2-[(4-Ethyl­phen­yl)imino­meth­yl]-3,5-dimethoxy­phenol

Şahin, Z.S.; Erşahin, F.; Ağar, A.A.; Işık, Ş.

doi:10.1107/S1600536809004784

organic compounds

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ISSN: 2056-9890

Volume 65| Part 3| March 2009| Page o547

doi:10.1107/S1600536809004784

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2-[(4-Ethylphenyl)iminomethyl]-3,5-dimethoxyphenol

Zarife Sibel Şahin,^a Ferda Erşahin,^b Ayşen Alaman Ağar ^b and Şamil Işık ^a ^*

^aDepartment of Physics, Faculty of Arts and Sciences, Ondokuz Mayıs University, Kurupelit, TR-55139 Samsun, Turkey, and ^bDepartment of Chemistry, Faculty of Arts and Sciences, Ondokuz Mayıs University, 55139 Samsun, Turkey
^*Correspondence e-mail: sgul@omu.edu.tr

(Received 19 January 2009; accepted 10 February 2009; online 18 February 2009)

The title compound, C₁₇H₁₉NO₃, adopts the phenol–imine tautomeric form, with a resonance-assisted O—H⋯N intramolecular hydrogen bond [O⋯N = 2.551 (3) Å]. The dihedral angle between the two benzene rings is 45.42 (7)°. The two methoxy groups are coplanar with the attached benzene ring [C—O—C—C torsion angles = −1.1 (5) and 3.2 (4)°].

Related literature

For the photochromic and thermochromic characteristics of Schiff base compounds, see: Hadjoudis et al. (1987 ); Lozier et al. (1975 ). For the notation of hydrogen-bonding motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₇H₁₉NO₃
M_r = 285.33
Orthorhombic, P 2₁ 2₁ 2₁
a = 7.5026 (5) Å
b = 9.4540 (8) Å
c = 21.4408 (13) Å
V = 1520.79 (19) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 296 K
0.46 × 0.35 × 0.11 mm

Data collection

Stoe IPDS II diffractometer
Absorption correction: integration (X-RED32; Stoe & Cie, 2002 ) T_min = 0.991, T_max = 0.998
10094 measured reflections
1831 independent reflections
1036 reflections with I > 2σ(I)
R_int = 0.049

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.077
S = 0.92
1831 reflections
191 parameters
H-atom parameters constrained
Δρ_max = 0.09 e Å⁻³
Δρ_min = −0.11 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯N1	0.82	1.82	2.551 (3)	149

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809004784/ci2762sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809004784/ci2762Isup2.hkl

checkCIF report

Comment top

Most Schiff base compounds have antibacterial, anticancer, anti-inflammatory and antioxic properties. In addition Schiff bases are important in diverse fields of chemistry and biochemistry owing to their biological activites (Lozier et al., 1975). There are two types of intramolecular hydrogen bonds in Schiff bases which may stabilize them in keto–amine (N—H···O hydrogen bond) or phenol–imine (N···H—O hydrogen bond) tautomeric forms (Hadjoudis et al., 1987). Our investigations show that the title compound adopts the phenol–imine tautomeric form (Fig. 1).

The N1—C7 bond length of 1.281 (3) Å is typical of a double bond. The dihedral angle between the C1–C6 and C8–C13 benzene rings is 45.4 (2)°. The C4—C7—N1—C8 torsion angle is -179.5 (3)°. The strong intramolecular O3—H3···N1 hydrogen bond forms an S(6) motif (Bernstein et al., 1995).

Related literature top

For the photochromic and thermochromic characteristics of Schiff base compounds, see: Hadjoudis et al. (1987); Lozier et al. (1975). For the notation of hydrogen-bonding motifs, see: Bernstein et al. (1995).

