research communications
Z)-2-[(E)-2-benzylidenehydrazin-1-ylidene]-1,2-diphenylethanone
of (aLaboratoire de Chimie, Ingénierie Moléculaire et Nanostructures (LCIMN), Université Ferhat Abbas Sétif 1, Sétif 19000, Algeria, bLaboratoire d'Electrochimie des Matériaux Moléculaires et Complexes (L.E.M.M.C.), Université Ferhat Abbas Sétif 1, Sétif 19000, Algeria, cDépartement de Technologie, Faculté de Technologie, Université 20 Août 1955-Skikda, BP 26, Route d'El-Hadaiek, Skikda 21000, Algeria, and dDepartment of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
*Correspondence e-mail: setifi_zouaoui@yahoo.fr
The title compound, C21H16N2O, has an almost planar (r.m.s. deviation = 0.0074 Å) 1,2-dibenzylidenehydrazine backbone with an approximately orthogonal almost planar (r.m.s. deviation = 0.0368 Å) phenylethanone substituent on one of the imine C atoms. The dihedral angle between the two mean planes is 76.99 (4)°. In the crystal, molecules are linked via C—H⋯O hydrogen bonds and C—H⋯π contacts, forming a three-dimensional structure with molecules stacked along the a-axis direction.
Keywords: crystal structure; Schiff base; azines; dimers; C—H⋯π contacts.
CCDC reference: 1036846
1. Chemical context
Aromatic et al., 2010) and non-linear fluorophores (Facchetti et al., 2002). They are also noted for their biological and pharmaceutical applications (Wadher et al., 2009; Pandeya et al., 1999). Furthermore, there are many reports of polyazines as highly conjugated polymers functioning in electronic, optoelectronic and photonic applications (Dudis et al., 1993). As part of our studies of Schiff base the title compound was synthesized and its molecular and are reported on herein.
react easily with to form which can condense with a second molecule of a carbonyl compound to yield an azine. As a result of their fascinating physical and chemical properties, and their derivatives have been utilized extensively in areas such as dyes (Kim2. Structural commentary
The molecule of the title compound, Fig. 1, comprises a 1,2-dibenzylidenehydrazine backbone with a phenyl ethanone substituent on atom C2. Both the hydrazine and ethanone fragments are approximately planar with r.m.s. deviations of 0.0074 Å from the O1/C1/C11–C16 mean plane and 0.0368 Å from the plane through the 16 atoms of the dibenzylidenehydrazine unit. The two mean planes are almost orthogonal with a dihedral angle of 76.99 (4)°. The molecule adopts a Z conformation with respect to the C2=N1 bond and an E conformation with respect to the C3=N2 bond, with the carbonyl atom O1 and the C11–C16 phenyl ring located on opposite sides of the dibenzylidenehydrazine plane. The bond lengths and angles in the title molecule agree reasonably well with those found in closely related structures (Abbasi et al., 2007; Wieland et al., 2011).
3. Supramolecular features
In the crystal, a pair of C35—H35⋯O1 hydrogen bonds link adjacent molecules into dimers with R22(20) ring motifs (Fig. 2 and Table 1). Atom O1 is also involved in two further C—H⋯O hydrogen bonds, C3—H3⋯O1 and C32—H32⋯O1 that generate R21(6) ring motifs. These contacts link the dimers into stacks parallel to (011); see Table 1 and Fig. 2. Interestingly, neither of the hydrazine N atoms are involved in significantly close intermolecular contacts with the shortest intermolecular H12⋯N1 contact being ca 2.85 Å. A contribution to the packing is, however, made by a C—H⋯π interaction (Table 1). These interactions link molecules in a head-to-tail fashion, forming chains along c, as shown in Fig. 3. With 16 molecules in the orthorhombic these various contacts combine to form a three dimensional structure with molecules stacked along the a-axis direction, as shown in Fig. 4.
