hydrogen bonds (Table 2). The atoms C7, N1, N2, C8 and O2 almost share a same plane for its delocalized structure. The dihedral angle between the planes of the two phenyl rings is 29.9 (217)°.

In the crystal structure, there is a intramolecular O—H···N hydrogen bond and two intermolecular N—H···O and C—H···O hydrogen bonds.

Related literature top

For related literature, see: Yang et al. (1996); Nawar et al. (2000). Gardner et al. (1991); Labouta et al. (1989).

Experimental top

An ethanol solution (50 ml) of 3,4,5-trimethoxybenzohydrazide (0.01 mol) and 2-hydroxybenzaldehyde (0.01 mol) was refluxed and stirred for 4 h. The mixture was cooled and the resulting solid product, (I), was collected by filtration. Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of a solution in THF.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); 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. A view of the molecular structure of the title compound, showing displacement ellipsoids at the 50% probability level.
	Fig. 2. The packing diagram for (I) showing three dimensional network formed via hydrogen bonding.

(E)-N'-(2-Hydroxybenzylidene)-3,4,5-trimethoxybenzohydrazide top

Crystal data top

C₁₇H₁₈N₂O₅	F(000) = 696
M_r = 330.33	D_x = 1.312 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2179 reflections
a = 15.348 (12) Å	θ = 2.7–22.9°
b = 13.330 (11) Å	µ = 0.10 mm⁻¹
c = 8.299 (7) Å	T = 273 K
β = 99.854 (16)°	Needle, colourless
V = 1673 (2) Å³	0.10 × 0.06 × 0.04 mm
Z = 4

Data collection top

Bruker APEX CCD area-detector diffractometer	2952 independent reflections
Radiation source: fine-focus sealed tube	1945 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.048
ϕ and ω scans	θ_max = 25.0°, θ_min = 1.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −14→18
T_min = 0.991, T_max = 0.995	k = −14→15
8200 measured reflections	l = −9→9

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)] = 0.068	H-atom parameters constrained
wR(F²) = 0.194	w = 1/[σ²(F_o²) + (0.09P)² + 1.3P] where P = (F_o² + 2F_c²)/3
S = 1.00	(Δ/σ)_max < 0.001
2952 reflections	Δρ_max = 0.59 e Å⁻³
219 parameters	Δρ_min = −0.26 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.009 (2)

Crystal data top

C₁₇H₁₈N₂O₅	V = 1673 (2) Å³
M_r = 330.33	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 15.348 (12) Å	µ = 0.10 mm⁻¹
b = 13.330 (11) Å	T = 273 K
c = 8.299 (7) Å	0.10 × 0.06 × 0.04 mm
β = 99.854 (16)°

