1-(4-Chloro­phen­yl)-3-phenyl-1H-pyrazol-5(4H)-one

Ding, Y.-J.; Zhao, C.-X.

doi:10.1107/S1600536809055263

organic compounds

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ISSN: 2056-9890

Volume 66| Part 3| March 2010| Page o709

doi:10.1107/S1600536809055263

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1-(4-Chlorophenyl)-3-phenyl-1H-pyrazol-5(4H)-one

Yong-Jie Ding ^a and Chun-Xiang Zhao ^b ^*

^aDepartment of Chemistry, East China Normal University, Shanghai 200062, People's Republic of China, and ^bDepartment of Chemistry, Zhoukou Normal University, Zhoukou 466001, People's Republic of China
^*Correspondence e-mail: chunxiangzhao@163.com

(Received 9 December 2009; accepted 23 December 2009; online 27 February 2010)

In the crystal of the title compound, C₁₅H₁₁ClN₂O, the molecules are linked by C—H⋯O and weak C—H⋯π interactions. The chlorophenyl and phenyl rings are twisted with respect to the central pyrazolone ring, making dihedral angles of 18.23 (8) and 8.35 (8)°, respectively. The N—N and C=O bond lengths are comparable to those reported for pyrazolone compounds.

Related literature

For the properties and applications of pyrazolones and their derivatives, see: Bao et al. (2006 ); Bose et al. (2005 ); Ito et al. (2001 ); Li et al. (2000 ); Shi, et al. (2005 ); Whitaker (1995 ). For the synthesis, see: Jensen (1959 ). For related structures, see: Bovio et al. (1974 ); Dardonville et al. (1998 ); Ferretti et al. (1985 ); Holzer et al. (1999 ).

Experimental

Crystal data

C₁₅H₁₁ClN₂O
M_r = 270.71
Monoclinic, P 2₁ /c
a = 11.2593 (4) Å
b = 12.1848 (4) Å
c = 9.5498 (3) Å
β = 103.053 (1)°
V = 1276.31 (7) Å³
Z = 4
Mo Kα radiation
μ = 0.29 mm⁻¹
T = 296 K
0.32 × 0.28 × 0.15 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
17039 measured reflections
3172 independent reflections
2578 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.111
S = 1.04
3172 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C10–C15 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8B⋯O1ⁱ	0.97	2.40	3.3115 (19)	156
C8—H8A⋯Cg1ⁱⁱ	0.97	2.76	3.5026 (17)	134
Symmetry codes: (i) $[x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (ii) -x+2, -y+1, -z+2.

Table 2
Comparison of C=O and N—N bond lengths (Å) between the title compound and reported pyrazolone compounds.

Compound	C=O	N—N
C₁₃H₁₄N₂O₂^a	1.313 (2)	1.395 (2)
C₁₉H₁₆N₂O₂^a	1.261 (2)	1.404 (2)
C₁₅H₁₂N₂O₂S^a	1.246 (2)	1.373 (2)
C₂₂H₁₅ClN₂O^c	1.228 (2)	1.405 (2)
C₁₆H₁₁N₃O^c	1.252 (3)	1.412 (4)
C₁₆H₁₀ClN₃O^c	1.250 (5)	1.420 (5)
C₁₀H₈N₄O₅^d	1.207 (3)	1.412 (2)
C₁₅H₁₁ClN₂O^e	1.213 (2)	1.404 (2)
Notes: (a) Holzer et al. (1999); (b) Bovio et al. (1974); (c) Ferretti et al. (1985); (d) Dardonville et al. (1998); (e) this work.

Data collection: APEX2 (Bruker, 2005 ); cell refinement: SAINT (Bruker, 2005); 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: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809055263/dn2522sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809055263/dn2522Isup2.hkl

checkCIF report

Comment top

Pyrazolones and their derivatives constitute a group of organic compounds that have been extensively studied due to their diverse properties and applications. For example, many more applications have been devised for this group of molecules in the pharmaceutical field. Moreover, they have been applied to the solvent extraction of metal ions (Bose et al., 2005), for analytical purposes (Ito et al., 2001), in the preparation of azo colorants (Whitaker, 1995), as ligands in complexes with catalytic activity (Bao et al., 2006) and in the synthesis of rare earth metal complexes with interesting photophysical properties (Shi et al., 2005). Also, it is important in understanding the behaviour of these compounds with respect to the mechanisms of pharmacological activities (Li et al., 2000). In order to expand this field, the novel title compound (I) has been synthesized, and its crystal structure is reported herein for the first time.

