research communications
E)-4-hydroxy-6-methyl-3-{1-[2-(4-nitrophenyl)hydrazinylidene]ethyl}-2H-pyran-2-one
of (aDepartment of Chemistry, Centre for Advanced Studies in Chemistry, Panjab University, Chandigarh 160 014, India, and bDepartment of Chemistry, DAV University Jalandhar, Jalandhar 144 001, Punjab, India
*Correspondence e-mail: gkumar@pu.ac.in, rkataria@pu.ac.in
The title compound, C14H13N3O5 (HMNP), was synthesized by the simple condensation of p-nitrophenylhydrazine with dehydroacetic acid (DHA) in a 1:1 molar ratio in ethanol. HMNP has been characterized by using FT–IR, 1H and 13C NMR and UV–Vis spectroscopic and single-crystal X-ray diffraction techniques. The crystal packing reveals strong hydrogen bonds between the NH group and the carbonyl O atom of dihydropyranone moiety, forming chains along [101]. The thermal stability of the synthesized compound was confirmed by thermogravimetric analysis and it was found to be stable up to 513 K. The UV–Vis spectrum shows the presence of a strong band at λmax 394 nm. 1H NMR and single-crystal X-ray analyses confirmed the presence of the enol form of the ligand and dominance over the keto form. The crystal studied was a non-merohedral twin with the refined ratio of the twin components being 0.3720 (19):0.6280 (19).
Keywords: crystal structure; HMNP; dehydroacetic acid; hydrogen bonding; thermal stability.
CCDC reference: 1515036
1. Chemical context
For the last several decades, ; Chen et al., 2008). A number of and have been utilized for the synthesis of (Zheng et al., 2009; Hussain et al., 2014). However, there are only a few reports where dehydroacetic acid (DHA) has been used for the preparation of for various applications (Liu et al., 1991; Luo et al., 1995). In some cases, DHA-based are used for the synthesis of metal complexes, leading to their utilization in various biomedical applications due to their antifungal, antibacterial, antimalarial and anticancer activities (Chan & Wong, 1995; Erkkila et al., 1999; Ganjali et al., 2007; Gupta & Sutar, 2008). In general, the compounds are formed via a condensation product of hydrazine and the respective aldehyde or ketone in a 1:1 molar ratio. Structurally, a Schiff base (also known as an imine or azomethine) is a nitrogen analogue of an aldehyde or ketone in which the carbonyl group (C=O) has been replaced by an imine or azomethine group.
have remained an important and popular area of research for the scientific community due to their simple synthesis, versatility and extensive range of applications (Cozzi, 2004The reaction between p-nitrophenylhydrazine and dehydroacetic acid (DHA) in a 1:1 molar ratio in distilled ethanol afforded the title compound within 4 h. We report herein on its characterization by FT–IR, 1H and 13C NMR and UV–Vis spectroscopic and single-crystal X-ray diffraction techniques.
2. Structural commentary
The molecular structure of the title compound is shown in Fig. 1. The dihedral angle between the pyran (O2/C9–C13) and benzene (C1–C6) rings is 12.9 (1)°. The approximate planarity of the entire molecule maybe influenced by an intramolecular O1—H1⋯N3 hydrogen bond, which forms an S(6) ring.
3. Supramolecular features
The crystal packing features strong N2—H2⋯O3i hydrogen bonds between the NH group and the Ocarbonyl atom of the DHA moiety of symmetry-related molecules, creating infinite chains along [101] (see Table 1 for symmetry code). This Ocarbonyl atom is also weakly hydrogen bonded to a symmetry-related hydrogen atom (C5–H5⋯O3i), forming a bifurcated N—H,C—H⋯O hydrogen bond (Fig. 2). In a similar fashion, the O2 atom of the pyran ring forms a weak hydrogen bond to the methyl hydrogen of an adjacent molecule (C7—H7A⋯O2i). The chains are arranged in a herringbone pattern in the three-dimensional structure (Fig. 3).
