2-(2,4,6-Trimethyl­phen­yl)-1,10-phenanthroline

Zhao, Y.; Zhang, Y.; Yang, P.; Wu, B.

doi:10.1107/S1600536809010800

organic compounds

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ISSN: 2056-9890

Volume 65| Part 4| April 2009| Page o932

doi:10.1107/S1600536809010800

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2-(2,4,6-Trimethylphenyl)-1,10-phenanthroline

Yuxin Zhao,^a Yongping Zhang,^a ^* Peiju Yang ^b and Biao Wu ^b

^aState Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China, and ^bState Key Laboratory for Oxo Synthesis & Selective Oxidation, Lanzhou Institute of Chemical Physics, CAS, Lanzhou 730000, People's Republic of China
^*Correspondence e-mail: zhangyongp@lzu.edu.cn

(Received 13 March 2009; accepted 24 March 2009; online 1 April 2009)

In the title molecule, C₂₁H₁₈N₂, the mean plane of the benzene ring of the mesityl group forms a dihedral angle of 82.69 (4)° with that of the phenanthroline ring system. The crystal structure is stabilized by π–π stacking interactions between the phenanthroline system and the benzene ring of the mesityl group of a symmetry-related molecule, with centroid–centroid distances of 3.7776 (14) and 3.7155 (13) Å.

Related literature

For background information on phenanthroline derivatives, see: Schmittel et al. (2001 ); Garas & Vagg (2000 ). For information on phenanthroline ligands as used in coordination chemistry, see: Sauvage (1990 ). For the synthetic procedure, see: Schmittel & Ganz (1997 ).

Experimental

Crystal data

C₂₁H₁₈N₂
M_r = 298.37
Monoclinic, P 2₁ /c
a = 14.5778 (19) Å
b = 8.9877 (11) Å
c = 13.5790 (11) Å
β = 112.166 (4)°
V = 1647.6 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 293 K
0.35 × 0.23 × 0.19 mm

Data collection

Bruker SMART area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.976, T_max = 0.987
9474 measured reflections
3511 independent reflections
2150 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.057
wR(F²) = 0.181
S = 1.06
3511 reflections
208 parameters
H-atom parameters constrained
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Data collection: SMART (Bruker, 1998 ); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1999 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809010800/lh2789sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809010800/lh2789Isup2.hkl

checkCIF report

Comment top

Phenanthroline derivatives are well known nitrogen-containing heterocyclic compounds, and their syntheses have been extensively studied (Garas & Vagg 2000, Schmittel et al., 2001). 1,10-Phenanthroline ligands have been widely used in transition metal coordination chemistry because their steric and electronic environment can be conveniently tailored by varying the substituents (Sauvage, 1990). We have therefore synthesized a series of 2-substituted-1,10-phenanthrolines including the title compound to study their applications in metal coordination chemistry.

The molecular structure of the title compound is shown in Fig. 1. The benzene ring of the mesityl group forms a dihedral angle of 82.69 (4)° with the mean-plane of phenanthroline ring system. The crystal structure is stabilized by intermolecular π-π stacking interactions between the phenanthroline moiety and the benzene ring of a symmetry related molecule (Fig. 2) where Cg1···Cg2 and Cg2···Cg3 are 3.7776 (14)Å and 3.7155 (13)Å, respectively (with the perpendicaular distances for each being ca. 3.5Å). Cg1, Cg2 and Cg3 are the centroids defined by ring atoms N1/C1-C4/C12, C13-C18 and C4-C12, respectively.

Related literature top

For background information on phenanthroline derivatives, see: Schmittel et al. (2001); Garas & Vagg (2000). For information on phenanthroline ligands as used in coordination chemistry, see: Sauvage (1990). For the synthetic procedure, see: Schmittel & Ganz (1997).

Experimental top

The title compound was synthesized according to a reported literature procedures (Schmittel & Ganz 1997). Crystals suitable for X-ray diffraction were obtained evaporation of a solution of the title compound in ethyl acetate.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. Part of the crystal structure showing the /p-/p stacking interactions (dashed lines) between the phenanthroline ring system and symmetry related benzene rings. H atoms have been omitted for clarity.

