organic compounds
2-[(E)-(2-Morpholinoethyl)iminiomethyl]-4-nitro-1-oxocyclohexadienide
aDepartment of Physics, Faculty of Arts & Science, Ondokuz Mayıs University, TR-55139 Kurupelit–Samsun, Turkey, and bDepartment of Chemistry, Faculty of Arts & Science, Ondokuz Mayıs University, 55139 Samsun, Turkey
*Correspondence e-mail: ybingol@omu.edu.tr
The molecule of the title compound, C13H17N3O4, exists as a zwitterion, with the H atom of the phenol group being transferred to the imine N atom. The C=O, CAr—CAr and C—N bond lengths are in agreement with the oxocyclohexadienide–iminium zwitterionic form. A strong intramolecular N+—H⋯O hydrogen bond generates an S(6) ring motif. The morpholine ring adopts a chair conformation. In the crystal, molecules are linked into centrosymmetric dimers by intermolecular N—H⋯O hydrogen bonds. In addition, C—H⋯O hydrogen bonds and very weak C—H⋯π interactions are observed.
Related literature
For general background, photochromic and thermochromic characteristics of Schiff base compounds, see: Calligaris et al. (1972); Cohen et al. (1964); Hadjoudis et al. (1987); Karabıyık et al. (2008). For related structures, see: Butt et al. (1987); Petek et al. (2006); Krygowski & Stepien (2005); Santos-Contreras et al. (2009). For graph-set analysis of hydrogen bonds, see: Bernstein et al. (1995).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: X-AREA (Stoe & Cie, 2002); cell 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 (Farrugia, 1999).
Supporting information
10.1107/S1600536809026191/ci2842sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809026191/ci2842Isup2.hkl
2-Hydroxy-5-nitrobenzaldehyde (0.0535 g, 0.32 mmol) in ethanol (20 ml) was added to 2-morpholinoethylamine (0.0417 g, 0.32 mmol) in ethanol (20 ml) and the reaction mixture was stirred for 1 h under reflux. Single crystals of the title compound suitable for X-ray analysis were obtained by slow evaporation of an ethanol solution (yield % 65; m.p. 435-438 K).
Atom H1 was located in a difference map and refined freely. All other H atoms were placed in calculated positions and constrained to ride on their parent atoms, with C-H = 0.93–0.97 Å and Uiso(H) = 1.2 Ueq(C).
Data collection: X-AREA (Stoe & Cie, 2002); cell
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 (Farrugia, 1999).Fig. 1. 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 small spheres of arbitrary radii. | |
Fig. 2. A packing diagram for (I), showing O—H···O hydrogen-bonded (dashed lines) dimers. H atoms not involved in hydrogen bonding have been omitted for clarity. |
C13H17N3O4 | Z = 2 |
