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Acta Crystallogr Sect E Struct Rep Online. 2010 December 1; 66(Pt 12): o3138–o3139.
Published online 2010 November 13. doi:  10.1107/S1600536810045939
PMCID: PMC3011427

3-Diethyl­amino-6-[(Z)-(4-hy­droxy­anilino)methyl­idene]cyclo­hexa-2,4-dienone

Abstract

In the mol­ecule of the title compound, C17H20N2O2, the aromatic rings are oriented at a dihedral angle of 6.23 (22)°. Intra­molecular N—H(...)O hydrogen bonding involving the amine H atom and the carbonyl O atom affects the conformation of the mol­ecule. One of the ethyl arms is disordered over two conformations, with occupancies of 0.59 (2) and 0.41 (2). The crystal packing is stabilized by inter­molecular C—H(...)O and O—H(...)O hydrogen bonds, and weak C—H(...)π inter­actions.

Related literature

For general background to Schiff bases, see: Odabaşoğlu et al. (2004 [triangle]); Hadjoudis et al. (1987 [triangle]); Hodnett & Dunn (1970 [triangle]); Misra et al. (1981 [triangle]); Agarwal et al. (1983 [triangle]); Varma et al. (1986 [triangle]); Singh & Dash (1988 [triangle]); Pandey et al. (1999 [triangle]); El-Masry et al. (2000 [triangle]); Samadhiya & Halve (2001 [triangle]); Xu et al. (1994 [triangle]); Calligaris et al. (1972 [triangle]); Cohen et al. (1964 [triangle]); Moustakali-Mavridis et al. (1978 [triangle]). For related strucures: Ersanlı et al. (2003 [triangle]); Şahin et al. (2005 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o3138-scheme1.jpg

Experimental

Crystal data

  • C17H20N2O2
  • M r = 284.35
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o3138-efi3.jpg
  • a = 8.2648 (4) Å
  • b = 11.8968 (4) Å
  • c = 16.6149 (7) Å
  • β = 112.400 (3)°
  • V = 1510.39 (11) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 296 K
  • 0.54 × 0.44 × 0.26 mm

Data collection

  • Stoe IPDS 2 diffractometer
  • Absorption correction: integration (X-RED32; Stoe & Cie, 2002 [triangle]) T min = 0.957, T max = 0.979
  • 18967 measured reflections
  • 3143 independent reflections
  • 2416 reflections with I > 2σ(I)
  • R int = 0.067

Refinement

  • R[F 2 > 2σ(F 2)] = 0.065
  • wR(F 2) = 0.189
  • S = 1.06
  • 3143 reflections
  • 208 parameters
  • 13 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.37 e Å−3
  • Δρmin = −0.27 e Å−3

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

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810045939/si2307sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810045939/si2307Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors wish to acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDS 2 diffractometer (purchased under grant No. F279 of the University Research Fund).

supplementary crystallographic information

Comment

Schiff bases are used as substrates in the preparation of number of industrial and biologically active compounds via ring closure, cycloaddition and replacement reactions.Some Schiff base derivatives are also known to have biological activities such as antimicrobial (El-Masry et al., 2000; Pandey et al., 1999); antifungal (Singh & Dash 1988; Varma et al., 1986); antitumor (Hodnett & Dunn 1970; Misra et al., 1981; Agarwal et al., 1983) and as herbicides (Samadhiya & Halve, 2001). In additin, Schiff bases have been used widely as ligands in the field of coordinatin chemistry (Calligaris et al., 1972). There are two caracteri properties of Schiff bases, viz. photochromism and thermochromism (Cohen et al., 1964; Moustakali-Mavridis et al., 1978). These properties result from proton transfer from the O atom to the imin N atom (Hadjoudis et al., 1987; Xu et al., 1994).