2-(2,4,6-Trimethylphenyl)-1,10-phenanthroline top

Crystal data top

C₂₁H₁₈N₂	F(000) = 632
M_r = 298.37	D_x = 1.203 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2140 reflections
a = 14.5778 (19) Å	θ = 2.7–25.4°
b = 8.9877 (11) Å	µ = 0.07 mm⁻¹
c = 13.5790 (11) Å	T = 293 K
β = 112.166 (4)°	Block, colourless
V = 1647.6 (3) Å³	0.35 × 0.23 × 0.19 mm
Z = 4

Data collection top

Bruker APEXII area-detector diffractometer	3511 independent reflections
Radiation source: fine-focus sealed tube	2150 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
ω scans	θ_max = 26.9°, θ_min = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −18→17
T_min = 0.976, T_max = 0.987	k = −11→10
9474 measured reflections	l = −17→15

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)] = 0.057	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.181	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.084P)² + 0.1669P] where P = (F_o² + 2F_c²)/3
3511 reflections	(Δ/σ)_max < 0.001
208 parameters	Δρ_max = 0.24 e Å⁻³
0 restraints	Δρ_min = −0.19 e Å⁻³

Crystal data top

C₂₁H₁₈N₂	V = 1647.6 (3) Å³
M_r = 298.37	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.5778 (19) Å	µ = 0.07 mm⁻¹
b = 8.9877 (11) Å	T = 293 K
c = 13.5790 (11) Å	0.35 × 0.23 × 0.19 mm
β = 112.166 (4)°