4. Hirshfeld surface analysis
The Hirshfeld surface was mapped with dnorm to visualize the intermolecular interactions and 2-D fingerprint plots were generated using Crystal Explorer (Wolff et al., 2012) (Fig. 4).
5. Spectroscopic and TG analysis
The FT–IR spectrum of the title compound shows a characteristic peak at 1687 cm−1 which has been consigned for νC=N, whereas the broad signal at 3280 cm−1 (νO–H) indicates the presence of a phenolic group. The 1H NMR spectrum display a singlet at δ 15.23 ppm, which clearly indicates the dominance of the enol form of the title compound over the keto form. The absorption spectra for HMNP was recorded in C2H5OH, and λmax was observed at 394 nm, which is ascribed to the π→π* or n→π* transition of the C=O or C=N group. To probe the thermal stability of HMNP, thermogravimetric analysis (TGA) was undertaken and it was found that HMNP is stable to 513 K.
6. Synthesis and crystallization
Materials and methods: p-Nitrophenylhydrazine and dehydroacetic acid were of analytical grade and purchased from Spectrochem and Merck (India), respectively, and used as received. However, analytical grade solvents were purified wherever necessary as per as the standard literature method (Perrin et al., 1980). The FT–IR spectra were recorded with a Perkin–Elmer FTIR–2000 spectrometer. The NMR spectroscopic measurements were carried out with a JEOL AL-400 MHz spectrometer. The thermogravimetric analysis (TGA) measurement was performed on an SDT Q600 (V20.9 Build 20) instrument (Artisan Technology Group, Champaign, IL) under N2 atmosphere with a heating rate of 10 K min−1. The absorbance spectrum was recorded on a JASCO V-530 UV/vis Spectrophotometer.
Synthesis of (E)-4-hydroxy-6-methyl-3-(1-(2-(4-nitrophenyl) hydrazone) ethyl) 2-H-pyran-2-one (HMNP):
HMNP was synthesized by the reaction of DHA (0.56g, 0.003 mol) with para-nitrophenylhydrazine (0.45g, 0.003 mol) in distilled ethanol (15 mL) under reflux condition at 353 K for 3 h (Fig. 5). The progress of the reaction was monitored by thin layer (TLC). After completion of the reaction, the reaction mixture was cooled to room temperature and the yellow crystalline precipitate was filtrated off and washed with cold ethanol and dried [yield: 0.728g (80%)]. Crystals suitable for single crystal X-ray analysis were obtained by the slow evaporation of a THF solution of HMNP for 7–8 d.
FT–IR (selected peaks): 3280 (O–H), 3088 (N–H), 1687 (C=O), 1646 (C=N) cm−1. [λmax, nm, C2H5OH (∊, M−1 cm−1)]: 394 (150), 274 (sh, 525). 1H NMR (CDCl3, 400 MHz): δ (ppm): 15.23 (s, 1H, He), 8.23–8.21 (d, 2H, Ha), 7.34 (1s, 1H, Hc), 6.94–6.93 (d, 2H, Hb), 5.93 (s, 1H, Hf), 2.67 (1s, 3H, Hg), 2.25 (1s, 3H, Hd). 13C NMR (DMSO-d6, 100 MHz): δ 176.4 (C8), 167.1 (C12), 163.1 (C10), 150.2 (C7), 139.5 (C4), 125.8 (C1), 111.3 (C2), 103.3 (C3), 96.4 (C9), 79.1 (C5), 78.7 (C11), 78.3 (C6).
