2,2′-{1,1′-[Pentane-1,5-diylbis(oxy­nitrilo)]diethylidyne}di-1-naphthol

Sun, Y.-X.; Wu, J.-C.; Dong, W.-K.; Gong, S.; Tong, J.-F.

doi:10.1107/S1600536809016584

organic compounds

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ISSN: 2056-9890

Volume 65| Part 6| June 2009| Page o1238

doi:10.1107/S1600536809016584

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2,2′-{1,1′-[Pentane-1,5-diylbis(oxynitrilo)]diethylidyne}di-1-naphthol

Yin-Xia Sun,^a Jian-Chao Wu,^a Wen-Kui Dong,^a ^* Shang-sheng Gong ^a and Jun-Feng Tong ^a

^aSchool of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China
^*Correspondence e-mail: dongwk@mail.lzjtu.cn

(Received 30 April 2009; accepted 4 May 2009; online 14 May 2009)

The title compound, C₂₉H₃₀N₂O₄, adopts a distorted Z configuration with respect to the oxime group, which is almost coplanar with the adjacent naphthalene ring [dihedral angle = 4.11 (2)°]. There is one half-molecule in the asymmetric unit, with a crystallographic twofold rotation axis passing through the central C atom of the –CH=N—O-(CH)₅—O—N=CH– bridge. Within the molecule, the dihedral angle formed by the two naphthalene rings is 79.08 (3)°, and there are two intramolecular O—H⋯N hydrogen bonds.

Related literature

The condensation of primary amines with active carbonyl compounds can yield Schiff bases, see: Atwood & Harvey (2001 ); Casellato & Vigato (1977 ). For related structures, see: Dong et al. (2008a ,b ,c , 2009 ); Shi et al. (2007 ); Yeap et al. (2008 ).

Experimental

Crystal data

C₂₉H₃₀N₂O₄
M_r = 470.55
Monoclinic, C 2
a = 14.0683 (12) Å
b = 4.5659 (7) Å
c = 19.048 (2) Å
β = 97.321 (1)°
V = 1213.6 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 298 K
0.49 × 0.45 × 0.21 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.959, T_max = 0.982
3170 measured reflections
1218 independent reflections
814 reflections with I > 2σ(I)
R_int = 0.034

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.111
S = 1.02
1218 reflections
159 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.11 e Å⁻³
Δρ_min = −0.13 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯N1	0.82	1.83	2.552 (3)	145

Data collection: SMART (Siemens, 1996 ); cell refinement: SAINT (Siemens, 1996); 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/S1600536809016584/at2776sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809016584/at2776Isup2.hkl

checkCIF report

Comment top

The condensation of primary amines with active carbonyl compounds can yield Schiff bases (Casellato & Vigato, 1977; Atwood & Harvey, 2001) that are still now regarded as one of the most potential group of chelators for facile preparations of metallo-organic hybrid materials (Yeap et al., 2008). Many Schiff base complexes have been structurally characterized, but at present, a new class of salen-type bisoxime compounds have been synthesized by using an O-alkyloxime unit (–CH═N—O-(CH)_n—O—N═CH–) instead of the (–CH═N-(CH)_n—N═CH–) group (Dong et al., 2008a,b), the large electronegativity of O atoms is expected to affect strongly the electronic properties of N₂O₂ coordination sphere. Herein, we report on the synthesis and crystal structure of 2,2'-{1,1'-[pentane-1,5-diylbis(oxynitrilo)]diethylidyne}dinaphthol, (I), (Fig. 1).

