5-Diethyl­amino-2-{(E)-[(3-iodo­phen­yl)imino]­meth­yl}phenol

Vesek, H.; Kazak, C.; Ağar, E.; Gümüş, S.

doi:10.1107/S1600536812022556

organic compounds

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ISSN: 2056-9890

Volume 68| Part 6| June 2012| Page o1963

doi:10.1107/S1600536812022556

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5-Diethylamino-2-{(E)-[(3-iodophenyl)imino]methyl}phenol

Hilal Vesek,^a ^* Canan Kazak,^a Erbil Ağar ^b and Sümeyye Gümüş ^b

^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, Kurupelit, TR-55139 Samsun, Turkey
^*Correspondence e-mail: hilal.vesek@oposta.omu.tr

(Received 11 April 2012; accepted 17 May 2012; online 31 May 2012)

The title Schiff base, C₁₇H₁₉IN₂O, is not planar, displaying a dihedral angle of 34.9 (2)° between the two aromatic rings. The molecular conformation allows the formation of a strong intramolecular O—H⋯N hydrogen bond with graph-set motif S(6) between the hydroxy group and the imine N atom.

Related literature

For Schiff base tautomerism, see: Cohen et al. (1964 ); Hadjoudis et al. (1987 ). For the biological properties of Schiff bases, see: Dao et al. (2000 ). For related structures, see: Gül, Ağar & Işık (2007 ); Gül, Erşahin, Ağar & Işık (2007 ); Pekdemir et al. (2012 ); Yüce et al. (2004 ); Demirtaş et al. (2011 ). For the classification of hydrogen-bonding patterns, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₇H₁₉IN₂O
M_r = 394.24
Orthorhombic, P 2₁ 2₁ 2₁
a = 6.6999 (6) Å
b = 15.248 (2) Å
c = 16.1195 (15) Å
V = 1646.7 (3) Å³
Z = 4
Mo Kα radiation
μ = 1.95 mm⁻¹
T = 296 K
0.49 × 0.34 × 0.21 mm

Data collection

Stoe IPDS II diffractometer
Absorption correction: integration (X-RED32; Stoe & Cie, 2002 ) T_min = 0.451, T_max = 0.603
6072 measured reflections
3225 independent reflections
2417 reflections with I > 2σ(I)
R_int = 0.049

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.074
S = 0.86
3225 reflections
190 parameters
H-atom parameters constrained
Δρ_max = 0.57 e Å⁻³
Δρ_min = −0.63 e Å⁻³
Absolute structure: Flack (1983 ), 1355 Friedel pairs
Flack parameter: −0.02 (3)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.82	1.85	2.577 (6)	147

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 (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812022556/bh2429sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812022556/bh2429Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812022556/bh2429Isup3.cml

checkCIF report

Comment top

Schiff base compounds are used in many different areas. Generally, they exhibit biological activity: anti-bacterial and anti-cancer properties were demonstrated (Dao et al., 2000). Thermochromic and photochromic Schiff base compounds can be classified on the basis of their specific characteristics (Cohen et al., 1964): intermolecular hydrogen bonds may be formed in two different ways. Chromic action is strongly related to the tautomerization between the O—H···N═C—C═C (enolimino) and —C═ O···H—N—C═C—C (ketoamino) tautomeric forms (Hadjoudis et al., 1987). The title compound is stabilized in the phenol-imine tautomeric form (Fig. 1).

The C1—N1 bond length, 1.407 (7) Å, is in agreement with the distance reported for 2-[(E)-(naphthalen-2-ylimino)methyl]-4-(trifluoromethoxy)phenol [1.417 (2) Å, Pekdemir et al., 2012] and 1-{4-[(2-hydroxybenzylidene)amino]phenyl}ethanone [1.4138 (17) Å, Yüce et al., 2004]. The C7═N1 bond length of 1.292 (7) Å is also comparable to the imine double bond found in (E)-4-bromo-2-[(2-hydroxy-5-methylphenyl)iminomethy]phenol [1.289 (6) Å, Gül, Ağar & Işık, 2007]. Figure 1 also shows a strong intramolecular hydrogen bond O1—H1···N1, which can be described as an S(6) motif (Bernstein et al., 1995). The O1···N1 separation of 2.577 (6) Å is comparable to that observed for similar hydrogen bonds in related Schiff bases (Gül, Erşahin, Ağar & Işık, 2007). The C3—I1 bond length, 2.114 (5) Å, is in agreement with other C—I bonds, for example in 2-(2-iodophenyl)isoindoline-1,3-dione [2.094 (3) Å; Demirtaş et al., 2011]. The title molecule is not planar, displaying a dihedral angle of 34.9 (2)° between the two aromatic rings.

