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Crystal structure of 1,1′-{(pentane-1,5-di­yl)bis­[(aza­niumylyl­­idene)methanylyl­­idene]}bis­(naphthalen-2-olate)

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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

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 23 July 2015; accepted 30 July 2015; online 6 August 2015)

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.

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[Alaghaz, A. M. A., Ammar, Y. A., Bayoumi, H. & Aldhlmani, S. A. (2014). J. Mol. Struct. 1074, 359-375.]; Kianfar et al., 2015[Kianfar, A. H., Mahmood, W. A. K., Dinari, M., Farrokhpour, H., Enteshari, M. & Azarian, M. H. (2015). Spectrochim. Acta A Mol. Biomol. Spectrosc. 136, 1582-1592.]; Mikhalyova et al., 2014[Mikhalyova, E. A., Yakovenko, A. V., Zeller, M., Gavrilenko, K. S., Lofland, S. E., Addison, A. W. & Pavlishchuk, V. V. (2014). Inorg. Chim. Acta, 414, 97-104.]; Borthakur et al., 2014[Borthakur, R., Kumar, A. & Lal, R. A. (2014). Spectrochim. Acta A Mol. Biomol. Spectrosc. 118, 94-101.]; Basumatary et al., 2015[Basumatary, D., Lal, R. A. & Kumar, A. (2015). J. Mol. Struct. 1092, 122-129.]). For many years, particular attention has been devoted to imines because of their uses as catalysts in various organic transformations (Khorshidifard et al., 2015[Khorshidifard, M., Rudbari, H. A., Askari, B., Sahihi, M., Farsani, M. R., Jalilian, F. & Bruno, G. (2015). Polyhedron, 95, 1-13.]), and for their anti­cancer (Shiju et al., 2015[Shiju, C., Arish, D., Bhuvanesh, N. & Kumaresan, S. (2015). Spectrochim. Acta A Mol. Biomol. Spectrosc. 145, 213-222.]), anti­fungal (Abo-Aly et al., 2015[Abo-Aly, M. M., Salem, A. M., Sayed, M. A. & Abdel Aziz, A. A. (2015). Spectrochim. Acta A Mol. Biomol. Spectrosc. 136, 993-1000.]) and anti­bacterial (Salehi et al., 2015[Salehi, M., Amoozadeh, A., Salamatmanesh, A., Kubicki, M., Dutkiewicz, G., Samiee, S. & Khaleghian, A. (2015). J. Mol. Struct. 1091, 81-87.]) properties. They have also been used as sensors (Bandi et al., 2013[Bandi, K. R., Singh, A. K. & Upadhyay, A. (2013). Electrochim. Acta, 105, 654-664.]), corrosion inhibitors (Dasami et al., 2015[Dasami, P. M., Parameswari, K. & Chitra, S. (2015). Measurement, 69, 195-201.]) and optical and fluorescent probes (Shoora et al., 2015[Shoora, S. K., Jain, A. K. & Gupta, V. K. (2015). Sens. Actuators B Chem. 216, 86-104.]; Prabhakara et al., 2015[Prabhakara, C. T., Patil, S. A., Kulkarni, A. D., Naik, V. A., Manjunatha, M., Kinnal, S. M. & Badami, P. S. (2015). J. Photochem. Photobiol. B, 148, 322-332.]).

[Scheme 1]

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[Jeux, V., Segut, O., Demeter, D., Rousseau, T., Allain, M., Dalinot, C., Sanguinet, L., Leriche, P. & Roncali, J. (2015). Dyes Pigments, 113, 402-408.]), or the synthesis of a series of acyclic Schiff base–chromium(III) complexes (Kumar et al., 2015[Kumar, S. P., Suresh, R., Giribabu, K., Manigandan, R., Munusamy, S., Muthamizh, S. & Narayanan, V. (2015). Spectrochim. Acta A Mol. Biomol. Spectrosc. 139, 431-441.]).

In a continuation of our work on Schiff base ligands, we report herein on the crystal structure of the title compound, synthesized using two methods, viz. microwave irradiation and conventional, by condensing o-hy­droxy­naphthaldehyde and 1,5-di­amino­pentane.

2. Structural commentary

The whole mol­ecule of the title compound, Fig. 1[link], 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 + [{1\over 2}]], forming S(6) ring motifs (Fig. 1[link] and Table 1[link]). The pentyl chain has an extended conformation with the naphthalene rings inclined to one another by 89.94 (5)°.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N⋯O1 0.96 (2) 1.72 (2) 2.5437 (17) 141.3 (16)
C12—H12A⋯O1i 0.99 2.45 3.2871 (19) 142
Symmetry code: (i) [x, -y+1, z+{\script{1\over 2}}].
[Figure 1]
Figure 1
The mol­ecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level. The intra­molecular hydrogen bonds are shown as dashed lines (see Table 1[link]). The unlabelled atoms are related to the labelled atoms by twofold rotational symmetry (atom C14 lies on the twofold axis; symmetry code: −x, y, −z + [{1\over 2}]).

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[link] and Fig. 2[link]).

[Figure 2]
Figure 2
Crystal packing of the title compound viewed along the b axis. The hydrogen bonds are shown as dashed lines (see Table 1[link]). For clarity, only the H atoms involved in hydrogen bonding have been included.

4. Database survey

Recently, our group reported the crystal structures of three new Schiff bases synthesized using conventional or ultrasonic irradiation methods by reacting primary amines and o-hy­droxy­naphthaldehyde (Ouari et al., 2015a[Ouari, K., Bendia, S., Weiss, J. & Bailly, C. (2015a). Spectrochim. Acta Part A, 135, 624-631.],b[Ouari, K., Bendia, S., Merzougui, M. & Bailly, C. (2015b). Acta Cryst. E71, o51-o52.],c[Ouari, K., Merzougui, M., Bendia, S. & Bailly, C. (2015c). Acta Cryst. E71, o351-o352.]). They too crystallize as bis-zwitterionic compounds with strong intra­molecular N—H⋯O hydrogen bonds forming S(6) ring motifs.

5. 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 diffraction analysis, 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 refinement details are summarized in Table 2[link]. 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[Sheldrick, G. M. (2015). Acta Cryst. A71, 3-8.]); the occupancy of the methyl­ene H atoms were fixed automatically at 0.5.

Table 2
Experimental details

Crystal data
Chemical formula C27H26N2O2
Mr 410.50
Crystal system, space group Monoclinic, P2/c
Temperature (K) 173
a, b, c (Å) 20.9080 (13), 4.7429 (2), 10.6810 (6)
β (°) 96.419 (3)
V3) 1052.54 (10)
Z 2
Radiation type Mo Kα
μ (mm−1) 0.08
Crystal size (mm) 0.45 × 0.20 × 0.10
 
Data collection
Diffractometer Nonius KappaCCD
Absorption correction Multi-scan (MULSCAN in PLATON; Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.])
Tmin, Tmax 0.792, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 5781, 1958, 1402
Rint 0.049
(sin θ/λ)max−1) 0.606
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.120, 1.08
No. of reflections 1958
No. of parameters 146
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.16, −0.14
Computer programs: COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands.]), DENZO and SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]), SHELXS2014 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. A71, 3-8.]), Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: 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).