Data collection top

Bruker APEX CCD area-detector diffractometer	2952 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1945 reflections with I > 2σ(I)
T_min = 0.991, T_max = 0.995	R_int = 0.048
8200 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.068	0 restraints
wR(F²) = 0.194	H-atom parameters constrained
S = 1.00	Δρ_max = 0.59 e Å⁻³
2952 reflections	Δρ_min = −0.26 e Å⁻³
219 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
O1	0.56784 (18)	0.60473 (18)	0.8299 (3)	0.0620 (7)
H1	0.6008	0.6424	0.7904	0.093*
O2	0.72936 (16)	0.85318 (16)	0.7297 (3)	0.0523 (7)
O3	0.81393 (18)	1.13644 (15)	0.3448 (4)	0.0684 (8)
O4	0.92560 (17)	1.04300 (17)	0.1799 (3)	0.0613 (8)
O5	0.96337 (16)	0.84707 (17)	0.2246 (3)	0.0586 (7)
N1	0.67460 (17)	0.66256 (18)	0.6249 (3)	0.0390 (6)
N2	0.72254 (17)	0.72742 (18)	0.5423 (3)	0.0412 (7)
H2	0.7367	0.7084	0.4512	0.049*
C1	0.5635 (2)	0.5152 (2)	0.7521 (4)	0.0445 (8)
C2	0.6102 (2)	0.4977 (2)	0.6245 (4)	0.0423 (8)
C3	0.6039 (2)	0.4020 (2)	0.5511 (4)	0.0541 (9)
H3	0.6344	0.3888	0.4658	0.065*
C4	0.5525 (3)	0.3270 (3)	0.6047 (5)	0.0643 (11)
H4	0.5497	0.2636	0.5574	0.077*
C5	0.5060 (3)	0.3479 (3)	0.7282 (5)	0.0651 (11)
H5	0.4708	0.2983	0.7629	0.078*
C6	0.5108 (3)	0.4403 (3)	0.8012 (4)	0.0602 (10)
H6	0.4785	0.4530	0.8843	0.072*
C7	0.6621 (2)	0.5750 (2)	0.5607 (4)	0.0421 (8)
H7	0.6874	0.5602	0.4693	0.051*
C8	0.7475 (2)	0.8195 (2)	0.6011 (4)	0.0379 (7)
C9	0.7992 (2)	0.8781 (2)	0.4960 (4)	0.0368 (7)
C10	0.7841 (2)	0.9807 (2)	0.4799 (4)	0.0441 (8)
H10	0.7461	1.0123	0.5400	0.053*
C11	0.8259 (2)	1.0356 (2)	0.3738 (4)	0.0461 (8)
C12	0.8839 (2)	0.9881 (2)	0.2853 (4)	0.0460 (8)
C13	0.9029 (2)	0.8862 (2)	0.3110 (4)	0.0428 (8)
C14	0.8592 (2)	0.8308 (2)	0.4139 (4)	0.0415 (8)
H14	0.8701	0.7624	0.4279	0.050*
C15	0.7580 (3)	1.1888 (3)	0.4353 (6)	0.0807 (14)
H15A	0.6995	1.1610	0.4119	0.121*
H15B	0.7560	1.2584	0.4053	0.121*
H15C	0.7806	1.1824	0.5501	0.121*
C16	0.8877 (3)	1.0316 (3)	0.0131 (6)	0.0787 (14)
H16A	0.8832	0.9615	−0.0138	0.118*
H16B	0.9243	1.0644	−0.0538	0.118*
H16C	0.8298	1.0611	−0.0062	0.118*
C17	1.0023 (3)	0.7532 (3)	0.2783 (5)	0.0656 (11)
H17A	1.0269	0.7572	0.3925	0.098*
H17B	1.0483	0.7375	0.2171	0.098*
H17C	0.9580	0.7017	0.2613	0.098*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.085 (2)	0.0474 (14)	0.0639 (17)	−0.0132 (13)	0.0429 (14)	−0.0088 (12)
O2	0.0821 (17)	0.0435 (13)	0.0395 (14)	0.0001 (11)	0.0339 (12)	−0.0002 (10)
O3	0.0843 (19)	0.0262 (12)	0.108 (2)	0.0009 (11)	0.0555 (17)	0.0053 (12)
O4	0.0757 (18)	0.0431 (13)	0.077 (2)	−0.0130 (12)	0.0470 (15)	0.0080 (12)
O5	0.0677 (16)	0.0472 (14)	0.0734 (18)	0.0114 (12)	0.0475 (14)	0.0096 (12)
N1	0.0488 (16)	0.0375 (14)	0.0352 (15)	−0.0023 (11)	0.0199 (12)	0.0062 (11)
N2	0.0614 (17)	0.0367 (14)	0.0326 (15)	−0.0051 (12)	0.0283 (13)	0.0024 (11)
C1	0.059 (2)	0.0382 (17)	0.0386 (19)	−0.0069 (15)	0.0148 (16)	−0.0011 (14)
C2	0.0508 (19)	0.0364 (16)	0.0417 (19)	−0.0023 (14)	0.0135 (15)	0.0034 (13)
C3	0.071 (2)	0.0403 (18)	0.054 (2)	−0.0005 (17)	0.0179 (18)	−0.0032 (16)
C4	0.087 (3)	0.0363 (18)	0.066 (3)	−0.0093 (19)	0.006 (2)	−0.0028 (17)
C5	0.086 (3)	0.051 (2)	0.056 (2)	−0.029 (2)	0.009 (2)	0.0073 (18)
C6	0.077 (3)	0.062 (2)	0.046 (2)	−0.0220 (19)	0.0245 (19)	0.0042 (17)
C7	0.053 (2)	0.0424 (18)	0.0355 (18)	0.0009 (14)	0.0201 (15)	0.0022 (14)
C8	0.0511 (19)	0.0370 (16)	0.0299 (17)	0.0027 (14)	0.0188 (14)	0.0058 (13)
C9	0.0451 (18)	0.0351 (16)	0.0339 (17)	−0.0007 (13)	0.0169 (14)	0.0011 (12)
C10	0.051 (2)	0.0367 (17)	0.051 (2)	−0.0017 (14)	0.0265 (16)	−0.0048 (14)
C11	0.057 (2)	0.0260 (15)	0.061 (2)	−0.0032 (14)	0.0271 (17)	0.0020 (14)
C12	0.053 (2)	0.0320 (16)	0.060 (2)	−0.0071 (14)	0.0305 (17)	0.0021 (14)
C13	0.0484 (19)	0.0369 (17)	0.050 (2)	0.0004 (14)	0.0271 (16)	0.0015 (14)
C14	0.053 (2)	0.0328 (16)	0.0429 (19)	0.0012 (14)	0.0213 (15)	0.0014 (13)
C15	0.093 (3)	0.0329 (19)	0.128 (4)	0.0065 (19)	0.053 (3)	−0.003 (2)
C16	0.090 (3)	0.079 (3)	0.077 (3)	−0.001 (2)	0.044 (3)	0.033 (2)
C17	0.065 (2)	0.069 (2)	0.070 (3)	0.024 (2)	0.031 (2)	0.009 (2)