In the molecule of (I), the C13=O2 and N1—C7 bond lengths of 1.301 (2) and 1.307 (3) Å, respectively are in good agreement with those observed in 2-[(2-hydroxy-4-nitrophenyl)aminomethylene]cyclohexa-3,5-dien-1(2H)-one [1.298 (2) and 1.308 (2) Å; Ersanlı et al., 2003] and 2-Hydroxy-6-[(2-methoxyphenyl)aminomethylene]cyclohexa-2,4-dienone [1.2931 (17) and 1.3043 (19) Å; Şahin et al., 2005]. The study of Schiff bases has led to the proposal that molecules exhibiting thermochromism are planar, while those exhibiting photochromism are non-planar. This planarity of the molecule allows the proton to be transferred through the hydrogen bond in the ground state with a small energy requirement (Odabaşoǧlu et al., 2004; Hadjoudis et al., 1987). The dihedral angle between benzene rings A(C1—C6) and B(C8—C13) is 6.49 (22)° (Fig.1). These two rings are twisted slightly about the methylene amino group with torsion angles of -0.5 (3)° [C2—C1—N1—C7] and 179.48 (18)° [N1—C7—C8—C9], respectively. C16 was disordered over two positions A and B (C16A and C16B) wiht the occupancy factors refined to 0.59 (2) and 0.41 (2). Intramolecular N1—H1A···O2 hydrogen bonding contributes to the overall planarity of the molecule. In crystal packing, the weak [C5—H6···Cg1(x,- 1/2 - y, - 1/2 + z)] interaction, and the hydrogen bonds [C16A—H16A···O2(1 - x,1/2 + y,1/2 - z)] and [O1—H1A···O2(1 + x,1/2 - y,1/2 + z)] are listed in Table 1 and labelled in Fig.2.

Experimental

The compound (Z)-6-[(4-hydroxyphenylamino)methylene]-3 -(diethylamino)cyclohexa-2,4-dienone was prepared by refluxing a mixture of a solution containing 5-(diethylamino)-2-hydroxybenzaldehyde (0.5 g, 2.59 mmol) in 20 ml e thanol and a solution containing 4-hydroxyaniline (0.28 g, 2.59 mmol) in 20 ml e thanol. The reaction mixture was stirred for 1 h under reflux. The crystals of the title compound were obtained by slow evaporation from ethyl alcohol (yield % 73; m.p. 468–470 K).

Refinement

All H atoms were placed in calculated positions except H1A and H1B which were located in a difference fourier map. All carbon-bound H atoms were refined using a riding model with C—H = 0.93 to 0.97 Å and Uiso(H) = 1.2–1.5 Ueq (C).

Figures

Fig. 1.
An ORTEP view of (I), with the atom-numbering scheme and 30% probability displacement ellipsoids. Only the major disorder component C16A are displayed. The dashed line indicates the intramolecular hydrogen bond.
Fig. 2.
A packing diagram for (I), hydrogen bonds and C—H···π interaction are drawn as dashed lines. [Symmetry codes: (i) 1 - x,1/2 + y, 1/2 + z; (ii) x + 1,1/2 - y, 1/2 - z; (iii) x,1/2 - y,1/2 + z]

Crystal data

C17H20N2O2F(000) = 608
Mr = 284.35Dx = 1.250 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 18967 reflections
a = 8.2648 (4) Åθ = 1.7–28.0°
b = 11.8968 (4) ŵ = 0.08 mm1
c = 16.6149 (7) ÅT = 296 K
β = 112.400 (3)°Prism, brown
V = 1510.39 (11) Å30.54 × 0.44 × 0.26 mm
Z = 4

Data collection

Stoe IPDS 2 diffractometer3143 independent reflections
Radiation source: fine-focus sealed tube2416 reflections with I > 2σ(I)
graphiteRint = 0.067
Detector resolution: 6.67 pixels mm-1θmax = 26.5°, θmin = 2.2°
rotation method scansh = −10→10
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)k = −14→14
Tmin = 0.957, Tmax = 0.979l = −20→20
18967 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.065Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.189H atoms treated by a mixture of independent and constrained refinement
S = 1.06w = 1/[σ2(Fo2) + (0.0969P)2 + 0.3716P] where P = (Fo2 + 2Fc2)/3
3143 reflections(Δ/σ)max < 0.001
208 parametersΔρmax = 0.37 e Å3
13 restraintsΔρmin = −0.27 e Å3

