research communications
E)-N′-(3-hydroxy-4-methoxybenzylidene)nicotinohydrazide monohydrate
Hirshfeld surface analysis and HOMO–LUMO analysis of (aDepartment of Chemistry, Government Arts College (Autonomous), Thanthonimalai, Karur 639 005, Tamil Nadu, India, and bDepartment of Chemistry, Pondicherry University, R.V. Nagar, Kalapet, Puducherry 605 014, India
*Correspondence e-mail: manavaibala@gmail.com
The molecule of the title Schiff base compound, C14H13N3O3·H2O, displays a trans configuration with respect to the C=N bond. The dihedral angle between the benzene and pyridine rings is 29.63 (7)°. The features intermolecular N—H⋯O, C—H⋯O, O—H⋯O and O—H⋯N hydrogen-bonding interactions, leading to the formation of a supramolecular framework. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (37.0%), O⋯H/H⋯O (23.7%)), C⋯H/H⋯C (17.6%) and N⋯H/H⋯N (11.9%) interactions. The title compound has also been characterized by frontier molecular orbital analysis.
Keywords: crystal structure; Schiff base; intermolecular interactions; Hirshfeld surface analysis.
CCDC reference: 1587259
1. Chemical context
). A wide range of these compounds, with the general formula RHC=NR1 (R and R1 can be alkyl, aryl, cycloalkyl or heterocyclic groups) have been synthesized. are of great importance in the field of coordination chemistry because they are able to form stable complexes with metal ions (Souza et al., 1985). The chemical and biological significance of can be attributed to the presence of a in the sp2-hybridized orbital of the nitrogen atom of the azomethine group (Singh et al., 1975). These compounds are used in the fields of organic synthesis, chemical catalysis, medicine and pharmacy, as well as other new technologies (Tanaka et al., 2010). are also used as probes for investigating the structure of DNA (Tiwari et al., 2011) and have gained special attention in pharmacophore research and in the development of several bioactive lead molecules (Muralisankar et al., 2016). showing photochromic and thermochromic properties have been used in information storage, electronic display systems, optical switching devices and ophthalmic glasses (Amimoto et al., 2005). As a further contribution to this field of research, we report herein the of the title compound, (E)-N′-(3-hydroxy-4-methoxybenzylidene)nicotinohydrazide monohydrate.
are nitrogen-containing compounds that were first obtained by the condensation reaction of aromatic and (Schiff, 18642. Structural commentary
The ) consists of one independent Schiff base molecule displaying a trans configuration with respect to the C=N bond and a water molecule. All the bond lengths are within the normal ranges (Allen et al., 1987). The C7=N3 bond length of 1.274 (2) Å is consistent with a double-bond character. The C6—N2 and N2—N3 bond lengths of 1.343 (2) and 1.3866 (16) Å, respectively, are comparable to those observed in related compounds (Sivajeyanthi et al., 2017; Balasubramani et al., 2018). The O1/C6/N2/N3/C7 core is almost planar (r.m.s. deviation = 0.022 Å) and forms dihedral angles of 20.75 (7) and 8.93 (5)°, respectively, with the pyridine and benzene rings.
of the title compound (Fig. 13. Supramolecular features
In the crystal of the title compound (Fig. 2), the water molecule interacts with three neighbouring nicotinohydrazide molecules with the O4 water oxygen atom acting as a hydrogen acceptor through N2—H2N⋯O4 and C2—H2⋯O4 hydrogen bonds (Table 1), and both water H atoms acting as bifurcated donors to form rings of R21(5) graph-set motif. The nicotinohydrazide molecules are further linked by O—H⋯N and C—H⋯O hydrogen bonds to form a three-dimensional network.
4. Hirshfeld surface analysis
The three-dimensional dnorm surface is a useful tool for analysing and visualizing the intermolecular interactions, as it shows negative or positive values depending on whether an intermolecular contact is shorter or longer, respectively, than the sum of the van der Waals radii (Spackman & Jayatilaka, 2009; McKinnon et al., 2007). The dnorm surface of the title compound is shown in Fig. 3. The red points, which represent closer contacts and negative dnorm values, correspond to the N—H⋯O, O—H⋯O, O—H⋯N and C—H⋯O interactions. Two-dimensional fingerprint plots from the Hirshfeld surface analysis (Fig. 4) provide information about the intermolecular contacts and their percentage distributions on the Hirshfeld surface. The percentage of H⋯H contacts as closest contacts on the Hirshfeld surfaces is a universally applicable measure of the energy and can be used as a reference for the importance of other types of contacts. In the title compound, the percentage contributions of the various intermolecular contacts to the total Hirshfeld surface are as follows: H⋯H (37.0%), C⋯H/H⋯C (17.6%), N⋯H/H⋯N (11.9%), C⋯N/N⋯C (3.7%), O⋯H/H⋯O (23.7%), C⋯C (4.5%), N⋯N (0.3%) and O⋯C/C⋯O (1.2%).