Geometric parameters (Å, º) top

O1—C1	1.353 (4)	C5—H5	0.9300
O1—H1	0.8200	C6—H6	0.9300
O2—C8	1.233 (3)	C7—H7	0.9300
O3—C11	1.373 (4)	C8—C9	1.496 (4)
O3—C15	1.417 (4)	C9—C14	1.387 (4)
O4—C12	1.379 (4)	C9—C10	1.390 (4)
O4—C16	1.415 (5)	C10—C11	1.384 (4)
O5—C13	1.369 (3)	C10—H10	0.9300
O5—C17	1.424 (4)	C11—C12	1.398 (4)
N1—C7	1.284 (4)	C12—C13	1.399 (4)
N1—N2	1.389 (3)	C13—C14	1.386 (4)
N2—C8	1.351 (4)	C14—H14	0.9300
N2—H2	0.8600	C15—H15A	0.9600
C1—C6	1.389 (5)	C15—H15B	0.9600
C1—C2	1.396 (4)	C15—H15C	0.9600
C2—C3	1.410 (5)	C16—H16A	0.9600
C2—C7	1.456 (4)	C16—H16B	0.9600
C3—C4	1.393 (5)	C16—H16C	0.9600
C3—H3	0.9300	C17—H17A	0.9600
C4—C5	1.373 (5)	C17—H17B	0.9600
C4—H4	0.9300	C17—H17C	0.9600
C5—C6	1.369 (5)

C1—O1—H1	109.5	C10—C9—C8	118.3 (3)
C11—O3—C15	117.7 (3)	C11—C10—C9	119.6 (3)
C12—O4—C16	113.9 (3)	C11—C10—H10	120.2
C13—O5—C17	117.1 (3)	C9—C10—H10	120.2
C7—N1—N2	114.5 (2)	O3—C11—C10	124.5 (3)
C8—N2—N1	121.9 (2)	O3—C11—C12	115.4 (3)
C8—N2—H2	119.1	C10—C11—C12	120.1 (3)
N1—N2—H2	119.1	O4—C12—C11	120.0 (3)
O1—C1—C6	118.5 (3)	O4—C12—C13	120.3 (3)
O1—C1—C2	121.3 (3)	C11—C12—C13	119.6 (3)
C6—C1—C2	120.2 (3)	O5—C13—C14	124.3 (3)
C1—C2—C3	118.2 (3)	O5—C13—C12	115.6 (3)
C1—C2—C7	122.8 (3)	C14—C13—C12	120.1 (3)
C3—C2—C7	118.9 (3)	C13—C14—C9	119.5 (3)
C4—C3—C2	120.8 (3)	C13—C14—H14	120.2
C4—C3—H3	119.6	C9—C14—H14	120.2
C2—C3—H3	119.6	O3—C15—H15A	109.5
C5—C4—C3	119.2 (3)	O3—C15—H15B	109.5
C5—C4—H4	120.4	H15A—C15—H15B	109.5
C3—C4—H4	120.4	O3—C15—H15C	109.5
C6—C5—C4	121.2 (3)	H15A—C15—H15C	109.5
C6—C5—H5	119.4	H15B—C15—H15C	109.5
C4—C5—H5	119.4	O4—C16—H16A	109.5
C5—C6—C1	120.4 (3)	O4—C16—H16B	109.5
C5—C6—H6	119.8	H16A—C16—H16B	109.5
C1—C6—H6	119.8	O4—C16—H16C	109.5
N1—C7—C2	122.9 (3)	H16A—C16—H16C	109.5
N1—C7—H7	118.5	H16B—C16—H16C	109.5
C2—C7—H7	118.5	O5—C17—H17A	109.5
O2—C8—N2	123.5 (3)	O5—C17—H17B	109.5
O2—C8—C9	122.3 (3)	H17A—C17—H17B	109.5
N2—C8—C9	114.2 (2)	O5—C17—H17C	109.5
C14—C9—C10	120.9 (3)	H17A—C17—H17C	109.5
C14—C9—C8	120.8 (3)	H17B—C17—H17C	109.5