4. Database survey
A search for the (benzylidenehydrazono)-1,2-diphenylethanone skeleton in the Cambridge Structural Database (Version 5.35, November 2013 with three updates; Groom & Allen, 2014) revealed only 7 similar compounds. The closest to the title structure are 2-{(Z)-2-[(E)-1-(2-hydroxyphenyl)methylidene]hydrazono}-1,2-diphenylethan-1-one (Abbasi et al., 2007), with an hydroxy substituent in the p position on the equivalent of the benzene ring, and 1,2-diphenyl-2-[4-(4-pyridyl)benzylidenehydrazono]ethan-1-one, with a pyridyl ring in the same position (Patra & Ng, 2009). Two reports of polymorphs of the symmetrical 2,2′-(1,2-hydrazinediylidene)-bis(diphenylethanone) have also appeared (Patra et al., 2009; Wieland et al., 2011)
5. Synthesis and crystallization
A mixture of benzaldehyde (0.01 mol, 1.06 g), benzil (0.01 mol, 2.10 g) and hydrazine hydrate (0.01 mol, 0.32 g) in 50 ml of ethanol containing 2 drops of acetic acid was refluxed for about 2 h. The reaction was monitored by TLC until completion. Excess solvent was evaporated under vacuum and the resulting yellow solid product was recrystallized from absolute ethanol to afford yellow needles of the title compound (m.p. 453 K, 75% yield). Analysis calculated for C21H16N2O (312.36): C 80.75, H 5.16, N 8.97%; found: C 80.73, H 5.17, N 9.01%.
6. Refinement
Crystal data, data collection and structure . The C-bound H atoms were included in calculated positions and treated as riding atoms: C—H = 0.95 Å with Uiso = 1.2Ueq(C).
details are summarized in Table 2Supporting information
CCDC reference: 1036846
https://doi.org/10.1107/S2056989014026358/su5029sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989014026358/su5029Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989014026358/su5029Isup3.cml
Data collection: APEX2 (Bruker, 2006); cell
SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: CRYSCAL (T. Roisnel, local program), SHELXL2014 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009), publCIF (Westrip 2010) and WinGX (Farrugia, 2012).C21H16N2O | F(000) = 2624 |
Mr = 312.36 | Dx = 1.240 Mg m−3 |
Orthorhombic, F2dd | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: F -2d 2 | Cell parameters from 2807 reflections |
a = 8.1653 (3) Å | θ = 2.7–27.3° |
b = 27.6113 (11) Å | µ = 0.08 mm−1 |
c = 29.6818 (13) Å | T = 150 K |
V = 6691.9 (5) Å3 | Prism, yellow |
Z = 16 | 0.55 × 0.29 × 0.24 mm |
