PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of actaeInternational Union of Crystallographysearchopen accessarticle submissionjournal home pagethis article
 
Acta Crystallogr Sect E Struct Rep Online. 2008 November 1; 64(Pt 11): o2244.
Published online 2008 October 31. doi:  10.1107/S1600536808035034
PMCID: PMC2959600

(E)-4-[(1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)imino­meth­yl]phenyl 4-bromo­benzene­sulfonate

Abstract

In the title compound, C24H20BrN3O4S, the central benzene ring makes dihedral angles of 17.13 (13), 39.83 (13) and 58.37 (13)°, respectively, with the pyrazolone ring, the bromo­benzene ring and the terminal phenyl ring. In the crystal structure, the packing is stabilized by a weak non-classical inter­molecular C—H(...)O hydrogen bond which links the mol­ecules into a chain propagating in [100].

Related literature

For a related structure, see: Han et al. (2007 [triangle]). For general background, see: Kahwa et al. (1986 [triangle]); Klayman et al. (1979 [triangle]); Santos et al. (2001 [triangle]). For reference geometrical data: see: Allen et al. (1987 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-o2244-scheme1.jpg

Experimental

Crystal data

  • C24H20BrN3O4S
  • M r = 526.40
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o2244-efi1.jpg
  • a = 6.9959 (14) Å
  • b = 33.222 (6) Å
  • c = 10.218 (2) Å
  • β = 95.992 (3)°
  • V = 2361.9 (8) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 1.86 mm−1
  • T = 294 (2) K
  • 0.18 × 0.16 × 0.11 mm

Data collection

  • Bruker SMART APEX CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.693, T max = 0.815
  • 12151 measured reflections
  • 4174 independent reflections
  • 2506 reflections with I > 2σ(I)
  • R int = 0.058

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.107
  • S = 1.01
  • 4174 reflections
  • 300 parameters
  • H-atom parameters constrained
  • Δρmax = 0.28 e Å−3
  • Δρmin = −0.23 e Å−3

Data collection: SMART (Bruker, 1999 [triangle]); cell refinement: SAINT (Bruker, 1999 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808035034/hb2828sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808035034/hb2828Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The project was supported by the Foundation of the Education Department of Hebei Province (grant No. 606022).

supplementary crystallographic information

Comment

The synthesis and structure of Schiff bases have attracted much attention in biology and chemistry (Kahwa et al., 1986; Klayman et al., 1979). Many Schiff base derivatives have been synthesized and employed to develop protein and enzyme mimics (Santos et al., 2001). Among the large number of compounds, 4-amino-1,5-dimethyl-2-phenylpyrazol-3-one forms a variety of Schiff bases with aldehydes, and the synthesis and crystal structures of some of them, such as (E)-4-[(1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-ylimino) methyl]-phenyl 4-chlorobenzoate (Han et al., 2007) has been reported.

As part of an investigation of the potential coordination properties of Schiff bases that could function as ligands, we now report the synthesis and structure of the title compound, (I).

In the title molecule (Fig. 1), the pyrazolone ring (C14—C16/N1/N2/N3/O4) is nearly planar, with an r.m.s. deviation for fitted atoms of 0.029 Å. It makes a dihedral angle of 50.07 (13)° with its attached phenyl ring (C19—C24). The central benzene ring (C7—C13/O3) is almost planar, with an r.m.s. deviation for fitted atoms of 0.040Å. This group makes dihedral angles of 17.13 (13)°, 39.83 (13)° and 58.37 (13)°, respectively, with the the pyrazolone ring (C14—C16/N1/N2/N3/O4), the terminal C1—C6 benzene ring and the terminal C19—C24 phenyl ring. Otherwise, all bond lengths and angles are within their normal ranges (Allen et al., 1987).

In the crystal, the packing is stabilized by a weak, non-classical intermolecular C17—H17A···O4 hydrogen bond that links molecules into one-dimensional extended chains running along the a axis (Table 1, Fig. 2).

Experimental

An anhydrous ethanol solution (50 ml) of 4-formylphenyl 4-bromobenzenesulfonate (3.41 g, 10 mmol) was added to an anhydrous ethanol solution (50 ml) of 4-amino-1,5-dimethyl-2-phenylpyrazol-3-one (2.03 g, 10 mmol) and the mixture stirred at 350 K for 3 h under N2, giving a yellow precipitate. The product was isolated, recrystallized from acetonitrile, and then dried in a vacuum to give pure compound (I) in 87% yield. Yellow blocks of (I) were obtained by slow evaporation of an acetonitrile solution.