C7—N1—N2—C8	−174.6 (3)	C8—C9—C10—C11	−175.1 (3)
O1—C1—C2—C3	178.8 (3)	C15—O3—C11—C10	3.0 (6)
C6—C1—C2—C3	−1.5 (5)	C15—O3—C11—C12	−178.0 (3)
O1—C1—C2—C7	−3.6 (5)	C9—C10—C11—O3	178.1 (3)
C6—C1—C2—C7	176.1 (3)	C9—C10—C11—C12	−0.9 (5)
C1—C2—C3—C4	−0.1 (5)	C16—O4—C12—C11	−102.2 (4)
C7—C2—C3—C4	−177.8 (3)	C16—O4—C12—C13	81.3 (4)
C2—C3—C4—C5	1.5 (6)	O3—C11—C12—O4	1.1 (5)
C3—C4—C5—C6	−1.2 (6)	C10—C11—C12—O4	−179.9 (3)
C4—C5—C6—C1	−0.4 (6)	O3—C11—C12—C13	177.6 (3)
O1—C1—C6—C5	−178.5 (4)	C10—C11—C12—C13	−3.4 (5)
C2—C1—C6—C5	1.8 (6)	C17—O5—C13—C14	−18.9 (5)
N2—N1—C7—C2	−177.2 (3)	C17—O5—C13—C12	163.4 (3)
C1—C2—C7—N1	5.6 (5)	O4—C12—C13—O5	−0.7 (5)
C3—C2—C7—N1	−176.8 (3)	C11—C12—C13—O5	−177.1 (3)
N1—N2—C8—O2	−0.7 (5)	O4—C12—C13—C14	−178.4 (3)
N1—N2—C8—C9	179.5 (2)	C11—C12—C13—C14	5.1 (5)
O2—C8—C9—C14	143.6 (3)	O5—C13—C14—C9	179.9 (3)
N2—C8—C9—C14	−36.7 (4)	C12—C13—C14—C9	−2.5 (5)
O2—C8—C9—C10	−37.9 (4)	C10—C9—C14—C13	−1.8 (5)
N2—C8—C9—C10	141.9 (3)	C8—C9—C14—C13	176.8 (3)
C14—C9—C10—C11	3.5 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.94	2.670 (4)	147
N2—H2···O2ⁱ	0.86	2.00	2.826 (4)	161 (1)
C7—H7···O2ⁱ	0.93	2.48	3.240 (5)	139

Symmetry code: (i) x, −y+3/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₇H₁₈N₂O₅
M_r	330.33
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	273
a, b, c (Å)	15.348 (12), 13.330 (11), 8.299 (7)
β (°)	99.854 (16)
V (Å³)	1673 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.10 × 0.06 × 0.04

Data collection
Diffractometer	Bruker APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.991, 0.995
No. of measured, independent and observed [I > 2σ(I)] reflections	8200, 2952, 1945
R_int	0.048
(sin θ/λ)_max (Å⁻¹)	0.596

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.068, 0.194, 1.00
No. of reflections	2952
No. of parameters	219
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.59, −0.26

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.94	2.670 (4)	147
N2—H2···O2ⁱ	0.86	2.00	2.826 (4)	161 (1)
C7—H7···O2ⁱ	0.93	2.48	3.240 (5)	139

Symmetry code: (i) x, −y+3/2, z−1/2.

Acknowledgements

This work was supported by the Natural Science Fund of Jiangsu Province (No. BK2006012).

References

Bruker (1997). SAINT and SMART. Bruker AXS, Inc., Madison, Wisconsin, USA. Google Scholar
Gardner, T. S., Weins, R. & Lee, J. (1991). J Org Chem. 26, 1514–1530. CrossRef Web of Science Google Scholar
Labouta, I. M., Hassan, A. M., Aboulwafa, O. M. & Kader, O. (1989). Monatsh. Chem. 120, 571–574. CrossRef CAS Web of Science Google Scholar
Nawar, N. & Hosny, N. M. (2000). Transition Met. Chem. 25, 1–8. Web of Science CrossRef CAS Google Scholar
Sheldrick, G. M. (1996). 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
Yang, Z. Y., Yang, R. D. & Yu, K. B. (1996). Polyhedron, 15, 3749–3753. CSD CrossRef CAS Web of Science Google Scholar