5. Frontier molecular orbitals
The HOMO (highest occupied molecular orbital) acts as an et al., 2017). The energy levels, energy gaps, chemical hardness, and index are given in Table 2. As shown in Fig. 5, the frontier molecular orbital LUMO is located over the whole of the molecule. The energy gap of the molecule clearly shows the charge-transfer interaction involving donor and acceptor groups. If the HOMO–LUMO energy gap is small, then the molecule is defined as soft, i.e. it is highly polarizable and has high chemical reactivity, whereas if the energy gap is large the molecule can be defined as hard. Therefore from Table 2 we conclude that the title molecule belongs to the really hard materials.
and LUMO (lowest occupied molecular orbital) acts as an If the HOMO–LUMO energy gap is small, then the molecule is highly polarizable and has high chemical reactivity. The energy levels for the title compound were computed by DFT-B3LYP/6-311G++(d,p) method (Sivajeyanthi
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6. Database survey
A search of the Cambridge Structural Database (Version 5.40, update November 2018; Groom et al., 2016) for uncoordinated N′-(benzylidene)nicotinohydrazide derivatives O-substituted at the 3,4 positions of the benzene ring yielded three hits, namely N′-(1,3-benzodioxol-5-ylmethylene)nicotinohydrazide monohydrate (refcode BUDNIY; Bao et al., 2009), N′-(3,4-dimethoxybenzylidene)nicotinohydrazide monohydrate (XODZOH; Novina et al., 2014) and the isomer N′-(4-hydroxy-3-methoxybenzylidene)nicotinohydrazide monohydrate (SEZREV; Shi et al., 2007). The conformation of the last molecule differs from the title compound mainly in the relative orientation of the pyridine ring with respect to the carbonyl group, as indicated by the value of 158.03 (15)° for the O1—C6—C1—C2 torsion angle in the title compound and of 10.2 (3)° for the corresponding angle in SEZREV. Moreover, in SEZREV the water molecule acts as acceptor of three H atoms from the same nicotinohydrazide molecule and as donor in two O—H⋯O hydrogen bonds.
7. Synthesis and crystallization
The title compound was synthesized by the reaction of a 1:1 molar ratio mixture of a hot ethanolic solution (20 ml) of nicotinohydrazide (0.137 mg) and a hot ethanolic solution of 3-hydroxy-4-methoxy benzaldehyde (0.152 mg). After refluxing for 8 h, the solution was then cooled and kept at room temperature to precipitate. Colourless block-shaped crystals suitable for X-ray analysis were obtained by slow evaporation of a 10 ml dimethyl sulfoxide/water (1:1 v/v) solution.
