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Acta Crystallogr Sect E Struct Rep Online. 2008 December 1; 64(Pt 12): o2286–o2287.
Published online 2008 November 8. doi:  10.1107/S1600536808035939
PMCID: PMC2959927

Ethyl 2-[(E)-4-(dimethyl­amino)benzyl­idenehydrazino]-5-nitro­benzoate

Abstract

The title compound, C18H20N4O4, exists in the E configuration with respect to the C=N bond of the methyl­idine unit. The dihedral angle between the two benzene rings is 9.01 (6)°. An intra­molecular N—H(...)O hydrogen bond involving the benzoate unit generates an S(6) ring motif. In the crystal, the mol­ecules are linked by weak C—H(...)O inter­actions into infinite chains along the b axis. These chains are further connected into sheets parallel to the ab plane which are stacked approximately along the c axis. A C—H(...)π inter­action is also observed.

Related literature

For related literature on hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For background to the applications of hydrazones, see, for example: Barton et al. (1962 [triangle]); Bedia et al. (2006 [triangle]); Buu-Hoi et al. (1953 [triangle]); Paquette (1995 [triangle]); Rollas et al. (2002 [triangle]); Terzioglu & Gürsoy (2003 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-o2286-scheme1.jpg

Experimental

Crystal data

  • C18H20N4O4
  • M r = 356.38
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o2286-efi1.jpg
  • a = 10.8216 (4) Å
  • b = 15.9175 (6) Å
  • c = 10.4136 (4) Å
  • β = 107.091 (2)°
  • V = 1714.56 (11) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.10 mm−1
  • T = 100.0 (1) K
  • 0.44 × 0.41 × 0.31 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.957, T max = 0.970
  • 16368 measured reflections
  • 3929 independent reflections
  • 3275 reflections with I > 2σ(I)
  • R int = 0.029

Refinement

  • R[F 2 > 2σ(F 2)] = 0.038
  • wR(F 2) = 0.105
  • S = 1.04
  • 3929 reflections
  • 242 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.26 e Å−3
  • Δρmin = −0.27 e Å−3

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: SAINT (Bruker, 2005 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808035939/is2354sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808035939/is2354Isup2.hkl

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

Acknowledgments

This work is supported by the Department of Science and Technology (DST), Government of India, under grant No. SR/S2/LOP-17/2006. The authors also thank Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012.

supplementary crystallographic information

Comment

Hydrazine is widely used as a reagent in synthetic organic chemistry but is probably most frequently associated with the transformation of carbonyl-containing compounds to the corresponding hydrazones (Paquette, 1995). These are intermediates in the Wolff-Kishner reduction as well as many other reactions of synthetic utility, such as the Barton vinyl iodide preparation (Barton et al., 1962). Hydrazones have been demonstrated to possess antimicrobial, anticonvulsant, analgesic, antiinflammatory, antiplatelet, antitubercular, anticancer and antitumoral activities (Bedia et al., 2006; Rollas et al., 2002; Terzioglu & Gürsoy, 2003). Hydrazones possessing an azometine –NHN=CH– proton constitute an important class of compounds for new drug development. Therefore, many researchers have synthesized these compounds as target structures to evaluate their biological activities. These observations have been the guides for the development of new hydrazones that possess varied biological activities. Some synthesized hydrazide-hydrazones were reported to have lower toxicity than hydrazides because of the blockage of –NH2 group (Buu-Hoi et al., 1953). These findings further support the growing importance of the synthesis of hydrazide-hydrazones compounds.

Figure 1 shows the molecular structure of the title compound. The total molecule is not planar and exist in the E configuration with respect to the C═N bond of methylidine moiety. The dihedral angle between the two benzene rings is 9.01 (6)°. The methylidine is co-planar with the C1–C6 benzene ring [the most deviation of 0.044 (1) Å of atom C3] with the torsion angle N2–N1–C7–C6 = -179.18 (10)°. The dimethylamino group is slightly twisted from the plane C1–C6 ring as indicated by the torsions angle of C17–N3–C3–C4 = -6.57 (18)° and C18–N3–C3–C4 = -177.96 (12)°. The nitro group is slightly twisted from the C8–C13 benzene ring with the interplanar angle between the mean plane through N4/O1/O2/C11 and C8–C13 planes [8.17 (7)°]. The ethyl group is nearly perpendicularly attached to the benzoate unit which can be reflected by the torsion angle C14–O3–C15–C16 = 88.66 (13)°. An intramolecular N2—H1N2···O4 hydrogen bond generates an S(6) ring motif (Bernstein et al., 1995) (Fig. 1 and Table 1). Bond lengths and angles in the title compound are in normal ranges (Allen et al., 1987).