Mr = 279.30 | F(000) = 296 |
Triclinic, P1 | Dx = 1.372 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 5.3520 (4) Å | Cell parameters from 23053 reflections |
b = 10.8972 (9) Å | θ = 1.7–28.0° |
c = 12.4537 (9) Å | µ = 0.10 mm−1 |
α = 102.329 (7)° | T = 296 K |
β = 97.143 (6)° | Prism, orange |
γ = 104.173 (9)° | 0.75 × 0.70 × 0.40 mm |
V = 675.91 (10) Å3 |
Stoe IPDSII diffractometer | 2664 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.039 |
Graphite monochromator | θmax = 27.6°, θmin = 1.7° |
Detector resolution: 6.67 pixels mm-1 | h = −6→6 |
ω scans | k = −14→14 |
11340 measured reflections | l = −16→16 |
3094 independent reflections |
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)] = 0.040 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.110 | w = 1/[σ2(Fo2) + (0.0512P)2 + 0.1309P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max = 0.001 |
3094 reflections | Δρmax = 0.26 e Å−3 |
186 parameters | Δρmin = −0.17 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.077 (7) |
C13H17N3O4 | γ = 104.173 (9)° |
Mr = 279.30 | V = 675.91 (10) Å3 |
Triclinic, P1 | Z = 2 |
a = 5.3520 (4) Å | Mo Kα radiation |
b = 10.8972 (9) Å | µ = 0.10 mm−1 |
c = 12.4537 (9) Å | T = 296 K |
α = 102.329 (7)° | 0.75 × 0.70 × 0.40 mm |
β = 97.143 (6)° |
Stoe IPDSII diffractometer | 2664 reflections with I > 2σ(I) |
11340 measured reflections | Rint = 0.039 |
3094 independent reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.110 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | Δρmax = 0.26 e Å−3 |
3094 reflections | Δρmin = −0.17 e Å−3 |
186 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 | ||
C1 | 0.4611 (2) | 0.77887 (11) | 0.53094 (9) | 0.0335 (2) | |
C2 | 0.6439 (2) | 0.90243 (11) | 0.56526 (9) | 0.0341 (2) | |
H2 | 0.7896 | 0.9204 | 0.5315 | 0.041* | |
C3 | 0.6067 (2) | 0.99713 (10) | 0.64924 (9) | 0.0348 (3) | |
C4 | 0.3899 (3) | 0.97257 (12) | 0.70256 (10) | 0.0396 (3) | |
H4 | 0.3692 | 1.0377 | 0.7597 | 0.048* | |
C5 | 0.2112 (3) | 0.85348 (12) | 0.67033 (11) | 0.0426 (3) | |
H5 | 0.0698 | 0.8382 | 0.7069 | 0.051* | |
C6 | 0.2318 (2) | 0.74989 (11) | 0.58183 (10) | 0.0363 (3) | |
C7 | 0.5074 (2) | 0.68324 (11) | 0.44412 (9) | 0.0358 (3) | |
H7 | 0.6566 | 0.7074 | 0.4138 | 0.043* | |
C8 | 0.4146 (3) | 0.46932 (12) | 0.31724 (10) | 0.0430 (3) | |
H8A | 0.3937 | 0.3878 | 0.3393 | 0.052* | |
H8B | 0.5956 | 0.5004 | 0.3093 | 0.052* | |
C9 | 0.2370 (3) | 0.44450 (12) | 0.20590 (10) | 0.0437 (3) | |
H9A | 0.0572 | 0.4050 | 0.2113 | 0.052* | |
H9B | 0.2453 | 0.5268 | 0.1865 | 0.052* | |
C10 | 0.2038 (3) | 0.36092 (15) | 0.00679 (11) | 0.0513 (3) | |
