N,N′-Bis(2-hydr­oxy-3-eth­oxybenzyl­idene)butane-1,4-diamine

Fun, H.-K.; Kia, R.; Kargar, H.; Jamshidvand, A.

doi:10.1107/S1600536809007545

organic compounds

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ISSN: 2056-9890

Volume 65| Part 4| April 2009| Page o706

doi:10.1107/S1600536809007545

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N,N′-Bis(2-hydroxy-3-ethoxybenzylidene)butane-1,4-diamine

Hoong-Kun Fun,^a ^* Reza Kia,^a ‡ Hadi Kargar ^b and Arezoo Jamshidvand ^b

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and ^bDepartment of Chemistry, School of Science, Payame Noor University (PNU), Ardakan, Yazd, Iran
^*Correspondence e-mail: hkfun@usm.my

(Received 27 February 2009; accepted 2 March 2009; online 6 March 2009)

The title Schiff base compound, C₂₂H₂₈N₂O₄, lies across a crystallographic inversion centre and adopts an E configuration with respect to the C=N bond. Pairs of weak intermolecular C—H⋯O interactions link neighbouring molecules into dimers with an R²₂(28) ring motif. The crystal structure is stabilized by intermolecular C—H⋯π interactions. An intramolecular O—H⋯N hydrogen bond occurs.

Related literature

For hydrogen-bond motifs, see: Bernstein et al. (1995 ). For information on Schiff base ligands and complexes and their applications, see, for example: Calligaris & Randaccio (1987 ); Casellato & Vigato (1977 ); Fun & Kia (2008a ,b ). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 ).

Experimental

Crystal data

C₂₂H₂₈N₂O₄
M_r = 384.46
Triclinic, $[P \overline 1]$
a = 6.8647 (2) Å
b = 6.9052 (2) Å
c = 10.8083 (3) Å
α = 92.779 (2)°
β = 99.908 (2)°
γ = 101.239 (2)°
V = 493.23 (2) Å³
Z = 1
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 100 K
0.45 × 0.19 × 0.07 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.961, T_max = 0.994
8962 measured reflections
2954 independent reflections
2157 reflections with I > 2σ(I)
R_int = 0.033

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.131
S = 1.04
2954 reflections
129 parameters
H-atom parameters constrained
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.84	1.82	2.5638 (14)	147
C5—H5A⋯O1ⁱ	0.95	2.59	3.2268 (14)	125
C11—H11B⋯Cg1ⁱⁱ	0.98	2.96	3.5403 (15)	145
Symmetry codes: (i) x, y-1, z; (ii) -x+2, -y+1, -z+1. Cg1 is the centroid of the C1–C6 benzene ring.

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809007545/at2734sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809007545/at2734Isup2.hkl

checkCIF report

Comment top

The condensation of primary amines with carbonyl compounds yields Schiff base (Casellato & Vigato, 1977) that are still one of the most prevalent mixed-donor ligands in coordination chemistry. In the past two decades, the synthesis, structure and properties of Schiff base complexes have stimulated much interest for their noteworthy contributions in single molecule-based magnetism, materials science, catalysis of many reactions like carbonylation, hydroformylation, reduction, oxidation, epoxidation and hydrolysis (Casellato & Vigato 1977). In comparison to the Schiff base metal complexes, only a relatively small number of free Schiff base ligands have been characterized (Calligaris & Randaccio, 1987). As an extension of our work (Fun & Kia 2008a,b) on the structural characterization of Schiff base ligands, the title compound is reported here.

The molecule of the title compound, Fig 1, lies across a crystallographic inversion centre and adopts an E configuration with respect to the azomethine (C═N) bond. The asymmetric unit of the compound is composed of one-half of the molecule. The imino group is coplanar with the benzene ring. Pairs of intermolecular C—H···O interactions link neighbouring molecules into dimers with a R²₂(28) ring motif (Bernstein et al., 1995). The crystal structure is stabilized by intermolecular C—H···π interactions [Cg1 is the centroid of the C1–C6 benzene ring] (Table 1).

Related literature top

For hydrogen-bond motifs, see: Bernstein et al. (1995). For information on Schiff base ligands and complexes and their applications, see, for example: Calligaris & Randaccio (1987); Casellato & Vigato (1977); Fun & Kia (2008a,b). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986). Cg1 is the centroid of the C1–C6 benzene ring.