Special details

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)

xyzUiso*/UeqOcc. (<1)
C10.8028 (2)0.31443 (16)0.65717 (13)0.0483 (5)
C20.9660 (3)0.35845 (19)0.70654 (14)0.0549 (5)
H31.01260.41630.68440.066*
C31.0587 (3)0.31624 (19)0.78840 (14)0.0581 (5)
H21.16800.34630.82120.070*
C40.9927 (3)0.22989 (19)0.82301 (13)0.0550 (5)
C50.8278 (3)0.1876 (2)0.77383 (16)0.0627 (6)
H60.78000.13090.79630.075*
C60.7352 (3)0.22939 (19)0.69203 (15)0.0593 (6)
H50.62530.20010.65950.071*
C70.7361 (2)0.42738 (17)0.52483 (13)0.0501 (5)
H70.83860.46890.54950.060*
C80.6253 (2)0.44989 (16)0.43902 (12)0.0470 (5)
C90.6675 (3)0.53469 (18)0.39085 (14)0.0536 (5)
H90.76880.57660.41800.064*
C100.5666 (3)0.55735 (19)0.30686 (14)0.0567 (5)
H100.60000.61340.27740.068*
C110.4090 (3)0.49573 (19)0.26311 (13)0.0556 (5)
C120.3648 (3)0.41193 (19)0.30976 (13)0.0552 (5)
H120.26380.37010.28160.066*
C130.4654 (2)0.38791 (17)0.39687 (12)0.0473 (5)
C140.1382 (4)0.4570 (2)0.13497 (16)0.0802 (8)
H15A0.06000.50230.08750.096*
H15B0.08190.44470.17590.096*
C150.3476 (4)0.6042 (3)0.12686 (17)0.0855 (8)
H14A0.40630.66710.16340.103*
H14B0.24160.63190.08150.103*
C16A0.4682 (17)0.5521 (6)0.0854 (7)0.096 (3)0.59 (2)
H16A0.49600.60780.05080.144*0.59 (2)
H16B0.40970.49000.04910.144*0.59 (2)
H16C0.57410.52620.13040.144*0.59 (2)
C16B0.388 (3)0.5630 (9)0.0567 (10)0.097 (4)0.41 (2)
H16D0.41410.62490.02670.145*0.41 (2)
H16E0.28880.52240.01710.145*0.41 (2)
H16F0.48680.51370.07850.145*0.41 (2)
C170.1651 (5)0.3472 (3)0.1001 (2)0.1033 (11)
H17A0.05430.31020.07250.155*
H17B0.24060.30130.14680.155*
H17C0.21770.35880.05830.155*
N10.7013 (2)0.35026 (14)0.57193 (11)0.0500 (4)
H1B0.597 (3)0.316 (2)0.5437 (17)0.066 (7)*
N20.3028 (3)0.51988 (19)0.17918 (12)0.0712 (6)
O11.0820 (2)0.18478 (17)0.90278 (11)0.0723 (5)
H1A1.193 (5)0.197 (3)0.919 (3)0.131 (14)*
O20.41712 (18)0.31201 (13)0.43958 (9)0.0573 (4)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0409 (9)0.0490 (11)0.0465 (10)0.0055 (8)0.0073 (8)−0.0005 (8)
C20.0445 (10)0.0592 (12)0.0530 (12)−0.0014 (9)0.0097 (9)0.0059 (10)
C30.0429 (10)0.0648 (13)0.0548 (12)0.0007 (9)0.0053 (9)−0.0002 (10)
C40.0488 (10)0.0650 (13)0.0471 (11)0.0128 (9)0.0135 (9)0.0064 (9)
C50.0546 (11)0.0642 (14)0.0655 (14)0.0015 (10)0.0185 (11)0.0146 (11)
C60.0444 (10)0.0603 (13)0.0619 (13)−0.0036 (9)0.0076 (9)0.0058 (10)
C70.0429 (9)0.0485 (10)0.0525 (11)0.0005 (8)0.0109 (8)−0.0046 (9)
C80.0449 (9)0.0468 (10)0.0456 (10)0.0028 (8)0.0129 (8)−0.0024 (8)
C90.0497 (10)0.0532 (11)0.0560 (12)−0.0039 (9)0.0178 (9)−0.0026 (9)
C100.0634 (12)0.0543 (12)0.0568 (12)−0.0037 (10)0.0279 (10)0.0028 (10)
C110.0632 (12)0.0575 (12)0.0430 (10)0.0009 (10)0.0167 (9)0.0002 (9)
C120.0554 (11)0.0583 (12)0.0428 (10)−0.0078 (9)0.0086 (9)−0.0013 (9)
C130.0471 (10)0.0473 (10)0.0433 (10)0.0010 (8)0.0125 (8)−0.0015 (8)
C140.0868 (16)0.0904 (19)0.0479 (13)−0.0054 (12)0.0081 (12)0.0082 (12)
C150.119 (2)0.0810 (18)0.0530 (14)−0.0084 (16)0.0290 (15)0.0098 (13)
C16A0.097 (3)0.096 (3)0.096 (3)−0.0016 (10)0.0374 (14)0.0005 (10)
C16B0.097 (4)0.097 (4)0.096 (4)−0.0010 (10)0.0381 (18)0.0011 (10)
C170.138 (3)0.095 (2)0.0714 (19)−0.017 (2)0.0339 (19)−0.0090 (17)
N10.0400 (8)0.0524 (10)0.0467 (9)−0.0004 (7)0.0044 (7)−0.0006 (7)
N20.0859 (13)0.0756 (13)0.0445 (10)−0.0067 (10)0.0161 (9)0.0084 (9)
O10.0591 (10)0.0981 (14)0.0537 (9)0.0155 (9)0.0147 (8)0.0213 (9)
O20.0523 (8)0.0624 (9)0.0452 (8)−0.0123 (6)0.0050 (6)0.0069 (7)

