organic compounds
E)-4-hydroxy-3-{1-[(4-hydroxyphenyl)imino]ethyl}-6-methyl-2H-pyran-2-one
of (aLaboratoire de Physicochimie Analytique et Cristallochimie de Matériaux, Organométalliques et Biomoléculaires, Université de Constantine 1, 25000 Constantine, Algeria, bLaboratoire de Génie Mécanique et Matériaux, Faculté de Technologie, Université 20 Aout 1955, 21000 Skikda, Algeria, and cInstitut Jean Lamour UMR 7198, Parc de Saurupt, CS 14234 F 54042 Nancy, France
*Correspondence e-mail: boufas_sihem@yahoo.fr
In the title Schiff base, C14H13NO4, which adopts the phenol–imine tautomeric form, the dihedral angle between the planes of the benzene and heterocyclic (r.m.s. deviation = 0.037 Å) rings is 53.31 (11)°. An intramolecular O—H⋯N hydrogen bond closes an S(6) ring. In the crystal, molecules are linked by O—H⋯O hydrogen bonds to generate C(11) chains propagating in the [010] direction. A weak C—H⋯O link is also observed, leading to the formation of R55(32) rings extending parallel to the (101) plane.
Keywords: crystal structure; hydroxy Schiff base; pyran-2-one; phenol–imine tautomer; hydrogen bonding; proton-transfer processes.
CCDC reference: 1410367
1. Related literature
For photochromic and thermochromic properties of hydroxy et al. (1993); Hadjoudis et al. (2004). For potential materials for optical memory and switch devices, see: Zhao et al. (2007). For proton-transfer processes, see: Lussier et al. (1987). For Schiff base structures, see: Djedouani et al. (2007, 2008). For Schiff base bond lengths and angles, see: Girija & Begum (2004); Girija et al. (2004); Bai & Jing (2007).
see: Garnovskii2. Experimental
2.1. Crystal data
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2.3. Refinement
|
|
Data collection: COLLECT (Nonius, 2002); cell DENZO-SMN (Otwinowski & Minor, 1997); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: OLEX2.refine (Dolomanov et al., 2009); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 2012) and PARST (Nardelli, 1995).
Supporting information
CCDC reference: 1410367
https://doi.org/10.1107/S2056989015012840/hb7460sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015012840/hb7460Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989015012840/hb7460Isup3.cml
Compound (I) was prepared by refluxing a mixture of a solution containing dehydroacetic acid (0.01 mmol) and para-4-aminophenol (0.01 mmol) in ethanol (40 ml). The reaction mixture was stirred for 2 h under reflux and left to cool. Yellow crystals grew after a few days.
C—H and O—H hydrogen atoms were placed in calculated positions and refined as riding atoms with C—H distances of 0.93 Å with Uiso(H) = 1.2Ueq(C) and O—H distances of 0.82 Å, with Uiso(H) = 1.2Ueq(N).
The methyl H atoms were constrained to an ideal geometry (C—H = 0.96 Å) with Uiso(H) = 1.2Ueq(C), but were allowed to rotate freely about the C—C bonds.
Hydroxy
have been extensively studied due to their biological, photochromic and thermochromic properties (Garnovskii et al., 1993; Hadjoudis et al., 2004). They are potential materials for optical memory and switch devices (Zhao et al., 2007). Proton transfer in these compounds forms the basis for an explanation of the mechanisms of various biological processes where proton transfer is the rate-determining step (Lussier et al., 1987). In general, O-hydroxy exhibit two possible tautomeric forms, the phenol-imine (or benzenoid) and ketoamine (or quinoid) forms. Depending on the tautomers, two types of intra-molecular hydrogen bonds are possible: O—H···N in benzenoid and N—H···O in quinoid tautomers.As part of our ongoing studies of
(Djedouani et al., 2007, 2008), we now describe the synthesis and the structure of the title compound, which takes the form phenol-imine and complete a six-membered pseudocycle via an intramolecular O—H····O hydrogen bond.The dehydroacetic acid ring and phenyl ring are almost planer with r.m.s deviation for the mean plane are 0.0260 and 0.0027 respectively. The dihedral angle between the two rings is 53.30 (0.05) °. The two torsional angles τ1 (N1—C5—C14—C4) and τ2 (C5—N1—C1—C6) defining the confirmation of the molecule.
The N1—C5 distance of 1.324 (2) Å agree with similar bond in related compounds (Girija & Begum, 2004; Girija et al. 2004), slightly longer than a typical C=N bond (1.283 (4) Å) (Bai & Jing, 2007); but much shorter than the single carbon-nitrogen bond (Table. 1), N1—C1=1.432 (3) Å because of the resonance. The carbon-carbon bond connecting the phenol and imine groups exhibits intermediate distances between a single and a double bond and agree well with those observed in other
The C5—N1—C14 and C14—C5—N1 bond angle of 117.70 (2)° and 117.47 () ° respectively in the Schiff base ligand are smaller than typical hexagonal of 120°. This is due to the effect of substitution on O of pyron & OH of the DHA ring.In the crystal, molecules are aligned head to foot along b axis, in columns along to [0 0 1] axis and the structure is stabilized by an O—H···O hydrogen bond and another weak C—H···O interaction, leading to the formation of R55(32) rings extending parallel to the (101) plane (Fig. 2, Table.1).
For photochromic and thermochromic properties of hydroxy
see: Garnovskii et al. (1993); Hadjoudis et al. (2004). For potential materials for optical memory and switch devices, see: Zhao et al. (2007). For proton-transfer processes, see: Lussier et al. (1987). For Schiff base structures, see: Djedouani et al. (2007, 2008) For Schiff base bond lengths and angles, see: Girija & Begum (2004); Girija et al. (2004); Bai & Jing (2007).Data collection: COLLECT (Nonius, 2002); cell
DENZO-SMN (Otwinowski & Minor, 1997); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: olex2.refine (Dolomanov et al., 2009); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 2012) and PARST (Nardelli, 1995).C14H13NO4 | F(000) = 544.3271 |
Mr = 259.26 | Dx = 1.391 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 0 reflections |
a = 7.8730 (5) Å | θ = 2.9–27.5° |
b = 11.7930 (8) Å | µ = 0.10 mm−1 |
c = 13.5330 (8) Å | T = 293 K |
β = 99.896 (2)° | Block, yellow |
V = 1237.79 (14) Å3 | 0.10 × 0.06 × 0.03 mm |
Z = 4 |
Nonius KappaCCD diffractometer | 2582 independent reflections |
Radiation source: Enraf–Nonius FR590 | 2061 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
Detector resolution: 9 pixels mm-1 | θmax = 26.7°, θmin = 2.3° |
CCD rotation images, thin slices scans | h = −9→9 |
Absorption correction: multi-scan (SADABS; Sheldrick, 2002) | k = −14→14 |
Tmin = 0.875, Tmax = 0.947 | l = −17→17 |
17976 measured reflections |
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)] = 0.047 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.148 | All H-atom parameters refined |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0655P)2 + 0.6848P] where P = (Fo2 + 2Fc2)/3 |
2582 reflections | (Δ/σ)max = 0.005 |
173 parameters | Δρmax = 0.54 e Å−3 |
0 restraints | Δρmin = −0.38 e Å−3 |
C14H13NO4 | V = 1237.79 (14) Å3 |
Mr = 259.26 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.8730 (5) Å | µ = 0.10 mm−1 |
b = 11.7930 (8) Å | T = 293 K |
c = 13.5330 (8) Å | 0.10 × 0.06 × 0.03 mm |