Experimental top

2-Hydroxy-4,6-dimethoxybenzaldehyde (0.0327 g, 0.18 mmol) in ethanol (20 ml) was added to a solution of 4-ethylaniline (0.0219 g, 0.18 mmol) in ethanol (20 ml) and the reaction mixture was stirred for 1 h under reflux, to obtain the title compound. Single crystals suitable for X-ray analysis were obtained by slow evaporation of an ethanol solution (yield 61%; m.p.351–353 K).

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

Fig. 1. The molecular structure of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability.

2-[(4-Ethylphenyl)iminomethyl]-3,5-dimethoxyphenol top

Crystal data top

C₁₇H₁₉NO₃	F(000) = 608
M_r = 285.33	D_x = 1.246 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 10094 reflections
a = 7.5026 (5) Å	θ = 1.9–27.7°
b = 9.4540 (8) Å	µ = 0.09 mm⁻¹
c = 21.4408 (13) Å	T = 296 K
V = 1520.79 (19) Å³	Prism, yellow
Z = 4	0.46 × 0.35 × 0.11 mm

Data collection top

Stoe IPDS II diffractometer	1831 independent reflections
Radiation source: fine-focus sealed tube	1036 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.049
Detector resolution: 6.67 pixels mm^-1	θ_max = 26.5°, θ_min = 1.9°
ω scans	h = −9→8
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	k = −11→10
T_min = 0.991, T_max = 0.998	l = −26→26
10094 measured reflections

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.077	H-atom parameters constrained
S = 0.92	w = 1/[σ²(F_o²) + (0.0332P)²] where P = (F_o² + 2F_c²)/3
1831 reflections	(Δ/σ)_max = 0.001
191 parameters	Δρ_max = 0.09 e Å⁻³
0 restraints	Δρ_min = −0.11 e Å⁻³

Crystal data top

C₁₇H₁₉NO₃	V = 1520.79 (19) Å³
M_r = 285.33	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 7.5026 (5) Å	µ = 0.09 mm⁻¹
b = 9.4540 (8) Å	T = 296 K
c = 21.4408 (13) Å	0.46 × 0.35 × 0.11 mm

Data collection top

Stoe IPDS II diffractometer	1831 independent reflections
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	1036 reflections with I > 2σ(I)
T_min = 0.991, T_max = 0.998	R_int = 0.049
10094 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	0 restraints
wR(F²) = 0.077	H-atom parameters constrained
S = 0.92	Δρ_max = 0.09 e Å⁻³
1831 reflections	Δρ_min = −0.11 e Å⁻³
191 parameters

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.