Figure 2 shows that the molecules are linked into infinite chains along the b axis through weak C7—H7A···O1 interaction (Table 1) and these chains are further connected through weak C—H···O interactions (Table 1) forming sheets parallel to the ab plane. These sheets are stacked approximately along the c axis (Fig. 3). The crystal is stabilized by intramolecular N—H···O hydrogen bond, weak C—H···O interactions (Table 1) and C—H···π interactions (Table 1); Cg1 is the centroid of the C1–C6 ring.

Experimental

The title compound was obtained by refluxing ethyl 2-hydrazinyl-5-nitrobenzoate (0.01 mol) and 4-(dimethylamino) benzaldehyde (0.01 mol) in ethanol (40 ml) by adding 3 drops of concentrated sulfuric acid for 8 hrs. Excess ethanol was removed from the reaction mixture under reduced pressure. The solid product obtained was filtered, washed with water and dried. Red single crystals of the title compound suitable for x-ray structure determination were grown by slow evaporation of an ethanol solution at room temperature (m.p. 439 K).

Refinement

H atom attached to N atom was located in a difference map and refined isotropically. The remaining H atoms were constrained in a riding motion approximation, with Caryl—H = 0.93, Cmethylene—H = 0.97 and Cmethyl—H = 0.96 Å. The Uiso(H) values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups. The highest residual electron density peak is located at 0.70 Å from C1 and the deepest hole is located at 0.64 Å from N4.

Figures

Fig. 1.
The asymmetric unit of (I), showing 50% probability displacement ellipsoids and the atomic numbering.
Fig. 2.
The crystal packing of (I), viewed along the a axis showing that the molecules are linked into infinite chains along the b axis. Hydrogen bonds are drawn as dashed lines.
Fig. 3.
The crystal packing of (I), viewed approximately along the c axis. Hydrogen bonds are drawn as dashed lines.

Crystal data

C18H20N4O4F000 = 752
Mr = 356.38Dx = 1.381 Mg m3
Monoclinic, P21/cMelting point: 439 K
Hall symbol: -P 2ybcMo Kα radiation λ = 0.71073 Å
a = 10.8216 (4) ÅCell parameters from 3929 reflections
b = 15.9175 (6) Åθ = 2.0–27.5º
c = 10.4136 (4) ŵ = 0.10 mm1
β = 107.091 (2)ºT = 100.0 (1) K
V = 1714.56 (11) Å3Block, red
Z = 40.44 × 0.41 × 0.31 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer3929 independent reflections
Radiation source: fine-focus sealed tube3275 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.029
Detector resolution: 8.33 pixels mm-1θmax = 27.5º
T = 100.0(1) Kθmin = 2.0º
ω scansh = −14→12
Absorption correction: multi-scan(SADABS; Bruker, 2005)k = −20→19
Tmin = 0.957, Tmax = 0.970l = −13→13
16368 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.038H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.105  w = 1/[σ2(Fo2) + (0.0493P)2 + 0.6489P] where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max = 0.001
3929 reflectionsΔρmax = 0.26 e Å3
242 parametersΔρmin = −0.27 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none