The single-crystal structure of the title compound (I) is built up by only the C₂₉H₃₀N₂O₄ molecule, in which all bond lengths are in normal ranges. It adopts a distorted Z configuration with respect to the bisoxime group which is coplanar with the adjacent naphthalene ring (Dong et al., 2008c). The structure of (I) reveals the C1, C2, C3, C2# and C1# atoms in the (–CH═N—O-(CH)₅—O—N═CH–) bridge lying on a plane. The dihedral angle formed by the two naphthalene rings in each molecule of the title compound is about 79.08°. Within each half of the molecule, the dihedral angle formed by the plane of the (–(CH)₅–) bridge and the adjacent naphthalene ring is about 62.74°. There are two intramolecular hydrogen bonds, O2—H2···N1 (Table 1), indicating a strong hydrogen-bonding interaction.

Related literature top

The condensation of primary amines with active carbonyl compounds can yield Schiff bases, see: Atwood & Harvey (2001); Casellato & Vigato (1977). For related structures, see: Dong et al. (2008a,b,c, 2009); Shi et al. (2007); Yeap et al. (2008).

Experimental top

2,2'-{1,1'-[Pentane-1,5-diylbis(oxynitrilo)]diethylidyne}dinaphthol was synthesized according to an analogous method reported earlier (Shi et al., 2007; Dong et al., 2009). To an ethanol solution (5 ml) of 2-acetyl-1-naphthol (374.7 mg, 2.02 mmol) was added dropwise an ethanol solution (3 ml) of 1,5-bis(aminooxy)pentane (133.5 mg, 0.94 mmol). The mixture solution was stirred at 328–333 K for 70 h. After cooling to room temperature, the precipitate was filtered off, and washed successively three times with ethanol. The product was dried in vacuo and purified by recrystallization from ethanol to yield 367.5 mg (yield, 83.1%) of solid; m.p. 394–396 K. Colourless needle-like single crystals suitable for X-ray diffraction studies were obtained by slow evaporation from a solution of chloroform/methanol (1:1) of 2,2'-{1,1'-[pentane-1,5-diylbis(oxynitrilo)]diethylidyne}dinaphthol at room temperature for about three weeks. Analysis calculated for C₂₉H₃₀N₂O₄: C 74.02, H 6.43, N 5.99 (%); Found: C 74.05, H 6.39, N 6.07(%).

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SMART (Siemens, 1996); data reduction: SAINT (Siemens, 1996); 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 with atom-numbering scheme [symmetry code: (#1) - x, y, -z]. Displacement ellipsoids for non-hydrogen atoms are drawn at the 30% probability level.

2,2'-{1,1'-[Pentane-1,5-diylbis(oxynitrilo)]diethylidyne}di-1-naphthol top

Crystal data top

C₂₉H₃₀N₂O₄	F(000) = 500
M_r = 470.55	D_x = 1.288 Mg m⁻³
Monoclinic, C2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2y	Cell parameters from 907 reflections
a = 14.0683 (12) Å	θ = 2.9–22.5°
b = 4.5659 (7) Å	µ = 0.09 mm⁻¹
c = 19.048 (2) Å	T = 298 K
β = 97.321 (1)°	Block-like, yellow
V = 1213.6 (2) Å³	0.49 × 0.45 × 0.21 mm
Z = 2

Data collection top

Bruker SMART CCD area-detector diffractometer	1218 independent reflections
Radiation source: fine-focus sealed tube	814 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.034
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −16→9
T_min = 0.959, T_max = 0.982	k = −5→5
3170 measured reflections	l = −21→22

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)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.111	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.057P)²] where P = (F_o² + 2F_c²)/3
1218 reflections	(Δ/σ)_max < 0.001
159 parameters	Δρ_max = 0.11 e Å⁻³
1 restraint	Δρ_min = −0.13 e Å⁻³

Crystal data top

C₂₉H₃₀N₂O₄	V = 1213.6 (2) Å³
M_r = 470.55	Z = 2
Monoclinic, C2	Mo Kα radiation
a = 14.0683 (12) Å	µ = 0.09 mm⁻¹
b = 4.5659 (7) Å	T = 298 K
c = 19.048 (2) Å	0.49 × 0.45 × 0.21 mm
β = 97.321 (1)°