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 > σ(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
C1	0.2906 (4)	0.3417 (3)	0.70797 (12)	0.0630 (8)
C2	0.2290 (5)	0.3445 (3)	0.76807 (12)	0.0692 (9)
H2	0.1988	0.4295	0.7871	0.083*
C3	0.2128 (4)	0.2174 (3)	0.79972 (12)	0.0635 (8)
C4	0.2526 (4)	0.0871 (3)	0.77182 (11)	0.0566 (7)
C5	0.3141 (4)	0.0911 (3)	0.70914 (12)	0.0610 (8)
C6	0.3354 (4)	0.2165 (3)	0.67808 (12)	0.0630 (8)
H6	0.3794	0.2178	0.6375	0.076*
C7	0.2409 (4)	−0.0436 (3)	0.80628 (12)	0.0601 (7)
H7	0.2663	−0.1284	0.7862	0.072*
C8	0.1874 (4)	−0.1759 (3)	0.89708 (11)	0.0559 (7)
C9	0.2513 (4)	−0.1775 (3)	0.95769 (12)	0.0679 (8)
H9	0.2991	−0.0956	0.9749	0.081*
C10	0.2447 (5)	−0.3000 (3)	0.99269 (12)	0.0699 (8)
H10	0.2930	−0.3004	1.0326	0.084*
C11	0.1679 (4)	−0.4216 (3)	0.96967 (12)	0.0625 (8)
C12	0.1013 (4)	−0.4181 (3)	0.90983 (12)	0.0634 (8)
H12	0.0481	−0.4988	0.8934	0.076*
C13	0.1118 (4)	−0.2971 (3)	0.87352 (11)	0.0604 (8)
H13	0.0675	−0.2980	0.8330	0.072*
C14	0.2705 (5)	0.5932 (3)	0.69842 (14)	0.0878 (10)
H14A	0.2939	0.6663	0.6685	0.132*
H14B	0.3412	0.6091	0.7350	0.132*
H14C	0.1464	0.5944	0.7094	0.132*
C15	0.4190 (5)	−0.0439 (4)	0.62229 (12)	0.0884 (11)
H15A	0.4361	−0.1407	0.6102	0.133*
H15B	0.5311	0.0049	0.6212	0.133*
H15C	0.3372	0.0007	0.5940	0.133*
C16	0.1567 (5)	−0.5544 (3)	1.00901 (14)	0.0857 (10)
H16A	0.1075	−0.5299	1.0494	0.103*
H16B	0.0747	−0.6198	0.9892	0.103*
C17	0.3298 (6)	−0.6273 (4)	1.01865 (17)	0.1268 (16)
H17A	0.3789	−0.6538	0.9790	0.190*
H17B	0.3116	−0.7105	1.0435	0.190*
H17C	0.4108	−0.5648	1.0397	0.190*
N1	0.1964 (3)	−0.0451 (2)	0.86397 (10)	0.0629 (7)
O1	0.3148 (3)	0.4591 (2)	0.67216 (8)	0.0834 (7)
O2	0.3479 (3)	−0.0388 (2)	0.68417 (8)	0.0781 (6)
O3	0.1587 (4)	0.2229 (2)	0.85970 (8)	0.0879 (7)
H3	0.1526	0.1425	0.8738	0.132*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.063 (2)	0.060 (2)	0.0665 (18)	−0.0127 (18)	−0.0040 (17)	0.0093 (15)
C2	0.082 (2)	0.0589 (19)	0.0672 (18)	−0.0111 (18)	0.0035 (17)	−0.0034 (15)
C3	0.070 (2)	0.0659 (18)	0.0548 (15)	−0.0106 (19)	0.0023 (15)	−0.0011 (15)
C4	0.0569 (19)	0.0566 (18)	0.0563 (15)	−0.0072 (17)	−0.0013 (14)	0.0015 (14)
C5	0.059 (2)	0.0607 (19)	0.0630 (17)	0.0015 (17)	−0.0005 (14)	−0.0030 (15)
C6	0.062 (2)	0.0680 (19)	0.0586 (15)	−0.0035 (19)	0.0001 (14)	0.0062 (16)
C7	0.0531 (18)	0.0607 (18)	0.0665 (17)	0.0020 (17)	0.0004 (15)	0.0003 (14)
C8	0.0524 (19)	0.062 (2)	0.0534 (15)	0.0002 (17)	0.0044 (14)	0.0009 (14)
C9	0.074 (2)	0.067 (2)	0.0621 (16)	−0.0129 (18)	−0.0080 (16)	−0.0051 (15)
C10	0.075 (2)	0.078 (2)	0.0569 (15)	−0.0050 (19)	−0.0071 (15)	0.0078 (16)
C11	0.061 (2)	0.062 (2)	0.0642 (17)	0.0031 (18)	0.0066 (14)	0.0035 (15)
C12	0.067 (2)	0.0563 (19)	0.0664 (18)	−0.0047 (17)	0.0065 (16)	−0.0045 (15)
C13	0.059 (2)	0.068 (2)	0.0541 (15)	−0.0018 (17)	0.0005 (14)	−0.0004 (16)
C14	0.104 (3)	0.062 (2)	0.097 (2)	−0.006 (2)	−0.009 (2)	0.0148 (18)
C15	0.110 (3)	0.092 (2)	0.0636 (18)	0.001 (2)	0.0264 (18)	−0.0078 (17)
C16	0.100 (3)	0.076 (2)	0.081 (2)	0.003 (2)	0.0076 (19)	0.0194 (18)
C17	0.125 (4)	0.119 (3)	0.137 (3)	0.047 (3)	0.038 (3)	0.058 (3)
N1	0.0689 (18)	0.0643 (15)	0.0554 (14)	−0.0059 (15)	0.0017 (12)	0.0050 (11)
O1	0.1059 (19)	0.0655 (13)	0.0788 (14)	−0.0060 (14)	0.0029 (12)	0.0146 (12)
O2	0.0968 (17)	0.0701 (14)	0.0674 (12)	0.0057 (13)	0.0197 (12)	0.0004 (11)
O3	0.136 (2)	0.0651 (13)	0.0621 (11)	−0.0094 (16)	0.0212 (12)	−0.0037 (9)

