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In the structure of the title compound, C22H24N2O3, short intermolecular C—H...O contacts influence the crystal packing and molecular ladders are formed. Intramolecular N—H...O hydrogen bonds make the Z configuration stable by formation of six-membered rings.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536802017336/cf6201sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536802017336/cf6201Isup2.hkl
Contains datablock I

CCDC reference: 189663

Key indicators

  • Single-crystal X-ray study
  • T = 296 K
  • Mean [sigma](C-C) = 0.003 Å
  • R factor = 0.038
  • wR factor = 0.106
  • Data-to-parameter ratio = 14.1

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


Red Alert Alert Level A:
PLAT_724 Alert A Contact Calc 24.26760, Rep 2.54000, Dev. 21.73 Ang. H8C -O2 1.555 4.565 PLAT_724 Alert A Contact Calc 21.90940, Rep 2.60000, Dev. 19.31 Ang. H16 -O2 1.555 4.465
2 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
0 Alert Level C = Please check

Comment top

Schiff bases are becoming increasingly important as biological, analytical, pharmacological and antimicrobial reagents in coordination chemistry. There are many reports of Schiff bases obtained by condensation between the NH2 group of an amine and the carbonyl group of aldehydes/ketones (Ismail, 2000; Raman et al., 2001; Daniel Thangadurai & Natarajan, 2000). A literature survey revealed fewer results involving isomers of Schiff bases. We obtained the title compound, (I), by the usual type of condensation; however, the expected C—CN group is, in fact, CC—N.

A view of the molecule of (I) is shown in Fig. 1. The dihedral angle between the two planes defined by O1 and each of the two phenyl rings is 73.39 (7)%. The N1—H1N···O2 and N2—H2N···O3 hydrogen bond stablize the Z configuration of the CC bonds by forming six-membered rings (Table 2). The torsion angles C7—C9—C10—O2 [1.3 (3)%] and C7—C9—C10—C11 [−177.81 (19)%] indicate that the group N1/C7/C8/C9/C10/C11/O2 is nearly planar; the group N2/C18/C19/C20/C21/C22/O3 is not slightly more non-planar, as is evident from the torsion angles C18—C20—C21—O3 [−2.3 (3)%] and C18—C20—C21—C22 [175.70 (18)%]. The dihedral angle between these two groups is 88.21 (6)%. The two halves of the molecule resemble each other in geometry (Table 1).

The short intermolecular C—H···O contacts (Table 2) involving both ketone functions are respectively 0.19, 0.18 and 0.12 Å shorter than the sum of van der Waals radii (Bondi, 1964). They may be classified as weak to very weak hydrogen bonds (Desiraju & Steiner, 1999), and the second is near-linear (Jeffrey et al., 1985). Examination of the structure with PLATON (Spek, 2002) shows that there are no solvent-accessible voids.

The intermolecular C—H···O contacts link molecules into dimers, dimers face-to-face to form four-molecule aggregates, and aggregates into ladders, to give a two-demensional network (Fig. 2).

Experimental top

The title compound was prepared by the condensation in ethanol of 4,4'-diamino-diphenyl ether (0.5 mol) with 2,4-dipentone (1.0 mol). The solution was stirred for 2 h at 433 K. Crystals suitable for diffraction study were obtained after one month (m.p. 428 K). Spectroscopic analysis, 1H NMR (CDCl3, δ, p.p.m.): 1.97 (s, 6H), 2.10 (s, 6H), 5.19 (s, 1H), 7.04 (m, 8H), 12.39 (s, 1H).

Refinement top

All H atoms were generated geometrically and refined using a riding model, with C—H = 0.93 Å for aromatic H atoms and 0.96 Å for methyl H atoms, N—H = 0.86 Å, and Uiso(H) = 1.2Ueq of the parent atoms.

Computing details top

Data collection: XSCANS (Fait, 1991); cell refinement: XSCANS; data reduction: SHELXTL (Sheldrick, 1997b); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as spheres of arbitrary radii.
[Figure 2] Fig. 2. A packing diagram for (I). H atoms have been omitted for clarity.
(Z)-4-(4-{4-[(Z)-1-Methyl-3-oxobut-1-enylamino]phenoxy}phenylamino)pent-3-en- 2-one top
Crystal data top
C22H24N2O3F(000) = 776
Mr = 364.43Dx = 1.209 Mg m3
Monoclinic, P21/cMelting point: 160 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 8.769 (1) ÅCell parameters from 26 reflections
b = 20.073 (4) Åθ = 3.2–15.2°
c = 11.928 (2) ŵ = 0.08 mm1
β = 107.53 (1)°T = 296 K
V = 2002.1 (6) Å3Monoclinic, yellow
Z = 40.54 × 0.52 × 0.44 mm
Data collection top
Siemens P4
diffractometer
Rint = 0.010
Radiation source: normal-focus sealed tubeθmax = 25.0°, θmin = 2.0°
Graphite monochromatorh = 010
ω scansk = 023
3762 measured reflectionsl = 1413
3520 independent reflections3 standard reflections every 97 reflections
2338 reflections with I > 2σ(I) intensity decay: 4.4%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.038H-atom parameters constrained
wR(F2) = 0.106 w = 1/[σ2(Fo2) + (0.0609P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.98(Δ/σ)max < 0.001
3520 reflectionsΔρmax = 0.16 e Å3
249 parametersΔρmin = 0.15 e Å3
0 restraintsExtinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0223 (19)
Crystal data top
C22H24N2O3V = 2002.1 (6) Å3
Mr = 364.43Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.769 (1) ŵ = 0.08 mm1
b = 20.073 (4) ÅT = 296 K
c = 11.928 (2) Å0.54 × 0.52 × 0.44 mm
β = 107.53 (1)°
Data collection top
Siemens P4
diffractometer
Rint = 0.010
3762 measured reflections3 standard reflections every 97 reflections
3520 independent reflections intensity decay: 4.4%
2338 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.106H-atom parameters constrained
S = 0.98Δρmax = 0.16 e Å3
3520 reflectionsΔρmin = 0.15 e Å3
249 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
xyzUiso*/Ueq
O10.92145 (14)0.62846 (6)0.35108 (10)0.0635 (4)
O21.69208 (15)0.81683 (6)0.35141 (11)0.0683 (4)
O30.35937 (14)0.60130 (6)0.73952 (10)0.0636 (4)
N11.47304 (16)0.78311 (7)0.45227 (12)0.0559 (4)
H1N1.50350.78810.39070.067*
N20.60387 (17)0.55880 (7)0.67380 (12)0.0546 (4)
H2N0.53360.58850.67510.066*
C11.05639 (19)0.66896 (8)0.38356 (14)0.0487 (4)
C21.0751 (2)0.71426 (9)0.30265 (15)0.0583 (5)
H20.99560.71920.23110.070*
C31.2122 (2)0.75256 (9)0.32761 (14)0.0563 (5)
H31.22470.78330.27270.068*
C41.33097 (19)0.74546 (8)0.43388 (14)0.0482 (4)
C51.3103 (2)0.69937 (8)0.51422 (14)0.0512 (4)
H51.38990.69380.58550.061*
C61.1729 (2)0.66161 (8)0.48979 (15)0.0519 (4)
H61.15910.63130.54490.062*
C71.5679 (2)0.81219 (8)0.54934 (14)0.0492 (4)
C81.5212 (2)0.81218 (9)0.66039 (15)0.0659 (5)
H8A1.40710.81580.64130.079*
H8B1.57070.84930.70850.079*
H8C1.55600.77140.70240.079*
C91.7058 (2)0.84277 (9)0.54584 (15)0.0562 (5)
H91.76610.86470.61330.067*
C101.7636 (2)0.84345 (9)0.44711 (18)0.0596 (5)
C111.9204 (3)0.87707 (13)0.4580 (2)0.0959 (8)
H11A2.00580.84550.48500.115*
H11B1.93570.91310.51320.115*
H11C1.91990.89410.38270.115*
C120.85222 (19)0.61089 (9)0.43774 (14)0.0506 (4)
C130.8098 (2)0.54588 (9)0.44410 (15)0.0593 (5)
H130.83580.51410.39600.071*