Data collection top

Bruker APEXII area-detector diffractometer	3511 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2150 reflections with I > 2σ(I)
T_min = 0.976, T_max = 0.987	R_int = 0.031
9474 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.057	0 restraints
wR(F²) = 0.181	H-atom parameters constrained
S = 1.06	Δρ_max = 0.24 e Å⁻³
3511 reflections	Δρ_min = −0.19 e Å⁻³
208 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
N1	0.09525 (12)	0.20234 (19)	0.35983 (13)	0.0639 (5)
N2	0.23560 (10)	0.39234 (16)	0.49200 (11)	0.0503 (4)
C1	0.02762 (16)	0.1138 (3)	0.29282 (19)	0.0802 (7)
H1A	−0.0102	0.0559	0.3200	0.096*
C2	0.00892 (17)	0.1011 (3)	0.18436 (19)	0.0830 (7)
H2A	−0.0401	0.0373	0.1414	0.100*
C3	0.06359 (15)	0.1835 (3)	0.14320 (17)	0.0709 (6)
H3A	0.0527	0.1771	0.0713	0.085*
C4	0.13668 (13)	0.2784 (2)	0.21015 (14)	0.0527 (5)
C5	0.19644 (15)	0.3666 (2)	0.17047 (15)	0.0605 (5)
H5A	0.1874	0.3607	0.0990	0.073*
C6	0.26533 (15)	0.4579 (2)	0.23519 (16)	0.0617 (5)
H6A	0.3030	0.5157	0.2077	0.074*
C7	0.28227 (13)	0.4683 (2)	0.34577 (14)	0.0513 (5)
C8	0.35443 (15)	0.5618 (2)	0.41600 (16)	0.0668 (6)
H8A	0.3941	0.6200	0.3915	0.080*
C9	0.36619 (15)	0.5671 (2)	0.52044 (16)	0.0672 (6)
H9A	0.4153	0.6266	0.5679	0.081*
C10	0.30418 (13)	0.4828 (2)	0.55576 (14)	0.0518 (5)
C11	0.22481 (12)	0.38370 (19)	0.38836 (13)	0.0449 (4)
C12	0.14971 (12)	0.2850 (2)	0.31808 (14)	0.0486 (5)
C13	0.31208 (14)	0.4929 (2)	0.66863 (14)	0.0544 (5)
C14	0.38347 (14)	0.4096 (2)	0.74841 (16)	0.0627 (6)
C15	0.38632 (16)	0.4189 (3)	0.85174 (16)	0.0690 (6)
H15A	0.4337	0.3638	0.9048	0.083*
C16	0.32177 (18)	0.5063 (3)	0.87862 (16)	0.0703 (6)
C17	0.25303 (17)	0.5879 (2)	0.79860 (17)	0.0704 (6)
H17A	0.2094	0.6485	0.8156	0.085*
C18	0.24611 (15)	0.5836 (2)	0.69393 (16)	0.0622 (5)
C19	0.45479 (16)	0.3098 (3)	0.72337 (19)	0.0877 (8)
H19B	0.4980	0.2623	0.7874	0.132*
H19C	0.4933	0.3679	0.6937	0.132*
H19D	0.4185	0.2354	0.6730	0.132*
C20	0.16739 (18)	0.6713 (3)	0.6093 (2)	0.0847 (7)
H20B	0.1293	0.7268	0.6409	0.127*
H20C	0.1246	0.6045	0.5568	0.127*
H20D	0.1980	0.7387	0.5761	0.127*
C21	0.3232 (2)	0.5084 (3)	0.99054 (18)	0.0934 (8)
H21B	0.3756	0.4453	1.0352	0.140*
H21C	0.2609	0.4729	0.9900	0.140*
H21D	0.3341	0.6083	1.0175	0.140*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0589 (9)	0.0730 (11)	0.0617 (10)	−0.0201 (8)	0.0249 (9)	−0.0090 (9)
N2	0.0487 (8)	0.0586 (9)	0.0419 (8)	−0.0056 (7)	0.0153 (7)	−0.0014 (7)
C1	0.0678 (13)	0.0949 (17)	0.0796 (16)	−0.0298 (13)	0.0299 (13)	−0.0175 (14)
C2	0.0660 (14)	0.1019 (19)	0.0699 (15)	−0.0276 (13)	0.0131 (12)	−0.0222 (14)
C3	0.0640 (13)	0.0850 (15)	0.0522 (12)	−0.0036 (12)	0.0088 (11)	−0.0116 (11)
C4	0.0469 (10)	0.0614 (11)	0.0446 (10)	0.0044 (8)	0.0112 (8)	−0.0032 (9)
C5	0.0663 (12)	0.0735 (13)	0.0413 (10)	0.0042 (10)	0.0197 (10)	0.0016 (10)
C6	0.0669 (12)	0.0732 (13)	0.0515 (12)	−0.0060 (11)	0.0299 (10)	0.0040 (10)
C7	0.0512 (10)	0.0565 (11)	0.0459 (10)	−0.0018 (8)	0.0181 (9)	0.0017 (9)
C8	0.0672 (13)	0.0771 (14)	0.0613 (13)	−0.0227 (11)	0.0303 (11)	−0.0009 (11)
C9	0.0650 (12)	0.0785 (14)	0.0557 (12)	−0.0278 (11)	0.0201 (10)	−0.0117 (11)
C10	0.0498 (10)	0.0587 (11)	0.0440 (10)	−0.0050 (9)	0.0146 (9)	−0.0012 (9)
C11	0.0427 (9)	0.0509 (10)	0.0409 (10)	0.0023 (7)	0.0156 (8)	0.0014 (8)
C12	0.0421 (9)	0.0537 (10)	0.0478 (11)	0.0038 (8)	0.0145 (8)	−0.0013 (8)
C13	0.0530 (10)	0.0630 (12)	0.0425 (10)	−0.0142 (9)	0.0127 (9)	−0.0060 (9)
C14	0.0535 (11)	0.0804 (14)	0.0493 (12)	−0.0108 (10)	0.0138 (10)	−0.0015 (10)
C15	0.0664 (13)	0.0866 (15)	0.0448 (12)	−0.0146 (11)	0.0105 (10)	0.0030 (11)
C16	0.0823 (15)	0.0817 (15)	0.0463 (12)	−0.0292 (13)	0.0234 (12)	−0.0135 (11)
C17	0.0813 (15)	0.0749 (14)	0.0602 (13)	−0.0117 (12)	0.0325 (12)	−0.0173 (11)
C18	0.0672 (13)	0.0644 (12)	0.0523 (12)	−0.0087 (10)	0.0194 (10)	−0.0075 (10)
C19	0.0653 (14)	0.128 (2)	0.0650 (15)	0.0148 (14)	0.0187 (12)	0.0125 (14)
C20	0.0911 (16)	0.0851 (16)	0.0751 (16)	0.0156 (14)	0.0281 (14)	−0.0010 (13)
C21	0.124 (2)	0.1078 (19)	0.0529 (13)	−0.0323 (17)	0.0386 (14)	−0.0142 (13)