H10A | 0.2527 | 0.4500 | −0.0009 | 0.062* | |
H10B | 0.0140 | 0.3307 | −0.0047 | 0.062* | |
C11 | 0.3025 (3) | 0.27445 (17) | −0.07913 (12) | 0.0640 (4) | |
H11A | 0.2304 | 0.2783 | −0.1534 | 0.077* | |
H11B | 0.4920 | 0.3062 | −0.0681 | 0.077* | |
C12 | 0.3364 (4) | 0.13651 (16) | 0.03730 (15) | 0.0665 (5) | |
H12A | 0.5264 | 0.1645 | 0.0487 | 0.080* | |
H12B | 0.2834 | 0.0467 | 0.0429 | 0.080* | |
C13 | 0.2450 (3) | 0.22200 (13) | 0.12725 (12) | 0.0504 (3) | |
H13A | 0.0561 | 0.1904 | 0.1194 | 0.060* | |
H13B | 0.3244 | 0.2177 | 0.2002 | 0.060* | |
N1 | 0.7884 (2) | 1.12600 (10) | 0.68031 (9) | 0.0410 (3) | |
N2 | 0.3567 (2) | 0.56554 (9) | 0.40467 (8) | 0.0378 (2) | |
N3 | 0.3171 (2) | 0.35764 (10) | 0.11888 (8) | 0.0422 (3) | |
O1 | 0.06162 (19) | 0.64042 (9) | 0.55030 (9) | 0.0513 (3) | |
O2 | 0.7384 (2) | 1.21314 (9) | 0.74731 (9) | 0.0600 (3) | |
O3 | 0.9854 (2) | 1.14568 (9) | 0.63771 (9) | 0.0549 (3) | |
O4 | 0.2302 (3) | 0.14272 (12) | −0.07115 (9) | 0.0727 (4) | |
H1 | 0.214 (4) | 0.5433 (18) | 0.4335 (15) | 0.065 (5)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0382 (6) | 0.0302 (5) | 0.0305 (5) | 0.0089 (4) | 0.0086 (4) | 0.0041 (4) |
C2 | 0.0370 (6) | 0.0324 (5) | 0.0316 (5) | 0.0083 (4) | 0.0096 (4) | 0.0055 (4) |
C3 | 0.0410 (6) | 0.0286 (5) | 0.0310 (5) | 0.0073 (4) | 0.0048 (4) | 0.0035 (4) |
C4 | 0.0493 (7) | 0.0363 (6) | 0.0335 (6) | 0.0162 (5) | 0.0120 (5) | 0.0020 (4) |
C5 | 0.0450 (7) | 0.0419 (6) | 0.0422 (6) | 0.0125 (5) | 0.0198 (5) | 0.0065 (5) |
C6 | 0.0388 (6) | 0.0319 (5) | 0.0372 (6) | 0.0085 (4) | 0.0102 (5) | 0.0063 (4) |
C7 | 0.0398 (6) | 0.0336 (5) | 0.0323 (5) | 0.0088 (5) | 0.0098 (4) | 0.0049 (4) |
C8 | 0.0508 (7) | 0.0361 (6) | 0.0374 (6) | 0.0151 (5) | 0.0086 (5) | −0.0038 (5) |
C9 | 0.0545 (7) | 0.0391 (6) | 0.0375 (6) | 0.0195 (5) | 0.0105 (5) | 0.0008 (5) |
C10 | 0.0532 (8) | 0.0582 (8) | 0.0358 (7) | 0.0119 (6) | 0.0063 (6) | 0.0030 (6) |
C11 | 0.0646 (10) | 0.0736 (10) | 0.0367 (7) | 0.0046 (8) | 0.0132 (6) | −0.0071 (7) |
C12 | 0.0776 (11) | 0.0501 (8) | 0.0648 (10) | 0.0231 (8) | 0.0203 (8) | −0.0105 (7) |
C13 | 0.0625 (9) | 0.0409 (7) | 0.0457 (7) | 0.0180 (6) | 0.0147 (6) | −0.0003 (5) |
N1 | 0.0491 (6) | 0.0311 (5) | 0.0371 (5) | 0.0070 (4) | 0.0045 (4) | 0.0030 (4) |
N2 | 0.0443 (6) | 0.0317 (5) | 0.0331 (5) | 0.0083 (4) | 0.0105 (4) | −0.0002 (4) |
N3 | 0.0497 (6) | 0.0406 (5) | 0.0324 (5) | 0.0146 (5) | 0.0088 (4) | −0.0020 (4) |
O1 | 0.0483 (5) | 0.0358 (5) | 0.0617 (6) | −0.0002 (4) | 0.0219 (4) | 0.0025 (4) |
O2 | 0.0719 (7) | 0.0337 (5) | 0.0622 (6) | 0.0106 (4) | 0.0133 (5) | −0.0092 (4) |