1,1'-{(Pentane-1,5-diyl)bis[(azaniumylylidene)methanylylidene]}bis(naphthalen-2-olate) top
Crystal data top
C27H26N2O2F(000) = 436
Mr = 410.50Dx = 1.295 Mg m3
Monoclinic, P2/cMo Kα radiation, λ = 0.71073 Å
a = 20.9080 (13) ÅCell parameters from 7575 reflections
b = 4.7429 (2) Åθ = 1.0–27.5°
c = 10.6810 (6) ŵ = 0.08 mm1
β = 96.419 (3)°T = 173 K
V = 1052.54 (10) Å3Plate, yellow
Z = 20.45 × 0.20 × 0.10 mm
Data collection top
Nonius KappaCCD
diffractometer
1402 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.049
phi and ω scansθmax = 25.5°, θmin = 2.9°
Absorption correction: multi-scan
(MULSCAN in PLATON; Spek, 2009)
h = 2523
Tmin = 0.792, Tmax = 1.000k = 55
5781 measured reflectionsl = 128
1958 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.049H 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 reflectionsΔρmax = 0.16 e Å3
146 parametersΔρmin = 0.14 e Å3
0 restraintsExtinction correction: SHELXL2014 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.033 (7)
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.14942 (5)0.8929 (2)0.10611 (10)0.0508 (4)
N10.13436 (6)0.5012 (3)0.05060 (12)0.0436 (4)
H1N0.1201 (8)0.643 (4)0.0110 (19)0.080 (6)*
C10.21054 (7)0.8695 (3)0.07692 (14)0.0412 (4)
C20.25371 (8)1.0411 (3)0.13960 (15)0.0497 (5)
H20.23641.17080.20220.060*
C30.31790 (9)1.0235 (3)0.11224 (17)0.0546 (5)
H30.34461.14130.15620.065*
C40.34731 (8)0.8329 (3)0.01900 (15)0.0469 (4)
C50.41450 (8)0.8204 (4)0.00866 (18)0.0612 (5)
H50.44070.93830.03620.073*
C60.44291 (8)0.6423 (4)0.09873 (19)0.0632 (5)
H60.48840.63650.11690.076*
C70.40413 (8)0.4698 (4)0.16322 (18)0.0589 (5)
H70.42350.34460.22580.071*
C80.33846 (7)0.4769 (3)0.13821 (16)0.0508 (5)
H80.31320.35660.18410.061*
C90.30745 (7)0.6580 (3)0.04622 (14)0.0403 (4)
C100.23834 (7)0.6743 (3)0.01610 (13)0.0377 (4)
C110.19669 (7)0.4956 (3)0.07450 (14)0.0405 (4)
H110.21520.36350.13480.049*
C120.09067 (7)0.3217 (3)0.11165 (15)0.0440 (4)
H12A0.11590.19030.16990.053*
H12B0.06440.20830.04720.053*
C130.04669 (7)0.4962 (3)0.18441 (15)0.0454 (4)
H13A0.02190.62810.12570.054*
H13B0.07330.61000.24820.054*
C140.00000.3185 (4)0.25000.0449 (6)
H14A0.02470.19560.18710.054*0.5
H14B0.02470.19550.31290.054*0.5
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0484 (7)0.0583 (7)0.0443 (7)0.0043 (5)0.0014 (5)0.0039 (5)
N10.0412 (8)0.0500 (8)0.0395 (8)0.0013 (6)0.0038 (6)0.0011 (6)
C10.0460 (9)0.0454 (9)0.0314 (8)0.0001 (7)0.0015 (7)0.0083 (7)
C20.0615 (12)0.0473 (9)0.0399 (10)0.0025 (8)0.0040 (8)0.0025 (7)
C30.0581 (11)0.0563 (10)0.0504 (11)0.0114 (8)0.0112 (9)0.0009 (8)
C40.0462 (10)0.0501 (10)0.0442 (10)0.0049 (8)0.0049 (7)0.0107 (8)
C50.0470 (11)0.0745 (12)0.0629 (12)0.0127 (9)0.0096 (9)0.0054 (10)
C60.0395 (10)0.0817 (13)0.0674 (13)0.0006 (9)0.0010 (9)0.0129 (11)
C70.0472 (10)0.0683 (12)0.0587 (12)0.0052 (9)0.0051 (9)0.0027 (9)