Geometric parameters (Å, º) top

N1—C1	1.325 (3)	C10—C13	1.496 (3)
N1—C12	1.357 (2)	C11—C12	1.452 (2)
N2—C10	1.325 (2)	C13—C18	1.399 (3)
N2—C11	1.358 (2)	C13—C14	1.402 (3)
C1—C2	1.398 (3)	C14—C15	1.391 (3)
C1—H1A	0.9300	C14—C19	1.506 (3)
C2—C3	1.353 (3)	C15—C16	1.377 (3)
C2—H2A	0.9300	C15—H15A	0.9300
C3—C4	1.400 (3)	C16—C17	1.379 (3)
C3—H3A	0.9300	C16—C21	1.512 (3)
C4—C12	1.406 (2)	C17—C18	1.387 (3)
C4—C5	1.426 (3)	C17—H17A	0.9300
C5—C6	1.337 (3)	C18—C20	1.505 (3)
C5—H5A	0.9300	C19—H19B	0.9600
C6—C7	1.430 (3)	C19—H19C	0.9600
C6—H6A	0.9300	C19—H19D	0.9600
C7—C8	1.402 (3)	C20—H20B	0.9600
C7—C11	1.407 (2)	C20—H20C	0.9600
C8—C9	1.364 (3)	C20—H20D	0.9600
C8—H8A	0.9300	C21—H21B	0.9600
C9—C10	1.396 (3)	C21—H21C	0.9600
C9—H9A	0.9300	C21—H21D	0.9600

C1—N1—C12	116.26 (18)	C4—C12—C11	118.84 (16)
C10—N2—C11	118.42 (15)	C18—C13—C14	120.00 (18)
N1—C1—C2	124.9 (2)	C18—C13—C10	119.51 (17)
N1—C1—H1A	117.6	C14—C13—C10	120.47 (18)
C2—C1—H1A	117.6	C15—C14—C13	118.6 (2)
C3—C2—C1	118.6 (2)	C15—C14—C19	120.2 (2)
C3—C2—H2A	120.7	C13—C14—C19	121.19 (18)
C1—C2—H2A	120.7	C16—C15—C14	122.6 (2)
C2—C3—C4	119.2 (2)	C16—C15—H15A	118.7
C2—C3—H3A	120.4	C14—C15—H15A	118.7
C4—C3—H3A	120.4	C15—C16—C17	117.45 (19)
C3—C4—C12	118.22 (18)	C15—C16—C21	121.5 (2)
C3—C4—C5	121.17 (18)	C17—C16—C21	121.0 (2)
C12—C4—C5	120.61 (16)	C16—C17—C18	122.9 (2)
C6—C5—C4	120.49 (17)	C16—C17—H17A	118.6
C6—C5—H5A	119.8	C18—C17—H17A	118.6
C4—C5—H5A	119.8	C17—C18—C13	118.5 (2)
C5—C6—C7	121.31 (18)	C17—C18—C20	120.5 (2)
C5—C6—H6A	119.3	C13—C18—C20	120.96 (18)
C7—C6—H6A	119.3	C14—C19—H19B	109.5
C8—C7—C11	117.04 (17)	C14—C19—H19C	109.5
C8—C7—C6	122.79 (17)	H19B—C19—H19C	109.5
C11—C7—C6	120.17 (16)	C14—C19—H19D	109.5
C9—C8—C7	119.75 (18)	H19B—C19—H19D	109.5
C9—C8—H8A	120.1	H19C—C19—H19D	109.5
C7—C8—H8A	120.1	C18—C20—H20B	109.5
C8—C9—C10	119.64 (18)	C18—C20—H20C	109.5
C8—C9—H9A	120.2	H20B—C20—H20C	109.5
C10—C9—H9A	120.2	C18—C20—H20D	109.5
N2—C10—C9	122.36 (17)	H20B—C20—H20D	109.5
N2—C10—C13	117.01 (16)	H20C—C20—H20D	109.5
C9—C10—C13	120.63 (16)	C16—C21—H21B	109.5
N2—C11—C7	122.74 (16)	C16—C21—H21C	109.5
N2—C11—C12	118.68 (15)	H21B—C21—H21C	109.5
C7—C11—C12	118.57 (15)	C16—C21—H21D	109.5
N1—C12—C4	122.83 (16)	H21B—C21—H21D	109.5
N1—C12—C11	118.33 (16)	H21C—C21—H21D	109.5