Data collection top

Bruker SMART CCD area-detector diffractometer	1218 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	814 reflections with I > 2σ(I)
T_min = 0.959, T_max = 0.982	R_int = 0.034
3170 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	1 restraint
wR(F²) = 0.111	H-atom parameters constrained
S = 1.02	Δρ_max = 0.11 e Å⁻³
1218 reflections	Δρ_min = −0.13 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	Occ. (<1)
N1	0.2185 (2)	−0.0996 (7)	0.16024 (12)	0.0654 (8)
O1	0.24369 (16)	−0.2609 (7)	0.10176 (10)	0.0807 (7)
O2	0.09872 (13)	0.1007 (6)	0.23812 (10)	0.0734 (7)
H2	0.1157	0.0056	0.2054	0.110*
C1	0.1626 (2)	−0.4239 (10)	0.07147 (17)	0.0768 (10)
H1A	0.1376	−0.5343	0.1086	0.092*
H1B	0.1829	−0.5633	0.0379	0.092*
C2	0.0834 (2)	−0.2382 (10)	0.03427 (15)	0.0700 (9)
H2A	0.1085	−0.1218	−0.0018	0.084*
H2B	0.0606	−0.1049	0.0681	0.084*
C3	0.0000	−0.4226 (13)	0.0000	0.0661 (13)
H3A	−0.0223	−0.5478	0.0357	0.079*	0.50
H3B	0.0223	−0.5478	−0.0357	0.079*	0.50
C4	0.3854 (2)	0.0583 (12)	0.16832 (16)	0.0890 (13)
H4A	0.3863	−0.0668	0.1279	0.134*
H4B	0.4321	−0.0087	0.2061	0.134*
H4C	0.4004	0.2552	0.1559	0.134*
C5	0.2876 (2)	0.0510 (9)	0.19192 (15)	0.0621 (9)
C6	0.1752 (2)	0.2479 (9)	0.27207 (14)	0.0543 (8)
C7	0.2658 (2)	0.2281 (8)	0.25198 (13)	0.0527 (8)
C8	0.3400 (2)	0.3899 (9)	0.29307 (16)	0.0673 (10)
H8	0.4022	0.3771	0.2816	0.081*
C9	0.3230 (2)	0.5610 (10)	0.34806 (16)	0.0710 (10)
H9	0.3731	0.6660	0.3728	0.085*
C10	0.2308 (2)	0.5826 (8)	0.36834 (14)	0.0575 (8)
C11	0.1552 (2)	0.4251 (8)	0.32992 (14)	0.0533 (7)
C12	0.0631 (2)	0.4448 (10)	0.35059 (15)	0.0704 (10)
H12	0.0128	0.3420	0.3255	0.084*
C13	0.0467 (3)	0.6102 (10)	0.40623 (17)	0.0794 (11)
H13	−0.0145	0.6170	0.4198	0.095*
C14	0.1205 (3)	0.7717 (11)	0.44378 (16)	0.0804 (11)
H14	0.1083	0.8883	0.4817	0.097*
C15	0.2101 (3)	0.7583 (10)	0.42496 (17)	0.0722 (10)
H15	0.2589	0.8676	0.4501	0.087*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0693 (18)	0.071 (2)	0.0551 (13)	0.0114 (18)	0.0037 (13)	0.0008 (16)
O1	0.0745 (15)	0.0976 (19)	0.0678 (13)	0.0151 (17)	0.0001 (12)	−0.0131 (16)
O2	0.0503 (12)	0.0963 (19)	0.0721 (13)	−0.0068 (14)	0.0014 (10)	−0.0109 (14)
C1	0.090 (2)	0.067 (2)	0.0693 (19)	0.015 (3)	−0.0063 (19)	−0.006 (2)
C2	0.080 (2)	0.066 (2)	0.0609 (17)	0.006 (2)	−0.0040 (16)	−0.003 (2)
C3	0.081 (3)	0.061 (3)	0.057 (2)	0.000	0.012 (2)	0.000
C4	0.066 (2)	0.132 (4)	0.071 (2)	0.001 (3)	0.0156 (17)	−0.012 (3)
C5	0.0552 (19)	0.077 (2)	0.0519 (17)	0.010 (2)	−0.0001 (15)	0.0130 (19)
C6	0.0465 (17)	0.065 (2)	0.0489 (15)	0.0020 (19)	−0.0041 (13)	0.0072 (18)
C7	0.0489 (18)	0.062 (2)	0.0458 (15)	0.0028 (18)	−0.0001 (13)	0.0135 (17)
C8	0.0472 (18)	0.088 (3)	0.0649 (19)	−0.006 (2)	0.0019 (15)	0.007 (2)
C9	0.054 (2)	0.090 (3)	0.0660 (19)	−0.014 (2)	−0.0010 (16)	0.000 (2)
C10	0.0544 (18)	0.065 (2)	0.0518 (16)	0.0001 (19)	0.0018 (15)	0.0119 (19)
C11	0.0501 (17)	0.060 (2)	0.0490 (15)	0.0016 (17)	0.0035 (13)	0.0130 (18)
C12	0.055 (2)	0.095 (3)	0.0608 (18)	−0.001 (2)	0.0049 (15)	0.001 (2)
C13	0.067 (2)	0.100 (3)	0.073 (2)	0.008 (2)	0.0121 (19)	0.002 (2)
C14	0.089 (3)	0.090 (3)	0.0620 (19)	0.008 (3)	0.011 (2)	−0.003 (2)
C15	0.074 (2)	0.077 (3)	0.0620 (18)	−0.009 (2)	−0.0031 (17)	0.004 (2)