C140.7283 (2)0.52713 (9)0.52186 (16)0.0589 (5)
H140.69630.48310.52400.071*
C150.69427 (19)0.57348 (8)0.59622 (14)0.0484 (4)
C160.7400 (2)0.63882 (8)0.59033 (17)0.0598 (5)
H160.71890.67030.64090.072*
C170.8168 (2)0.65795 (9)0.50999 (17)0.0630 (5)
H170.84440.70230.50480.076*
C180.6086 (2)0.50707 (8)0.74516 (15)0.0523 (4)
C190.7301 (3)0.45345 (10)0.7543 (2)0.0850 (7)
H19A0.68950.42150.69260.102*
H19B0.75190.43170.82920.102*
H19C0.82690.47270.74700.102*
C200.5030 (2)0.50409 (9)0.80976 (15)0.0558 (5)
H200.51280.46870.86170.067*
C210.3804 (2)0.55107 (9)0.80295 (14)0.0526 (4)
C220.2654 (3)0.53914 (11)0.87256 (19)0.0815 (6)
H22A0.26640.57680.92240.098*
H22B0.29700.50000.92000.098*
H22C0.15960.53300.81970.098*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0600 (8)0.0837 (9)0.0490 (7)0.0247 (7)0.0197 (6)0.0044 (6)
O20.0692 (8)0.0803 (9)0.0606 (8)0.0169 (7)0.0274 (7)0.0014 (7)
O30.0677 (8)0.0636 (8)0.0643 (8)0.0171 (7)0.0273 (7)0.0143 (7)
N10.0555 (9)0.0692 (10)0.0445 (8)0.0133 (7)0.0174 (7)0.0023 (7)
N20.0556 (9)0.0495 (8)0.0658 (9)0.0063 (7)0.0289 (8)0.0091 (7)
C10.0471 (10)0.0572 (10)0.0445 (9)0.0062 (8)0.0180 (8)0.0025 (8)
C20.0558 (11)0.0734 (12)0.0436 (9)0.0089 (9)0.0117 (8)0.0063 (9)
C30.0628 (11)0.0629 (11)0.0432 (9)0.0090 (9)0.0158 (9)0.0103 (8)
C40.0474 (9)0.0533 (10)0.0473 (9)0.0041 (8)0.0193 (8)0.0019 (8)
C50.0467 (10)0.0579 (10)0.0474 (9)0.0015 (8)0.0115 (8)0.0091 (8)
C60.0534 (10)0.0552 (10)0.0505 (10)0.0023 (9)0.0208 (8)0.0097 (8)
C70.0535 (10)0.0446 (9)0.0470 (9)0.0045 (8)0.0114 (8)0.0044 (8)
C80.0803 (14)0.0636 (12)0.0566 (11)0.0011 (10)0.0249 (10)0.0035 (9)
C90.0552 (10)0.0549 (10)0.0535 (10)0.0048 (9)0.0085 (9)0.0021 (8)
C100.0516 (11)0.0558 (11)0.0690 (12)0.0033 (9)0.0147 (10)0.0052 (9)
C110.0664 (14)0.117 (2)0.1059 (18)0.0299 (13)0.0282 (13)0.0030 (15)
C120.0429 (9)0.0645 (12)0.0446 (9)0.0096 (8)0.0136 (8)0.0008 (8)
C130.0638 (12)0.0634 (12)0.0545 (10)0.0129 (9)0.0235 (9)0.0136 (9)
C140.0670 (12)0.0500 (10)0.0638 (11)0.0144 (9)0.0257 (10)0.0062 (9)
C150.0438 (9)0.0493 (10)0.0540 (10)0.0007 (8)0.0174 (8)0.0036 (8)
C160.0683 (12)0.0471 (10)0.0751 (12)0.0030 (9)0.0384 (10)0.0005 (9)
C170.0712 (12)0.0464 (10)0.0819 (13)0.0042 (9)0.0387 (11)0.0048 (10)
C180.0511 (10)0.0492 (10)0.0556 (10)0.0034 (8)0.0149 (9)0.0062 (8)
C190.0886 (16)0.0806 (15)0.0990 (16)0.0319 (12)0.0481 (14)0.0344 (13)
C200.0611 (11)0.0551 (11)0.0535 (10)0.0037 (9)0.0207 (9)0.0130 (8)
C210.0526 (10)0.0615 (11)0.0445 (9)0.0005 (9)0.0158 (8)0.0007 (9)
C220.0814 (14)0.0997 (17)0.0770 (13)0.0151 (13)0.0443 (12)0.0142 (12)
Geometric parameters (Å, º) top
O1—C11.3911 (19)C9—H90.930
O1—C121.3926 (19)C10—C111.502 (3)
O2—C101.245 (2)C11—H11A0.960
O3—C211.2406 (19)C11—H11B0.960
N1—C71.339 (2)C11—H11C0.960
N1—C41.417 (2)C12—C131.365 (2)
N1—H1N0.860C12—C171.376 (2)
N2—C181.335 (2)C13—C141.383 (2)
N2—C151.419 (2)C13—H130.930
N2—H2N0.860C14—C151.379 (2)
C1—C21.371 (2)C14—H140.930
C1—C61.375 (2)C15—C161.380 (2)
C2—C31.382 (2)C16—C171.381 (2)
C2—H20.930C16—H160.930
C3—C41.385 (2)C17—H170.930
C3—H30.930C18—C201.373 (2)
C4—C51.383 (2)C18—C191.495 (2)
C5—C61.378 (2)C19—H19A0.960
C5—H50.930C19—H19B0.960
C6—H60.930C19—H19C0.960
C7—C91.368 (2)C20—C211.414 (2)
C7—C81.500 (2)C20—H200.930
C8—H8A0.960C21—C221.505 (2)
C8—H8B0.960C22—H22A0.960
C8—H8C0.960C22—H22B0.960
