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Acta Cryst. (2009). E65, o988-o989    [ doi:10.1107/S1600536809012458 ]

3-{1-[(2,4-Dinitrophenyl)hydrazino]ethylidene}-5-(1-methylpropyl)pyrrolidine-2,4-dione

D. Siegel, S. Merkel, M. Koch, F. Emmerling and I. Nehls

Abstract top

In the title compound, C16H19N5O6, two intramolecular N-H...O hydrogen bonds help to establish the conformation. In the crystal, intermolecular N-H...O links result in chains propagating in [010].

Comment top

The title compound is the condensation product of the Alternaria spp. mycotoxin tenuazonic acid and 2,4-dinitrophenylhydrazine. It is formed during the derivatization step of a novel HPLC-ESI multistage MS method for tenuazonic acid quantification in cereals (Siegel et al., 2009). While tenuazonic acid itself occurs as a non-crystallizable gum, the crystal structure of its copper salt has previously been reported (Dippenaar et al., 1977). For exemplary crystal structures of other 2,4-dinitrophenylhydrazones see Tameem et al., 2006, Monfared et al., 2007, Valente et al., 2008, Yin et al., 2008. The structure of the title compound is of particular interest, since solubilized tetramic acids and their hydrazones display a variety of tautomeric forms (Yamaguchi et al., 1976a,b, Nolte et al., 1980, Gelin et al., 1982, Royles, 1995, Siegel et al., 2009) (see Fig. 1). While the two rotameric groups I—II and III-IV (Fig. 1) may be differentiated using 1H-NMR, the tautomeric equilibria which are fast on the NMR timescale can not be characterized like that. Furthermore, although common NMR experiments allow for the differentiation of the two rotameric tautomers, the structural assignment of the predominant species is not possible. The presented crystal structure indicates that a six-membered ring involving an intramolecular hydrogen bond between the O5 and N4 is in fact favoured for this compound. On the basis of the presented crystal structure, it can also be assumed, that the thermodynamically favoured tautomer does not involve a double bond of N3 or N4 and thus is tautomer I (Fig. 1). Six N—H···O hydrogen bonds connect each molecule to four adjacent molecules, which are all screw images and span a length of four unit cells. As depicted in Fig. 3 these interactions result in indefinite chains along the b axis.

Related literature top

For the use of the title compound in instrumental analytical chemistry, see: Siegel et al. (2009). For the crystal structure of the tenuazonic copper(II) salt, see: Dippenaar et al. (1977). For the structures of other 2,4-dinitrophenylhydrazones, see: Tameem et al. (2006); Monfared et al. (2007); Valente et al. (2008); Yin et al. (2008). Solubilized tetramic acids and their hydrazones display a variety of tautomeric forms, see: Gelin et al. (1982); Nolte et al. (1980); Royles (1995); Yamaguchi et al. (1976a, 1976b). For the synthesis, see: Lebrun et al. (1988).

Experimental top

The tenuazonic acid natrium salt was supplied by the workgroup of Professor R. Faust (University of Kassel, Germany) by total synthesis from L-isoleucine according to a literature procedure (Lebrun et al., 1988). The title compound was synthesized by adding the tenuazonic acid natrium salt (1 eq.) to a 15 mM solution of 2,4-dinitrophenylhydrazine in 2 N HCl (2 eq.). After 30 minutes of shaking the precipitate was collected, washed with water, dissolved in ethyl acetate and dried with natrium sulfate. After evaporation of the solvent, a yellow powder was obtained, which was recrystallized from ethanol five times to obtain the title compound in analytical purity. For X-ray analysis yellow crystals of tenuazonic acid 2,4-dinitrophenylhydrazone were grown by solvent evaporation from ethanol at ambient temperature over a period of three weeks.

Refinement top

The hydrogen atoms were located in difference maps but positioned with idealized geometry and refined using the riding model, with N,C—H = 0.93–0.97 Å, and Uĩso~(H) = 1.2U~eq~(parent atom). Methyl groups (C14, C15, C16) were refined with Uĩso~(H) = 1.5U~eq~(parent atom).