β = 99.896 (2)° |
Nonius KappaCCD diffractometer | 2582 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2002) | 2061 reflections with I > 2σ(I) |
Tmin = 0.875, Tmax = 0.947 | Rint = 0.026 |
17976 measured reflections |
R[F2 > 2σ(F2)] = 0.047 | 0 restraints |
wR(F2) = 0.148 | All H-atom parameters refined |
S = 1.07 | Δρmax = 0.54 e Å−3 |
2582 reflections | Δρmin = −0.38 e Å−3 |
173 parameters |
x | y | z | Uiso*/Ueq | ||
O1 | 0.6637 (2) | −0.08723 (12) | 0.50633 (10) | 0.0520 (4) | |
H1 | 0.6696 (2) | −0.05535 (12) | 0.45317 (10) | 0.0779 (6)* | |
O2 | 0.4993 (2) | 0.21003 (13) | −0.00201 (10) | 0.0543 (4) | |
H2 | 0.4624 (2) | 0.27519 (13) | −0.00450 (10) | 0.0815 (7)* | |
O3 | 1.0343 (3) | 0.20593 (17) | 0.65333 (13) | 0.0814 (7) | |
O4 | 0.92760 (19) | 0.08216 (12) | 0.74439 (9) | 0.0443 (4) | |
C1 | 0.6821 (3) | 0.11371 (17) | 0.29043 (13) | 0.0390 (4) | |
C2 | 0.7568 (3) | −0.07161 (18) | 0.67874 (15) | 0.0444 (5) | |
H2a | 0.7031 (3) | −0.13959 (18) | 0.68968 (15) | 0.0533 (6)* | |
C3 | 0.6279 (3) | 0.07382 (18) | 0.11415 (14) | 0.0433 (5) | |
H3 | 0.6333 (3) | 0.02421 (18) | 0.06136 (14) | 0.0520 (6)* | |
C4 | 0.7488 (3) | −0.03156 (16) | 0.57810 (14) | 0.0391 (4) | |
C5 | 0.8305 (3) | 0.12191 (16) | 0.46720 (14) | 0.0382 (4) | |
C6 | 0.6138 (3) | 0.22135 (17) | 0.27136 (14) | 0.0416 (5) | |
H6 | 0.6089 (3) | 0.27092 (17) | 0.32425 (14) | 0.0499 (6)* | |
C7 | 0.5531 (3) | 0.25514 (17) | 0.17428 (14) | 0.0416 (5) | |
H7 | 0.5074 (3) | 0.32751 (17) | 0.16191 (14) | 0.0499 (6)* | |
C8 | 0.8390 (3) | −0.01396 (17) | 0.75665 (14) | 0.0407 (5) | |
C9 | 0.9259 (3) | 0.22691 (19) | 0.44950 (16) | 0.0489 (5) | |
H9a | 0.9215 (18) | 0.2372 (8) | 0.37874 (17) | 0.0733 (8)* | |
H9b | 0.8738 (13) | 0.2909 (3) | 0.4764 (11) | 0.0733 (8)* | |
H9c | 1.0438 (6) | 0.2203 (6) | 0.4820 (10) | 0.0733 (8)* | |
C10 | 0.5598 (3) | 0.18172 (17) | 0.09476 (13) | 0.0389 (4) | |
C11 | 0.9398 (3) | 0.12553 (18) | 0.65006 (15) | 0.0454 (5) | |
C12 | 0.8492 (3) | −0.0416 (2) | 0.86465 (15) | 0.0554 (6) | |
H12a | 0.9678 (4) | −0.0434 (15) | 0.8967 (3) | 0.0831 (9)* | |
H12b | 0.789 (2) | 0.0151 (9) | 0.8959 (3) | 0.0831 (9)* | |
H12c | 0.797 (2) | −0.1144 (7) | 0.87109 (15) | 0.0831 (9)* | |
C13 | 0.6877 (3) | 0.03998 (17) | 0.21150 (15) | 0.0419 (5) | |
H13 | 0.7319 (3) | −0.03271 (17) | 0.22414 (15) | 0.0502 (6)* | |
C14 | 0.8397 (2) | 0.07122 (16) | 0.56378 (13) | 0.0368 (4) | |
N1 | 0.7321 (2) | 0.07168 (14) | 0.39048 (12) | 0.0434 (4) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0748 (11) | 0.0408 (8) | 0.0347 (7) | −0.0120 (7) | −0.0066 (7) | 0.0022 (6) |
O2 | 0.0822 (11) | 0.0507 (9) | 0.0265 (7) | 0.0122 (8) | −0.0009 (7) | 0.0018 (6) |
O3 | 0.1131 (16) | 0.0775 (13) | 0.0444 (9) | −0.0536 (12) | −0.0125 (9) | 0.0064 (9) |
O4 | 0.0563 (9) | 0.0434 (8) | 0.0295 (7) | −0.0021 (6) | −0.0029 (6) | −0.0003 (6) |
C1 | 0.0454 (11) | 0.0404 (10) | 0.0286 (9) | −0.0016 (8) | −0.0009 (7) | 0.0027 (8) |
C2 | 0.0565 (13) | 0.0373 (10) | 0.0383 (10) | −0.0024 (9) | 0.0051 (9) | 0.0042 (8) |