Experimental top

The synthetic method has been described earlier (Fun, Kia & Kargar et al., 2008b), except that 2-hydroxy-3-ethoxysalicylaldehyde was used . Single crystals suitable for X-ray diffraction were obtained by evaporation of an ethanol solution at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound with atom labels and 50% probability ellipsoids for non-H atoms. The suffix A corresponds to symmetry code (-x + 2, -y + 1, -z + 2).
	Fig. 2. The crystal packing of the title compound, viewed down the c axis showing dimer formation by R²₂(28) ring motif.

N,N'-Bis(2-hydroxy-3-ethoxybenzylidene)butane-1,4-diamine top

Crystal data top

C₂₂H₂₈N₂O₄	Z = 1
M_r = 384.46	F(000) = 206
Triclinic, P1	D_x = 1.294 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.8647 (2) Å	Cell parameters from 2475 reflections
b = 6.9052 (2) Å	θ = 2.5–29.4°
c = 10.8083 (3) Å	µ = 0.09 mm⁻¹
α = 92.779 (2)°	T = 100 K
β = 99.908 (2)°	Plate, yellow
γ = 101.239 (2)°	0.45 × 0.19 × 0.07 mm
V = 493.23 (2) Å³

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	2954 independent reflections
Radiation source: fine-focus sealed tube	2157 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.033
ϕ and ω scans	θ_max = 30.4°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −9→9
T_min = 0.961, T_max = 0.994	k = −9→9
8962 measured reflections	l = −14→15

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.131	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0681P)² + 0.047P] where P = (F_o² + 2F_c²)/3
2954 reflections	(Δ/σ)_max < 0.001
129 parameters	Δρ_max = 0.43 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₂₂H₂₈N₂O₄	γ = 101.239 (2)°
M_r = 384.46	V = 493.23 (2) Å³
Triclinic, P1	Z = 1
a = 6.8647 (2) Å	Mo Kα radiation
b = 6.9052 (2) Å	µ = 0.09 mm⁻¹
c = 10.8083 (3) Å	T = 100 K
α = 92.779 (2)°	0.45 × 0.19 × 0.07 mm
β = 99.908 (2)°

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	2954 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2157 reflections with I > 2σ(I)
T_min = 0.961, T_max = 0.994	R_int = 0.033
8962 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.131	H-atom parameters constrained
S = 1.04	Δρ_max = 0.43 e Å⁻³
2954 reflections	Δρ_min = −0.27 e Å⁻³
129 parameters