C12—N1—C1—C2	−0.3 (3)	C3—C4—C12—C11	−179.59 (16)
N1—C1—C2—C3	0.5 (4)	C5—C4—C12—C11	0.3 (3)
C1—C2—C3—C4	0.0 (3)	N2—C11—C12—N1	−1.8 (2)
C2—C3—C4—C12	−0.5 (3)	C7—C11—C12—N1	179.26 (15)
C2—C3—C4—C5	179.6 (2)	N2—C11—C12—C4	178.47 (15)
C3—C4—C5—C6	179.35 (18)	C7—C11—C12—C4	−0.5 (2)
C12—C4—C5—C6	−0.5 (3)	N2—C10—C13—C18	−80.7 (2)
C4—C5—C6—C7	1.0 (3)	C9—C10—C13—C18	98.5 (2)
C5—C6—C7—C8	179.43 (19)	N2—C10—C13—C14	97.8 (2)
C5—C6—C7—C11	−1.2 (3)	C9—C10—C13—C14	−82.9 (2)
C11—C7—C8—C9	0.1 (3)	C18—C13—C14—C15	0.5 (3)
C6—C7—C8—C9	179.5 (2)	C10—C13—C14—C15	−178.08 (17)
C7—C8—C9—C10	−1.9 (3)	C18—C13—C14—C19	179.37 (18)
C11—N2—C10—C9	−1.0 (3)	C10—C13—C14—C19	0.8 (3)
C11—N2—C10—C13	178.28 (15)	C13—C14—C15—C16	0.1 (3)
C8—C9—C10—N2	2.5 (3)	C19—C14—C15—C16	−178.8 (2)
C8—C9—C10—C13	−176.75 (19)	C14—C15—C16—C17	−0.7 (3)
C10—N2—C11—C7	−1.0 (3)	C14—C15—C16—C21	176.9 (2)
C10—N2—C11—C12	−179.93 (15)	C15—C16—C17—C18	0.8 (3)
C8—C7—C11—N2	1.4 (3)	C21—C16—C17—C18	−176.9 (2)
C6—C7—C11—N2	−178.00 (16)	C16—C17—C18—C13	−0.2 (3)
C8—C7—C11—C12	−179.66 (16)	C16—C17—C18—C20	177.98 (19)
C6—C7—C11—C12	0.9 (3)	C14—C13—C18—C17	−0.4 (3)
C1—N1—C12—C4	−0.3 (3)	C10—C13—C18—C17	178.17 (17)
C1—N1—C12—C11	180.00 (17)	C14—C13—C18—C20	−178.62 (18)
C3—C4—C12—N1	0.7 (3)	C10—C13—C18—C20	0.0 (3)
C5—C4—C12—N1	−179.46 (16)

Experimental details

Crystal data
Chemical formula	C₂₁H₁₈N₂
M_r	298.37
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	14.5778 (19), 8.9877 (11), 13.5790 (11)
β (°)	112.166 (4)
V (Å³)	1647.6 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.35 × 0.23 × 0.19

Data collection
Diffractometer	Bruker APEXII area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.976, 0.987
No. of measured, independent and observed [I > 2σ(I)] reflections	9474, 3511, 2150
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.637

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.181, 1.06
No. of reflections	3511
No. of parameters	208
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.19

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1999).

References

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Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
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Schmittel, M., Michel, C., Liu, S.-X., Schildbach, D. & Fenske, D. (2001). Eur. J. Inorg. Chem. pp. 1155–1166. CrossRef 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