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

Ouari, K.; Merzougui, M.; Karmazin, L.

doi:10.1107/S2056989015014437

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Volume 71| Part 9| September 2015| Pages 1010-1012

https://doi.org/10.1107/S2056989015014437

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

Kamel Ouari,^a ^* Moufida Merzougui ^a and Lydia Karmazin ^b

^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.

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 imines 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 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, 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 and Table 1). 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	D⋯A	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
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

). 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 and Fig. 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

). 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 ,b ,c ). 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. 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 U_iso(H) = 1.2U_eq(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.

Table 2
Experimental details

Crystal data
Chemical formula	C₂₇H₂₆N₂O₂
M_r	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)
V (Å³)	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 )
T_min, T_max	0.792, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	5781, 1958, 1402
R_int	0.049
(sin θ/λ)_max (Å⁻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
Δρ_max, Δρ_min (e Å⁻³)	0.16, −0.14
Computer programs: COLLECT (Nonius, 1998 ), DENZO and SCALEPACK (Otwinowski & Minor, 1997 ), SHELXS2014 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015), Mercury (Macrae et al., 2008 ) and PLATON (Spek, 2009).

Supporting information

CCDC reference: 1416064

Crystal structure: contains datablocks I, Global. DOI: https://doi.org/10.1107/S2056989015014437/su5181sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015014437/su5181Isup2.hkl

checkCIF report

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

C₂₇H₂₆N₂O₂	F(000) = 436
M_r = 410.50	D_x = 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

Data collection top

Nonius KappaCCD diffractometer	1402 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.049
phi and ω scans	θ_max = 25.5°, θ_min = 2.9°
Absorption correction: multi-scan (MULSCAN in PLATON; Spek, 2009)	h = −25→23
T_min = 0.792, T_max = 1.000	k = −5→5
5781 measured reflections	l = −12→8
1958 independent reflections

Refinement top

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(F_o²) + (0.0549P)² + 0.0593P] where P = (F_o² + 2F_c²)/3
S = 1.08	(Δ/σ)_max < 0.001
1958 reflections	Δρ_max = 0.16 e Å⁻³
146 parameters	Δρ_min = −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)

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

	x	y	z	U_iso*/U_eq	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

Atomic displacement parameters (Å²) top

	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

Geometric parameters (Å, º) top

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.

Hydrogen-bond geometry (Å, º) top

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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