Special details

Experimental. The low-temperature data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.
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)

xyzUiso*/Ueq
O10.79559 (10)0.52119 (6)−0.07387 (11)0.0354 (3)
O20.69063 (9)0.41140 (6)−0.17045 (10)0.0304 (2)
O30.81387 (8)0.14041 (5)−0.00146 (9)0.0220 (2)
O40.93830 (9)0.11554 (6)0.20957 (9)0.0263 (2)
N11.11000 (9)0.28501 (7)0.47925 (10)0.0205 (2)
N21.03176 (10)0.24883 (7)0.36376 (10)0.0200 (2)
N31.51942 (11)0.31448 (7)1.07252 (11)0.0251 (3)
N40.77246 (10)0.44519 (7)−0.07681 (11)0.0233 (2)
C11.27580 (12)0.33820 (8)0.74183 (12)0.0211 (3)
H1A1.23080.38100.68680.025*
C21.36107 (12)0.35818 (8)0.86484 (12)0.0217 (3)
H2A1.37240.41410.89150.026*
C31.43165 (11)0.29502 (8)0.95126 (12)0.0199 (3)
C41.40814 (11)0.21103 (8)0.90855 (12)0.0205 (3)
H4A1.45110.16790.96410.025*
C51.32196 (11)0.19195 (8)0.78513 (12)0.0204 (3)
H5A1.30780.13600.75940.024*
C61.25546 (11)0.25480 (8)0.69791 (12)0.0190 (3)
C71.16926 (11)0.23101 (8)0.56787 (12)0.0200 (3)
H7A1.15630.17420.54770.024*
C80.97180 (11)0.29570 (8)0.25563 (12)0.0186 (2)
C90.89357 (11)0.25738 (8)0.13494 (12)0.0185 (2)
C100.82866 (11)0.30810 (8)0.02772 (12)0.0188 (2)
H10A0.77500.2839−0.05000.023*
C110.84340 (11)0.39425 (8)0.03584 (12)0.0200 (3)
C120.92453 (12)0.43263 (8)0.15043 (13)0.0227 (3)
H12A0.93620.49060.15310.027*
C130.98667 (12)0.38414 (8)0.25861 (13)0.0219 (3)
H13A1.03960.40970.33550.026*
C140.88536 (11)0.16499 (8)0.12145 (12)0.0197 (3)
C150.80366 (13)0.05029 (8)−0.02550 (13)0.0235 (3)
H15A0.88310.02330.02620.028*
H15B0.79260.0394−0.11990.028*
C160.69201 (16)0.01346 (9)0.01292 (16)0.0362 (4)
H16A0.6876−0.0459−0.00450.054*
H16B0.61320.0396−0.03890.054*
H16C0.70380.02300.10680.054*
C171.57956 (12)0.24807 (9)1.16534 (13)0.0243 (3)
H17A1.62590.21111.12300.036*
H17B1.51410.21691.19020.036*
H17C1.63850.27221.24420.036*
C181.53899 (13)0.40099 (8)1.11646 (13)0.0276 (3)