The asymmetric unit of the title compound is built up from a central pyrazolone ring substituted in 1,3 by a 4-chlorophenyl and a phenyl rings (Fig. 1). The chlorophenyl and phenyl rings are slightly twisted with respect to the central pyrazolone ring making dihedral angles of 18.23 (8)° and 8.35 (8)° respectively, thus indicating a high degree of conjugation and electron delocalization.The N(1)–N(2) and C(7)=O(1) distances are comparable, within experimental errors, with related pyrazolones reported in the literature (Table 2).

The cohesion of the crystal is assured by weak C-H···O and C-H···π interactions (Table 1).

Related literature top

For the properties and applications of pyrazolones and their derivatives, see: Bao et al. (2006); Bose et al. (2005); Ito et al. (2001); Li et al. (2000); Shi, et al. (2005); Whitaker (1995). For the synthesis, see: Jensen (1959).For related structures, see: Bovio et al. (1974); Dardonville et al. (1998); Ferretti et al. (1985); Holzer et al. (1999).

Experimental top

All reagents were obtained from commercial sources and used without further purification. 1-(4-chlorophenyl)-3-phenyl-1H-pyrazol-5(4H)-one was synthesized according to the method proposed by Jensen (1959). (yield 84.5%; m.p. 435–436 K). Analysis required for C₁₅H₁₁ClN₂O: C 66.55%, H 4.10%, N10.35%; found: C 66.51, H 4.08, N 10.41%. Block-like golden single crystals of CPP were grown from ethanol by slow evaporation over a period of several weeks.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I) (thermal ellipsoids are shown at 30% probability levels).

1-(4-Chlorophenyl)-3-phenyl-1H-pyrazol-5(4H)-one top

Crystal data top

C₁₅H₁₁ClN₂O	F(000) = 560.0
M_r = 270.71	D_x = 1.409 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 8730 reflections
a = 11.2593 (4) Å	θ = 2.5–28.4°
b = 12.1848 (4) Å	µ = 0.29 mm⁻¹
c = 9.5498 (3) Å	T = 296 K
β = 103.053 (1)°	Block, yellow
V = 1276.31 (7) Å³	0.32 × 0.28 × 0.15 mm
Z = 4

Data collection top

Bruker SMART CCD area-detector diffractometer	2578 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.021
Graphite monochromator	θ_max = 28.4°, θ_min = 1.9°
ϕ and ω scans	h = −14→15
17039 measured reflections	k = −15→16
3172 independent reflections	l = −12→11

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.111	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0526P)² + 0.3591P] where P = (F_o² + 2F_c²)/3
3172 reflections	(Δ/σ)_max < 0.001
172 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₁₅H₁₁ClN₂O	V = 1276.31 (7) Å³
M_r = 270.71	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 11.2593 (4) Å	µ = 0.29 mm⁻¹
b = 12.1848 (4) Å	T = 296 K
c = 9.5498 (3) Å	0.32 × 0.28 × 0.15 mm
β = 103.053 (1)°