Refinement

The H atoms were included in calculated positions (C—H = 0.93–0.96Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C).

Figures

Fig. 1.
The molecular structure of (I) with displacement ellipsoids for non-H atoms drawn at the 30% probability level.
Fig. 2.
Packing diagram for (I), with H bonds drawn as dashed lines.

Crystal data

C24H20BrN3O4SF(000) = 1072
Mr = 526.40Dx = 1.480 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 1963 reflections
a = 6.9959 (14) Åθ = 2.9–25.2°
b = 33.222 (6) ŵ = 1.86 mm1
c = 10.218 (2) ÅT = 294 K
β = 95.992 (3)°Block, yellow
V = 2361.9 (8) Å30.18 × 0.16 × 0.11 mm
Z = 4

Data collection

Bruker SMART APEX CCD area-detector diffractometer4174 independent reflections
Radiation source: fine-focus sealed tube2506 reflections with I > 2σ(I)
graphiteRint = 0.058
[var phi] and ω scansθmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −8→8
Tmin = 0.693, Tmax = 0.815k = −39→27
12151 measured reflectionsl = −12→10

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.107w = 1/[σ2(Fo2) + (0.0386P)2 + 1.1353P] where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max = 0.001
4174 reflectionsΔρmax = 0.28 e Å3
300 parametersΔρmin = −0.23 e Å3
0 restraintsExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0031 (5)

Special details

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 > 2σ(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)