7. Refinement
Crystal data, data collection and structure . The NH and OH hydrogen atoms were located in a difference-Fourier map and freely refined. The C-bound H atoms were included in calculated positions and treated as riding atoms: C—H = 0.93–0.96 Å, O—H= 0.82 Å with Uiso(H) = 1.2Ueq(C) and Uiso(H) = 1.5Ueq(Cmethyl). The crystal studied was a non-merohedral twin with the refined ratio of the twin components being 0.3720 (19):0.6280 (19) using twin matrix (0 0) (0 0) (0.265 0 ).
details are summarized in Table 2Supporting information
CCDC reference: 1515036
https://doi.org/10.1107/S2056989017000639/lh5834sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017000639/lh5834Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989017000639/lh5834Isup3.cdx
Supporting information file. DOI: https://doi.org/10.1107/S2056989017000639/lh5834Isup4.cml
Data collection: APEX2 (Bruker, 2010); cell
SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SHELXS2013 (Sheldrick 2008); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015); molecular graphics: X-SEED (Barbour 2001); software used to prepare material for publication: publCIF (Westrip 2010).C14H13N3O5 | F(000) = 632 |
Mr = 303.27 | Dx = 1.460 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 6.9633 (3) Å | Cell parameters from 9944 reflections |
b = 19.5008 (9) Å | θ = 2.3–30.3° |
c = 10.2031 (5) Å | µ = 0.11 mm−1 |
β = 95.196 (2)° | T = 297 K |
V = 1379.78 (11) Å3 | Block, colourless |
Z = 4 | 0.16 × 0.13 × 0.10 mm |
Bruker APEXII CCD diffractometer | 2302 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.028 |
Absorption correction: multi-scan (TWINABS; Sheldrick, 2012) | θmax = 26.0°, θmin = 2.3° |
h = −8→8 | |
2696 measured reflections | k = 0→24 |
2696 independent reflections | l = 0→12 |
Refinement on F2 | 1 restraint |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.043 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.121 | w = 1/[σ2(Fo2) + (0.0606P)2 + 0.3029P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max < 0.001 |
2696 reflections | Δρmax = 0.18 e Å−3 |
208 parameters | Δρmin = −0.20 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
Refinement. Refined as a 2-component twin. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.3744 (2) | 0.45226 (6) | 0.80648 (13) | 0.0531 (4) | |
H1 | 0.344 (4) | 0.4379 (12) | 0.7235 (19) | 0.080* | |
O2 | 0.6082 (2) | 0.28918 (6) | 1.00744 (12) | 0.0469 (3) | |
O3 | 0.6119 (3) | 0.22490 (6) | 0.83226 (13) | 0.0663 (5) | |