Data collection top

Bruker SMART CCD area-detector diffractometer	2578 reflections with I > 2σ(I)
17039 measured reflections	R_int = 0.021
3172 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.111	H-atom parameters constrained
S = 1.04	Δρ_max = 0.23 e Å⁻³
3172 reflections	Δρ_min = −0.20 e Å⁻³
172 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
Cl1	0.49588 (4)	0.36865 (4)	0.10838 (4)	0.06295 (16)
N2	0.73364 (11)	0.53865 (9)	0.68321 (12)	0.0405 (3)
N1	0.75985 (10)	0.46368 (9)	0.79773 (12)	0.0396 (3)
C7	0.76387 (14)	0.64516 (11)	0.72628 (15)	0.0442 (3)
C8	0.82119 (14)	0.63688 (11)	0.88421 (15)	0.0434 (3)
H8A	0.9060	0.6593	0.9047	0.052*
H8B	0.7777	0.6811	0.9407	0.052*
C1	0.67906 (12)	0.49854 (11)	0.54432 (14)	0.0380 (3)
C4	0.56921 (13)	0.41944 (13)	0.27598 (14)	0.0445 (3)
O1	0.74620 (13)	0.72658 (9)	0.65145 (12)	0.0620 (3)
C5	0.56870 (15)	0.35700 (12)	0.39612 (16)	0.0491 (3)
H5	0.5317	0.2883	0.3866	0.059*
C10	0.85009 (12)	0.46390 (11)	1.05204 (14)	0.0392 (3)
C9	0.80911 (12)	0.51759 (11)	0.91237 (14)	0.0375 (3)
C3	0.62544 (16)	0.51956 (13)	0.28785 (16)	0.0538 (4)
H3	0.6260	0.5607	0.2060	0.065*
C15	0.82395 (14)	0.35388 (12)	1.07152 (17)	0.0476 (3)
H15	0.7787	0.3135	0.9952	0.057*
C6	0.62340 (13)	0.39676 (12)	0.53086 (15)	0.0448 (3)
H6	0.6228	0.3551	0.6123	0.054*
C11	0.91727 (14)	0.52294 (13)	1.16804 (15)	0.0481 (3)
H11	0.9340	0.5967	1.1569	0.058*
C13	0.93286 (17)	0.36390 (16)	1.31805 (18)	0.0617 (4)
H13	0.9606	0.3304	1.4069	0.074*
C2	0.68150 (16)	0.55939 (13)	0.42195 (16)	0.0531 (4)
H2	0.7209	0.6270	0.4303	0.064*
C12	0.95927 (16)	0.47258 (15)	1.29984 (16)	0.0582 (4)
H12	1.0054	0.5122	1.3763	0.070*
C14	0.86514 (16)	0.30462 (15)	1.20418 (18)	0.0594 (4)
H14	0.8472	0.2313	1.2168	0.071*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0769 (3)	0.0676 (3)	0.0378 (2)	0.0076 (2)	−0.00071 (18)	−0.01026 (16)
N2	0.0514 (6)	0.0331 (5)	0.0348 (5)	−0.0008 (5)	0.0052 (5)	0.0022 (4)
N1	0.0474 (6)	0.0345 (6)	0.0352 (5)	−0.0001 (5)	0.0058 (5)	0.0031 (4)
C7	0.0551 (8)	0.0358 (7)	0.0416 (7)	−0.0025 (6)	0.0108 (6)	−0.0011 (5)
C8	0.0559 (8)	0.0347 (7)	0.0392 (7)	−0.0025 (6)	0.0101 (6)	−0.0032 (5)
C1	0.0415 (7)	0.0371 (7)	0.0347 (6)	0.0030 (5)	0.0071 (5)	−0.0001 (5)
C4	0.0479 (7)	0.0494 (8)	0.0342 (6)	0.0093 (6)	0.0053 (5)	−0.0045 (6)
O1	0.0983 (9)	0.0359 (5)	0.0487 (6)	−0.0051 (5)	0.0098 (6)	0.0068 (5)
C5	0.0574 (9)	0.0413 (7)	0.0435 (7)	−0.0040 (6)	0.0007 (6)	−0.0003 (6)
C10	0.0409 (7)	0.0420 (7)	0.0354 (6)	0.0008 (5)	0.0100 (5)	0.0003 (5)
C9	0.0408 (6)	0.0354 (6)	0.0369 (6)	−0.0001 (5)	0.0099 (5)	−0.0018 (5)
C3	0.0736 (10)	0.0533 (9)	0.0353 (7)	−0.0010 (7)	0.0141 (7)	0.0050 (6)
C15	0.0506 (8)	0.0447 (8)	0.0452 (7)	−0.0065 (6)	0.0059 (6)	0.0028 (6)
C6	0.0535 (8)	0.0408 (7)	0.0370 (7)	−0.0022 (6)	0.0035 (6)	0.0048 (5)
C11	0.0593 (9)	0.0468 (8)	0.0380 (7)	−0.0041 (6)	0.0106 (6)	−0.0038 (6)
C13	0.0682 (10)	0.0733 (12)	0.0418 (8)	0.0019 (8)	0.0088 (7)	0.0161 (7)
C2	0.0733 (10)	0.0446 (8)	0.0422 (7)	−0.0109 (7)	0.0144 (7)	0.0013 (6)
C12	0.0662 (10)	0.0706 (11)	0.0355 (7)	−0.0048 (8)	0.0067 (7)	−0.0033 (7)
C14	0.0665 (10)	0.0543 (9)	0.0559 (9)	−0.0069 (8)	0.0106 (8)	0.0155 (7)