Geometric parameters (Å, º) top

C1—O1	1.362 (3)	C11—C12	1.377 (3)
C1—C2	1.369 (3)	C11—C16	1.515 (4)
C1—C6	1.387 (4)	C12—C13	1.386 (4)
C2—C3	1.385 (4)	C12—H12	0.93
C2—H2	0.93	C13—H13	0.93
C3—O3	1.350 (3)	C14—O1	1.426 (3)
C3—C4	1.401 (3)	C14—H14A	0.96
C4—C5	1.421 (3)	C14—H14B	0.96
C4—C7	1.442 (3)	C14—H14C	0.96
C5—O2	1.364 (3)	C15—O2	1.430 (3)
C5—C6	1.370 (4)	C15—H15A	0.96
C6—H6	0.93	C15—H15B	0.96
C7—N1	1.281 (3)	C15—H15C	0.96
C7—H7	0.93	C16—C17	1.485 (5)
C8—C13	1.375 (4)	C16—H16A	0.97
C8—C9	1.385 (3)	C16—H16B	0.97
C8—N1	1.428 (3)	C17—H17A	0.96
C9—C10	1.381 (4)	C17—H17B	0.96
C9—H9	0.93	C17—H17C	0.96
C10—C11	1.377 (4)	O3—H3	0.82
C10—H10	0.93

O1—C1—C2	124.0 (3)	C11—C12—H12	119.2
O1—C1—C6	113.7 (2)	C13—C12—H12	119.2
C2—C1—C6	122.2 (3)	C8—C13—C12	120.3 (2)
C1—C2—C3	118.3 (3)	C8—C13—H13	119.8
C1—C2—H2	120.9	C12—C13—H13	119.8
C3—C2—H2	120.9	O1—C14—H14A	109.5
O3—C3—C2	117.4 (3)	O1—C14—H14B	109.5
O3—C3—C4	120.3 (3)	H14A—C14—H14B	109.5
C2—C3—C4	122.3 (2)	O1—C14—H14C	109.5
C3—C4—C5	116.7 (3)	H14A—C14—H14C	109.5
C3—C4—C7	121.4 (2)	H14B—C14—H14C	109.5
C5—C4—C7	121.8 (3)	O2—C15—H15A	109.5
O2—C5—C6	124.5 (2)	O2—C15—H15B	109.5
O2—C5—C4	114.1 (2)	H15A—C15—H15B	109.5
C6—C5—C4	121.4 (3)	O2—C15—H15C	109.5
C5—C6—C1	119.0 (3)	H15A—C15—H15C	109.5
C5—C6—H6	120.5	H15B—C15—H15C	109.5
C1—C6—H6	120.5	C17—C16—C11	114.4 (3)
N1—C7—C4	121.3 (3)	C17—C16—H16A	108.7
N1—C7—H7	119.3	C11—C16—H16A	108.7
C4—C7—H7	119.3	C17—C16—H16B	108.7
C13—C8—C9	118.6 (3)	C11—C16—H16B	108.7
C13—C8—N1	124.0 (2)	H16A—C16—H16B	107.6
C9—C8—N1	117.3 (3)	C16—C17—H17A	109.5
C10—C9—C8	120.4 (3)	C16—C17—H17B	109.5
C10—C9—H9	119.8	H17A—C17—H17B	109.5
C8—C9—H9	119.8	C16—C17—H17C	109.5
C11—C10—C9	121.4 (3)	H17A—C17—H17C	109.5
C11—C10—H10	119.3	H17B—C17—H17C	109.5
C9—C10—H10	119.3	C7—N1—C8	120.1 (2)
C10—C11—C12	117.8 (3)	C1—O1—C14	118.1 (2)
C10—C11—C16	121.0 (3)	C5—O2—C15	117.6 (2)
C12—C11—C16	121.2 (3)	C3—O3—H3	109.5
C11—C12—C13	121.5 (3)