Related literature top

For Schiff base tautomerism, see: Cohen et al. (1964); Hadjoudis et al. (1987). For the biological properties of Schiff bases, see: Dao et al. (2000). For related structures, see: Gül, Ağar & Işık (2007); Gül, Erşahin, Ağar & Işık (2007); Pekdemir et al. (2012); Yüce et al. (2004); Demirtaş et al. (2011). For the classification of hydrogen-bonding patterns, see: Bernstein et al. (1995).

Experimental top

The title compound was prepared by refluxing for 1 h. a mixture of 4-(diethylamino)-2-hydroxybenzaldehyde (0.022 g, 0.11 mmol) in ethanol (20 ml) and 3-iodoaniline (0.025 g, 0.11 mmol) in ethanol (20 ml). Crystals suitable for X-ray analysis were obtained from ethanol by slow evaporation (yield: 72%, m.p. 394–395 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 (Spek, 2009).

Figures top

Fig. 1. The molecular structure of the title compound, showing displacement ellipsoids at the 30% probability level.

5-Diethylamino-2-{(E)-[(3-iodophenyl)imino]methyl}phenol top

Crystal data top

C₁₇H₁₉IN₂O	D_x = 1.590 Mg m⁻³
M_r = 394.24	Melting point: 394 K
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 8061 reflections
a = 6.6999 (6) Å	θ = 1.8–28.1°
b = 15.248 (2) Å	µ = 1.95 mm⁻¹
c = 16.1195 (15) Å	T = 296 K
V = 1646.7 (3) Å³	Prism, yellow
Z = 4	0.49 × 0.34 × 0.21 mm
F(000) = 784

Data collection top

Stoe IPDS II diffractometer	3225 independent reflections
Radiation source: fine-focus sealed tube	2417 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.049
Detector resolution: 6.67 pixels mm^-1	θ_max = 26.0°, θ_min = 1.8°
rotation method scans	h = −6→8
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	k = −15→19
T_min = 0.451, T_max = 0.603	l = −20→20
6072 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.074	w = 1/[σ²(F_o²) + (0.0337P)²] where P = (F_o² + 2F_c²)/3
S = 0.86	(Δ/σ)_max = 0.002
3225 reflections	Δρ_max = 0.57 e Å⁻³
190 parameters	Δρ_min = −0.63 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 1355 Friedel pairs
0 constraints	Absolute structure parameter: −0.02 (3)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₁₇H₁₉IN₂O	V = 1646.7 (3) Å³
M_r = 394.24	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 6.6999 (6) Å	µ = 1.95 mm⁻¹
b = 15.248 (2) Å	T = 296 K
c = 16.1195 (15) Å	0.49 × 0.34 × 0.21 mm

Data collection top

Stoe IPDS II diffractometer	3225 independent reflections
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	2417 reflections with I > 2σ(I)
T_min = 0.451, T_max = 0.603	R_int = 0.049
6072 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.074	Δρ_max = 0.57 e Å⁻³
S = 0.86	Δρ_min = −0.63 e Å⁻³
3225 reflections	Absolute structure: Flack (1983), 1355 Friedel pairs
190 parameters	Absolute structure parameter: −0.02 (3)
0 restraints