xyzUiso*/Ueq
Br1−0.44278 (7)0.221319 (15)−0.16276 (5)0.0730 (2)
S10.32046 (15)0.32822 (3)−0.18138 (10)0.0519 (3)
N10.0354 (4)0.49730 (9)0.2384 (3)0.0428 (8)
N2−0.1008 (4)0.56730 (9)0.4793 (3)0.0424 (8)
N30.0680 (4)0.58680 (9)0.4468 (3)0.0413 (8)
O10.4033 (4)0.31657 (9)−0.2973 (3)0.0710 (9)
O20.4292 (4)0.32724 (8)−0.0550 (3)0.0649 (8)
O30.2468 (4)0.37319 (7)−0.2123 (2)0.0557 (7)
O40.3126 (3)0.57085 (8)0.3161 (3)0.0523 (7)
C10.0241 (6)0.29604 (12)−0.0562 (4)0.0516 (10)
H10.08060.30800.02060.062*
C2−0.1397 (6)0.27304 (12)−0.0533 (4)0.0580 (11)
H2−0.19260.26940.02570.070*
C3−0.2254 (6)0.25539 (12)−0.1669 (4)0.0515 (10)
C4−0.1490 (7)0.26142 (13)−0.2856 (4)0.0638 (12)
H4−0.20870.2502−0.36260.077*
C50.0158 (6)0.28417 (13)−0.2892 (4)0.0590 (11)
H50.06740.2880−0.36850.071*
C60.1050 (5)0.30142 (11)−0.1744 (3)0.0421 (9)
C70.2344 (6)0.40100 (11)−0.1067 (4)0.0450 (10)
C80.0584 (6)0.40745 (11)−0.0611 (4)0.0470 (10)
H8−0.04790.3923−0.09350.056*
C90.0417 (5)0.43669 (11)0.0336 (4)0.0471 (10)
H9−0.07660.44120.06490.057*
C100.2019 (5)0.45956 (11)0.0826 (4)0.0429 (9)
C110.3780 (5)0.45208 (12)0.0337 (4)0.0534 (11)
H110.48560.46700.06530.064*
C120.3946 (6)0.42264 (12)−0.0617 (4)0.0549 (11)
H120.51190.4178−0.09410.066*
C130.1877 (5)0.49231 (11)0.1787 (4)0.0463 (10)
H130.29080.50980.19670.056*
C140.0223 (5)0.52968 (10)0.3248 (3)0.0373 (9)
C150.1548 (5)0.56282 (11)0.3545 (3)0.0384 (9)
C16−0.1307 (5)0.53488 (11)0.3982 (4)0.0395 (9)
C17−0.3093 (5)0.50989 (12)0.3944 (4)0.0570 (11)
H17A−0.41940.52640.36850.086*
H17B−0.32010.49880.48010.086*
H17C−0.30310.48840.33220.086*
C18−0.2542 (5)0.59204 (12)0.5268 (4)0.0584 (12)
H18A−0.33510.60260.45300.088*
H18B−0.19790.61390.57880.088*
H18C−0.32970.57580.57960.088*
C190.1734 (5)0.61215 (11)0.5422 (4)0.0405 (9)
C200.2802 (5)0.64372 (12)0.4972 (4)0.0512 (10)
H200.27880.64860.40750.061*
C210.3887 (6)0.66770 (13)0.5880 (5)0.0652 (12)
H210.46300.68840.55860.078*
C220.3878 (7)0.66132 (14)0.7211 (5)0.0707 (13)
H220.45910.67780.78140.085*
C230.2799 (7)0.63016 (14)0.7642 (5)0.0719 (13)
H230.27890.62580.85400.086*
C240.1737 (6)0.60533 (12)0.6761 (4)0.0568 (11)
H240.10280.58420.70630.068*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.0799 (4)0.0750 (4)0.0635 (3)−0.0191 (3)0.0040 (2)0.0108 (2)
S10.0520 (7)0.0551 (7)0.0491 (7)0.0086 (5)0.0076 (5)−0.0027 (5)
N10.0394 (19)0.0448 (19)0.044 (2)0.0047 (14)0.0013 (16)0.0025 (15)
N20.0279 (17)0.051 (2)0.050 (2)0.0043 (15)0.0134 (14)0.0036 (16)
N30.0293 (17)0.048 (2)0.048 (2)−0.0008 (14)0.0101 (15)0.0016 (15)
O10.068 (2)0.076 (2)0.075 (2)0.0053 (16)0.0348 (17)−0.0107 (16)
O20.0584 (18)0.069 (2)0.063 (2)0.0112 (15)−0.0128 (15)0.0004 (15)
O30.080 (2)0.0478 (17)0.0394 (17)0.0059 (14)0.0052 (14)0.0025 (13)
O40.0341 (15)0.0641 (18)0.0611 (19)−0.0074 (13)0.0166 (13)−0.0066 (14)
C10.063 (3)0.058 (3)0.033 (2)0.007 (2)0.003 (2)−0.0026 (18)
C20.072 (3)0.071 (3)0.033 (2)−0.001 (2)0.015 (2)0.003 (2)
C30.056 (3)0.050 (3)0.048 (3)0.008 (2)0.000 (2)0.0074 (19)
C40.077 (3)0.076 (3)0.037 (3)−0.013 (3)−0.003 (2)−0.004 (2)
C50.069 (3)0.075 (3)0.033 (2)−0.004 (2)0.008 (2)0.000 (2)
C60.049 (2)0.044 (2)0.033 (2)0.0098 (18)0.0056 (18)0.0027 (17)
C70.054 (3)0.040 (2)0.041 (2)0.002 (2)0.008 (2)0.0055 (18)
C80.047 (2)0.053 (3)0.041 (2)−0.0049 (19)−0.0005 (19)0.0059 (19)
C90.046 (2)0.050 (2)0.047 (2)0.006 (2)0.0109 (19)0.005 (2)
C100.043 (2)0.040 (2)0.046 (2)0.0046 (18)0.0061 (19)0.0056 (18)
C110.044 (2)0.054 (3)0.064 (3)−0.009 (2)0.009 (2)−0.006 (2)
C120.046 (3)0.055 (3)0.066 (3)0.003 (2)0.015 (2)−0.001 (2)
C130.039 (2)0.050 (2)0.051 (3)0.0012 (18)0.007 (2)0.0028 (19)
C140.030 (2)0.041 (2)0.041 (2)0.0020 (17)0.0004 (17)0.0061 (17)
C150.030 (2)0.046 (2)0.039 (2)0.0096 (18)0.0053 (17)0.0072 (17)
C160.029 (2)0.042 (2)0.047 (2)0.0031 (17)0.0022 (18)0.0102 (18)
C170.037 (2)0.063 (3)0.072 (3)−0.003 (2)0.008 (2)0.005 (2)
C180.038 (2)0.075 (3)0.065 (3)0.011 (2)0.018 (2)0.002 (2)
C190.035 (2)0.038 (2)0.049 (3)0.0077 (17)0.0058 (18)0.0037 (18)
C200.053 (3)0.053 (3)0.049 (3)0.007 (2)0.011 (2)0.003 (2)
C210.064 (3)0.054 (3)0.078 (4)−0.015 (2)0.010 (3)−0.004 (2)
C220.076 (3)0.066 (3)0.068 (4)−0.017 (3)−0.003 (3)−0.014 (3)
C230.091 (4)0.075 (3)0.047 (3)−0.007 (3)−0.003 (3)−0.002 (2)
C240.062 (3)0.056 (3)0.051 (3)−0.006 (2)0.003 (2)0.007 (2)