C3 | 0.0508 (12) | 0.0445 (11) | 0.0329 (10) | 0.0055 (9) | 0.0021 (8) | −0.0065 (8) |
C4 | 0.0466 (11) | 0.0347 (10) | 0.0332 (9) | 0.0032 (8) | −0.0009 (8) | −0.0006 (8) |
C5 | 0.0431 (10) | 0.0367 (10) | 0.0329 (9) | 0.0046 (8) | 0.0012 (8) | 0.0004 (8) |
C6 | 0.0557 (12) | 0.0394 (10) | 0.0290 (9) | 0.0000 (9) | 0.0052 (8) | −0.0029 (8) |
C7 | 0.0532 (12) | 0.0359 (10) | 0.0343 (10) | 0.0040 (9) | 0.0036 (8) | 0.0028 (8) |
C8 | 0.0475 (11) | 0.0389 (10) | 0.0346 (10) | 0.0077 (8) | 0.0046 (8) | 0.0027 (8) |
C9 | 0.0536 (13) | 0.0506 (12) | 0.0397 (11) | −0.0060 (10) | 0.0007 (9) | 0.0079 (9) |
C10 | 0.0451 (11) | 0.0425 (11) | 0.0275 (9) | 0.0004 (8) | 0.0018 (7) | 0.0032 (8) |
C11 | 0.0555 (13) | 0.0423 (11) | 0.0348 (10) | −0.0052 (10) | −0.0028 (9) | 0.0032 (8) |
C12 | 0.0773 (16) | 0.0557 (14) | 0.0329 (11) | 0.0044 (12) | 0.0088 (10) | 0.0034 (9) |
C13 | 0.0462 (11) | 0.0379 (10) | 0.0385 (10) | 0.0066 (8) | −0.0008 (8) | 0.0005 (8) |
C14 | 0.0439 (11) | 0.0336 (9) | 0.0306 (9) | 0.0029 (8) | −0.0002 (8) | 0.0021 (7) |
N1 | 0.0560 (10) | 0.0414 (9) | 0.0290 (8) | −0.0014 (8) | −0.0033 (7) | 0.0036 (7) |
O1—H1 | 0.82 | C5—C9 | 1.489 (3) |
O1—C4 | 1.265 (2) | C5—C14 | 1.428 (3) |
O2—H2 | 0.82 | C5—N1 | 1.324 (2) |
O2—C10 | 1.356 (2) | C6—H6 | 0.93 |
O3—C11 | 1.201 (3) | C6—C7 | 1.377 (3) |
O4—C8 | 1.356 (2) | C7—H7 | 0.93 |
O4—C11 | 1.394 (2) | C7—C10 | 1.389 (3) |
C1—C6 | 1.385 (3) | C8—C12 | 1.486 (3) |
C1—C13 | 1.384 (3) | C9—H9a | 0.96 |
C1—N1 | 1.432 (2) | C9—H9b | 0.96 |
C2—H2a | 0.93 | C9—H9c | 0.96 |
C2—C4 | 1.433 (3) | C11—C14 | 1.442 (3) |
C2—C8 | 1.326 (3) | C12—H12a | 0.96 |
C3—H3 | 0.93 | C12—H12b | 0.96 |
C3—C10 | 1.388 (3) | C12—H12c | 0.96 |
C3—C13 | 1.380 (3) | C13—H13 | 0.93 |
C4—C14 | 1.438 (3) | ||
C4—O1—H1 | 109.5 | C12—C8—C2 | 127.3 (2) |
C10—O2—H2 | 109.5 | H9a—C9—C5 | 109.5 |
C11—O4—C8 | 122.46 (15) | H9b—C9—C5 | 109.5 |
C13—C1—C6 | 119.66 (17) | H9b—C9—H9a | 109.5 |
N1—C1—C6 | 121.88 (17) | H9c—C9—C5 | 109.5 |
N1—C1—C13 | 118.18 (18) | H9c—C9—H9a | 109.5 |
C4—C2—H2a | 119.25 (12) | H9c—C9—H9b | 109.5 |
C8—C2—H2a | 119.25 (12) | C3—C10—O2 | 117.93 (17) |
C8—C2—C4 | 121.5 (2) | C7—C10—O2 | 122.75 (18) |
C10—C3—H3 | 119.90 (11) | C7—C10—C3 | 119.31 (17) |
C13—C3—H3 | 119.90 (12) | O4—C11—O3 | 113.30 (18) |
C13—C3—C10 | 120.19 (18) | C14—C11—O3 | 129.00 (19) |
C2—C4—O1 | 119.33 (18) | C14—C11—O4 | 117.69 (18) |
C14—C4—O1 | 122.99 (17) | H12a—C12—C8 | 109.5 |
C14—C4—C2 | 117.68 (17) | H12b—C12—C8 | 109.5 |
C14—C5—C9 | 123.23 (17) | H12b—C12—H12a | 109.5 |
N1—C5—C9 | 119.29 (17) | H12c—C12—C8 | 109.5 |
N1—C5—C14 | 117.48 (18) | H12c—C12—H12a | 109.5 |
H6—C6—C1 | 119.91 (11) | H12c—C12—H12b | 109.5 |
C7—C6—C1 | 120.17 (18) | C3—C13—C1 | 120.30 (18) |
C7—C6—H6 | 119.91 (12) | H13—C13—C1 | 119.85 (11) |
H7—C7—C6 | 119.82 (12) | H13—C13—C3 | 119.85 (12) |
C10—C7—C6 | 120.36 (18) | C5—C14—C4 | 121.89 (17) |
C10—C7—H7 | 119.82 (11) | C11—C14—C4 | 118.74 (17) |
C2—C8—O4 | 121.50 (18) | C11—C14—C5 | 119.35 (18) |
