research communications
of 1,1′-{(pentane-1,5-diyl)bis[(azaniumylylidene)methanylylidene]}bis(naphthalen-2-olate)
aLaboratoire d'lectrochimie, d'Ingénierie Moléculaire et de Catalyse Redox, Faculty of Technology, University of Ferhat Abbas Sétif-1, 19000 Sétif, Algeria, and bService de Radiocristallographie, Institut de Chimie UMR 7177 CNRS-Université de Strasbourg, 1 rue Blaise Pascal, BP296/R8, 67008 Strasbourg Cedex, France
*Correspondence e-mail: k_ouari@yahoo.fr
The whole molecule of the title compound, C27H26N2O2, is generated by twofold rotational symmetry, with the central C atom of the pentyl chain located on the twofold rotation axis. The compound crystallizes as a bis-zwitterion, and there are two intramolecular N—H⋯O hydrogen bonds generating S(6) ring motifs. In the crystal, molecules are linked by pairs of C—H⋯O hydrogen bonds, forming ribbons propagating along [001], and enclosing R22(22) ring motifs.
Keywords: crystal structure; 1,5-diaminopentane; 2-hydroxy-1-naphthaldehyde; zwitterion; bis-zwitterion; hydrogen bonding.
CCDC reference: 1416064
1. Chemical context
Tetradentate NNOO Schiff-bases have been used extensively as supporting ligands in d-block chemistry because of their ability to stabilize metals in various oxidation states (Alaghaz et al., 2014; Kianfar et al., 2015; Mikhalyova et al., 2014; Borthakur et al., 2014; Basumatary et al., 2015). For many years, particular attention has been devoted to because of their uses as catalysts in various organic transformations (Khorshidifard et al., 2015), and for their anticancer (Shiju et al., 2015), antifungal (Abo-Aly et al., 2015) and antibacterial (Salehi et al., 2015) properties. They have also been used as sensors (Bandi et al., 2013), corrosion inhibitors (Dasami et al., 2015) and optical and fluorescent probes (Shoora et al., 2015; Prabhakara et al., 2015).
The microwave-assisted synthesis method, in solvent or solvent-free, is efficient and rapid. It gives cleaner reactions, is ease to use, gives higher yields and is a more economical synthetic process for the preparation of Schiff base compounds compared to conventional methods. It has been used to enhance the yield and reduce the time of certain reactions: for example, a one-step synthesis of D-A-D chromophores as active materials for organic solar cells (Jeux et al., 2015), or the synthesis of a series of acyclic Schiff base–chromium(III) complexes (Kumar et al., 2015).
In a continuation of our work on Schiff base ligands, we report herein on the viz. microwave irradiation and conventional, by condensing o-hydroxynaphthaldehyde and 1,5-diaminopentane.
of the title compound, synthesized using two methods,2. Structural commentary
The whole molecule of the title compound, Fig. 1, is generated by twofold rotational symmetry, with the central C atom of the pentyl chain, C14, located on the twofold rotation axis. It crystallizes as a bis-zwitterion, with strong intramolecular N—H⋯O hydrogen bonding between the imino N atom N1 (N1'), and the O atom, O1 (O1i) [d (O⋯N) = 2.5437 (17) Å; symmetry code: (i) −x, y, −z + ], forming S(6) ring motifs (Fig. 1 and Table 1). The pentyl chain has an extended conformation with the naphthalene rings inclined to one another by 89.94 (5)°.
3. Supramolecular features
In the crystal, molecules are linked by pairs of C—H⋯O hydrogen bonds, forming ribbons propagating along [001] and enclosing R22(22) ring motifs (Table 1 and Fig. 2).
4. Database survey
Recently, our group reported the crystal structures of three new o-hydroxynaphthaldehyde (Ouari et al., 2015a,b,c). They too crystallize as bis-zwitterionic compounds with strong intramolecular N—H⋯O hydrogen bonds forming S(6) ring motifs.
synthesized using conventional or ultrasonic irradiation methods by reacting primary and5. Synthesis and crystallization
Method 1: Microwave synthesis
2-Hydroxy-1-naphthaldehyde (0.344g, 2 mmol), mixed and ground in a mortar, was placed in a reaction flask, and then 1,5-diaminopentane (0.109 g, 1 mmol) in 2 ml of methanol was added. The reaction mixture was then irradiated in a microwave oven for 1 min at 600 W. Upon completion, based on TLC analysis (silica gel, CH2Cl2/MeOH, 9.5/0.5, v/v), the product was washed with methanol (3 × 3 ml) and diethyl ether (3 × 3 ml) and filtered. Yellow crystals of the title compound, suitable for X-ray were obtained after two days by slow evaporation of a solution in DMSO/MeOH (yield: 95%, m.p.: 438–440 K). Elemental analysis calculated for C27H26N2O2: C, 80.00; H, 6.38; N,6.82%; found: C, 80.42; H, 6.63; N, 6.56%.