Geometric parameters (Å, °)

Br1—C31.900 (4)C9—C101.403 (5)
S1—O11.425 (3)C9—H90.9300
S1—O21.429 (3)C10—C111.399 (5)
S1—O31.601 (3)C10—C131.475 (5)
S1—C61.758 (4)C11—C121.394 (5)
N1—C131.292 (4)C11—H110.9300
N1—C141.401 (4)C12—H120.9300
N2—C161.362 (4)C13—H130.9300
N2—N31.416 (4)C14—C161.380 (5)
N2—C181.474 (4)C14—C151.451 (5)
N3—C151.418 (4)C16—C171.497 (5)
N3—C191.433 (5)C17—H17A0.9600
O3—C71.430 (4)C17—H17B0.9600
O4—C151.239 (4)C17—H17C0.9600
C1—C21.380 (5)C18—H18A0.9600
C1—C61.398 (5)C18—H18B0.9600
C1—H10.9300C18—H18C0.9600
C2—C31.381 (5)C19—C241.386 (5)
C2—H20.9300C19—C201.394 (5)
C3—C41.390 (5)C20—C211.387 (6)
C4—C51.382 (6)C20—H200.9300
C4—H40.9300C21—C221.378 (6)
C5—C61.393 (5)C21—H210.9300
C5—H50.9300C22—C231.380 (6)
C7—C121.370 (5)C22—H220.9300
C7—C81.378 (5)C23—C241.380 (6)
C8—C91.385 (5)C23—H230.9300
C8—H80.9300C24—H240.9300
O1—S1—O2121.36 (18)C10—C11—H11119.5
O1—S1—O3103.89 (16)C7—C12—C11118.5 (4)
O2—S1—O3109.24 (15)C7—C12—H12120.7
O1—S1—C6108.71 (18)C11—C12—H12120.7
O2—S1—C6109.24 (17)N1—C13—C10121.7 (3)
O3—S1—C6102.77 (16)N1—C13—H13119.2
C13—N1—C14120.5 (3)C10—C13—H13119.2
C16—N2—N3107.3 (3)C16—C14—N1123.0 (3)
C16—N2—C18124.8 (3)C16—C14—C15107.8 (3)
N3—N2—C18118.4 (3)N1—C14—C15129.2 (3)
N2—N3—C15108.9 (3)O4—C15—N3123.2 (3)
N2—N3—C19119.4 (3)O4—C15—C14131.9 (3)
C15—N3—C19123.9 (3)N3—C15—C14104.9 (3)
C7—O3—S1119.9 (2)N2—C16—C14110.5 (3)
C2—C1—C6120.1 (4)N2—C16—C17121.9 (3)
C2—C1—H1120.0C14—C16—C17127.5 (4)
C6—C1—H1120.0C16—C17—H17A109.5
C1—C2—C3120.4 (4)C16—C17—H17B109.5
C1—C2—H2119.8H17A—C17—H17B109.5
C3—C2—H2119.8C16—C17—H17C109.5
C2—C3—C4120.0 (4)H17A—C17—H17C109.5
C2—C3—Br1120.8 (3)H17B—C17—H17C109.5
C4—C3—Br1119.1 (3)N2—C18—H18A109.5
C5—C4—C3119.9 (4)N2—C18—H18B109.5
C5—C4—H4120.0H18A—C18—H18B109.5
C3—C4—H4120.0N2—C18—H18C109.5
C4—C5—C6120.3 (4)H18A—C18—H18C109.5
C4—C5—H5119.8H18B—C18—H18C109.5
C6—C5—H5119.8C24—C19—C20120.2 (4)
C5—C6—C1119.2 (4)C24—C19—N3121.5 (3)
C5—C6—S1119.0 (3)C20—C19—N3118.2 (3)
C1—C6—S1121.7 (3)C21—C20—C19119.1 (4)
C12—C7—C8122.2 (4)C21—C20—H20120.5
C12—C7—O3118.7 (3)C19—C20—H20120.5
C8—C7—O3118.9 (4)C22—C21—C20120.9 (4)
C7—C8—C9119.3 (4)C22—C21—H21119.5
C7—C8—H8120.3C20—C21—H21119.5
C9—C8—H8120.3C21—C22—C23119.3 (4)
C8—C9—C10120.5 (4)C21—C22—H22120.4
C8—C9—H9119.8C23—C22—H22120.4
C10—C9—H9119.8C24—C23—C22121.1 (4)
C11—C10—C9118.5 (4)C24—C23—H23119.5
C11—C10—C13119.5 (3)C22—C23—H23119.5
C9—C10—C13122.0 (3)C23—C24—C19119.4 (4)
C12—C11—C10121.0 (4)C23—C24—H24120.3