Geometric parameters (Å, º) top

Cl1—C4	1.7406 (14)	C10—C11	1.3923 (19)
N2—C7	1.3806 (17)	C10—C15	1.394 (2)
N2—N1	1.4042 (15)	C10—C9	1.4635 (18)
N2—C1	1.4169 (16)	C3—C2	1.382 (2)
N1—C9	1.2897 (17)	C3—H3	0.9300
C7—O1	1.2126 (17)	C15—C14	1.384 (2)
C7—C8	1.504 (2)	C15—H15	0.9300
C8—C9	1.4900 (18)	C6—H6	0.9300
C8—H8A	0.9700	C11—C12	1.384 (2)
C8—H8B	0.9700	C11—H11	0.9300
C1—C6	1.3824 (19)	C13—C12	1.377 (3)
C1—C2	1.3894 (19)	C13—C14	1.382 (3)
C4—C3	1.367 (2)	C13—H13	0.9300
C4—C5	1.378 (2)	C2—H2	0.9300
C5—C6	1.383 (2)	C12—H12	0.9300
C5—H5	0.9300	C14—H14	0.9300

C7—N2—N1	112.65 (11)	N1—C9—C8	112.52 (11)
C7—N2—C1	128.96 (11)	C10—C9—C8	125.29 (12)
N1—N2—C1	118.37 (10)	C4—C3—C2	119.75 (14)
C9—N1—N2	107.72 (11)	C4—C3—H3	120.1
O1—C7—N2	126.65 (14)	C2—C3—H3	120.1
O1—C7—C8	128.47 (13)	C14—C15—C10	120.14 (15)
N2—C7—C8	104.88 (11)	C14—C15—H15	119.9
C9—C8—C7	102.15 (11)	C10—C15—H15	119.9
C9—C8—H8A	111.3	C1—C6—C5	119.88 (13)
C7—C8—H8A	111.3	C1—C6—H6	120.1
C9—C8—H8B	111.3	C5—C6—H6	120.1
C7—C8—H8B	111.3	C12—C11—C10	120.47 (15)
H8A—C8—H8B	109.2	C12—C11—H11	119.8
C6—C1—C2	119.68 (13)	C10—C11—H11	119.8
C6—C1—N2	119.22 (12)	C12—C13—C14	119.98 (15)
C2—C1—N2	121.10 (12)	C12—C13—H13	120.0
C3—C4—C5	120.84 (13)	C14—C13—H13	120.0
C3—C4—Cl1	120.53 (11)	C3—C2—C1	120.03 (14)
C5—C4—Cl1	118.63 (12)	C3—C2—H2	120.0
C4—C5—C6	119.79 (14)	C1—C2—H2	120.0
C4—C5—H5	120.1	C13—C12—C11	120.14 (16)
C6—C5—H5	120.1	C13—C12—H12	119.9
C11—C10—C15	118.94 (13)	C11—C12—H12	119.9
C11—C10—C9	119.80 (13)	C13—C14—C15	120.32 (16)
C15—C10—C9	121.26 (13)	C13—C14—H14	119.8
N1—C9—C10	122.18 (12)	C15—C14—H14	119.8