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: CORINC (Dräger & Gattow, 1971); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Tautomeric equilibria of tetramic acid dinitrophenylhydrazones.
[Figure 2] Fig. 2. ORTEP representation of the title compound with atomic labeling, shown with 50% probability displacement ellipsoids.
[Figure 3] Fig. 3. View of the crystal packing of the title compound, projected down c. Infinite one-dimensional chains along the [010] direction are formed via strong hydrogen-bonding interactions (indicated by green dashed lines). The intramolecular hydrogen bonds and the isobutyl groups are omitted for clarity.
3-{1-[(2,4-Dinitrophenyl)hydrazino]ethylidene}-5-(1-methylpropyl)pyrrolidine- 2,4-dione top
Crystal data top
C16H19N5O6F(000) = 396
Mr = 377.36Dx = 1.480 Mg m−3
Monoclinic, P21Cu Kα radiation, λ = 1.54178 Å
Hall symbol: P 2ybCell parameters from 25 reflections
a = 10.671 (1) Åθ = 60–69°
b = 4.9387 (5) ŵ = 0.98 mm−1
c = 16.839 (2) ÅT = 193 K
β = 107.363 (4)°Needles, yellow
V = 846.98 (15) Å30.64 × 0.06 × 0.06 mm
Z = 2
Data collection top
Enraf–Nonius CAD-4
diffractometer		3103 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.025
graphiteθmax = 73.6°, θmin = 2.8°
ω/2θ scansh = −13→13
Absorption correction: ψ scan
(CORINC; Dräger & Gattow, 1971)		k = −5→6
Tmin = 0.78, Tmax = 0.94l = −20→20
3890 measured reflections3 standard reflections every 60 min
3282 independent reflections intensity decay: 2%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.039H-atom parameters constrained
wR(F2) = 0.111 w = 1/[σ2(Fo2) + (0.0778P)2 + 0.1634P]
where P = (Fo2 + 2Fc2)/3
S = 0.99(Δ/σ)max < 0.001
3282 reflectionsΔρmax = 0.24 e Å−3
247 parametersΔρmin = −0.21 e Å−3
1 restraintAbsolute structure: (Flack,1983)
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.1 (2)
Crystal data top
C16H19N5O6V = 846.98 (15) Å3
Mr = 377.36Z = 2
Monoclinic, P21Cu Kα radiation
a = 10.671 (1) ŵ = 0.98 mm−1
b = 4.9387 (5) ÅT = 193 K
c = 16.839 (2) Å0.64 × 0.06 × 0.06 mm
β = 107.363 (4)°
Data collection top
Enraf–Nonius CAD-4
diffractometer		3103 reflections with I > 2σ(I)
Absorption correction: ψ scan
(CORINC; Dräger & Gattow, 1971)		Rint = 0.025
Tmin = 0.78, Tmax = 0.94θmax = 73.6°
3890 measured reflections3 standard reflections every 60 min
3282 independent reflections intensity decay: 2%
Refinement top
R[F2 > 2σ(F2)] = 0.039H-atom parameters constrained
wR(F2) = 0.111Δρmax = 0.24 e Å−3
S = 0.99Δρmin = −0.21 e Å−3
3282 reflectionsAbsolute structure: (Flack,1983)
247 parametersFlack parameter: 0.1 (2)