Bruker APEXII diffractometer | 3036 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.032 |
CCD rotation images, thin slices scans | θmax = 27.5°, θmin = 3.0° |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | h = −9→10 |
Tmin = 0.884, Tmax = 0.982 | k = −35→24 |
8049 measured reflections | l = −38→38 |
3350 independent reflections |
Refinement on F2 | 1 restraint |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.039 | H-atom parameters constrained |
wR(F2) = 0.094 | w = 1/[σ2(Fo2) + (0.0407P)2 + 4.1058P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max < 0.001 |
3350 reflections | Δρmax = 0.18 e Å−3 |
217 parameters | Δρmin = −0.16 e Å−3 |
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. |
x | y | z | Uiso*/Ueq | ||
C11 | 0.4692 (3) | 0.24563 (8) | 0.36467 (7) | 0.0255 (5) | |
C12 | 0.4156 (3) | 0.28709 (9) | 0.34210 (7) | 0.0316 (5) | |
H12 | 0.4758 | 0.3164 | 0.3444 | 0.038* | |
C13 | 0.2746 (3) | 0.28525 (11) | 0.31643 (9) | 0.0426 (7) | |
H13 | 0.2381 | 0.3134 | 0.3010 | 0.051* | |
C14 | 0.1865 (3) | 0.24267 (12) | 0.31313 (10) | 0.0504 (8) | |
H14 | 0.0888 | 0.2418 | 0.2958 | 0.060* | |
C15 | 0.2393 (4) | 0.20147 (11) | 0.33483 (10) | 0.0453 (7) | |
H15 | 0.1790 | 0.1722 | 0.3322 | 0.054* | |
C16 | 0.3810 (3) | 0.20282 (9) | 0.36059 (8) | 0.0326 (6) | |
H16 | 0.4178 | 0.1744 | 0.3755 | 0.039* | |
C1 | 0.6212 (3) | 0.24786 (8) | 0.39198 (6) | 0.0222 (4) | |
O1 | 0.7037 (2) | 0.28433 (5) | 0.39542 (5) | 0.0300 (4) | |
C2 | 0.6774 (3) | 0.20274 (8) | 0.41744 (7) | 0.0220 (5) | |
C21 | 0.6542 (3) | 0.20065 (8) | 0.46670 (6) | 0.0234 (5) | |
C22 | 0.5622 (3) | 0.23566 (9) | 0.48904 (7) | 0.0291 (5) | |
H22 | 0.5110 | 0.2608 | 0.4723 | 0.035* | |
C23 | 0.5449 (3) | 0.23409 (10) | 0.53561 (8) | 0.0344 (6) | |
H23 | 0.4825 | 0.2582 | 0.5507 | 0.041* | |
C24 | 0.6182 (3) | 0.19755 (11) | 0.55991 (8) | 0.0401 (6) | |
H24 | 0.6067 | 0.1966 | 0.5917 | 0.048* | |
C25 | 0.7083 (4) | 0.16228 (11) | 0.53816 (8) | 0.0406 (7) | |
H25 | 0.7575 | 0.1369 | 0.5550 | 0.049* | |
C26 | 0.7272 (3) | 0.16376 (9) | 0.49169 (8) | 0.0332 (6) | |
H26 | 0.7901 | 0.1396 | 0.4769 | 0.040* | |
N1 | 0.7555 (2) | 0.16872 (7) | 0.39690 (6) | 0.0265 (4) | |
N2 | 0.7675 (2) | 0.17867 (7) | 0.35026 (6) | 0.0255 (4) | |
C3 | 0.8450 (3) | 0.14520 (8) | 0.32965 (7) | 0.0245 (5) | |
H3 | 0.8903 | 0.1192 | 0.3465 | 0.029* | |
C31 | 0.8657 (3) | 0.14596 (8) | 0.28078 (7) | 0.0252 (5) | |