C12—C11—H11119.5C19—C24—H24120.3
C16—N2—N3—C15−7.1 (4)C10—C11—C12—C7−0.1 (6)
C18—N2—N3—C15−155.2 (3)C14—N1—C13—C10−177.2 (3)
C16—N2—N3—C19−157.5 (3)C11—C10—C13—N1−171.6 (3)
C18—N2—N3—C1954.4 (4)C9—C10—C13—N111.5 (6)
O1—S1—O3—C7−152.2 (3)C13—N1—C14—C16−175.3 (3)
O2—S1—O3—C7−21.4 (3)C13—N1—C14—C155.1 (6)
C6—S1—O3—C794.5 (3)N2—N3—C15—O4−174.2 (3)
C6—C1—C2—C3−0.4 (6)C19—N3—C15—O4−25.4 (5)
C1—C2—C3—C4−1.3 (6)N2—N3—C15—C144.5 (4)
C1—C2—C3—Br1176.6 (3)C19—N3—C15—C14153.3 (3)
C2—C3—C4—C51.8 (6)C16—C14—C15—O4178.2 (4)
Br1—C3—C4—C5−176.2 (3)N1—C14—C15—O4−2.2 (6)
C3—C4—C5—C6−0.6 (7)C16—C14—C15—N3−0.4 (4)
C4—C5—C6—C1−1.1 (6)N1—C14—C15—N3179.2 (3)
C4—C5—C6—S1177.1 (3)N3—N2—C16—C146.9 (4)
C2—C1—C6—C51.6 (6)C18—N2—C16—C14152.4 (3)
C2—C1—C6—S1−176.6 (3)N3—N2—C16—C17−172.9 (3)
O1—S1—C6—C5−19.4 (4)C18—N2—C16—C17−27.4 (5)
O2—S1—C6—C5−153.8 (3)N1—C14—C16—N2176.3 (3)
O3—S1—C6—C590.3 (3)C15—C14—C16—N2−4.0 (4)
O1—S1—C6—C1158.8 (3)N1—C14—C16—C17−3.9 (6)
O2—S1—C6—C124.4 (4)C15—C14—C16—C17175.7 (3)
O3—S1—C6—C1−91.5 (3)N2—N3—C19—C2429.2 (5)
S1—O3—C7—C1286.2 (4)C15—N3—C19—C24−116.5 (4)
S1—O3—C7—C8−99.0 (4)N2—N3—C19—C20−152.1 (3)
C12—C7—C8—C9−0.1 (6)C15—N3—C19—C2062.2 (5)
O3—C7—C8—C9−174.7 (3)C24—C19—C20—C211.0 (5)
C7—C8—C9—C100.0 (6)N3—C19—C20—C21−177.7 (3)
C8—C9—C10—C110.0 (5)C19—C20—C21—C22−1.7 (6)
C8—C9—C10—C13176.9 (3)C20—C21—C22—C231.2 (7)
C9—C10—C11—C120.1 (6)C21—C22—C23—C240.1 (7)
C13—C10—C11—C12−177.0 (4)C22—C23—C24—C19−0.8 (7)
C8—C7—C12—C110.1 (6)C20—C19—C24—C230.3 (6)
O3—C7—C12—C11174.8 (3)N3—C19—C24—C23178.9 (4)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C17—H17A···O4i0.962.403.361 (5)176

Symmetry codes: (i) x−1, y, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB2828).

References

  • Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.
  • Bruker (1999). SMART and SAINT Bruker AXS Inc., Madison, Wisconsin, USA.
  • Han, J.-R., Zhen, X.-L., Tian, X., Li, F. & Liu, S.-X. (2007). Acta Cryst. E63, o4035.
  • Kahwa, I. A., Selbin, J., Hsieh, T. C.-Y. & Laine, R. A. (1986). Inorg. Chim. Acta, 118, 179–185.
  • Klayman, D. L., Bartosevich, J. F., Griffin, T. S., Mason, C. J. & Scovill, J. P. (1979). J. Med. Chem.22, 855–862. [PubMed]
  • Santos, M. L. P., Bagatin, I. A., Pereira, E. M. & Ferreira, A. M. D. C. (2001). J. Chem. Soc. Dalton Trans. pp. 838–844.
  • Sheldrick, G. M. (1996). SADABS University of Göttingen, Germany.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography