organic compounds
Z)-3-benzyloxy-6-[(2-hydroxy-5-methylanilino)methylidene]cyclohexa-2,4-dien-1-one
of (aUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale (CHEMS), Faculté des Sciences Exactes, Département de Chimie, Université Constantine 1, Algeria
*Correspondence e-mail: king.ali@hotmail.fr
In the title Schiff base compound, C21H19NO3, the conformation about the C=C bond is Z. The N—H group and carbonyl O atom form an intramolecular N—H⋯O hydrogen bond with an S(6) ring motif. The benzyloxy ring and the 2-hydroxy-5-methylphenyl ring are inclined to the central six-membered ring by 13.68 (9) and 9.13 (8)°, respectively, and to one another by 21.95 (9)°. In the crystal, molecules are linked by O—H⋯O hydrogen bonds, forming helical chains along [010].
Keywords: crystal structure; Schiff base; azomethines.
CCDC reference: 1015522
1. Related literature
For some general background on et al. (2002); El-Masry et al. (2000); Jarrahpour & Khalili (2006); More et al. (2001); Phatak et al. (2000). For related structures, see: Akkurt et al. (2005, 2008). For pharmaceutical and industrial applications of see: Prakash & Adhikari (2011). For the effect of hydrophilicity on drug properties, see: Lin & Lu (1997).
and their various biological activities, see: Arora2. Experimental
2.1. Crystal data
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2.2. Data collection
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2.3. Refinement
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Data collection: APEX2 (Bruker, 2006); cell SAINT (Bruker, 2006); data reduction: SAINT; 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, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012).
Supporting information
CCDC reference: 1015522
10.1107/S1600536814016936/su2761sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536814016936/su2761Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536814016936/su2761Isup3.cml
A mixture of 2-amino-4-methylphenol (1 mmol) and 4-(benzyloxy)-2-hydroxybenzaldehyde (1 mmol) was heated to form a clear solution. To this a few drops of conc. HCL was added as a catalyst and the mixture was refluxed for 12 h. After cooling the solution to 80°C it was stirred for 45 min the a precipitate formed. It was filtered off and washed with ice cold ethyl acetate to give the pure title Schiff base compound as an orange solid (yield 35%). This crude product was dissolved in ethyl acetate and two spoons of
were added. The mixture was filtered over celiteµ000174 and the product was crystallized from ethyl acetate. The compound was very difficult to crystalize and only after several attempts over a period of four months were crystals suitable for X-ray finally obtained.The OH and NH H atoms, and the methine H atom were located in a difference Fourier map and freely refined. The C-bound H atoms were fixed geometrically and treated as riding atoms: C—H = 0.93 Å (aromatic) and 0.97 Å (methylene) with Uiso(H) = 1.2Ueq(C).
Data collection: APEX2 (Bruker, 2006); cell
SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); 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, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012).C21H19NO3 | Z = 4 |
Mr = 333.37 | F(000) = 704 |
Monoclinic, P21/c | Dx = 1.268 Mg m−3 |
Hall symbol: -P 2ybc | Mo Kα radiation, λ = 0.71073 Å |
a = 12.594 (5) Å | µ = 0.09 mm−1 |
b = 9.303 (5) Å | T = 293 K |
c = 14.997 (5) Å | Block, orange |
β = 96.402 (5)° | 0.03 × 0.02 × 0.01 mm |
V = 1746.1 (13) Å3 |
Bruker APEXII CCD diffractometer | 2672 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.037 |
Graphite monochromator | θmax = 30.2°, θmin = 2.6° |
phi and ω scans | h = −17→17 |
19603 measured reflections | k = −13→13 |
5148 independent reflections | l = −21→20 |
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)] = 0.050 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.158 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.01 | w = 1/[σ2(Fo2) + (0.0718P)2 + 0.1066P] where P = (Fo2 + 2Fc2)/3 |
5148 reflections | (Δ/σ)max < 0.001 |
238 parameters | Δρmax = 0.22 e Å−3 |
0 restraints | Δρmin = −0.16 e Å−3 |
C21H19NO3 | V = 1746.1 (13) Å3 |
Mr = 333.37 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 12.594 (5) Å | µ = 0.09 mm−1 |
b = 9.303 (5) Å | T = 293 K |
c = 14.997 (5) Å | 0.03 × 0.02 × 0.01 mm |
β = 96.402 (5)° |
Bruker APEXII CCD diffractometer | 2672 reflections with I > 2σ(I) |
19603 measured reflections | Rint = 0.037 |
5148 independent reflections |
R[F2 > 2σ(F2)] = 0.050 | 0 restraints |
wR(F2) = 0.158 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.01 | Δρmax = 0.22 e Å−3 |
5148 reflections | Δρmin = −0.16 e Å−3 |
238 parameters |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.00597 (9) | 0.00730 (11) | 0.29239 (8) | 0.0607 (4) | |
O2 | 0.11904 (9) | 0.35839 (11) | 0.32139 (8) | 0.0632 (4) | |
O3 | 0.35952 (9) | 0.74624 (12) | 0.39999 (9) | 0.0686 (4) | |
N1 | 0.14153 (10) | 0.12579 (13) | 0.41887 (9) | 0.0466 (4) | |
C1 | 0.10315 (13) | −0.23275 (17) | 0.52145 (11) | 0.0543 (5) | |
C2 | 0.03317 (14) | −0.29008 (17) | 0.45329 (12) | 0.0599 (6) | |
C3 | −0.00117 (13) | −0.21414 (16) | 0.37654 (11) | 0.0557 (5) | |
C4 | 0.03510 (12) | −0.07513 (15) | 0.36568 (10) | 0.0464 (5) | |
C5 | 0.10653 (11) | −0.01575 (15) | 0.43336 (10) | 0.0435 (4) | |
C6 | 0.13925 (12) | −0.09409 (16) | 0.51009 (10) | 0.0502 (5) | |
C7 | 0.21681 (12) | 0.19787 (17) | 0.46691 (11) | 0.0500 (5) | |
C8 | 0.24727 (11) | 0.33802 (16) | 0.44826 (10) | 0.0488 (5) | |
C9 | 0.19690 (11) | 0.41507 (16) | 0.37232 (11) | 0.0488 (5) | |
C10 | 0.23632 (12) | 0.55360 (16) | 0.35497 (11) | 0.0535 (5) | |
C11 | 0.31795 (12) | 0.61279 (17) | 0.41101 (11) | 0.0549 (6) | |