Geometric parameters (Å, º) top

N1—C5	1.278 (4)	C5—C7	1.465 (5)
N1—O1	1.417 (3)	C6—C7	1.380 (4)
O1—C1	1.422 (4)	C6—C11	1.424 (4)
O2—C6	1.360 (3)	C7—C8	1.428 (4)
O2—H2	0.8200	C8—C9	1.352 (4)
C1—C2	1.503 (4)	C8—H8	0.9300
C1—H1A	0.9700	C9—C10	1.402 (4)
C1—H1B	0.9700	C9—H9	0.9300
C2—C3	1.522 (5)	C10—C15	1.404 (5)
C2—H2A	0.9700	C10—C11	1.410 (4)
C2—H2B	0.9700	C11—C12	1.404 (4)
C3—C2ⁱ	1.522 (5)	C12—C13	1.345 (5)
C3—H3A	0.9700	C12—H12	0.9300
C3—H3B	0.9700	C13—C14	1.395 (5)
C4—C5	1.501 (4)	C13—H13	0.9300
C4—H4A	0.9600	C14—C15	1.355 (4)
C4—H4B	0.9600	C14—H14	0.9300
C4—H4C	0.9600	C15—H15	0.9300

C5—N1—O1	113.5 (3)	O2—C6—C7	122.6 (3)
N1—O1—C1	108.8 (2)	O2—C6—C11	115.3 (2)
C6—O2—H2	109.5	C7—C6—C11	122.2 (3)
O1—C1—C2	113.8 (3)	C6—C7—C8	116.8 (3)
O1—C1—H1A	108.8	C6—C7—C5	123.1 (3)
C2—C1—H1A	108.8	C8—C7—C5	120.1 (3)
O1—C1—H1B	108.8	C9—C8—C7	122.3 (3)
C2—C1—H1B	108.8	C9—C8—H8	118.9
H1A—C1—H1B	107.7	C7—C8—H8	118.9
C1—C2—C3	112.0 (3)	C8—C9—C10	121.0 (3)
C1—C2—H2A	109.2	C8—C9—H9	119.5
C3—C2—H2A	109.2	C10—C9—H9	119.5
C1—C2—H2B	109.2	C9—C10—C15	122.8 (3)
C3—C2—H2B	109.2	C9—C10—C11	119.0 (3)
H2A—C2—H2B	107.9	C15—C10—C11	118.2 (3)
C2—C3—C2ⁱ	112.9 (5)	C12—C11—C10	119.0 (3)
C2—C3—H3A	109.0	C12—C11—C6	122.3 (3)
C2ⁱ—C3—H3A	109.0	C10—C11—C6	118.8 (3)
C2—C3—H3B	109.0	C13—C12—C11	121.0 (3)
C2ⁱ—C3—H3B	109.0	C13—C12—H12	119.5
H3A—C3—H3B	107.8	C11—C12—H12	119.5
C5—C4—H4A	109.5	C12—C13—C14	120.6 (3)
C5—C4—H4B	109.5	C12—C13—H13	119.7
H4A—C4—H4B	109.5	C14—C13—H13	119.7
C5—C4—H4C	109.5	C15—C14—C13	119.8 (4)
H4A—C4—H4C	109.5	C15—C14—H14	120.1
H4B—C4—H4C	109.5	C13—C14—H14	120.1
N1—C5—C7	116.3 (3)	C14—C15—C10	121.4 (4)
N1—C5—C4	122.8 (3)	C14—C15—H15	119.3
C7—C5—C4	120.9 (3)	C10—C15—H15	119.3

C5—N1—O1—C1	178.9 (3)	C8—C9—C10—C15	−179.8 (4)
N1—O1—C1—C2	69.9 (4)	C8—C9—C10—C11	−0.7 (5)