O4 | 0.0188 (3) | 0.67218 (8) | 0.2507 (2) | 0.0812 (6) | |
O5 | −0.0004 (3) | 0.61297 (9) | 0.07175 (19) | 0.0865 (6) | |
N1 | 0.0349 (3) | 0.61838 (9) | 0.1917 (2) | 0.0611 (5) | |
N2 | 0.3120 (2) | 0.38498 (7) | 0.46572 (14) | 0.0398 (4) | |
H2 | 0.268 (3) | 0.3474 (11) | 0.432 (2) | 0.048* | |
N3 | 0.3581 (2) | 0.38475 (6) | 0.60024 (13) | 0.0347 (3) | |
C1 | 0.1015 (3) | 0.55793 (9) | 0.2667 (2) | 0.0451 (5) | |
C2 | 0.1693 (3) | 0.56440 (9) | 0.3967 (2) | 0.0444 (4) | |
H2A | 0.167336 | 0.606928 | 0.437835 | 0.053* | |
C3 | 0.2406 (3) | 0.50781 (8) | 0.46645 (17) | 0.0391 (4) | |
H3 | 0.289862 | 0.512366 | 0.553813 | 0.047* | |
C4 | 0.2383 (2) | 0.44367 (8) | 0.40531 (16) | 0.0337 (4) | |
C5 | 0.1636 (3) | 0.43827 (9) | 0.27327 (18) | 0.0462 (5) | |
H5 | 0.158976 | 0.395663 | 0.232158 | 0.055* | |
C6 | 0.0978 (3) | 0.49483 (10) | 0.20466 (19) | 0.0517 (5) | |
H6 | 0.050752 | 0.491001 | 0.116717 | 0.062* | |
C7 | 0.5379 (3) | 0.27794 (9) | 0.57620 (17) | 0.0454 (5) | |
H7A | 0.454884 | 0.238623 | 0.575635 | 0.068* | |
H7B | 0.664122 | 0.265763 | 0.614883 | 0.068* | |
H7C | 0.546326 | 0.293406 | 0.487576 | 0.068* | |
C8 | 0.4574 (2) | 0.33419 (8) | 0.65505 (16) | 0.0332 (4) | |
C9 | 0.5723 (3) | 0.28148 (8) | 0.87201 (16) | 0.0410 (4) | |
C10 | 0.4942 (2) | 0.33851 (8) | 0.79792 (15) | 0.0329 (4) | |
C11 | 0.4516 (3) | 0.39848 (8) | 0.86652 (17) | 0.0389 (4) | |
C12 | 0.4968 (3) | 0.40211 (10) | 1.00539 (19) | 0.0491 (5) | |
H12 | 0.472308 | 0.442214 | 1.050290 | 0.059* | |
C13 | 0.5736 (3) | 0.34866 (9) | 1.07078 (17) | 0.0451 (4) | |
C14 | 0.6316 (4) | 0.34367 (13) | 1.21487 (19) | 0.0689 (7) | |
H14A | 0.564868 | 0.306098 | 1.251241 | 0.103* | |
H14B | 0.599050 | 0.385539 | 1.257136 | 0.103* | |
H14C | 0.768155 | 0.336166 | 1.228953 | 0.103* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0792 (10) | 0.0393 (7) | 0.0400 (7) | 0.0220 (7) | 0.0012 (7) | 0.0015 (6) |
O2 | 0.0651 (8) | 0.0416 (7) | 0.0322 (6) | 0.0067 (6) | −0.0064 (6) | 0.0044 (5) |
O3 | 0.1158 (14) | 0.0320 (6) | 0.0454 (8) | 0.0182 (8) | −0.0238 (8) | −0.0018 (6) |
O4 | 0.0772 (12) | 0.0448 (9) | 0.1196 (16) | 0.0129 (8) | −0.0011 (11) | 0.0242 (9) |
O5 | 0.0958 (14) | 0.0791 (12) | 0.0806 (13) | 0.0013 (10) | −0.0138 (11) | 0.0484 (10) |
N1 | 0.0438 (9) | 0.0498 (10) | 0.0889 (15) | 0.0011 (8) | 0.0009 (9) | 0.0340 (10) |
N2 | 0.0555 (9) | 0.0297 (7) | 0.0317 (8) | −0.0015 (7) | −0.0101 (6) | 0.0025 (6) |
N3 | 0.0398 (8) | 0.0327 (7) | 0.0303 (7) | −0.0018 (6) | −0.0039 (6) | 0.0047 (5) |