C12 | 0.36589 (14) | 0.53810 (18) | 0.48665 (13) | 0.0654 (6) | |
C13 | 0.33182 (13) | 0.40505 (18) | 0.50384 (12) | 0.0626 (6) | |
C14 | 0.31877 (13) | 0.82640 (18) | 0.32322 (12) | 0.0600 (6) | |
C15 | 0.37303 (14) | 0.96959 (18) | 0.32326 (12) | 0.0597 (6) | |
C16 | 0.32694 (18) | 1.0777 (2) | 0.26853 (13) | 0.0769 (8) | |
C17 | 0.3757 (2) | 1.2105 (2) | 0.26580 (14) | 0.0893 (9) | |
C18 | 0.4695 (2) | 1.2378 (2) | 0.31800 (16) | 0.0918 (10) | |
C19 | 0.51594 (18) | 1.1327 (2) | 0.37257 (18) | 0.0933 (9) | |
C20 | 0.46785 (16) | 0.9979 (2) | 0.37561 (16) | 0.0781 (8) | |
C21 | 0.13941 (16) | −0.3163 (2) | 0.60556 (13) | 0.0792 (8) | |
H1o | −0.0411 (17) | −0.044 (2) | 0.2490 (16) | 0.101 (7)* | |
H2 | 0.00830 | −0.38330 | 0.45937 | 0.0719* | |
H1n | 0.1091 (14) | 0.1794 (19) | 0.3701 (13) | 0.075 (6)* | |
H3 | −0.04862 | −0.25606 | 0.33208 | 0.0668* | |
H6 | 0.18647 | −0.05266 | 0.55491 | 0.0603* | |
H7 | 0.2525 (13) | 0.1493 (17) | 0.5192 (12) | 0.065 (5)* | |
H10 | 0.20650 | 0.60482 | 0.30510 | 0.0642* | |
H12 | 0.42068 | 0.58043 | 0.52442 | 0.0785* | |
H13 | 0.36443 | 0.35558 | 0.55341 | 0.0750* | |
H14A | 0.24242 | 0.84004 | 0.32335 | 0.0720* | |
H14B | 0.33057 | 0.77387 | 0.26933 | 0.0720* | |
H16 | 0.26261 | 1.06082 | 0.23328 | 0.0922* | |
H17 | 0.34437 | 1.28183 | 0.22815 | 0.1070* | |
H18 | 0.50154 | 1.32764 | 0.31634 | 0.1101* | |
H19 | 0.57997 | 1.15094 | 0.40792 | 0.1119* | |
H20 | 0.49987 | 0.92686 | 0.41309 | 0.0937* | |
H21A | 0.10696 | −0.40980 | 0.60202 | 0.1186* | |
H21B | 0.11862 | −0.26601 | 0.65674 | 0.1186* | |
H21C | 0.21574 | −0.32628 | 0.61143 | 0.1186* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0764 (8) | 0.0485 (6) | 0.0514 (7) | −0.0042 (5) | −0.0186 (6) | 0.0026 (5) |
O2 | 0.0626 (7) | 0.0505 (6) | 0.0687 (8) | −0.0121 (5) | −0.0277 (6) | 0.0067 (5) |
O3 | 0.0682 (7) | 0.0572 (7) | 0.0771 (9) | −0.0194 (6) | −0.0061 (6) | −0.0054 (6) |
N1 | 0.0481 (7) | 0.0460 (7) | 0.0435 (7) | 0.0016 (5) | −0.0050 (6) | −0.0001 (6) |
C1 | 0.0591 (10) | 0.0511 (9) | 0.0523 (9) | 0.0110 (7) | 0.0047 (8) | 0.0065 (7) |
C2 | 0.0691 (10) | 0.0415 (8) | 0.0684 (11) | 0.0006 (7) | 0.0041 (9) | 0.0038 (8) |
C3 | 0.0612 (10) | 0.0449 (8) | 0.0580 (10) | −0.0016 (7) | −0.0066 (8) | −0.0057 (7) |
C4 | 0.0490 (8) | 0.0436 (8) | 0.0448 (8) | 0.0055 (6) | −0.0029 (7) | −0.0017 (6) |
C5 | 0.0430 (7) | 0.0412 (7) | 0.0456 (8) | 0.0057 (6) | 0.0019 (6) | −0.0023 (6) |
C6 | 0.0502 (9) | 0.0533 (9) | 0.0457 (9) | 0.0052 (7) | −0.0014 (7) | 0.0000 (7) |
C7 | 0.0501 (9) | 0.0538 (9) | 0.0436 (9) | 0.0020 (7) | −0.0060 (7) | −0.0022 (7) |
C8 | 0.0449 (8) | 0.0508 (8) | 0.0487 (9) | −0.0029 (7) | −0.0041 (7) | −0.0059 (7) |
C9 | 0.0426 (8) | 0.0482 (8) | 0.0529 (9) | −0.0017 (6) | −0.0063 (7) | −0.0075 (7) |
C10 | 0.0517 (9) | 0.0491 (8) | 0.0569 (10) | −0.0032 (7) | −0.0069 (7) | −0.0011 (7) |