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

	x	y	z	U_iso*/U_eq
C1	0.5355 (9)	0.7994 (3)	0.3130 (3)	0.0424 (14)
C2	0.6547 (9)	0.8639 (3)	0.2779 (3)	0.0438 (13)
H2	0.7869	0.8699	0.2946	0.053*
C3	0.5784 (8)	0.9186 (3)	0.2188 (3)	0.0411 (13)
C4	0.3846 (10)	0.9108 (4)	0.1905 (4)	0.0539 (16)
H4	0.3353	0.9477	0.1494	0.065*
C5	0.2675 (12)	0.8468 (4)	0.2254 (4)	0.0648 (16)
H5	0.1361	0.8409	0.2077	0.078*
C6	0.3395 (9)	0.7908 (4)	0.2860 (4)	0.0513 (15)
H6	0.2573	0.7478	0.3085	0.062*
C7	0.5263 (10)	0.7053 (4)	0.4284 (3)	0.0463 (16)
H7	0.3934	0.7205	0.4366	0.056*
C8	0.6183 (8)	0.6397 (4)	0.4808 (4)	0.0398 (14)
C9	0.5079 (9)	0.5976 (4)	0.5432 (4)	0.0470 (14)
H9	0.3765	0.6148	0.5522	0.056*
C10	0.5856 (9)	0.5330 (4)	0.5909 (3)	0.0474 (15)
H10	0.5071	0.5067	0.6314	0.057*
C11	0.7872 (8)	0.5048 (3)	0.5794 (3)	0.0396 (12)
C12	0.8970 (8)	0.5476 (4)	0.5182 (3)	0.0429 (13)
H12	1.0285	0.5305	0.5091	0.052*
C13	0.8187 (8)	0.6140 (4)	0.4706 (3)	0.0382 (14)
C14	1.0628 (11)	0.4029 (4)	0.6072 (4)	0.0602 (17)
H14A	1.1138	0.3722	0.6555	0.072*
H14B	1.1530	0.4512	0.5956	0.072*
C15	1.0651 (14)	0.3412 (6)	0.5345 (5)	0.098 (3)
H15A	1.1984	0.3200	0.5259	0.147*
H15B	1.0204	0.3715	0.4858	0.147*
H15C	0.9779	0.2926	0.5455	0.147*
C16	0.7536 (12)	0.3977 (4)	0.6930 (3)	0.0594 (15)
H16A	0.6713	0.4420	0.7194	0.071*
H16B	0.8452	0.3752	0.7345	0.071*
C17	0.6208 (11)	0.3235 (5)	0.6640 (6)	0.085 (2)
H17A	0.5497	0.2997	0.7105	0.127*
H17B	0.7012	0.2785	0.6392	0.127*
H17C	0.5273	0.3454	0.6239	0.127*
I1	0.76828 (6)	1.01529 (2)	0.16772 (2)	0.05438 (13)
N1	0.6279 (7)	0.7428 (3)	0.3703 (3)	0.0431 (11)
N2	0.8680 (7)	0.4386 (3)	0.6273 (3)	0.0478 (12)
O1	0.9360 (6)	0.6522 (3)	0.4129 (2)	0.0532 (11)
H1	0.8727	0.6905	0.3888	0.080*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.056 (3)	0.032 (3)	0.039 (3)	0.004 (3)	0.001 (2)	−0.006 (2)
C2	0.048 (3)	0.044 (3)	0.039 (3)	0.000 (3)	0.000 (2)	0.002 (2)
C3	0.042 (3)	0.037 (3)	0.044 (3)	0.002 (2)	0.011 (2)	0.004 (2)
C4	0.061 (4)	0.049 (4)	0.051 (4)	0.000 (3)	−0.017 (3)	0.008 (3)
C5	0.049 (4)	0.062 (3)	0.084 (4)	−0.002 (4)	−0.015 (4)	0.008 (3)
C6	0.051 (4)	0.041 (3)	0.061 (4)	−0.006 (3)	−0.008 (3)	0.005 (3)
C7	0.055 (4)	0.043 (4)	0.040 (3)	0.008 (3)	0.006 (3)	−0.008 (3)
C8	0.047 (3)	0.032 (3)	0.040 (3)	−0.003 (3)	0.007 (3)	−0.001 (3)
C9	0.043 (3)	0.047 (4)	0.051 (4)	−0.003 (3)	0.011 (3)	0.003 (3)
C10	0.046 (3)	0.051 (4)	0.045 (3)	0.000 (3)	0.009 (2)	0.004 (3)
C11	0.041 (3)	0.036 (3)	0.041 (2)	0.000 (3)	−0.002 (2)	−0.0006 (17)
C12	0.040 (3)	0.042 (3)	0.046 (3)	0.001 (2)	0.008 (3)	−0.002 (3)
C13	0.046 (4)	0.032 (3)	0.037 (3)	−0.006 (2)	0.007 (2)	−0.002 (2)
C14	0.063 (4)	0.056 (4)	0.061 (4)	0.010 (3)	−0.007 (3)	0.013 (3)
C15	0.108 (7)	0.089 (6)	0.098 (7)	0.025 (5)	0.021 (5)	−0.012 (5)
C16	0.064 (4)	0.061 (3)	0.054 (3)	−0.001 (5)	0.002 (4)	0.018 (2)
C17	0.072 (5)	0.069 (5)	0.114 (6)	−0.019 (4)	0.003 (5)	0.024 (5)
I1	0.0585 (2)	0.05387 (18)	0.05074 (17)	−0.0006 (2)	0.0024 (2)	0.01511 (17)
N1	0.054 (3)	0.036 (2)	0.039 (2)	−0.001 (2)	0.004 (2)	0.003 (2)
N2	0.050 (3)	0.052 (3)	0.041 (2)	0.003 (2)	0.005 (2)	0.011 (2)
O1	0.051 (3)	0.060 (3)	0.048 (3)	0.008 (2)	0.015 (2)	0.013 (2)