C12—C8—O4 | 111.21 (18) | C5—N1—C1 | 127.99 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.82 | 1.83 | 2.560 (2) | 147 |
O2—H2···O1i | 0.82 | 1.90 | 2.710 (2) | 169 |
C12—H12B···O3ii | 0.96 | 2.55 | 3.137 (3) | 120 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+2, y−1/2, −z+3/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.82 | 1.83 | 2.560 (2) | 147 |
O2—H2···O1i | 0.82 | 1.90 | 2.710 (2) | 169 |
C12—H12B···O3ii | 0.96 | 2.55 | 3.137 (3) | 120 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+2, y−1/2, −z+3/2. |
Acknowledgements
This work was supported by Université Constantine 1, DZ-25000, Constantine, Algeria.
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Hydroxy Schiff bases have been extensively studied due to their biological, photochromic and thermochromic properties (Garnovskii et al., 1993; Hadjoudis et al., 2004). They are potential materials for optical memory and switch devices (Zhao et al., 2007). Proton transfer in these compounds forms the basis for an explanation of the mechanisms of various biological processes where proton transfer is the rate-determining step (Lussier et al., 1987). In general, O-hydroxy Schiff bases exhibit two possible tautomeric forms, the phenol-imine (or benzenoid) and ketoamine (or quinoid) forms. Depending on the tautomers, two types of intra-molecular hydrogen bonds are possible: O—H···N in benzenoid and N—H···O in quinoid tautomers.
As part of our ongoing studies of Schiff bases (Djedouani et al., 2007, 2008), we now describe the synthesis and the structure of the title compound, which takes the form phenol-imine and complete a six-membered pseudocycle via an intramolecular O—H····O hydrogen bond.
The dehydroacetic acid ring and phenyl ring are almost planer with r.m.s deviation for the mean plane are 0.0260 and 0.0027 respectively. The dihedral angle between the two rings is 53.30 (0.05) °. The two torsional angles τ1 (N1—C5—C14—C4) and τ2 (C5—N1—C1—C6) defining the confirmation of the molecule.
The N1—C5 distance of 1.324 (2) Å agree with similar bond in related compounds (Girija & Begum, 2004; Girija et al. 2004), slightly longer than a typical C=N bond (1.283 (4) Å) (Bai & Jing, 2007); but much shorter than the single carbon-nitrogen bond (Table. 1), N1—C1=1.432 (3) Å because of the resonance. The carbon-carbon bond connecting the phenol and imine groups exhibits intermediate distances between a single and a double bond and agree well with those observed in other azomethines. The C5—N1—C14 and C14—C5—N1 bond angle of 117.70 (2)° and 117.47 () ° respectively in the Schiff base ligand are smaller than typical hexagonal of 120°. This is due to the effect of substitution on O of pyron & OH of the DHA ring.
In the crystal, molecules are aligned head to foot along b axis, in columns along to [0 0 1] axis and the structure is stabilized by an O—H···O hydrogen bond and another weak C—H···O interaction, leading to the formation of R55(32) rings extending parallel to the (101) plane (Fig. 2, Table.1).