C11 | 0.0484 (9) | 0.0501 (9) | 0.0650 (11) | −0.0082 (7) | 0.0013 (8) | −0.0106 (8) |
C12 | 0.0581 (10) | 0.0642 (11) | 0.0682 (11) | −0.0130 (8) | −0.0182 (9) | −0.0096 (9) |
C13 | 0.0612 (10) | 0.0634 (10) | 0.0576 (10) | −0.0062 (8) | −0.0178 (8) | −0.0039 (8) |
C14 | 0.0588 (10) | 0.0554 (9) | 0.0659 (11) | −0.0070 (8) | 0.0075 (9) | −0.0090 (8) |
C15 | 0.0650 (11) | 0.0543 (9) | 0.0630 (11) | −0.0093 (8) | 0.0210 (9) | −0.0150 (8) |
C16 | 0.1016 (15) | 0.0646 (12) | 0.0650 (12) | −0.0107 (11) | 0.0122 (11) | −0.0092 (10) |
C17 | 0.140 (2) | 0.0627 (12) | 0.0685 (14) | −0.0114 (13) | 0.0257 (14) | −0.0049 (10) |
C18 | 0.127 (2) | 0.0675 (13) | 0.0879 (17) | −0.0338 (13) | 0.0433 (15) | −0.0139 (12) |
C19 | 0.0841 (15) | 0.0798 (15) | 0.1170 (19) | −0.0316 (12) | 0.0161 (14) | −0.0185 (14) |
C20 | 0.0707 (12) | 0.0616 (11) | 0.1026 (16) | −0.0153 (9) | 0.0123 (11) | −0.0092 (10) |
C21 | 0.0904 (14) | 0.0737 (12) | 0.0710 (13) | 0.0068 (10) | −0.0014 (11) | 0.0239 (10) |
O1—C4 | 1.357 (2) | C15—C20 | 1.379 (3) |
O2—C9 | 1.287 (2) | C15—C16 | 1.384 (3) |
O3—C11 | 1.365 (2) | C16—C17 | 1.382 (3) |
O3—C14 | 1.419 (2) | C17—C18 | 1.366 (4) |
O1—H1o | 0.96 (2) | C18—C19 | 1.364 (3) |
N1—C5 | 1.413 (2) | C19—C20 | 1.396 (3) |
N1—C7 | 1.310 (2) | C2—H2 | 0.9300 |
N1—H1n | 0.940 (19) | C3—H3 | 0.9300 |
C1—C6 | 1.385 (2) | C6—H6 | 0.9300 |
C1—C21 | 1.508 (3) | C7—H7 | 0.971 (17) |
C1—C2 | 1.380 (3) | C10—H10 | 0.9300 |
C2—C3 | 1.378 (2) | C12—H12 | 0.9300 |
C3—C4 | 1.387 (2) | C13—H13 | 0.9300 |
C4—C5 | 1.393 (2) | C14—H14A | 0.9700 |
C5—C6 | 1.385 (2) | C14—H14B | 0.9700 |
C7—C8 | 1.396 (2) | C16—H16 | 0.9300 |
C8—C13 | 1.421 (2) | C17—H17 | 0.9300 |
C8—C9 | 1.433 (2) | C18—H18 | 0.9300 |
C9—C10 | 1.416 (2) | C19—H19 | 0.9300 |
C10—C11 | 1.369 (2) | C20—H20 | 0.9300 |
C11—C12 | 1.408 (3) | C21—H21A | 0.9600 |
C12—C13 | 1.344 (2) | C21—H21B | 0.9600 |
C14—C15 | 1.497 (3) | C21—H21C | 0.9600 |
C11—O3—C14 | 117.87 (13) | C18—C19—C20 | 120.3 (2) |
C4—O1—H1o | 111.1 (13) | C15—C20—C19 | 120.28 (19) |
C5—N1—C7 | 127.71 (13) | C1—C2—H2 | 119.00 |
C5—N1—H1n | 119.9 (11) | C3—C2—H2 | 119.00 |
C7—N1—H1n | 112.4 (11) | C2—C3—H3 | 120.00 |
C2—C1—C6 | 117.40 (15) | C4—C3—H3 | 120.00 |
C2—C1—C21 | 121.94 (15) | C1—C6—H6 | 119.00 |
C6—C1—C21 | 120.67 (15) | C5—C6—H6 | 119.00 |
C1—C2—C3 | 122.37 (15) | N1—C7—H7 | 116.6 (10) |
C2—C3—C4 | 119.94 (15) | C8—C7—H7 | 118.9 (10) |
C3—C4—C5 | 118.58 (14) | C9—C10—H10 | 120.00 |
O1—C4—C3 | 124.00 (14) | C11—C10—H10 | 120.00 |
O1—C4—C5 | 117.41 (13) | C11—C12—H12 | 120.00 |
N1—C5—C4 | 116.40 (13) | C13—C12—H12 | 120.00 |
N1—C5—C6 | 123.29 (13) | C8—C13—H13 | 119.00 |
C4—C5—C6 | 120.31 (13) | C12—C13—H13 | 119.00 |
C1—C6—C5 | 121.40 (14) | O3—C14—H14A | 110.00 |
N1—C7—C8 | 124.48 (15) | O3—C14—H14B | 110.00 |
C9—C8—C13 | 118.89 (14) | C15—C14—H14A | 110.00 |