C1 | 0.0382 (9) | 0.0397 (9) | 0.0563 (12) | −0.0006 (8) | −0.0016 (8) | 0.0210 (8) |
C2 | 0.0436 (10) | 0.0312 (8) | 0.0587 (12) | −0.0023 (8) | 0.0059 (9) | 0.0048 (8) |
C3 | 0.0427 (9) | 0.0347 (8) | 0.0389 (10) | −0.0036 (7) | −0.0017 (8) | 0.0025 (7) |
C4 | 0.0349 (8) | 0.0308 (8) | 0.0345 (9) | −0.0030 (6) | −0.0025 (7) | 0.0068 (6) |
C5 | 0.0610 (11) | 0.0383 (9) | 0.0371 (10) | −0.0013 (9) | −0.0068 (9) | 0.0042 (7) |
C6 | 0.0611 (12) | 0.0516 (11) | 0.0396 (10) | −0.0018 (10) | −0.0102 (9) | 0.0134 (8) |
C7 | 0.0601 (12) | 0.0401 (9) | 0.0342 (9) | 0.0088 (9) | −0.0052 (8) | −0.0031 (7) |
C8 | 0.0364 (8) | 0.0277 (7) | 0.0344 (8) | −0.0031 (6) | −0.0026 (7) | 0.0014 (6) |
C9 | 0.0547 (11) | 0.0331 (8) | 0.0329 (9) | 0.0011 (8) | −0.0083 (8) | 0.0020 (7) |
C10 | 0.0368 (8) | 0.0301 (8) | 0.0307 (8) | −0.0006 (6) | −0.0024 (7) | 0.0023 (6) |
C11 | 0.0458 (10) | 0.0337 (8) | 0.0371 (9) | 0.0051 (7) | 0.0028 (7) | 0.0024 (7) |
C12 | 0.0670 (13) | 0.0450 (10) | 0.0354 (9) | 0.0098 (9) | 0.0053 (9) | −0.0048 (8) |
C13 | 0.0550 (11) | 0.0494 (10) | 0.0304 (9) | 0.0041 (9) | 0.0020 (8) | −0.0008 (8) |
C14 | 0.0965 (18) | 0.0774 (15) | 0.0312 (10) | 0.0156 (14) | −0.0026 (11) | −0.0018 (10) |
O1—C11 | 1.305 (2) | C4—C5 | 1.403 (2) |
O1—H1 | 0.899 (17) | C5—C6 | 1.363 (2) |
O2—C13 | 1.360 (2) | C5—H5 | 0.9300 |
O2—C9 | 1.390 (2) | C6—H6 | 0.9300 |
O3—C9 | 1.216 (2) | C7—C8 | 1.499 (2) |
O4—N1 | 1.220 (2) | C7—H7A | 0.9600 |
O5—N1 | 1.231 (3) | C7—H7B | 0.9600 |
N1—C1 | 1.458 (2) | C7—H7C | 0.9600 |
N2—C4 | 1.377 (2) | C8—C10 | 1.460 (2) |
N2—N3 | 1.3809 (18) | C9—C10 | 1.424 (2) |
N2—H2 | 0.85 (2) | C10—C11 | 1.408 (2) |
N3—C8 | 1.301 (2) | C11—C12 | 1.425 (3) |
C1—C2 | 1.373 (3) | C12—C13 | 1.324 (3) |
C1—C6 | 1.383 (3) | C12—H12 | 0.9300 |
C2—C3 | 1.381 (2) | C13—C14 | 1.492 (2) |
C2—H2A | 0.9300 | C14—H14A | 0.9600 |
C3—C4 | 1.397 (2) | C14—H14B | 0.9600 |
C3—H3 | 0.9300 | C14—H14C | 0.9600 |
C11—O1—H1 | 104.1 (16) | H7A—C7—H7B | 109.5 |
C13—O2—C9 | 122.74 (13) | C8—C7—H7C | 109.5 |
O4—N1—O5 | 123.05 (18) | H7A—C7—H7C | 109.5 |
O4—N1—C1 | 118.4 (2) | H7B—C7—H7C | 109.5 |
O5—N1—C1 | 118.5 (2) | N3—C8—C10 | 115.09 (14) |
C4—N2—N3 | 119.41 (13) | N3—C8—C7 | 122.27 (14) |
C4—N2—H2 | 115.4 (14) | C10—C8—C7 | 122.54 (14) |
N3—N2—H2 | 116.0 (14) | O3—C9—O2 | 113.81 (14) |
C8—N3—N2 | 119.75 (14) | O3—C9—C10 | 128.22 (15) |
C2—C1—C6 | 120.96 (16) | O2—C9—C10 | 117.97 (14) |
C2—C1—N1 | 119.85 (18) | C11—C10—C9 | 118.16 (15) |
C6—C1—N1 | 119.18 (18) | C11—C10—C8 | 121.23 (14) |