Method 2: Conventional synthesis
The title Schiff base was prepared by condensation between 1,5-diaminopentane (51 mg, 0.5 mmol) and 2-hydroxy-1-naphthaldehyde (172 mg, 1 mmol) in methanol (10 ml). The mixture was refluxed and stirred under a nitrogen atmosphere for 3 h. The precipitate obtained was filtered, washed with methanol and diethyl ether and dried in vacuum overnight. Yellow single crystals of the title compound were obtained by slow evaporation of a solution in methanol (yield 71%; m.p.: 438–440 K).
As expected, the yield using method 1 (95%) is significantly greater than that using method 2 (71%).
6. Refinement
Crystal data, data collection and structure . The iminium H atom was located from a difference Fourier map and freely refined. C-bound H atoms were included in calculated positions and treated as riding atoms: C—H = 0.95 − 0.99 Å with Uiso(H) = 1.2Ueq(C). Atom C14 lies on the twofold rotation axis and the H atoms were placed using instruction HFIX 23 (Sheldrick, 2015); the occupancy of the methylene H atoms were fixed automatically at 0.5.
details are summarized in Table 2Supporting information
CCDC reference: 1416064
https://doi.org/10.1107/S2056989015014437/su5181sup1.cif
contains datablocks I, Global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015014437/su5181Isup2.hkl
Data collection: COLLECT (Nonius, 1998); cell
SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015) and PLATON (Spek, 2009).C27H26N2O2 | F(000) = 436 |
Mr = 410.50 | Dx = 1.295 Mg m−3 |
Monoclinic, P2/c | Mo Kα radiation, λ = 0.71073 Å |
a = 20.9080 (13) Å | Cell parameters from 7575 reflections |
b = 4.7429 (2) Å | θ = 1.0–27.5° |
c = 10.6810 (6) Å | µ = 0.08 mm−1 |
β = 96.419 (3)° | T = 173 K |
V = 1052.54 (10) Å3 | Plate, yellow |
Z = 2 | 0.45 × 0.20 × 0.10 mm |
Nonius KappaCCD diffractometer | 1402 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.049 |
phi and ω scans | θmax = 25.5°, θmin = 2.9° |
Absorption correction: multi-scan (MULSCAN in PLATON; Spek, 2009) | h = −25→23 |
Tmin = 0.792, Tmax = 1.000 | k = −5→5 |
5781 measured reflections | l = −12→8 |
1958 independent reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.049 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.120 | w = 1/[σ2(Fo2) + (0.0549P)2 + 0.0593P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max < 0.001 |
1958 reflections | Δρmax = 0.16 e Å−3 |
146 parameters | Δρmin = −0.14 e Å−3 |
0 restraints | Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.033 (7) |
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 | Occ. (<1) | |
O1 | 0.14942 (5) | 0.8929 (2) | −0.10611 (10) | 0.0508 (4) | |
N1 | 0.13436 (6) | 0.5012 (3) | 0.05060 (12) | 0.0436 (4) | |
H1N | 0.1201 (8) | 0.643 (4) | −0.0110 (19) | 0.080 (6)* | |
C1 | 0.21054 (7) | 0.8695 (3) | −0.07692 (14) | 0.0412 (4) | |
C2 | 0.25371 (8) | 1.0411 (3) | −0.13960 (15) | 0.0497 (5) | |
H2 | 0.2364 | 1.1708 | −0.2022 | 0.060* | |
C3 | 0.31790 (9) | 1.0235 (3) | −0.11224 (17) | 0.0546 (5) | |