8. Refinement
Crystal data, data collection and structure . H atoms were positioned geometrically (O—H = 0.82 Å, N–H = 0.86 Å, C—H = 0.93–0.96 Å) and refined as riding with Uiso(H) = 1.2Ueq(C,N) or 1.5Ueq(O, C-methyl)
details are summarized in Table 3
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Supporting information
CCDC reference: 1587259
https://doi.org/10.1107/S2056989019006492/rz5252sup1.cif
contains datablocks global, I, 1. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989019006492/rz5252Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989019006492/rz5252Isup3.cml
Data collection: CrysAlis PRO (Agilent, 2012); cell
CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2017 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL2017 (Sheldrick, 2015).C14H13N3O3·H2O | F(000) = 608 |
Mr = 289.29 | Dx = 1.395 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 7.1153 (4) Å | Cell parameters from 3729 reflections |
b = 11.0075 (6) Å | θ = 3.9–29.2° |
c = 18.2771 (10) Å | µ = 0.10 mm−1 |
β = 105.766 (5)° | T = 295 K |
V = 1377.64 (14) Å3 | Block, colourless |
Z = 4 | 0.30 × 0.25 × 0.18 mm |
Agilent Xcalibur Eos diffractometer | 2549 independent reflections |
Radiation source: fine-focus sealed tube | 2027 reflections with I > 2σ(I) |
Detector resolution: 15.9821 pixels mm-1 | Rint = 0.027 |
ω scans | θmax = 25.5°, θmin = 3.9° |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012) | h = −8→8 |
Tmin = 0.969, Tmax = 0.981 | k = −13→12 |
8396 measured reflections | l = −22→22 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.036 | H-atom parameters constrained |
wR(F2) = 0.101 | w = 1/[σ2(Fo2) + (0.0462P)2 + 0.2987P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max < 0.001 |
2549 reflections | Δρmax = 0.16 e Å−3 |
192 parameters | Δρmin = −0.13 e Å−3 |
0 restraints | Extinction correction: SHELXL2017 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.030 (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. 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 > 2sigma(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. |
x | y | z | Uiso*/Ueq | ||
O3 | −0.03769 (14) | 0.40424 (10) | 0.06695 (6) | 0.0455 (3) | |
O2 | 0.20750 (15) | 0.23383 (10) | 0.06507 (7) | 0.0537 (3) | |
H10 | 0.287088 | 0.178188 | 0.073527 | 0.081* | |
O1 | 1.15498 (17) | 0.21431 (11) | 0.30304 (8) | 0.0604 (4) | |
N3 | 0.85559 (17) | 0.37007 (12) | 0.26300 (7) | 0.0418 (3) | |
N2 | 1.03456 (17) | 0.40123 (12) | 0.31206 (7) | 0.0410 (3) | |
H2N | 1.053128 | 0.472235 | 0.332397 | 0.049* | |
N1 | 1.61018 (19) | 0.51282 (12) | 0.42610 (8) | 0.0452 (4) | |
C8 | 0.5291 (2) | 0.43898 (15) | 0.20366 (8) | 0.0371 (4) | |
C9 | 0.4682 (2) | 0.33704 (14) | 0.15750 (8) | 0.0384 (4) | |
H9 | 0.555924 | 0.274429 | 0.157443 | 0.046* | |
C10 | 0.2791 (2) | 0.32888 (14) | 0.11216 (8) | 0.0372 (4) | |
C11 | 0.1465 (2) | 0.42290 (14) | 0.11294 (8) | 0.0355 (4) | |
C12 | 0.2059 (2) | 0.52410 (15) | 0.15746 (9) | 0.0409 (4) | |
H12 | 0.118419 | 0.586791 | 0.157676 | 0.049* | |