C1—C2—C3 | 120.03 (16) | C9—C10—C8 | 120.60 (14) |
C1—C2—H2A | 120.0 | O1—C11—C10 | 122.02 (16) |
C3—C2—H2A | 120.0 | O1—C11—C12 | 118.12 (15) |
C2—C3—C4 | 119.77 (16) | C10—C11—C12 | 119.85 (15) |
C2—C3—H3 | 120.1 | C13—C12—C11 | 120.32 (17) |
C4—C3—H3 | 120.1 | C13—C12—H12 | 119.8 |
N2—C4—C3 | 123.76 (14) | C11—C12—H12 | 119.8 |
N2—C4—C5 | 117.25 (15) | C12—C13—O2 | 120.85 (16) |
C3—C4—C5 | 118.95 (15) | C12—C13—C14 | 127.50 (18) |
C6—C5—C4 | 120.68 (17) | O2—C13—C14 | 111.65 (16) |
C6—C5—H5 | 119.7 | C13—C14—H14A | 109.5 |
C4—C5—H5 | 119.7 | C13—C14—H14B | 109.5 |
C5—C6—C1 | 119.57 (17) | H14A—C14—H14B | 109.5 |
C5—C6—H6 | 120.2 | C13—C14—H14C | 109.5 |
C1—C6—H6 | 120.2 | H14A—C14—H14C | 109.5 |
C8—C7—H7A | 109.5 | H14B—C14—H14C | 109.5 |
C8—C7—H7B | 109.5 | ||
C4—N2—N3—C8 | −168.31 (16) | C13—O2—C9—C10 | −0.6 (3) |
O4—N1—C1—C2 | −9.0 (3) | O3—C9—C10—C11 | 177.1 (2) |
O5—N1—C1—C2 | 170.29 (19) | O2—C9—C10—C11 | −2.2 (3) |
O4—N1—C1—C6 | 172.0 (2) | O3—C9—C10—C8 | −2.0 (3) |
O5—N1—C1—C6 | −8.7 (3) | O2—C9—C10—C8 | 178.60 (16) |
C6—C1—C2—C3 | 1.9 (3) | N3—C8—C10—C11 | −9.8 (2) |
N1—C1—C2—C3 | −177.08 (17) | C7—C8—C10—C11 | 166.71 (17) |
C1—C2—C3—C4 | −1.8 (3) | N3—C8—C10—C9 | 169.40 (16) |
N3—N2—C4—C3 | 12.9 (3) | C7—C8—C10—C9 | −14.1 (3) |
N3—N2—C4—C5 | −169.53 (16) | C9—C10—C11—O1 | −177.92 (17) |
C2—C3—C4—N2 | 177.75 (17) | C8—C10—C11—O1 | 1.3 (3) |
C2—C3—C4—C5 | 0.2 (3) | C9—C10—C11—C12 | 3.5 (3) |
N2—C4—C5—C6 | −176.40 (19) | C8—C10—C11—C12 | −177.33 (18) |
C3—C4—C5—C6 | 1.3 (3) | O1—C11—C12—C13 | 179.38 (19) |
C4—C5—C6—C1 | −1.2 (3) | C10—C11—C12—C13 | −2.0 (3) |
C2—C1—C6—C5 | −0.4 (3) | C11—C12—C13—O2 | −0.9 (3) |
N1—C1—C6—C5 | 178.59 (18) | C11—C12—C13—C14 | 179.3 (2) |
N2—N3—C8—C10 | −178.73 (15) | C9—O2—C13—C12 | 2.3 (3) |
N2—N3—C8—C7 | 4.8 (2) | C9—O2—C13—C14 | −177.92 (19) |
C13—O2—C9—O3 | 179.91 (19) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N3 | 0.90 (2) | 1.64 (2) | 2.4760 (18) | 154 (2) |
N2—H2···O3i | 0.85 (2) | 2.00 (2) | 2.8361 (19) | 165.2 (19) |
C5—H5···O3i | 0.93 | 2.60 | 3.264 (2) | 129 |
C7—H7A···O2i | 0.96 | 2.51 | 3.283 (2) | 138 |
Symmetry code: (i) x−1/2, −y+1/2, z−1/2. |
Acknowledgements
The authors thank the School of Chemistry, Hyderabad Central University, Hyderabad 500 046, India, for the single-crystal X-ray data collection. RK thanks the University Grant Commission (UGC), New Delhi, India, for providing financial support in the form of a UGC–BSR research start-up grant [F. 30–86/2014(BSR)].
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