Geometric parameters (Å, º) top

C1—C2	1.388 (7)	C11—N2	1.381 (7)
C1—C6	1.390 (8)	C11—C12	1.393 (7)
C1—N1	1.407 (7)	C12—C13	1.374 (7)
C2—C3	1.365 (7)	C12—H12	0.9300
C2—H2	0.9300	C13—O1	1.349 (6)
C3—C4	1.381 (8)	C14—N2	1.450 (8)
C3—I1	2.114 (5)	C14—C15	1.503 (10)
C4—C5	1.373 (8)	C14—H14A	0.9700
C4—H4	0.9300	C14—H14B	0.9700
C5—C6	1.384 (8)	C15—H15A	0.9600
C5—H5	0.9300	C15—H15B	0.9600
C6—H6	0.9300	C15—H15C	0.9600
C7—N1	1.292 (7)	C16—N2	1.449 (7)
C7—C8	1.446 (8)	C16—C17	1.512 (9)
C7—H7	0.9300	C16—H16A	0.9700
C8—C9	1.404 (8)	C16—H16B	0.9700
C8—C13	1.409 (8)	C17—H17A	0.9600
C9—C10	1.354 (8)	C17—H17B	0.9600
C9—H9	0.9300	C17—H17C	0.9600
C10—C11	1.430 (9)	O1—H1	0.8200
C10—H10	0.9300