Geometric parameters (Å, °)

C1—C61.385 (3)C12—C131.397 (3)
C1—C21.387 (3)C12—H120.9300
C1—N11.409 (3)C13—O21.301 (2)
C2—C31.377 (3)C14—N21.479 (3)
C2—H30.9300C14—C171.481 (4)
C3—C41.387 (3)C14—H15A0.9700
C3—H20.9300C14—H15B0.9700
C4—O11.358 (3)C15—C16B1.415 (9)
C4—C51.389 (3)C15—N21.465 (3)
C5—C61.374 (3)C15—C16A1.541 (8)
C5—H60.9300C15—H14A0.9700
C6—H50.9300C15—H14B0.9700
C7—N11.307 (3)C16A—H16A0.9600
C7—C81.396 (3)C16A—H16B0.9600
C7—H70.9300C16A—H16C0.9600
C8—C91.412 (3)C16B—H16D0.9600
C8—C131.441 (3)C16B—H16E0.9600
C9—C101.352 (3)C16B—H16F0.9600
C9—H90.9300C17—H17A0.9600
C10—C111.429 (3)C17—H17B0.9600
C10—H100.9300C17—H17C0.9600
C11—N21.366 (3)N1—H1B0.90 (3)
C11—C121.394 (3)O1—H1A0.87 (4)
C6—C1—C2119.00 (19)N2—C14—H15A108.9
C6—C1—N1117.45 (17)C17—C14—H15A108.9
C2—C1—N1123.54 (19)N2—C14—H15B108.9
C3—C2—C1119.8 (2)C17—C14—H15B108.9
C3—C2—H3120.1H15A—C14—H15B107.8
C1—C2—H3120.1C16B—C15—N2116.3 (5)
C2—C3—C4121.39 (19)N2—C15—C16A110.1 (4)
C2—C3—H2119.3C16B—C15—H14A124.5
C4—C3—H2119.3N2—C15—H14A109.6
O1—C4—C3123.0 (2)C16A—C15—H14A109.6
O1—C4—C5118.5 (2)C16B—C15—H14B84.4
C3—C4—C5118.50 (19)N2—C15—H14B109.6
C6—C5—C4120.2 (2)C16A—C15—H14B109.6
C6—C5—H6119.9H14A—C15—H14B108.2
C4—C5—H6119.9C15—C16A—H16A109.5
C5—C6—C1121.10 (19)C15—C16A—H16B109.5
C5—C6—H5119.4H16A—C16A—H16B109.5
C1—C6—H5119.4C15—C16A—H16C109.5
N1—C7—C8122.57 (18)H16A—C16A—H16C109.5
N1—C7—H7118.7H16B—C16A—H16C109.5
C8—C7—H7118.7C15—C16B—H16D109.5
C7—C8—C9120.58 (18)C15—C16B—H16E109.5
C7—C8—C13121.43 (18)H16D—C16B—H16E109.5
C9—C8—C13118.00 (17)C15—C16B—H16F109.5
C10—C9—C8122.60 (19)H16D—C16B—H16F109.5
C10—C9—H9118.7H16E—C16B—H16F109.5
C8—C9—H9118.7C14—C17—H17A109.5
C9—C10—C11120.5 (2)C14—C17—H17B109.5