C9—C101.415 (2)C22—H22C0.960
H8C···O2i2.54H16···O2ii2.60
C1—O1—C12117.75 (12)C10—C11—H11C109.5
C7—N1—C4130.90 (14)H11A—C11—H11C109.5
C7—N1—H1N114.5H11B—C11—H11C109.5
C4—N1—H1N114.5C13—C12—C17120.31 (15)
C18—N2—C15131.37 (14)C13—C12—O1118.05 (15)
C18—N2—H2N114.3C17—C12—O1121.48 (15)
C15—N2—H2N114.3C12—C13—C14120.13 (17)
C2—C1—C6120.43 (15)C12—C13—H13119.9
C2—C1—O1117.61 (15)C14—C13—H13119.9
C6—C1—O1121.84 (14)C15—C14—C13120.24 (16)
C1—C2—C3119.86 (16)C15—C14—H14119.9
C1—C2—H2120.1C13—C14—H14119.9
C3—C2—H2120.1C14—C15—C16119.09 (16)
C2—C3—C4120.40 (15)C14—C15—N2123.45 (15)
C2—C3—H3119.8C16—C15—N2117.30 (15)
C4—C3—H3119.8C15—C16—C17120.64 (16)
C5—C4—C3118.94 (15)C15—C16—H16119.7
C5—C4—N1122.85 (15)C17—C16—H16119.7
C3—C4—N1118.10 (14)C12—C17—C16119.53 (16)
C6—C5—C4120.67 (16)C12—C17—H17120.2
C6—C5—H5119.7C16—C17—H17120.2
C4—C5—H5119.7N2—C18—C20119.66 (15)
C1—C6—C5119.70 (15)N2—C18—C19119.41 (16)
C1—C6—H6120.2C20—C18—C19120.92 (16)
C5—C6—H6120.2C18—C19—H19A109.5
N1—C7—C9119.59 (15)C18—C19—H19B109.5
N1—C7—C8119.99 (15)H19A—C19—H19B109.5
C9—C7—C8120.41 (16)C18—C19—H19C109.5
C7—C8—H8A109.5H19A—C19—H19C109.5
C7—C8—H8B109.5H19B—C19—H19C109.5
H8A—C8—H8B109.5C18—C20—C21124.65 (16)
C7—C8—H8C109.5C18—C20—H20117.7
H8A—C8—H8C109.5C21—C20—H20117.7
H8B—C8—H8C109.5O3—C21—C20123.20 (16)
C7—C9—C10124.82 (17)O3—C21—C22117.68 (16)
C7—C9—H9117.6C20—C21—C22119.09 (16)
C10—C9—H9117.6C21—C22—H22A109.5
O2—C10—C9123.44 (16)C21—C22—H22B109.5
O2—C10—C11117.84 (18)H22A—C22—H22B109.5
C9—C10—C11118.71 (19)C21—C22—H22C109.5
C10—C11—H11A109.5H22A—C22—H22C109.5
C10—C11—H11B109.5H22B—C22—H22C109.5
H11A—C11—H11B109.5
C12—O1—C1—C2145.43 (16)C1—O1—C12—C13134.49 (16)
C12—O1—C1—C638.6 (2)C1—O1—C12—C1750.0 (2)
C6—C1—C2—C30.3 (3)C17—C12—C13—C141.2 (3)
O1—C1—C2—C3175.70 (15)O1—C12—C13—C14174.42 (15)
C1—C2—C3—C40.0 (3)C12—C13—C14—C152.2 (3)
C2—C3—C4—C50.2 (3)C13—C14—C15—C161.2 (3)
C2—C3—C4—N1176.38 (16)C13—C14—C15—N2176.52 (16)
C7—N1—C4—C540.1 (3)C18—N2—C15—C1444.0 (3)
C7—N1—C4—C3143.88 (18)C18—N2—C15—C16140.55 (19)
C3—C4—C5—C60.8 (2)C14—C15—C16—C170.9 (3)
N1—C4—C5—C6176.80 (15)N2—C15—C16—C17174.69 (16)
C2—C1—C6—C51.0 (3)C13—C12—C17—C160.9 (3)
O1—C1—C6—C5174.93 (15)O1—C12—C17—C16176.37 (16)
C4—C5—C6—C11.2 (3)C15—C16—C17—C122.0 (3)
C4—N1—C7—C9175.96 (17)C15—N2—C18—C20178.18 (16)
C4—N1—C7—C85.1 (3)C15—N2—C18—C192.4 (3)
N1—C7—C9—C103.6 (3)N2—C18—C20—C213.3 (3)
C8—C7—C9—C10177.49 (17)C19—C18—C20—C21177.29 (18)
C7—C9—C10—O21.3 (3)C18—C20—C21—O32.3 (3)
C7—C9—C10—C11177.81 (19)C18—C20—C21—C22175.70 (18)
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x1, y+1/2, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O20.861.942.643 (2)139
N2—H2N···O30.861.922.637 (2)139
C6—H6···O3iii0.932.533.175 (2)127
Symmetry code: (iii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC22H24N2O3
Mr364.43
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)8.769 (1), 20.073 (4), 11.928 (2)
β (°) 107.53 (1)
V3)2002.1 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.54 × 0.52 × 0.44
Data collection
DiffractometerSiemens P4
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
3762, 3520, 2338
Rint0.010
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.106, 0.98
No. of reflections3520
No. of parameters249
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.16, 0.15