C2—C1—C6	118.8 (5)	C13—C12—H12	118.7
C2—C1—N1	116.7 (5)	C11—C12—H12	118.7
C6—C1—N1	124.3 (5)	O1—C13—C12	118.7 (5)
C3—C2—C1	120.1 (5)	O1—C13—C8	121.0 (6)
C3—C2—H2	119.9	C12—C13—C8	120.2 (5)
C1—C2—H2	119.9	N2—C14—C15	114.7 (6)
C2—C3—C4	122.0 (5)	N2—C14—H14A	108.6
C2—C3—I1	118.2 (4)	C15—C14—H14A	108.6
C4—C3—I1	119.8 (4)	N2—C14—H14B	108.6
C5—C4—C3	117.6 (5)	C15—C14—H14B	108.6
C5—C4—H4	121.2	H14A—C14—H14B	107.6
C3—C4—H4	121.2	C14—C15—H15A	109.5
C4—C5—C6	121.9 (6)	C14—C15—H15B	109.5
C4—C5—H5	119.0	H15A—C15—H15B	109.5
C6—C5—H5	119.0	C14—C15—H15C	109.5
C5—C6—C1	119.5 (6)	H15A—C15—H15C	109.5
C5—C6—H6	120.3	H15B—C15—H15C	109.5
C1—C6—H6	120.3	N2—C16—C17	114.0 (5)
N1—C7—C8	120.3 (6)	N2—C16—H16A	108.8
N1—C7—H7	119.8	C17—C16—H16A	108.8
C8—C7—H7	119.8	N2—C16—H16B	108.8
C9—C8—C13	117.3 (6)	C17—C16—H16B	108.8
C9—C8—C7	120.6 (5)	H16A—C16—H16B	107.6
C13—C8—C7	122.0 (6)	C16—C17—H17A	109.5
C10—C9—C8	122.5 (6)	C16—C17—H17B	109.5
C10—C9—H9	118.8	H17A—C17—H17B	109.5
C8—C9—H9	118.8	C16—C17—H17C	109.5
C9—C10—C11	120.6 (5)	H17A—C17—H17C	109.5
C9—C10—H10	119.7	H17B—C17—H17C	109.5
C11—C10—H10	119.7	C7—N1—C1	121.0 (5)
N2—C11—C12	122.1 (5)	C11—N2—C16	121.0 (5)
N2—C11—C10	121.2 (4)	C11—N2—C14	120.2 (5)
C12—C11—C10	116.7 (5)	C16—N2—C14	118.6 (5)
C13—C12—C11	122.6 (5)	C13—O1—H1	109.5

C6—C1—C2—C3	1.1 (8)	C10—C11—C12—C13	0.2 (8)
N1—C1—C2—C3	176.8 (5)	C11—C12—C13—O1	179.6 (5)
C1—C2—C3—C4	−1.7 (8)	C11—C12—C13—C8	−1.9 (9)
C1—C2—C3—I1	−179.9 (4)	C9—C8—C13—O1	−178.9 (5)
C2—C3—C4—C5	1.5 (9)	C7—C8—C13—O1	2.5 (8)
I1—C3—C4—C5	179.7 (4)	C9—C8—C13—C12	2.7 (8)
C3—C4—C5—C6	−0.8 (9)	C7—C8—C13—C12	−175.9 (5)
C4—C5—C6—C1	0.3 (9)	C8—C7—N1—C1	172.9 (5)
C2—C1—C6—C5	−0.4 (8)	C2—C1—N1—C7	152.9 (5)
N1—C1—C6—C5	−175.8 (5)	C6—C1—N1—C7	−31.6 (8)
N1—C7—C8—C9	−179.0 (6)	C12—C11—N2—C16	177.3 (5)
N1—C7—C8—C13	−0.4 (9)	C10—C11—N2—C16	−2.5 (8)
C13—C8—C9—C10	−1.9 (9)	C12—C11—N2—C14	−8.6 (8)
C7—C8—C9—C10	176.7 (6)	C10—C11—N2—C14	171.6 (5)
C8—C9—C10—C11	0.3 (9)	C17—C16—N2—C11	85.1 (7)
C9—C10—C11—N2	−179.6 (5)	C17—C16—N2—C14	−89.0 (7)
C9—C10—C11—C12	0.6 (7)	C15—C14—N2—C11	−76.5 (8)
N2—C11—C12—C13	−179.5 (5)	C15—C14—N2—C16	97.7 (7)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.85	2.577 (6)	147

Experimental details

Crystal data
Chemical formula	C₁₇H₁₉IN₂O
M_r	394.24
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	296
a, b, c (Å)	6.6999 (6), 15.248 (2), 16.1195 (15)
V (Å³)	1646.7 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.95
Crystal size (mm)	0.49 × 0.34 × 0.21

Data collection
Diffractometer	Stoe IPDS II diffractometer
Absorption correction	Integration (X-RED32; Stoe & Cie, 2002)
T_min, T_max	0.451, 0.603
No. of measured, independent and observed [I > 2σ(I)] reflections	6072, 3225, 2417
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.074, 0.86
No. of reflections	3225
No. of parameters	190
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.57, −0.63
Absolute structure	Flack (1983), 1355 Friedel pairs
Absolute structure parameter	−0.02 (3)

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 (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.85	2.577 (6)	147.4

Acknowledgements

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

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