H18A1.56510.43341.05110.041*
H18B1.60510.40371.20120.041*
H18C1.45980.42331.12620.041*
H1N21.0273 (15)0.1942 (11)0.3542 (16)0.034 (4)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0480 (6)0.0165 (5)0.0349 (6)−0.0003 (4)0.0017 (5)0.0046 (4)
O20.0372 (5)0.0261 (5)0.0215 (5)−0.0018 (4)−0.0011 (4)0.0025 (4)
O30.0290 (4)0.0158 (4)0.0178 (4)−0.0011 (3)0.0017 (4)−0.0012 (3)
O40.0334 (5)0.0205 (5)0.0201 (5)−0.0013 (4)−0.0001 (4)0.0025 (4)
N10.0205 (5)0.0251 (5)0.0149 (5)−0.0033 (4)0.0039 (4)−0.0025 (4)
N20.0239 (5)0.0194 (5)0.0152 (5)−0.0029 (4)0.0036 (4)−0.0024 (4)
N30.0307 (6)0.0223 (6)0.0174 (5)−0.0018 (4)−0.0006 (4)0.0005 (4)
N40.0282 (5)0.0195 (5)0.0221 (6)0.0014 (4)0.0070 (4)0.0018 (4)
C10.0239 (6)0.0203 (6)0.0180 (6)0.0012 (5)0.0043 (5)0.0027 (5)
C20.0273 (6)0.0167 (6)0.0202 (6)−0.0015 (5)0.0057 (5)−0.0005 (5)
C30.0220 (6)0.0222 (6)0.0150 (6)−0.0018 (5)0.0047 (5)0.0006 (5)
C40.0233 (6)0.0196 (6)0.0182 (6)0.0015 (4)0.0054 (5)0.0038 (5)
C50.0239 (6)0.0181 (6)0.0198 (6)−0.0018 (5)0.0075 (5)−0.0005 (5)
C60.0199 (5)0.0214 (6)0.0163 (6)−0.0017 (4)0.0060 (5)−0.0002 (5)
C70.0221 (5)0.0198 (6)0.0190 (6)−0.0024 (5)0.0076 (5)−0.0019 (5)
C80.0186 (5)0.0216 (6)0.0166 (6)−0.0004 (4)0.0065 (5)−0.0006 (5)
C90.0198 (5)0.0188 (6)0.0172 (6)−0.0013 (4)0.0059 (5)−0.0006 (5)
C100.0215 (5)0.0196 (6)0.0154 (6)−0.0015 (4)0.0054 (5)−0.0015 (5)
C110.0228 (6)0.0194 (6)0.0179 (6)0.0014 (4)0.0063 (5)0.0026 (5)
C120.0270 (6)0.0171 (6)0.0244 (7)−0.0019 (5)0.0081 (5)−0.0026 (5)
C130.0246 (6)0.0218 (6)0.0185 (6)−0.0023 (5)0.0050 (5)−0.0045 (5)
C140.0204 (5)0.0206 (6)0.0172 (6)−0.0017 (4)0.0043 (5)−0.0012 (5)
C150.0338 (7)0.0145 (6)0.0197 (6)0.0004 (5)0.0042 (5)−0.0025 (5)
C160.0544 (9)0.0263 (7)0.0337 (8)−0.0135 (6)0.0218 (7)−0.0090 (6)
C170.0249 (6)0.0279 (7)0.0172 (6)0.0014 (5)0.0018 (5)0.0031 (5)
C180.0311 (7)0.0266 (7)0.0199 (7)−0.0030 (5)−0.0003 (5)−0.0031 (5)