H3 | 0.3446 | 1.1413 | −0.1562 | 0.065* | |
C4 | 0.34731 (8) | 0.8329 (3) | −0.01900 (15) | 0.0469 (4) | |
C5 | 0.41450 (8) | 0.8204 (4) | 0.00866 (18) | 0.0612 (5) | |
H5 | 0.4407 | 0.9383 | −0.0362 | 0.073* | |
C6 | 0.44291 (8) | 0.6423 (4) | 0.09873 (19) | 0.0632 (5) | |
H6 | 0.4884 | 0.6365 | 0.1169 | 0.076* | |
C7 | 0.40413 (8) | 0.4698 (4) | 0.16322 (18) | 0.0589 (5) | |
H7 | 0.4235 | 0.3446 | 0.2258 | 0.071* | |
C8 | 0.33846 (7) | 0.4769 (3) | 0.13821 (16) | 0.0508 (5) | |
H8 | 0.3132 | 0.3566 | 0.1841 | 0.061* | |
C9 | 0.30745 (7) | 0.6580 (3) | 0.04622 (14) | 0.0403 (4) | |
C10 | 0.23834 (7) | 0.6743 (3) | 0.01610 (13) | 0.0377 (4) | |
C11 | 0.19669 (7) | 0.4956 (3) | 0.07450 (14) | 0.0405 (4) | |
H11 | 0.2152 | 0.3635 | 0.1348 | 0.049* | |
C12 | 0.09067 (7) | 0.3217 (3) | 0.11165 (15) | 0.0440 (4) | |
H12A | 0.1159 | 0.1903 | 0.1699 | 0.053* | |
H12B | 0.0644 | 0.2083 | 0.0472 | 0.053* | |
C13 | 0.04669 (7) | 0.4962 (3) | 0.18441 (15) | 0.0454 (4) | |
H13A | 0.0219 | 0.6281 | 0.1257 | 0.054* | |
H13B | 0.0733 | 0.6100 | 0.2482 | 0.054* | |
C14 | 0.0000 | 0.3185 (4) | 0.2500 | 0.0449 (6) | |
H14A | −0.0247 | 0.1956 | 0.1871 | 0.054* | 0.5 |
H14B | 0.0247 | 0.1955 | 0.3129 | 0.054* | 0.5 |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0484 (7) | 0.0583 (7) | 0.0443 (7) | 0.0043 (5) | −0.0014 (5) | 0.0039 (5) |
N1 | 0.0412 (8) | 0.0500 (8) | 0.0395 (8) | 0.0013 (6) | 0.0038 (6) | 0.0011 (6) |
C1 | 0.0460 (9) | 0.0454 (9) | 0.0314 (8) | 0.0001 (7) | 0.0015 (7) | −0.0083 (7) |
C2 | 0.0615 (12) | 0.0473 (9) | 0.0399 (10) | −0.0025 (8) | 0.0040 (8) | 0.0025 (7) |
C3 | 0.0581 (11) | 0.0563 (10) | 0.0504 (11) | −0.0114 (8) | 0.0112 (9) | 0.0009 (8) |
C4 | 0.0462 (10) | 0.0501 (10) | 0.0442 (10) | −0.0049 (8) | 0.0049 (7) | −0.0107 (8) |
C5 | 0.0470 (11) | 0.0745 (12) | 0.0629 (12) | −0.0127 (9) | 0.0096 (9) | −0.0054 (10) |
C6 | 0.0395 (10) | 0.0817 (13) | 0.0674 (13) | −0.0006 (9) | 0.0010 (9) | −0.0129 (11) |
C7 | 0.0472 (10) | 0.0683 (12) | 0.0587 (12) | 0.0052 (9) | −0.0051 (9) | −0.0027 (9) |
C8 | 0.0434 (10) | 0.0578 (10) | 0.0501 (11) | 0.0005 (8) | 0.0008 (8) | −0.0002 (8) |
C9 | 0.0416 (9) | 0.0435 (9) | 0.0356 (9) | −0.0006 (7) | 0.0042 (7) | −0.0103 (7) |
C10 | 0.0402 (8) | 0.0405 (8) | 0.0322 (8) | −0.0008 (7) | 0.0038 (7) | −0.0059 (6) |
C11 | 0.0407 (9) | 0.0446 (9) | 0.0352 (9) | 0.0049 (7) | −0.0002 (7) | −0.0047 (7) |
C12 | 0.0405 (9) | 0.0463 (9) | 0.0450 (10) | −0.0027 (7) | 0.0035 (7) | −0.0002 (7) |
C13 | 0.0415 (9) | 0.0479 (9) | 0.0467 (10) | −0.0006 (7) | 0.0049 (7) | 0.0007 (7) |
C14 | 0.0375 (12) | 0.0466 (12) | 0.0502 (14) | 0.000 | 0.0023 (10) | 0.000 |
O1—C1 | 1.2858 (17) | C7—C8 | 1.369 (2) |
N1—C11 | 1.2999 (19) | C7—H7 | 0.9500 |
N1—C12 | 1.4551 (19) | C8—C9 | 1.408 (2) |
N1—H1N | 0.96 (2) | C8—H8 | 0.9500 |
C1—C10 | 1.433 (2) | C9—C10 | 1.447 (2) |
C1—C2 | 1.435 (2) | C10—C11 | 1.410 (2) |
C2—C3 | 1.344 (2) | C11—H11 | 0.9500 |
C2—H2 | 0.9500 | C12—C13 | 1.515 (2) |