O1—C1—C2—C3	−179.1 (3)	N1—C8—C9—C10	179.2 (3)
C6—C1—C2—C3	0.5 (5)	C8—C9—C10—C11	−2.9 (5)
C1—C2—C3—O3	177.4 (3)	C9—C10—C11—C12	1.5 (5)
C1—C2—C3—C4	−1.8 (5)	C9—C10—C11—C16	−178.3 (3)
O3—C3—C4—C5	−178.1 (3)	C10—C11—C12—C13	0.4 (4)
C2—C3—C4—C5	1.1 (4)	C16—C11—C12—C13	−179.7 (3)
O3—C3—C4—C7	−1.4 (4)	C9—C8—C13—C12	−0.4 (4)
C2—C3—C4—C7	177.8 (3)	N1—C8—C13—C12	−177.1 (3)
C3—C4—C5—O2	−179.0 (3)	C11—C12—C13—C8	−1.0 (4)
C7—C4—C5—O2	4.3 (4)	C10—C11—C16—C17	−71.9 (4)
C3—C4—C5—C6	0.8 (4)	C12—C11—C16—C17	108.2 (4)
C7—C4—C5—C6	−175.8 (3)	C4—C7—N1—C8	−179.5 (3)
O2—C5—C6—C1	177.8 (3)	C13—C8—N1—C7	−43.7 (4)
C4—C5—C6—C1	−2.1 (4)	C9—C8—N1—C7	139.6 (3)
O1—C1—C6—C5	−179.0 (3)	C2—C1—O1—C14	−1.1 (5)
C2—C1—C6—C5	1.4 (5)	C6—C1—O1—C14	179.3 (3)
C3—C4—C7—N1	−1.1 (4)	C6—C5—O2—C15	3.2 (4)
C5—C4—C7—N1	175.4 (3)	C4—C5—O2—C15	−176.9 (3)
C13—C8—C9—C10	2.3 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···N1	0.82	1.82	2.551 (3)	149

Experimental details

Crystal data
Chemical formula	C₁₇H₁₉NO₃
M_r	285.33
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	296
a, b, c (Å)	7.5026 (5), 9.4540 (8), 21.4408 (13)
V (Å³)	1520.79 (19)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.46 × 0.35 × 0.11

Data collection
Diffractometer	Stoe IPDS II diffractometer
Absorption correction	Integration (X-RED32; Stoe & Cie, 2002)
T_min, T_max	0.991, 0.998
No. of measured, independent and observed [I > 2σ(I)] reflections	10094, 1831, 1036
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.628

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.077, 0.92
No. of reflections	1831
No. of parameters	191
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.09, −0.11

Computer programs: X-AREA (Stoe & Cie, 2002), X-RED32 (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···N1	0.82	1.82	2.551 (3)	149

Acknowledgements

The authors acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDS II diffractometer (purchased under grant No. F279 of the University Research Fund).

References

Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Hadjoudis, E., Vitterakis, M., Moustakali, I. & Mavridis, I. (1987). Tetrahedron, 43, 1345–1360. CrossRef CAS Web of Science Google Scholar
Lozier, R., Bogomolni, R. A. & Stoekenius, W. (1975). Biophys. J. 15, 955–962. CrossRef PubMed CAS Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Stoe & Cie (2002). X-RED and X-AREA. Stoe & Cie, Darmstadt, Germany. Google Scholar