O1—C1—C2—C3	177.5 (2)	C9—C10—C11—C12	179.5 (3)
C1—C2—C3—C2ⁱ	176.6 (3)	C15—C10—C11—C12	−1.4 (5)
O1—N1—C5—C7	178.7 (3)	C9—C10—C11—C6	0.4 (4)
O1—N1—C5—C4	0.9 (5)	C15—C10—C11—C6	179.5 (3)
O2—C6—C7—C8	−178.8 (3)	O2—C6—C11—C12	0.3 (5)
C11—C6—C7—C8	1.3 (5)	C7—C6—C11—C12	−179.8 (3)
O2—C6—C7—C5	0.9 (5)	O2—C6—C11—C10	179.4 (3)
C11—C6—C7—C5	−179.0 (3)	C7—C6—C11—C10	−0.7 (5)
N1—C5—C7—C6	−3.4 (5)	C10—C11—C12—C13	−0.2 (5)
C4—C5—C7—C6	174.5 (4)	C6—C11—C12—C13	178.9 (3)
N1—C5—C7—C8	176.3 (3)	C11—C12—C13—C14	1.5 (6)
C4—C5—C7—C8	−5.8 (5)	C12—C13—C14—C15	−1.2 (6)
C6—C7—C8—C9	−1.6 (5)	C13—C14—C15—C10	−0.4 (6)
C5—C7—C8—C9	178.6 (3)	C9—C10—C15—C14	−179.2 (4)
C7—C8—C9—C10	1.4 (5)	C11—C10—C15—C14	1.7 (6)

Symmetry code: (i) −x, y, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···N1	0.82	1.83	2.552 (3)	145

Experimental details

Crystal data
Chemical formula	C₂₉H₃₀N₂O₄
M_r	470.55
Crystal system, space group	Monoclinic, C2
Temperature (K)	298
a, b, c (Å)	14.0683 (12), 4.5659 (7), 19.048 (2)
β (°)	97.321 (1)
V (Å³)	1213.6 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.49 × 0.45 × 0.21

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.959, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	3170, 1218, 814
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.111, 1.02
No. of reflections	1218
No. of parameters	159
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.11, −0.13

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), 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
O2—H2···N1	0.82	1.83	2.552 (3)	145.00

Acknowledgements

The authors acknowledge finanical support from the `Jing Lan' Talent Engineering Fund of Lanzhou Jiaotong University.

References

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