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.69496 (13)	0.51130 (12)	0.23213 (9)	0.0191 (2)
H1	0.5792	0.4902	0.1870	0.029*
O2	1.05734 (12)	0.52787 (12)	0.36073 (8)	0.0178 (2)
N1	0.35928 (15)	0.30726 (15)	0.10848 (10)	0.0181 (2)
C1	0.75200 (17)	0.33702 (16)	0.25124 (11)	0.0149 (2)
C2	0.94642 (17)	0.34181 (16)	0.32117 (11)	0.0157 (2)
C3	1.00920 (18)	0.16571 (17)	0.34438 (12)	0.0177 (2)
H3A	1.1398	0.1690	0.3921	0.021*
C4	0.88179 (18)	−0.01729 (17)	0.29812 (12)	0.0188 (3)
H4A	0.9259	−0.1372	0.3146	0.023*
C5	0.69162 (18)	−0.02237 (17)	0.22845 (12)	0.0178 (2)
H5A	0.6058	−0.1462	0.1964	0.021*
C6	0.62455 (17)	0.15406 (16)	0.20476 (11)	0.0157 (2)
C7	0.42169 (18)	0.14831 (17)	0.13323 (11)	0.0169 (2)
H7A	0.3346	0.0238	0.1046	0.020*
C8	0.15522 (17)	0.29668 (17)	0.03663 (12)	0.0185 (3)
H8A	0.0561	0.2041	0.0735	0.022*
H8B	0.1478	0.2459	−0.0517	0.022*
C9	0.10389 (17)	0.50109 (17)	0.03934 (11)	0.0170 (2)
H9A	0.2076	0.5946	0.0065	0.020*
H9B	0.1064	0.5488	0.1276	0.020*
C10	1.26442 (17)	0.54481 (17)	0.42136 (12)	0.0182 (3)
H10A	1.3370	0.4755	0.3676	0.022*
H10B	1.2713	0.4857	0.5032	0.022*
C11	1.35712 (19)	0.76329 (19)	0.44083 (13)	0.0227 (3)
H11A	1.5003	0.7823	0.4795	0.034*
H11B	1.2866	0.8291	0.4964	0.034*
H11C	1.3448	0.8205	0.3593	0.034*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0164 (4)	0.0136 (4)	0.0265 (5)	0.0048 (3)	−0.0003 (3)	0.0029 (3)
O2	0.0134 (4)	0.0146 (4)	0.0234 (5)	0.0009 (3)	0.0006 (3)	0.0005 (3)
N1	0.0145 (5)	0.0188 (5)	0.0215 (5)	0.0055 (4)	0.0021 (4)	0.0024 (4)
C1	0.0163 (6)	0.0129 (5)	0.0168 (6)	0.0040 (4)	0.0054 (4)	0.0031 (4)
C2	0.0154 (6)	0.0149 (5)	0.0172 (6)	0.0021 (4)	0.0051 (4)	0.0015 (4)
C3	0.0143 (6)	0.0190 (6)	0.0203 (6)	0.0050 (4)	0.0023 (5)	0.0029 (4)
C4	0.0194 (6)	0.0149 (5)	0.0237 (6)	0.0069 (4)	0.0044 (5)	0.0039 (4)
C5	0.0175 (6)	0.0133 (5)	0.0223 (6)	0.0030 (4)	0.0029 (5)	0.0015 (4)
C6	0.0142 (6)	0.0157 (5)	0.0176 (6)	0.0038 (4)	0.0033 (4)	0.0021 (4)
C7	0.0154 (6)	0.0154 (5)	0.0192 (6)	0.0019 (4)	0.0027 (5)	0.0011 (4)
C8	0.0137 (6)	0.0187 (6)	0.0221 (6)	0.0043 (4)	0.0001 (5)	0.0009 (5)
C9	0.0157 (6)	0.0176 (5)	0.0186 (6)	0.0055 (4)	0.0032 (5)	0.0025 (4)
C10	0.0128 (6)	0.0193 (6)	0.0221 (6)	0.0029 (4)	0.0030 (5)	0.0009 (4)
C11	0.0150 (6)	0.0219 (6)	0.0291 (7)	0.0006 (4)	0.0021 (5)	0.0027 (5)

Geometric parameters (Å, º) top

O1—C1	1.3507 (12)	C6—C7	1.4641 (15)
O1—H1	0.8400	C7—H7A	0.9500
O2—C2	1.3662 (13)	C8—C9	1.5201 (15)
O2—C10	1.4391 (13)	C8—H8A	0.9900
N1—C7	1.2776 (14)	C8—H8B	0.9900
N1—C8	1.4666 (14)	C9—C9ⁱ	1.527 (2)
C1—C6	1.4037 (16)	C9—H9A	0.9900
C1—C2	1.4096 (16)	C9—H9B	0.9900
C2—C3	1.3871 (15)	C10—C11	1.5081 (17)
C3—C4	1.4033 (17)	C10—H10A	0.9900
C3—H3A	0.9500	C10—H10B	0.9900
C4—C5	1.3833 (16)	C11—H11A	0.9800
C4—H4A	0.9500	C11—H11B	0.9800
C5—C6	1.4036 (15)	C11—H11C	0.9800
C5—H5A	0.9500