C13 | 0.3972 (2) | 0.53171 (15) | 0.20196 (9) | 0.0423 (4) | |
H13 | 0.437730 | 0.600772 | 0.231319 | 0.051* | |
C14 | −0.1795 (2) | 0.49637 (17) | 0.06553 (10) | 0.0492 (4) | |
H14A | −0.192906 | 0.508196 | 0.115902 | 0.074* | |
H14B | −0.302791 | 0.472017 | 0.032256 | 0.074* | |
H14C | −0.138193 | 0.570937 | 0.047468 | 0.074* | |
C7 | 0.7260 (2) | 0.45278 (15) | 0.25379 (8) | 0.0411 (4) | |
H7 | 0.758441 | 0.525352 | 0.280265 | 0.049* | |
C6 | 1.1785 (2) | 0.31829 (14) | 0.32729 (9) | 0.0390 (4) | |
C2 | 1.4323 (2) | 0.47808 (14) | 0.38578 (8) | 0.0387 (4) | |
H2 | 1.343594 | 0.537888 | 0.362746 | 0.046* | |
C1 | 1.3728 (2) | 0.35815 (13) | 0.37638 (8) | 0.0354 (4) | |
C5 | 1.5059 (2) | 0.27035 (15) | 0.41019 (10) | 0.0502 (4) | |
H5 | 1.472088 | 0.188603 | 0.404400 | 0.060* | |
C4 | 1.6891 (2) | 0.30435 (17) | 0.45260 (11) | 0.0599 (5) | |
H4 | 1.780614 | 0.246398 | 0.476287 | 0.072* | |
C3 | 1.7334 (2) | 0.42511 (17) | 0.45907 (10) | 0.0533 (5) | |
H3 | 1.857046 | 0.447633 | 0.488254 | 0.064* | |
O4 | 1.07802 (17) | 0.65762 (11) | 0.34578 (7) | 0.0594 (4) | |
H4WA | 1.034030 | 0.696974 | 0.377588 | 0.089* | |
H4WB | 1.043530 | 0.692674 | 0.302788 | 0.089* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O3 | 0.0286 (5) | 0.0448 (7) | 0.0558 (7) | 0.0044 (5) | −0.0009 (5) | −0.0023 (5) |
O2 | 0.0385 (6) | 0.0378 (6) | 0.0712 (8) | 0.0062 (5) | −0.0085 (5) | −0.0115 (6) |
O1 | 0.0513 (7) | 0.0382 (7) | 0.0744 (9) | −0.0022 (5) | −0.0127 (6) | −0.0079 (6) |
N3 | 0.0309 (6) | 0.0455 (8) | 0.0416 (7) | −0.0061 (6) | −0.0029 (5) | 0.0026 (6) |
N2 | 0.0311 (6) | 0.0390 (7) | 0.0448 (7) | −0.0032 (6) | −0.0037 (5) | −0.0026 (6) |
N1 | 0.0361 (7) | 0.0419 (8) | 0.0509 (8) | −0.0062 (6) | 0.0006 (6) | 0.0030 (6) |
C8 | 0.0317 (7) | 0.0424 (9) | 0.0351 (8) | −0.0033 (7) | 0.0054 (6) | 0.0051 (7) |
C9 | 0.0306 (7) | 0.0373 (8) | 0.0437 (8) | 0.0036 (6) | 0.0039 (6) | 0.0062 (7) |
C10 | 0.0343 (8) | 0.0327 (8) | 0.0408 (8) | −0.0019 (6) | 0.0038 (6) | 0.0024 (7) |
C11 | 0.0281 (7) | 0.0388 (9) | 0.0369 (8) | −0.0003 (6) | 0.0039 (6) | 0.0052 (7) |
C12 | 0.0369 (8) | 0.0403 (9) | 0.0435 (8) | 0.0051 (7) | 0.0073 (6) | −0.0004 (7) |
C13 | 0.0399 (8) | 0.0422 (9) | 0.0412 (8) | −0.0020 (7) | 0.0049 (7) | −0.0052 (7) |
C14 | 0.0325 (8) | 0.0598 (11) | 0.0520 (10) | 0.0118 (8) | 0.0056 (7) | 0.0013 (8) |
C7 | 0.0348 (8) | 0.0446 (9) | 0.0397 (8) | −0.0055 (7) | 0.0030 (6) | 0.0012 (7) |
C6 | 0.0370 (8) | 0.0345 (9) | 0.0398 (8) | −0.0047 (7) | 0.0007 (6) | 0.0025 (7) |
C2 | 0.0320 (8) | 0.0364 (8) | 0.0432 (8) | −0.0003 (6) | 0.0023 (6) | 0.0041 (7) |
C1 | 0.0321 (7) | 0.0359 (8) | 0.0345 (7) | −0.0008 (6) | 0.0026 (6) | 0.0024 (6) |
C5 | 0.0457 (9) | 0.0361 (9) | 0.0580 (10) | −0.0003 (7) | −0.0041 (8) | 0.0050 (8) |
C4 | 0.0432 (10) | 0.0477 (11) | 0.0728 (13) | 0.0060 (8) | −0.0114 (9) | 0.0120 (9) |
C3 | 0.0328 (8) | 0.0540 (11) | 0.0611 (11) | −0.0043 (8) | −0.0075 (7) | 0.0063 (9) |
O4 | 0.0627 (8) | 0.0475 (7) | 0.0583 (7) | 0.0186 (6) | −0.0002 (6) | −0.0017 (6) |