1 restraint
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
xyzUiso*/Ueq
O10.28853 (17)1.4445 (4)0.18665 (10)0.0394 (4)
O20.38017 (15)1.3663 (4)0.31656 (10)0.0373 (4)
O3−0.1297 (2)0.5644 (5)0.06973 (11)0.0559 (5)
O4−0.07342 (18)0.9300 (4)0.01932 (9)0.0444 (4)
O50.43857 (13)0.4033 (3)0.54411 (8)0.0277 (3)
O60.13063 (14)0.7678 (4)0.66874 (9)0.0348 (4)
N10.29520 (16)1.3174 (4)0.24909 (10)0.0267 (4)
N2−0.06562 (18)0.7738 (4)0.07614 (11)0.0339 (4)
N30.27686 (16)1.0106 (4)0.39501 (10)0.0280 (4)
H3N0.35381.10870.40070.034*
N40.29331 (16)0.8153 (4)0.45682 (10)0.0266 (4)
H4N0.35840.69590.46270.032*
N50.39181 (16)0.3303 (4)0.66688 (9)0.0262 (4)
H5N0.45420.21580.68560.031*
C10.20134 (18)1.0983 (4)0.24520 (12)0.0230 (4)
C20.11472 (18)1.0434 (4)0.16609 (11)0.0254 (4)
H20.11751.14620.11900.030*
C30.02556 (19)0.8361 (5)0.15868 (12)0.0265 (4)
C40.01923 (18)0.6831 (4)0.22646 (12)0.0271 (4)
H4−0.04280.54040.21950.032*
C50.10350 (19)0.7399 (4)0.30371 (12)0.0266 (4)
H50.09840.63560.35000.032*
C60.19821 (17)0.9503 (4)0.31639 (11)0.0240 (4)
C70.23382 (17)0.8356 (4)0.51605 (11)0.0231 (4)
C80.27239 (16)0.6612 (4)0.58383 (11)0.0221 (4)
C90.37640 (18)0.4572 (4)0.59406 (11)0.0212 (4)
C100.30819 (18)0.4349 (4)0.71460 (11)0.0242 (4)
H100.25150.28600.72500.029*
C110.22234 (17)0.6447 (4)0.65454 (11)0.0246 (4)
C120.38790 (18)0.5633 (4)0.79844 (11)0.0253 (4)
H120.42820.73470.78600.030*
C130.4990 (3)0.3758 (6)0.84642 (14)0.0444 (6)
H13A0.46000.20300.85720.053*
H13B0.55520.33500.81060.053*
C140.5849 (3)0.4865 (7)0.92845 (14)0.0501 (7)
H14A0.53370.49850.96800.075*
H14B0.61650.66710.91970.075*
H14C0.65990.36560.95080.075*
C150.2971 (2)0.6350 (9)0.84970 (15)0.0578 (9)
H15A0.34480.74590.89740.087*
H15B0.26640.46860.86960.087*
H15C0.22160.73680.81520.087*
C160.12597 (18)1.0397 (4)0.50566 (12)0.0278 (4)
H16A0.05030.98650.45890.042*
H16B0.15721.21810.49450.042*
H16C0.09991.04760.55670.042*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0475 (9)0.0367 (10)0.0360 (8)−0.0111 (7)0.0159 (7)0.0053 (7)
O20.0333 (7)0.0348 (9)0.0376 (7)−0.0119 (7)0.0012 (6)0.0042 (7)
O30.0587 (11)0.0619 (14)0.0401 (9)−0.0337 (11)0.0039 (8)−0.0078 (9)
O40.0529 (9)0.0479 (11)0.0256 (7)−0.0039 (9)0.0015 (6)0.0023 (8)
O50.0263 (6)0.0311 (8)0.0265 (6)0.0058 (6)0.0092 (5)−0.0005 (6)
O60.0290 (7)0.0447 (10)0.0320 (7)0.0120 (7)0.0111 (5)−0.0006 (7)
N10.0266 (8)0.0226 (9)0.0316 (8)−0.0008 (7)0.0099 (6)0.0016 (7)
N20.0334 (9)0.0378 (12)0.0279 (8)−0.0041 (8)0.0053 (7)−0.0050 (8)
N30.0256 (7)0.0300 (10)0.0246 (8)−0.0046 (7)0.0020 (6)0.0053 (7)
N40.0250 (7)0.0276 (9)0.0260 (8)0.0049 (7)0.0059 (6)0.0050 (7)