C32 | 0.9510 (3) | 0.10863 (9) | 0.25997 (8) | 0.0307 (5) | |
H32 | 0.9991 | 0.0838 | 0.2777 | 0.037* | |
C33 | 0.9664 (3) | 0.10743 (10) | 0.21338 (8) | 0.0383 (6) | |
H33 | 1.0228 | 0.0814 | 0.1993 | 0.046* | |
C34 | 0.9002 (3) | 0.14389 (9) | 0.18749 (8) | 0.0371 (6) | |
H34 | 0.9115 | 0.1431 | 0.1556 | 0.045* | |
C35 | 0.8166 (3) | 0.18203 (10) | 0.20799 (8) | 0.0346 (6) | |
H35 | 0.7721 | 0.2074 | 0.1902 | 0.041* | |
C36 | 0.7987 (3) | 0.18291 (9) | 0.25427 (8) | 0.0294 (5) | |
H36 | 0.7406 | 0.2087 | 0.2682 | 0.035* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C11 | 0.0250 (11) | 0.0314 (12) | 0.0200 (9) | 0.0026 (11) | 0.0015 (8) | 0.0014 (8) |
C12 | 0.0328 (13) | 0.0337 (13) | 0.0283 (11) | 0.0066 (11) | −0.0003 (10) | 0.0044 (10) |
C13 | 0.0368 (15) | 0.0525 (17) | 0.0385 (14) | 0.0136 (14) | −0.0061 (11) | 0.0126 (12) |
C14 | 0.0283 (15) | 0.076 (2) | 0.0472 (15) | −0.0018 (15) | −0.0157 (12) | 0.0105 (15) |
C15 | 0.0348 (15) | 0.0542 (17) | 0.0471 (15) | −0.0116 (14) | −0.0096 (12) | 0.0049 (13) |
C16 | 0.0298 (13) | 0.0375 (14) | 0.0304 (11) | −0.0016 (12) | −0.0019 (9) | 0.0049 (10) |
C1 | 0.0268 (11) | 0.0233 (11) | 0.0166 (8) | 0.0035 (10) | 0.0021 (8) | −0.0012 (8) |
O1 | 0.0370 (10) | 0.0233 (8) | 0.0298 (8) | −0.0021 (8) | −0.0063 (7) | 0.0013 (6) |
C2 | 0.0214 (11) | 0.0228 (10) | 0.0217 (9) | −0.0008 (10) | −0.0023 (8) | 0.0004 (8) |
C21 | 0.0236 (12) | 0.0262 (11) | 0.0205 (9) | −0.0027 (9) | −0.0012 (8) | 0.0029 (8) |
C22 | 0.0292 (13) | 0.0311 (13) | 0.0268 (11) | 0.0028 (11) | 0.0008 (9) | 0.0009 (9) |
C23 | 0.0317 (14) | 0.0428 (15) | 0.0288 (12) | 0.0041 (12) | 0.0054 (10) | −0.0010 (10) |
C24 | 0.0344 (14) | 0.0655 (18) | 0.0203 (10) | 0.0006 (14) | 0.0028 (10) | 0.0063 (12) |
C25 | 0.0372 (15) | 0.0549 (17) | 0.0297 (12) | 0.0075 (14) | −0.0009 (10) | 0.0153 (11) |
C26 | 0.0347 (14) | 0.0367 (14) | 0.0284 (12) | 0.0061 (12) | 0.0004 (10) | 0.0079 (10) |
N1 | 0.0320 (11) | 0.0263 (10) | 0.0212 (9) | 0.0019 (9) | −0.0025 (8) | 0.0019 (7) |
N2 | 0.0317 (11) | 0.0248 (10) | 0.0201 (9) | 0.0012 (9) | −0.0014 (8) | −0.0013 (7) |
C3 | 0.0258 (12) | 0.0213 (11) | 0.0265 (10) | −0.0013 (10) | −0.0021 (8) | 0.0005 (9) |
C31 | 0.0237 (12) | 0.0250 (11) | 0.0268 (10) | −0.0049 (10) | −0.0009 (9) | −0.0034 (9) |
C32 | 0.0327 (14) | 0.0296 (12) | 0.0299 (12) | 0.0014 (11) | 0.0035 (9) | −0.0009 (9) |