Geometric parameters (Å, °)

O1—N41.2340 (14)C7—H7A0.9300
O2—N41.2316 (14)C8—C131.4162 (17)
O3—C141.3445 (14)C8—C91.4294 (16)
O3—C151.4548 (14)C9—C101.3896 (17)
O4—C141.2170 (15)C9—C141.4775 (17)
N1—C71.2861 (16)C10—C111.3803 (17)
N1—N21.3770 (14)C10—H10A0.9300
N2—C81.3476 (16)C11—C121.3973 (17)
N2—H1N20.874 (17)C12—C131.3682 (18)
N3—C31.3739 (15)C12—H12A0.9300
N3—C181.4469 (17)C13—H13A0.9300
N3—C171.4511 (16)C15—C161.499 (2)
N4—C111.4469 (16)C15—H15A0.9700
C1—C21.3779 (17)C15—H15B0.9700
C1—C61.4003 (17)C16—H16A0.9600
C1—H1A0.9300C16—H16B0.9600
C2—C31.4141 (17)C16—H16C0.9600
C2—H2A0.9300C17—H17A0.9600
C3—C41.4084 (17)C17—H17B0.9600
C4—C51.3817 (17)C17—H17C0.9600
C4—H4A0.9300C18—H18A0.9600
C5—C61.3999 (17)C18—H18B0.9600
C5—H5A0.9300C18—H18C0.9600
C6—C71.4509 (16)
C14—O3—C15116.37 (9)C11—C10—H10A119.8
C7—N1—N2113.34 (10)C9—C10—H10A119.8
C8—N2—N1121.31 (10)C10—C11—C12121.27 (11)
C8—N2—H1N2117.3 (11)C10—C11—N4118.87 (11)
N1—N2—H1N2120.9 (11)C12—C11—N4119.86 (11)
C3—N3—C18120.17 (11)C13—C12—C11119.34 (12)
C3—N3—C17120.11 (11)C13—C12—H12A120.3
C18—N3—C17119.16 (10)C11—C12—H12A120.3
O2—N4—O1122.76 (11)C12—C13—C8121.17 (11)
O2—N4—C11118.95 (10)C12—C13—H13A119.4
O1—N4—C11118.29 (11)C8—C13—H13A119.4
C2—C1—C6121.36 (11)O4—C14—O3122.77 (11)
C2—C1—H1A119.3O4—C14—C9124.77 (11)
C6—C1—H1A119.3O3—C14—C9112.45 (10)
C1—C2—C3121.09 (12)O3—C15—C16111.47 (11)
C1—C2—H2A119.5O3—C15—H15A109.3
C3—C2—H2A119.5C16—C15—H15A109.3
N3—C3—C4121.08 (11)O3—C15—H15B109.3
N3—C3—C2121.52 (11)C16—C15—H15B109.3
C4—C3—C2117.40 (11)H15A—C15—H15B108.0
C5—C4—C3120.82 (11)C15—C16—H16A109.5
C5—C4—H4A119.6C15—C16—H16B109.5
C3—C4—H4A119.6H16A—C16—H16B109.5
C4—C5—C6121.61 (11)C15—C16—H16C109.5
C4—C5—H5A119.2H16A—C16—H16C109.5
C6—C5—H5A119.2H16B—C16—H16C109.5
C5—C6—C1117.65 (11)N3—C17—H17A109.5
C5—C6—C7119.07 (11)N3—C17—H17B109.5
C1—C6—C7123.27 (11)H17A—C17—H17B109.5
N1—C7—C6122.92 (11)N3—C17—H17C109.5
N1—C7—H7A118.5H17A—C17—H17C109.5
C6—C7—H7A118.5H17B—C17—H17C109.5
N2—C8—C13120.55 (11)N3—C18—H18A109.5
N2—C8—C9120.92 (11)N3—C18—H18B109.5
C13—C8—C9118.53 (11)H18A—C18—H18B109.5
C10—C9—C8119.18 (11)N3—C18—H18C109.5
C10—C9—C14119.99 (11)H18A—C18—H18C109.5
C8—C9—C14120.79 (11)H18B—C18—H18C109.5
C11—C10—C9120.39 (11)
C7—N1—N2—C8−173.78 (11)N2—C8—C9—C14−5.29 (17)
C6—C1—C2—C30.22 (19)C13—C8—C9—C14173.76 (11)
C18—N3—C3—C4−177.96 (12)C8—C9—C10—C112.42 (17)
C17—N3—C3—C4−6.57 (18)C14—C9—C10—C11−175.19 (11)
C18—N3—C3—C21.74 (19)C9—C10—C11—C120.79 (18)
C17—N3—C3—C2173.13 (12)C9—C10—C11—N4−178.88 (11)
C1—C2—C3—N3178.24 (12)O2—N4—C11—C107.77 (17)
C1—C2—C3—C4−2.05 (18)O1—N4—C11—C10−173.19 (12)
N3—C3—C4—C5−178.50 (11)O2—N4—C11—C12−171.90 (11)
C2—C3—C4—C51.79 (18)O1—N4—C11—C127.14 (18)
C3—C4—C5—C60.30 (19)C10—C11—C12—C13−2.54 (19)
C4—C5—C6—C1−2.13 (18)N4—C11—C12—C13177.12 (11)
C4—C5—C6—C7178.08 (11)C11—C12—C13—C81.02 (19)
C2—C1—C6—C51.87 (18)N2—C8—C13—C12−178.82 (11)
C2—C1—C6—C7−178.35 (12)C9—C8—C13—C122.13 (18)
N2—N1—C7—C6−179.18 (10)C15—O3—C14—O4−0.73 (17)
C5—C6—C7—N1−176.20 (11)C15—O3—C14—C9178.13 (10)
C1—C6—C7—N14.02 (19)C10—C9—C14—O4−179.76 (12)
N1—N2—C8—C13−0.74 (17)C8—C9—C14—O42.67 (19)
N1—N2—C8—C9178.29 (10)C10—C9—C14—O31.40 (16)
N2—C8—C9—C10177.12 (11)C8—C9—C14—O3−176.17 (10)
C13—C8—C9—C10−3.83 (17)C14—O3—C15—C1688.66 (13)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H1N2···O40.875 (18)1.978 (17)2.6736 (14)135.6 (14)
C7—H7A···O1i0.932.493.3599 (16)156
C12—H12A···O4ii0.932.593.3961 (16)145
C16—H16C···O2iii0.962.593.5116 (19)162
C17—H17B···Cg1iii0.962.643.4629 (14)144

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IS2354).

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