C3—C4 | 1.432 (2) | C12—H12A | 0.9900 |
C3—H3 | 0.9500 | C12—H12B | 0.9900 |
C4—C5 | 1.404 (2) | C13—C14 | 1.5191 (18) |
C4—C9 | 1.413 (2) | C13—H13A | 0.9900 |
C5—C6 | 1.365 (3) | C13—H13B | 0.9900 |
C5—H5 | 0.9500 | C14—C13i | 1.5190 (18) |
C6—C7 | 1.388 (3) | C14—H14A | 0.9900 |
C6—H6 | 0.9500 | C14—H14B | 0.9900 |
C11—N1—C12 | 124.46 (14) | C8—C9—C4 | 116.82 (14) |
C11—N1—H1N | 112.0 (11) | C8—C9—C10 | 123.95 (14) |
C12—N1—H1N | 123.5 (11) | C4—C9—C10 | 119.23 (14) |
O1—C1—C10 | 122.62 (14) | C11—C10—C1 | 118.19 (14) |
O1—C1—C2 | 119.85 (14) | C11—C10—C9 | 121.36 (14) |
C10—C1—C2 | 117.52 (14) | C1—C10—C9 | 120.43 (13) |
C3—C2—C1 | 121.89 (16) | N1—C11—C10 | 123.79 (14) |
C3—C2—H2 | 119.1 | N1—C11—H11 | 118.1 |
C1—C2—H2 | 119.1 | C10—C11—H11 | 118.1 |
C2—C3—C4 | 122.09 (16) | N1—C12—C13 | 110.97 (12) |
C2—C3—H3 | 119.0 | N1—C12—H12A | 109.4 |
C4—C3—H3 | 119.0 | C13—C12—H12A | 109.4 |
C5—C4—C9 | 120.18 (16) | N1—C12—H12B | 109.4 |
C5—C4—C3 | 120.99 (16) | C13—C12—H12B | 109.4 |
C9—C4—C3 | 118.83 (15) | H12A—C12—H12B | 108.0 |
C6—C5—C4 | 121.37 (17) | C12—C13—C14 | 113.06 (12) |
C6—C5—H5 | 119.3 | C12—C13—H13A | 109.0 |
C4—C5—H5 | 119.3 | C14—C13—H13A | 109.0 |
C5—C6—C7 | 118.82 (17) | C12—C13—H13B | 109.0 |
C5—C6—H6 | 120.6 | C14—C13—H13B | 109.0 |
C7—C6—H6 | 120.6 | H13A—C13—H13B | 107.8 |
C8—C7—C6 | 121.16 (18) | C13i—C14—C13 | 112.58 (17) |
C8—C7—H7 | 119.4 | C13i—C14—H14A | 109.1 |
C6—C7—H7 | 119.4 | C13—C14—H14A | 109.1 |
C7—C8—C9 | 121.65 (16) | C13i—C14—H14B | 109.1 |
C7—C8—H8 | 119.2 | C13—C14—H14B | 109.1 |
C9—C8—H8 | 119.2 | H14A—C14—H14B | 107.8 |
O1—C1—C2—C3 | −179.92 (15) | C3—C4—C9—C10 | 0.6 (2) |
C10—C1—C2—C3 | −0.6 (2) | O1—C1—C10—C11 | 2.0 (2) |
C1—C2—C3—C4 | 0.0 (3) | C2—C1—C10—C11 | −177.25 (12) |
C2—C3—C4—C5 | −179.42 (16) | O1—C1—C10—C9 | −179.47 (13) |
C2—C3—C4—C9 | 0.0 (2) | C2—C1—C10—C9 | 1.2 (2) |
C9—C4—C5—C6 | −0.4 (3) | C8—C9—C10—C11 | −3.1 (2) |
C3—C4—C5—C6 | 179.02 (17) | C4—C9—C10—C11 | 177.16 (13) |
C4—C5—C6—C7 | 0.4 (3) | C8—C9—C10—C1 | 178.51 (14) |
C5—C6—C7—C8 | −0.3 (3) | C4—C9—C10—C1 | −1.3 (2) |
C6—C7—C8—C9 | 0.2 (3) | C12—N1—C11—C10 | −178.86 (13) |
C7—C8—C9—C4 | −0.2 (2) | C1—C10—C11—N1 | −1.3 (2) |
C7—C8—C9—C10 | −179.94 (15) | C9—C10—C11—N1 | −179.82 (13) |
C5—C4—C9—C8 | 0.3 (2) | C11—N1—C12—C13 | 117.93 (15) |
C3—C4—C9—C8 | −179.15 (13) | N1—C12—C13—C14 | 179.96 (11) |
C5—C4—C9—C10 | −179.95 (14) | C12—C13—C14—C13i | −176.30 (15) |
Symmetry code: (i) −x, y, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1 | 0.96 (2) | 1.72 (2) | 2.5437 (17) | 141.3 (16) |
C12—H12A···O1ii | 0.99 | 2.45 | 3.2871 (19) | 142 |
Symmetry code: (ii) x, −y+1, z+1/2. |
Acknowledgements
The authors gratefully acknowledge financial support from the Algerian Ministry of Higher Education and Scientific Research. They also acknowledge the help of Dr Jean Weiss from the CLAC laboratory at the Institut de Chimie, Université de Strasbourg, France.
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