C33 | 0.0395 (16) | 0.0419 (15) | 0.0335 (13) | −0.0008 (13) | 0.0100 (10) | −0.0070 (11) |
C34 | 0.0386 (15) | 0.0490 (16) | 0.0238 (10) | −0.0104 (13) | 0.0031 (10) | −0.0019 (10) |
C35 | 0.0359 (14) | 0.0378 (14) | 0.0299 (12) | −0.0038 (12) | −0.0064 (10) | 0.0054 (10) |
C36 | 0.0319 (13) | 0.0256 (12) | 0.0307 (11) | −0.0002 (11) | −0.0049 (10) | 0.0005 (9) |
C11—C16 | 1.390 (3) | C23—H23 | 0.9500 |
C11—C12 | 1.397 (3) | C24—C25 | 1.381 (4) |
C11—C1 | 1.483 (3) | C24—H24 | 0.9500 |
C12—C13 | 1.382 (4) | C25—C26 | 1.388 (3) |
C12—H12 | 0.9500 | C25—H25 | 0.9500 |
C13—C14 | 1.382 (4) | C26—H26 | 0.9500 |
C13—H13 | 0.9500 | N1—N2 | 1.415 (2) |
C14—C15 | 1.377 (4) | N2—C3 | 1.276 (3) |
C14—H14 | 0.9500 | C3—C31 | 1.461 (3) |
C15—C16 | 1.387 (4) | C3—H3 | 0.9500 |
C15—H15 | 0.9500 | C31—C32 | 1.389 (3) |
C16—H16 | 0.9500 | C31—C36 | 1.400 (3) |
C1—O1 | 1.216 (3) | C32—C33 | 1.389 (3) |
C1—C2 | 1.528 (3) | C32—H32 | 0.9500 |
C2—N1 | 1.288 (3) | C33—C34 | 1.377 (4) |
C2—C21 | 1.476 (3) | C33—H33 | 0.9500 |
C21—C22 | 1.392 (3) | C34—C35 | 1.395 (4) |
C21—C26 | 1.394 (3) | C34—H34 | 0.9500 |
C22—C23 | 1.390 (3) | C35—C36 | 1.382 (3) |
C22—H22 | 0.9500 | C35—H35 | 0.9500 |
C23—C24 | 1.377 (4) | C36—H36 | 0.9500 |
C16—C11—C12 | 119.5 (2) | C23—C24—C25 | 120.2 (2) |
C16—C11—C1 | 121.1 (2) | C23—C24—H24 | 119.9 |
C12—C11—C1 | 119.4 (2) | C25—C24—H24 | 119.9 |
C13—C12—C11 | 119.7 (2) | C24—C25—C26 | 120.2 (2) |
C13—C12—H12 | 120.1 | C24—C25—H25 | 119.9 |
C11—C12—H12 | 120.1 | C26—C25—H25 | 119.9 |
C12—C13—C14 | 120.3 (2) | C25—C26—C21 | 120.2 (2) |
C12—C13—H13 | 119.9 | C25—C26—H26 | 119.9 |
C14—C13—H13 | 119.9 | C21—C26—H26 | 119.9 |
C15—C14—C13 | 120.4 (2) | C2—N1—N2 | 110.84 (16) |
C15—C14—H14 | 119.8 | C3—N2—N1 | 111.29 (17) |
C13—C14—H14 | 119.8 | N2—C3—C31 | 121.5 (2) |
C14—C15—C16 | 119.8 (3) | N2—C3—H3 | 119.2 |
C14—C15—H15 | 120.1 | C31—C3—H3 | 119.2 |
C16—C15—H15 | 120.1 | C32—C31—C36 | 119.1 (2) |
C15—C16—C11 | 120.2 (2) | C32—C31—C3 | 119.3 (2) |
C15—C16—H16 | 119.9 | C36—C31—C3 | 121.6 (2) |
C11—C16—H16 | 119.9 | C31—C32—C33 | 120.4 (2) |
O1—C1—C11 | 122.96 (19) | C31—C32—H32 | 119.8 |
O1—C1—C2 | 117.85 (19) | C33—C32—H32 | 119.8 |
C11—C1—C2 | 119.19 (19) | C34—C33—C32 | 120.2 (2) |
N1—C2—C21 | 120.24 (19) | C34—C33—H33 | 119.9 |
N1—C2—C1 | 120.61 (18) | C32—C33—H33 | 119.9 |
C21—C2—C1 | 118.91 (18) | C33—C34—C35 | 120.1 (2) |
C22—C21—C26 | 118.99 (19) | C33—C34—H34 | 120.0 |
C22—C21—C2 | 120.9 (2) | C35—C34—H34 | 120.0 |