Computer programs: XSCANS (Fait, 1991), XSCANS, SHELXTL (Sheldrick, 1997b), SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997a), ORTEP-3 for Windows (Farrugia, 1997), SHELXTL.

Selected geometric parameters (Å, º) top
O1—C11.3911 (19)N1—C41.417 (2)
O1—C121.3926 (19)N2—C181.335 (2)
O2—C101.245 (2)N2—C151.419 (2)
O3—C211.2406 (19)C7—C91.368 (2)
N1—C71.339 (2)C18—C201.373 (2)
H8C···O2i2.54H16···O2ii2.60
C1—O1—C12117.75 (12)N1—C7—C8119.99 (15)
C7—N1—C4130.90 (14)C14—C15—N2123.45 (15)
C18—N2—C15131.37 (14)C16—C15—N2117.30 (15)
C5—C4—N1122.85 (15)N2—C18—C20119.66 (15)
C3—C4—N1118.10 (14)N2—C18—C19119.41 (16)
N1—C7—C9119.59 (15)
C4—N1—C7—C9175.96 (17)C15—N2—C18—C20178.18 (16)
N1—C7—C9—C103.6 (3)N2—C18—C20—C213.3 (3)
C7—C9—C10—O21.3 (3)C18—C20—C21—O32.3 (3)
C7—C9—C10—C11177.81 (19)C18—C20—C21—C22175.70 (18)
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x1, y+1/2, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O20.861.942.643 (2)138.5
N2—H2N···O30.861.922.637 (2)139.4
C6—H6···O3iii0.932.533.175 (2)127.1
Symmetry code: (iii) x+1, y, z.
 

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