N50.0311 (8)0.0242 (9)0.0226 (7)0.0071 (7)0.0073 (6)0.0004 (6)
C10.0219 (8)0.0195 (10)0.0277 (9)0.0018 (7)0.0075 (7)0.0015 (7)
C20.0262 (9)0.0244 (10)0.0257 (9)0.0029 (8)0.0082 (7)0.0012 (8)
C30.0236 (8)0.0290 (11)0.0257 (9)0.0016 (8)0.0053 (7)−0.0028 (8)
C40.0239 (9)0.0249 (11)0.0336 (9)−0.0028 (8)0.0104 (7)−0.0028 (8)
C50.0280 (9)0.0253 (11)0.0276 (9)−0.0003 (8)0.0099 (7)0.0031 (8)
C60.0210 (8)0.0254 (11)0.0254 (8)0.0021 (7)0.0064 (7)−0.0011 (8)
C70.0204 (8)0.0213 (9)0.0239 (8)−0.0048 (7)0.0009 (6)−0.0041 (7)
C80.0200 (8)0.0209 (10)0.0228 (8)0.0004 (7)0.0025 (6)−0.0032 (7)
C90.0218 (8)0.0175 (10)0.0221 (8)−0.0014 (7)0.0030 (6)−0.0026 (7)
C100.0254 (8)0.0240 (10)0.0237 (8)−0.0011 (8)0.0083 (7)−0.0014 (8)
C110.0206 (8)0.0266 (11)0.0244 (8)−0.0004 (8)0.0031 (6)−0.0037 (8)
C120.0274 (9)0.0266 (11)0.0209 (8)0.0008 (8)0.0056 (7)−0.0016 (7)
C130.0492 (13)0.0449 (16)0.0314 (10)0.0177 (12)0.0005 (9)0.0001 (10)
C140.0420 (13)0.071 (2)0.0305 (11)0.0011 (13)−0.0001 (9)0.0054 (12)
C150.0391 (12)0.102 (3)0.0311 (11)0.0168 (15)0.0088 (9)−0.0188 (14)
C160.0229 (8)0.0242 (11)0.0330 (10)0.0017 (8)0.0032 (7)0.0003 (8)
Geometric parameters (Å, °) top
O1—N11.208 (2)C5—H50.9500
O2—N11.248 (2)C7—C81.391 (3)
O3—N21.227 (3)C7—C161.500 (3)
O4—N21.212 (3)C8—C111.445 (3)
O5—C91.246 (2)C8—C91.470 (3)
O6—C111.235 (2)C10—C111.544 (3)
N1—C11.463 (3)C10—C121.550 (2)
N2—C31.472 (2)C10—H101.0000
N3—C61.372 (2)C12—C151.519 (3)
N3—N41.391 (2)C12—C131.531 (3)
N3—H3N0.9328C12—H121.0000
N4—C71.336 (2)C13—C141.514 (3)
N4—H4N0.8942C13—H13A0.9900
N5—C91.343 (2)C13—H13B0.9900
N5—C101.462 (2)C14—H14A0.9800
N5—H5N0.8585C14—H14B0.9800
C1—C21.403 (3)C14—H14C0.9800
C1—C61.413 (3)C15—H15A0.9800
C2—C31.378 (3)C15—H15B0.9800
C2—H20.9500C15—H15C0.9800
C3—C41.387 (3)C16—H16A0.9800
C4—C51.372 (3)C16—H16B0.9800
C4—H40.9500C16—H16C0.9800
C5—C61.421 (3)
O1—N1—O2121.99 (18)N5—C9—C8108.01 (16)
O1—N1—C1118.93 (16)N5—C10—C11102.55 (14)
O2—N1—C1119.08 (16)N5—C10—C12112.72 (16)
O4—N2—O3124.19 (18)C11—C10—C12112.29 (17)
O4—N2—C3118.86 (19)N5—C10—H10109.7
O3—N2—C3116.95 (19)C11—C10—H10109.7
C6—N3—N4118.40 (17)C12—C10—H10109.7
C6—N3—H3N118.5O6—C11—C8129.87 (19)
N4—N3—H3N111.9O6—C11—C10123.60 (17)
C7—N4—N3121.63 (17)C8—C11—C10106.53 (16)
C7—N4—H4N119.6C15—C12—C13111.46 (19)
N3—N4—H4N117.4C15—C12—C10110.08 (17)
C9—N5—C10114.12 (17)C13—C12—C10111.18 (18)
C9—N5—H5N120.9C15—C12—H12108.0
C10—N5—H5N124.4C13—C12—H12108.0
C2—C1—C6122.02 (18)C10—C12—H12108.0
C2—C1—N1115.71 (16)C14—C13—C12115.2 (2)
C6—C1—N1122.27 (16)C14—C13—H13A108.5
C3—C2—C1118.11 (18)C12—C13—H13A108.5