C7—C8—C9 | 121.29 (14) | C15—C14—H14B | 110.00 |
C7—C8—C13 | 119.80 (14) | H14A—C14—H14B | 108.00 |
O2—C9—C8 | 120.49 (13) | C15—C16—H16 | 120.00 |
O2—C9—C10 | 121.57 (14) | C17—C16—H16 | 120.00 |
C8—C9—C10 | 117.93 (14) | C16—C17—H17 | 120.00 |
C9—C10—C11 | 120.54 (15) | C18—C17—H17 | 120.00 |
C10—C11—C12 | 121.43 (15) | C17—C18—H18 | 120.00 |
O3—C11—C12 | 114.26 (14) | C19—C18—H18 | 120.00 |
O3—C11—C10 | 124.31 (15) | C18—C19—H19 | 120.00 |
C11—C12—C13 | 119.45 (16) | C20—C19—H19 | 120.00 |
C8—C13—C12 | 121.72 (16) | C15—C20—H20 | 120.00 |
O3—C14—C15 | 110.09 (14) | C19—C20—H20 | 120.00 |
C14—C15—C16 | 119.02 (16) | C1—C21—H21A | 109.00 |
C14—C15—C20 | 122.43 (16) | C1—C21—H21B | 109.00 |
C16—C15—C20 | 118.55 (17) | C1—C21—H21C | 109.00 |
C15—C16—C17 | 120.6 (2) | H21A—C21—H21B | 109.00 |
C16—C17—C18 | 120.52 (19) | H21A—C21—H21C | 109.00 |
C17—C18—C19 | 119.73 (19) | H21B—C21—H21C | 109.00 |
C14—O3—C11—C10 | −3.0 (2) | C7—C8—C9—C10 | −176.46 (14) |
C14—O3—C11—C12 | 177.39 (14) | C13—C8—C9—O2 | −178.95 (14) |
C11—O3—C14—C15 | 179.43 (14) | C13—C8—C9—C10 | 1.8 (2) |
C7—N1—C5—C4 | −171.50 (15) | C7—C8—C13—C12 | 177.89 (16) |
C7—N1—C5—C6 | 8.9 (2) | C9—C8—C13—C12 | −0.4 (2) |
C5—N1—C7—C8 | 179.88 (14) | O2—C9—C10—C11 | 178.81 (15) |
C6—C1—C2—C3 | −0.4 (3) | C8—C9—C10—C11 | −1.9 (2) |
C21—C1—C2—C3 | 179.41 (16) | C9—C10—C11—O3 | −178.96 (14) |
C2—C1—C6—C5 | 0.0 (2) | C9—C10—C11—C12 | 0.7 (2) |
C21—C1—C6—C5 | −179.84 (15) | O3—C11—C12—C13 | −179.54 (15) |
C1—C2—C3—C4 | 0.3 (3) | C10—C11—C12—C13 | 0.8 (3) |
C2—C3—C4—O1 | 179.74 (15) | C11—C12—C13—C8 | −0.9 (3) |
C2—C3—C4—C5 | 0.3 (2) | O3—C14—C15—C16 | −163.21 (16) |
O1—C4—C5—N1 | 0.2 (2) | O3—C14—C15—C20 | 17.1 (2) |
O1—C4—C5—C6 | 179.81 (14) | C14—C15—C16—C17 | −178.97 (18) |
C3—C4—C5—N1 | 179.66 (14) | C20—C15—C16—C17 | 0.7 (3) |
C3—C4—C5—C6 | −0.7 (2) | C14—C15—C20—C19 | 179.30 (19) |
N1—C5—C6—C1 | −179.83 (14) | C16—C15—C20—C19 | −0.4 (3) |
C4—C5—C6—C1 | 0.6 (2) | C15—C16—C17—C18 | −0.9 (3) |
N1—C7—C8—C9 | −0.4 (2) | C16—C17—C18—C19 | 0.7 (4) |
N1—C7—C8—C13 | −178.58 (15) | C17—C18—C19—C20 | −0.3 (4) |
C7—C8—C9—O2 | 2.8 (2) | C18—C19—C20—C15 | 0.2 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1n···O2 | 0.94 (2) | 1.83 (2) | 2.609 (2) | 138.7 (16) |
O1—H1o···O2i | 0.96 (2) | 1.63 (2) | 2.590 (2) | 176.1 (17) |
Symmetry code: (i) −x, y−1/2, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1n···O2 | 0.94 (2) | 1.83 (2) | 2.609 (2) | 138.7 (16) |
O1—H1o···O2i | 0.96 (2) | 1.63 (2) | 2.590 (2) | 176.1 (17) |
Symmetry code: (i) −x, y−1/2, −z+1/2. |
Acknowledgements
The authors thank the MESRS (Algeria) for financial support. We also thank all researchers of the CHEMS Research Unit, University of Constantine 1, Algeria, for their valuable assistance.
References
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