C7—N2—N1—C9	−1.81 (16)	C15—C10—C9—C8	173.39 (14)
C1—N2—N1—C9	179.69 (11)	C7—C8—C9—N1	1.93 (16)
N1—N2—C7—O1	−176.48 (15)	C7—C8—C9—C10	−179.50 (13)
C1—N2—C7—O1	1.8 (3)	C5—C4—C3—C2	−0.7 (2)
N1—N2—C7—C8	2.95 (16)	Cl1—C4—C3—C2	178.94 (13)
C1—N2—C7—C8	−178.75 (13)	C11—C10—C15—C14	−0.4 (2)
O1—C7—C8—C9	176.62 (16)	C9—C10—C15—C14	179.13 (14)
N2—C7—C8—C9	−2.79 (15)	C2—C1—C6—C5	−1.1 (2)
C7—N2—C1—C6	−160.62 (14)	N2—C1—C6—C5	179.36 (13)
N1—N2—C1—C6	17.60 (18)	C4—C5—C6—C1	−0.5 (2)
C7—N2—C1—C2	19.9 (2)	C15—C10—C11—C12	1.2 (2)
N1—N2—C1—C2	−161.90 (13)	C9—C10—C11—C12	−178.37 (13)
C3—C4—C5—C6	1.4 (2)	C4—C3—C2—C1	−1.0 (3)
Cl1—C4—C5—C6	−178.24 (12)	C6—C1—C2—C3	1.9 (2)
N2—N1—C9—C10	−178.86 (11)	N2—C1—C2—C3	−178.65 (14)
N2—N1—C9—C8	−0.24 (15)	C14—C13—C12—C11	0.6 (3)
C11—C10—C9—N1	171.35 (13)	C10—C11—C12—C13	−1.3 (3)
C15—C10—C9—N1	−8.2 (2)	C12—C13—C14—C15	0.2 (3)
C11—C10—C9—C8	−7.1 (2)	C10—C15—C14—C13	−0.3 (3)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C10–C15 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8B···O1ⁱ	0.97	2.40	3.3115 (19)	156
C8—H8A···Cg1ⁱⁱ	0.97	2.76	3.5026 (17)	134

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) −x+2, −y+1, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₁ClN₂O
M_r	270.71
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	11.2593 (4), 12.1848 (4), 9.5498 (3)
β (°)	103.053 (1)
V (Å³)	1276.31 (7)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.29
Crystal size (mm)	0.32 × 0.28 × 0.15

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	17039, 3172, 2578
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.669

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.111, 1.04
No. of reflections	3172
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.20

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C10–C15 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8B···O1ⁱ	0.97	2.40	3.3115 (19)	156
C8—H8A···Cg1ⁱⁱ	0.97	2.76	3.5026 (17)	134

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) −x+2, −y+1, −z+2.

Comparison of C═O and N—N bond lengths (Å) between the title compound and reported pyrazolone compounds. top

Compound	C═O	N—N
C₁₃H₁₄N₂O₂^a	1.313 (2)	1.395 (2)
C₁₉H₁₆N₂O₂^a	1.261 (2)	1.404 (2)
C₁₅H₁₂N₂O₂S^a	1.246 (2)	1.373 (2)
C₂₂H₁₅ClN₂O^c	1.228 (2)	1.405 (2)
C₁₆H₁₁N₃O^c	1.252 (3)	1.412 (4)
C₁₆H₁₀ClN₃O^c	1.250 (5)	1.420 (5)
C₁₀H₈N₄O₅^d	1.207 (3)	1.412 (2)
C₁₅H₁₁ClN₂O^e	1.213 (2)	1.404 (2)

Notes: (a) Holzer et al. (1999); (b) Bovio et al. (1974); (c) Ferretti et al. (1985); (d) Dardonville et al. (1998); (e) this work.

Acknowledgements

The authors gratefully acknowledge financial support by the Scientific Research Innovation Foundation for youth teachers of Zhoukou Normal University

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