C26—C21—C2 | 120.1 (2) | C36—C35—C34 | 119.9 (2) |
C23—C22—C21 | 120.4 (2) | C36—C35—H35 | 120.0 |
C23—C22—H22 | 119.8 | C34—C35—H35 | 120.0 |
C21—C22—H22 | 119.8 | C35—C36—C31 | 120.3 (2) |
C24—C23—C22 | 120.0 (2) | C35—C36—H36 | 119.8 |
C24—C23—H23 | 120.0 | C31—C36—H36 | 119.8 |
C22—C23—H23 | 120.0 | ||
C16—C11—C12—C13 | 0.7 (3) | C2—C21—C22—C23 | −178.2 (2) |
C1—C11—C12—C13 | 179.7 (2) | C21—C22—C23—C24 | −0.4 (4) |
C11—C12—C13—C14 | 0.2 (4) | C22—C23—C24—C25 | −0.3 (4) |
C12—C13—C14—C15 | −1.0 (4) | C23—C24—C25—C26 | 0.8 (4) |
C13—C14—C15—C16 | 0.7 (5) | C24—C25—C26—C21 | −0.5 (4) |
C14—C15—C16—C11 | 0.2 (4) | C22—C21—C26—C25 | −0.2 (4) |
C12—C11—C16—C15 | −1.0 (3) | C2—C21—C26—C25 | 178.7 (2) |
C1—C11—C16—C15 | −179.9 (2) | C21—C2—N1—N2 | −178.27 (18) |
C16—C11—C1—O1 | 178.1 (2) | C1—C2—N1—N2 | −3.8 (3) |
C12—C11—C1—O1 | −0.8 (3) | C2—N1—N2—C3 | 179.9 (2) |
C16—C11—C1—C2 | −2.4 (3) | N1—N2—C3—C31 | 176.64 (19) |
C12—C11—C1—C2 | 178.7 (2) | N2—C3—C31—C32 | −180.0 (2) |
O1—C1—C2—N1 | −100.0 (2) | N2—C3—C31—C36 | −1.3 (3) |
C11—C1—C2—N1 | 80.6 (3) | C36—C31—C32—C33 | −1.4 (4) |
O1—C1—C2—C21 | 74.6 (3) | C3—C31—C32—C33 | 177.3 (2) |
C11—C1—C2—C21 | −104.9 (2) | C31—C32—C33—C34 | 1.5 (4) |
N1—C2—C21—C22 | −176.3 (2) | C32—C33—C34—C35 | −0.4 (4) |
C1—C2—C21—C22 | 9.1 (3) | C33—C34—C35—C36 | −0.7 (4) |
N1—C2—C21—C26 | 4.9 (3) | C34—C35—C36—C31 | 0.7 (4) |
C1—C2—C21—C26 | −169.7 (2) | C32—C31—C36—C35 | 0.4 (4) |
C26—C21—C22—C23 | 0.6 (4) | C3—C31—C36—C35 | −178.3 (2) |
Cg is the centroid of the C31–C36 phenyl ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C35—H35···O1i | 0.95 | 2.61 | 3.337 (3) | 134 |
C3—H3···O1ii | 0.95 | 2.41 | 3.272 (3) | 151 |
C32—H32···O1ii | 0.95 | 2.68 | 3.478 (3) | 141 |
C26—H26···Cgiii | 0.95 | 2.97 | 3.699 (3) | 135 |
Symmetry codes: (i) x, −y+1/2, −z+1/2; (ii) x+1/4, y−1/4, −z+3/4; (iii) x+1/4, −y+1/4, z+1/4. |
Acknowledgements
The authors acknowledge the Algerian Ministry of Higher Education and Scientific Research, the Algerian Directorate General for Scientific Research and Technological Development, and Ferhat Abbas Sétif 1 University for financial support. The Chemistry Department of the University of Otago is also thanked for support of the work of JS. Dr Lahcène Ouahab from the University of Rennes 1, France, is thanked for the data collection.
References
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