C3—C2—H2120.9C14—C13—H13B108.5
C1—C2—H2120.9C12—C13—H13B108.5
C2—C3—C4122.15 (17)H13A—C13—H13B107.5
C2—C3—N2119.00 (18)C13—C14—H14A109.5
C4—C3—N2118.85 (19)C13—C14—H14B109.5
C5—C4—C3119.32 (19)H14A—C14—H14B109.5
C5—C4—H4120.3C13—C14—H14C109.5
C3—C4—H4120.3H14A—C14—H14C109.5
C4—C5—C6121.87 (18)H14B—C14—H14C109.5
C4—C5—H5119.1C12—C15—H15A109.5
C6—C5—H5119.1C12—C15—H15B109.5
N3—C6—C1122.96 (18)H15A—C15—H15B109.5
N3—C6—C5120.45 (17)C12—C15—H15C109.5
C1—C6—C5116.52 (17)H15A—C15—H15C109.5
N4—C7—C8118.42 (17)H15B—C15—H15C109.5
N4—C7—C16118.82 (17)C7—C16—H16A109.5
C8—C7—C16122.73 (17)C7—C16—H16B109.5
C7—C8—C11128.27 (17)H16A—C16—H16B109.5
C7—C8—C9123.28 (16)C7—C16—H16C109.5
C11—C8—C9108.45 (16)H16A—C16—H16C109.5
O5—C9—N5124.91 (18)H16B—C16—H16C109.5
O5—C9—C8127.06 (17)
C6—N3—N4—C7−105.2 (2)N4—C7—C8—C11−179.71 (18)
O1—N1—C1—C23.8 (3)C16—C7—C8—C11−1.4 (3)
O2—N1—C1—C2−175.79 (18)N4—C7—C8—C90.7 (3)
O1—N1—C1—C6−176.46 (19)C16—C7—C8—C9178.93 (17)
O2—N1—C1—C64.0 (3)C10—N5—C9—O5179.12 (18)
C6—C1—C2—C3−0.8 (3)C10—N5—C9—C8−2.4 (2)
N1—C1—C2—C3179.01 (17)C7—C8—C9—O5−3.5 (3)
C1—C2—C3—C40.1 (3)C11—C8—C9—O5176.79 (19)
C1—C2—C3—N2−179.57 (18)C7—C8—C9—N5178.00 (18)
O4—N2—C3—C2−10.8 (3)C11—C8—C9—N5−1.7 (2)
O3—N2—C3—C2169.4 (2)C9—N5—C10—C115.1 (2)
O4—N2—C3—C4169.5 (2)C9—N5—C10—C12−115.88 (19)
O3—N2—C3—C4−10.3 (3)C7—C8—C11—O64.6 (4)
C2—C3—C4—C50.5 (3)C9—C8—C11—O6−175.7 (2)
N2—C3—C4—C5−179.82 (18)C7—C8—C11—C10−174.97 (18)
C3—C4—C5—C6−0.5 (3)C9—C8—C11—C104.7 (2)
N4—N3—C6—C1−162.77 (18)N5—C10—C11—O6174.63 (19)
N4—N3—C6—C520.5 (3)C12—C10—C11—O6−64.1 (2)
C2—C1—C6—N3−176.16 (18)N5—C10—C11—C8−5.7 (2)
N1—C1—C6—N34.1 (3)C12—C10—C11—C8115.53 (17)
C2—C1—C6—C50.7 (3)N5—C10—C12—C15−172.8 (2)
N1—C1—C6—C5−179.02 (17)C11—C10—C12—C1572.0 (3)
C4—C5—C6—N3176.88 (19)N5—C10—C12—C13−48.8 (2)
C4—C5—C6—C1−0.1 (3)C11—C10—C12—C13−164.01 (19)
N3—N4—C7—C8−168.70 (16)C15—C12—C13—C14−58.2 (3)
N3—N4—C7—C1613.0 (3)C10—C12—C13—C14178.5 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H3N···O20.931.992.630 (2)125
N4—H4N···O50.892.002.710 (2)135
N3—H3N···O5i0.932.362.949 (2)121
N4—H4N···O5i0.892.432.898 (2)113
N5—H5N···O2ii0.862.483.293 (2)159
Symmetry codes: (i) −x+1, y+1/2, −z+1; (ii) −x+1, y−3/2, −z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H3N···O20.931.992.630 (2)125
N4—H4N···O50.892.002.710 (2)135
N3—H3N···O5i0.932.362.949 (2)121
N4—H4N···O5i0.892.432.898 (2)113
N5—H5N···O2ii0.862.483.293 (2)159
Symmetry codes: (i) −x+1, y+1/2, −z+1; (ii) −x+1, y−3/2, −z+1.
references
References top

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