C9—C10—H10119.8H17A—C17—H17B109.5
C11—C10—H10119.8C14—C17—H17C109.5
N2—C11—C12121.0 (2)H17A—C17—H17C109.5
N2—C11—C10121.2 (2)H17B—C17—H17C109.5
C12—C11—C10117.73 (19)C7—N1—C1129.19 (18)
C11—C12—C13122.95 (19)C7—N1—H1B112.7 (16)
C11—C12—H12118.5C1—N1—H1B118.1 (16)
C13—C12—H12118.5C11—N2—C15122.7 (2)
O2—C13—C12121.47 (18)C11—N2—C14120.8 (2)
O2—C13—C8120.34 (17)C15—N2—C14116.4 (2)
C12—C13—C8118.20 (19)C4—O1—H1A111 (3)
N2—C14—C17113.2 (3)
C6—C1—C2—C30.9 (3)C11—C12—C13—O2177.4 (2)
N1—C1—C2—C3−178.06 (19)C11—C12—C13—C8−2.5 (3)
C1—C2—C3—C40.1 (3)C7—C8—C13—O22.8 (3)
C2—C3—C4—O1178.7 (2)C9—C8—C13—O2−177.25 (18)
C2—C3—C4—C5−1.3 (3)C7—C8—C13—C12−177.39 (19)
O1—C4—C5—C6−178.5 (2)C9—C8—C13—C122.6 (3)
C3—C4—C5—C61.5 (3)C8—C7—N1—C1176.75 (18)
C4—C5—C6—C1−0.5 (4)C6—C1—N1—C7−179.4 (2)
C2—C1—C6—C5−0.7 (3)C2—C1—N1—C7−0.5 (3)
N1—C1—C6—C5178.3 (2)C12—C11—N2—C15−177.6 (2)
N1—C7—C8—C9179.48 (18)C10—C11—N2—C154.1 (4)
N1—C7—C8—C13−0.5 (3)C12—C11—N2—C14−0.5 (4)
C7—C8—C9—C10178.19 (19)C10—C11—N2—C14−178.9 (2)
C13—C8—C9—C10−1.8 (3)C16B—C15—N2—C11110.8 (10)
C8—C9—C10—C110.7 (3)C16A—C15—N2—C1183.7 (6)
C9—C10—C11—N2177.9 (2)C16B—C15—N2—C14−66.3 (10)
C9—C10—C11—C12−0.4 (3)C16A—C15—N2—C14−93.5 (6)
N2—C11—C12—C13−177.0 (2)C17—C14—N2—C11−81.1 (3)
C10—C11—C12—C131.4 (3)C17—C14—N2—C1596.1 (3)

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C8–C13 ring.
D—H···AD—HH···AD···AD—H···A
N1—H1B···O20.90 (3)1.80 (3)2.574 (2)142 (2)
O1—H1A···O2i0.87 (4)1.75 (4)2.599 (2)165 (4)
C16A—H16A···O2ii0.962.523.306 (7)139
C5—H6···Cg1iii0.932.933.799 (3)156

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SI2307).

References

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