C80.0434 (10)0.0578 (10)0.0501 (11)0.0005 (8)0.0008 (8)0.0002 (8)
C90.0416 (9)0.0435 (9)0.0356 (9)0.0006 (7)0.0042 (7)0.0103 (7)
C100.0402 (8)0.0405 (8)0.0322 (8)0.0008 (7)0.0038 (7)0.0059 (6)
C110.0407 (9)0.0446 (9)0.0352 (9)0.0049 (7)0.0002 (7)0.0047 (7)
C120.0405 (9)0.0463 (9)0.0450 (10)0.0027 (7)0.0035 (7)0.0002 (7)
C130.0415 (9)0.0479 (9)0.0467 (10)0.0006 (7)0.0049 (7)0.0007 (7)
C140.0375 (12)0.0466 (12)0.0502 (14)0.0000.0023 (10)0.000
Geometric parameters (Å, º) top
O1—C11.2858 (17)C7—C81.369 (2)
N1—C111.2999 (19)C7—H70.9500
N1—C121.4551 (19)C8—C91.408 (2)
N1—H1N0.96 (2)C8—H80.9500
C1—C101.433 (2)C9—C101.447 (2)
C1—C21.435 (2)C10—C111.410 (2)
C2—C31.344 (2)C11—H110.9500
C2—H20.9500C12—C131.515 (2)
C3—C41.432 (2)C12—H12A0.9900
C3—H30.9500C12—H12B0.9900
C4—C51.404 (2)C13—C141.5191 (18)
C4—C91.413 (2)C13—H13A0.9900
C5—C61.365 (3)C13—H13B0.9900
C5—H50.9500C14—C13i1.5190 (18)
C6—C71.388 (3)C14—H14A0.9900
C6—H60.9500C14—H14B0.9900
C11—N1—C12124.46 (14)C8—C9—C4116.82 (14)
C11—N1—H1N112.0 (11)C8—C9—C10123.95 (14)
C12—N1—H1N123.5 (11)C4—C9—C10119.23 (14)
O1—C1—C10122.62 (14)C11—C10—C1118.19 (14)
O1—C1—C2119.85 (14)C11—C10—C9121.36 (14)
C10—C1—C2117.52 (14)C1—C10—C9120.43 (13)
C3—C2—C1121.89 (16)N1—C11—C10123.79 (14)
C3—C2—H2119.1N1—C11—H11118.1
C1—C2—H2119.1C10—C11—H11118.1
C2—C3—C4122.09 (16)N1—C12—C13110.97 (12)
C2—C3—H3119.0N1—C12—H12A109.4
C4—C3—H3119.0C13—C12—H12A109.4
C5—C4—C9120.18 (16)N1—C12—H12B109.4
C5—C4—C3120.99 (16)C13—C12—H12B109.4
C9—C4—C3118.83 (15)H12A—C12—H12B108.0
C6—C5—C4121.37 (17)C12—C13—C14113.06 (12)
C6—C5—H5119.3C12—C13—H13A109.0
C4—C5—H5119.3C14—C13—H13A109.0
C5—C6—C7118.82 (17)C12—C13—H13B109.0
C5—C6—H6120.6C14—C13—H13B109.0
C7—C6—H6120.6H13A—C13—H13B107.8
C8—C7—C6121.16 (18)C13i—C14—C13112.58 (17)
C8—C7—H7119.4C13i—C14—H14A109.1
C6—C7—H7119.4C13—C14—H14A109.1
C7—C8—C9121.65 (16)C13i—C14—H14B109.1
C7—C8—H8119.2C13—C14—H14B109.1
C9—C8—H8119.2H14A—C14—H14B107.8
O1—C1—C2—C3179.92 (15)C3—C4—C9—C100.6 (2)
C10—C1—C2—C30.6 (2)O1—C1—C10—C112.0 (2)
C1—C2—C3—C40.0 (3)C2—C1—C10—C11177.25 (12)
C2—C3—C4—C5179.42 (16)O1—C1—C10—C9179.47 (13)
C2—C3—C4—C90.0 (2)C2—C1—C10—C91.2 (2)
C9—C4—C5—C60.4 (3)C8—C9—C10—C113.1 (2)
C3—C4—C5—C6179.02 (17)C4—C9—C10—C11177.16 (13)
C4—C5—C6—C70.4 (3)C8—C9—C10—C1178.51 (14)
C5—C6—C7—C80.3 (3)C4—C9—C10—C11.3 (2)
C6—C7—C8—C90.2 (3)C12—N1—C11—C10178.86 (13)
C7—C8—C9—C40.2 (2)C1—C10—C11—N11.3 (2)
C7—C8—C9—C10179.94 (15)C9—C10—C11—N1179.82 (13)
C5—C4—C9—C80.3 (2)C11—N1—C12—C13117.93 (15)
C3—C4—C9—C8179.15 (13)N1—C12—C13—C14179.96 (11)
C5—C4—C9—C10179.95 (14)C12—C13—C14—C13i176.30 (15)
Symmetry code: (i) x, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O10.96 (2)1.72 (2)2.5437 (17)141.3 (16)
C12—H12A···O1ii0.992.453.2871 (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.

References

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