O3—C11 | 1.3664 (17) | C12—C13 | 1.386 (2) |
O3—C14 | 1.4257 (19) | C12—H12 | 0.9300 |
O2—C10 | 1.3627 (18) | C13—H13 | 0.9300 |
O2—H10 | 0.8198 | C14—H14A | 0.9600 |
O1—C6 | 1.2223 (19) | C14—H14B | 0.9600 |
N3—C7 | 1.274 (2) | C14—H14C | 0.9600 |
N3—N2 | 1.3866 (16) | C7—H7 | 0.9300 |
N2—C6 | 1.343 (2) | C6—C1 | 1.4950 (19) |
N2—H2N | 0.8602 | C2—C1 | 1.383 (2) |
N1—C3 | 1.333 (2) | C2—H2 | 0.9300 |
N1—C2 | 1.3355 (19) | C1—C5 | 1.376 (2) |
C8—C13 | 1.381 (2) | C5—C4 | 1.376 (2) |
C8—C9 | 1.400 (2) | C5—H5 | 0.9300 |
C8—C7 | 1.459 (2) | C4—C3 | 1.364 (3) |
C9—C10 | 1.378 (2) | C4—H4 | 0.9300 |
C9—H9 | 0.9300 | C3—H3 | 0.9300 |
C10—C11 | 1.404 (2) | O4—H4WA | 0.8500 |
C11—C12 | 1.377 (2) | O4—H4WB | 0.8495 |
C11—O3—C14 | 117.37 (12) | H14A—C14—H14B | 109.5 |
C10—O2—H10 | 109.5 | O3—C14—H14C | 109.5 |
C7—N3—N2 | 114.41 (13) | H14A—C14—H14C | 109.5 |
C6—N2—N3 | 118.71 (13) | H14B—C14—H14C | 109.5 |
C6—N2—H2N | 120.6 | N3—C7—C8 | 123.07 (15) |
N3—N2—H2N | 120.7 | N3—C7—H7 | 118.5 |
C3—N1—C2 | 116.76 (14) | C8—C7—H7 | 118.5 |
C13—C8—C9 | 118.80 (13) | O1—C6—N2 | 122.66 (13) |
C13—C8—C7 | 117.90 (14) | O1—C6—C1 | 120.37 (14) |
C9—C8—C7 | 123.31 (14) | N2—C6—C1 | 116.97 (13) |
C10—C9—C8 | 120.43 (14) | N1—C2—C1 | 123.65 (14) |
C10—C9—H9 | 119.8 | N1—C2—H2 | 118.2 |
C8—C9—H9 | 119.8 | C1—C2—H2 | 118.2 |
O2—C10—C9 | 124.50 (13) | C5—C1—C2 | 117.67 (13) |
O2—C10—C11 | 115.81 (12) | C5—C1—C6 | 118.33 (14) |
C9—C10—C11 | 119.69 (14) | C2—C1—C6 | 123.84 (13) |
O3—C11—C12 | 125.07 (13) | C4—C5—C1 | 119.55 (15) |
O3—C11—C10 | 114.71 (13) | C4—C5—H5 | 120.2 |
C12—C11—C10 | 120.22 (13) | C1—C5—H5 | 120.2 |
C11—C12—C13 | 119.40 (14) | C3—C4—C5 | 118.38 (15) |
C11—C12—H12 | 120.3 | C3—C4—H4 | 120.8 |
C13—C12—H12 | 120.3 | C5—C4—H4 | 120.8 |
C8—C13—C12 | 121.44 (15) | N1—C3—C4 | 123.96 (15) |
C8—C13—H13 | 119.3 | N1—C3—H3 | 118.0 |
C12—C13—H13 | 119.3 | C4—C3—H3 | 118.0 |
O3—C14—H14A | 109.5 | H4WA—O4—H4WB | 109.5 |
O3—C14—H14B | 109.5 |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H4WA···O2i | 0.85 | 2.28 | 3.0483 (17) | 150 |
O4—H4WA···O3i | 0.85 | 2.49 | 3.2011 (16) | 141 |
O4—H4WB···O1ii | 0.85 | 2.08 | 2.8429 (19) | 150 |
O4—H4WB···N3ii | 0.85 | 2.50 | 3.1875 (18) | 139 |
N2—H2N···O4 | 0.86 | 2.06 | 2.8889 (18) | 162 |
O2—H10···N1iii | 0.82 | 1.96 | 2.7411 (17) | 159 |
C2—H2···O4 | 0.93 | 2.25 | 3.129 (2) | 156 |
C4—H4···O3iv | 0.93 | 2.45 | 3.347 (2) | 163 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+2, y+1/2, −z+1/2; (iii) −x+2, y−1/2, −z+1/2; (iv) x+2, −y+1/2, z+1/2. |
FMO | Energy |
EHOMO | -5.7171 |
ELUMO | -1.8174 |
EHOMO-1 | -6.5750 |
ELUMO+1 | -1.2770 |
(EHOMO - ELUMO) gap | 3.8997 |
(EHOMO-1 - ELUMO+1) gap | 5.2980 |
Chemical hardness | 1.9498 |
Chemical potential | 3.7672 |
Electronegativity | -3.7672 |
Electrophilicity index | 3.6393 |
Funding information
KB and PS thank the Department of Science and Technology (DST–SERB), New Delhi, India, grant No. SB/FT/CS-058/2013, for financial support.
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