C1—O1—H1	109.5	N1—C8—C9	109.97 (10)
C2—O2—C10	117.43 (9)	N1—C8—H8A	109.7
C7—N1—C8	120.11 (11)	C9—C8—H8A	109.7
O1—C1—C6	122.32 (10)	N1—C8—H8B	109.7
O1—C1—C2	118.03 (10)	C9—C8—H8B	109.7
C6—C1—C2	119.65 (10)	H8A—C8—H8B	108.2
O2—C2—C3	125.83 (11)	C8—C9—C9ⁱ	111.80 (13)
O2—C2—C1	114.48 (9)	C8—C9—H9A	109.3
C3—C2—C1	119.70 (11)	C9ⁱ—C9—H9A	109.3
C2—C3—C4	120.70 (11)	C8—C9—H9B	109.3
C2—C3—H3A	119.7	C9ⁱ—C9—H9B	109.3
C4—C3—H3A	119.7	H9A—C9—H9B	107.9
C5—C4—C3	119.72 (11)	O2—C10—C11	106.44 (9)
C5—C4—H4A	120.1	O2—C10—H10A	110.4
C3—C4—H4A	120.1	C11—C10—H10A	110.4
C4—C5—C6	120.48 (11)	O2—C10—H10B	110.4
C4—C5—H5A	119.8	C11—C10—H10B	110.4
C6—C5—H5A	119.8	H10A—C10—H10B	108.6
C5—C6—C1	119.75 (10)	C10—C11—H11A	109.5
C5—C6—C7	120.42 (11)	C10—C11—H11B	109.5
C1—C6—C7	119.83 (10)	H11A—C11—H11B	109.5
N1—C7—C6	121.38 (11)	C10—C11—H11C	109.5
N1—C7—H7A	119.3	H11A—C11—H11C	109.5
C6—C7—H7A	119.3	H11B—C11—H11C	109.5

C10—O2—C2—C3	6.39 (17)	C4—C5—C6—C7	−178.73 (11)
C10—O2—C2—C1	−173.76 (10)	O1—C1—C6—C5	−179.51 (11)
O1—C1—C2—O2	−0.84 (16)	C2—C1—C6—C5	0.09 (17)
C6—C1—C2—O2	179.55 (10)	O1—C1—C6—C7	−0.25 (17)
O1—C1—C2—C3	179.02 (10)	C2—C1—C6—C7	179.35 (10)
C6—C1—C2—C3	−0.60 (17)	C8—N1—C7—C6	−179.99 (10)
O2—C2—C3—C4	−179.65 (11)	C5—C6—C7—N1	−178.57 (11)
C1—C2—C3—C4	0.51 (18)	C1—C6—C7—N1	2.18 (18)
C2—C3—C4—C5	0.10 (18)	C7—N1—C8—C9	170.13 (11)
C3—C4—C5—C6	−0.61 (18)	N1—C8—C9—C9ⁱ	177.44 (12)
C4—C5—C6—C1	0.51 (18)	C2—O2—C10—C11	173.37 (10)

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.84	1.82	2.5638 (14)	147
C5—H5A···O1ⁱⁱ	0.95	2.59	3.2268 (14)	125
C11—H11B···Cg1ⁱⁱⁱ	0.98	2.96	3.5403 (15)	145

Symmetry codes: (ii) x, y−1, z; (iii) −x+2, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₂₂H₂₈N₂O₄
M_r	384.46
Crystal system, space group	Triclinic, P1
Temperature (K)	100
a, b, c (Å)	6.8647 (2), 6.9052 (2), 10.8083 (3)
α, β, γ (°)	92.779 (2), 99.908 (2), 101.239 (2)
V (Å³)	493.23 (2)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.45 × 0.19 × 0.07

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.961, 0.994
No. of measured, independent and observed [I > 2σ(I)] reflections	8962, 2954, 2157
R_int	0.033
(sin θ/λ)_max (Å⁻¹)	0.712

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.131, 1.04
No. of reflections	2954
No. of parameters	129
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.43, −0.27

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.8400	1.8200	2.5638 (14)	147.00
C5—H5A···O1ⁱ	0.9500	2.5900	3.2268 (14)	125.00
C11—H11B···Cg1ⁱⁱ	0.9800	2.9600	3.5403 (15)	145.00

Symmetry codes: (i) x, y−1, z; (ii) −x+2, −y+1, −z+1.

Footnotes

‡Additional correspondence author: e-mail: zsrkk@yahoo.com.

Acknowledgements

HKF and RK thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant No. 305/PFIZIK/613312. RK thanks Universiti Sains Malaysia for the award of a post-doctoral research fellowship. HK and AJ thank PNU for financial support. HKF also thanks Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012.

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