O3 | 0.0556 (6) | 0.0417 (5) | 0.0564 (6) | −0.0031 (4) | 0.0169 (5) | 0.0047 (4) |
O4 | 0.0816 (8) | 0.0612 (7) | 0.0526 (6) | 0.0055 (6) | 0.0197 (6) | −0.0207 (5) |
C1—C2 | 1.3994 (16) | C9—H9A | 0.97 |
C1—C7 | 1.4241 (15) | C9—H9B | 0.97 |
C1—C6 | 1.4478 (16) | C10—N3 | 1.4625 (17) |
C2—C3 | 1.3748 (15) | C10—C11 | 1.505 (2) |
C2—H2 | 0.93 | C10—H10A | 0.97 |
C3—C4 | 1.4051 (17) | C10—H10B | 0.97 |
C3—N1 | 1.4398 (15) | C11—O4 | 1.421 (2) |
C4—C5 | 1.3543 (18) | C11—H11A | 0.97 |
C4—H4 | 0.93 | C11—H11B | 0.97 |
C5—C6 | 1.4357 (16) | C12—O4 | 1.421 (2) |
C5—H5 | 0.93 | C12—C13 | 1.5086 (19) |
C6—O1 | 1.2594 (14) | C12—H12A | 0.97 |
C7—N2 | 1.2894 (15) | C12—H12B | 0.97 |
C7—H7 | 0.93 | C13—N3 | 1.4632 (18) |
C8—N2 | 1.4615 (14) | C13—H13A | 0.97 |
C8—C9 | 1.5117 (18) | C13—H13B | 0.97 |
C8—H8A | 0.97 | N1—O2 | 1.2293 (14) |
C8—H8B | 0.97 | N1—O3 | 1.2315 (14) |
C9—N3 | 1.4596 (15) | N2—H1 | 0.887 (19) |
C2—C1—C7 | 117.84 (10) | N3—C10—H10A | 109.8 |
C2—C1—C6 | 120.88 (10) | C11—C10—H10A | 109.8 |
C7—C1—C6 | 121.27 (10) | N3—C10—H10B | 109.8 |
C3—C2—C1 | 119.54 (10) | C11—C10—H10B | 109.8 |
C3—C2—H2 | 120.2 | H10A—C10—H10B | 108.2 |
C1—C2—H2 | 120.2 | O4—C11—C10 | 111.17 (13) |
C2—C3—C4 | 121.54 (10) | O4—C11—H11A | 109.4 |
C2—C3—N1 | 119.24 (10) | C10—C11—H11A | 109.4 |
C4—C3—N1 | 119.18 (10) | O4—C11—H11B | 109.4 |
C5—C4—C3 | 119.65 (11) | C10—C11—H11B | 109.4 |
C5—C4—H4 | 120.2 | H11A—C11—H11B | 108.0 |
C3—C4—H4 | 120.2 | O4—C12—C13 | 111.48 (14) |
C4—C5—C6 | 122.50 (11) | O4—C12—H12A | 109.3 |
C4—C5—H5 | 118.8 | C13—C12—H12A | 109.3 |
C6—C5—H5 | 118.8 | O4—C12—H12B | 109.3 |
O1—C6—C5 | 122.23 (11) | C13—C12—H12B | 109.3 |
O1—C6—C1 | 121.91 (10) | H12A—C12—H12B | 108.0 |
C5—C6—C1 | 115.86 (10) | N3—C13—C12 | 110.35 (13) |
N2—C7—C1 | 124.56 (11) | N3—C13—H13A | 109.6 |
N2—C7—H7 | 117.7 | C12—C13—H13A | 109.6 |
C1—C7—H7 | 117.7 | N3—C13—H13B | 109.6 |
N2—C8—C9 | 111.99 (10) | C12—C13—H13B | 109.6 |
N2—C8—H8A | 109.2 | H13A—C13—H13B | 108.1 |
C9—C8—H8A | 109.2 | O2—N1—O3 | 122.35 (11) |
N2—C8—H8B | 109.2 | O2—N1—C3 | 118.53 (11) |
C9—C8—H8B | 109.2 | O3—N1—C3 | 119.11 (10) |
H8A—C8—H8B | 107.9 | C7—N2—C8 | 122.84 (11) |
N3—C9—C8 | 110.22 (10) | C7—N2—H1 | 117.3 (12) |
N3—C9—H9A | 109.6 | C8—N2—H1 | 119.8 (12) |
C8—C9—H9A | 109.6 | C9—N3—C10 | 111.82 (10) |
N3—C9—H9B | 109.6 | C9—N3—C13 | 112.22 (10) |
C8—C9—H9B | 109.6 | C10—N3—C13 | 108.56 (11) |
H9A—C9—H9B | 108.1 | C12—O4—C11 | 109.63 (11) |
N3—C10—C11 | 109.46 (13) | ||
C7—C1—C2—C3 | −179.68 (10) | N3—C10—C11—O4 | 60.36 (17) |
C6—C1—C2—C3 | 0.69 (17) | O4—C12—C13—N3 | −57.64 (18) |
C1—C2—C3—C4 | 0.62 (18) | C2—C3—N1—O2 | 172.71 (11) |
C1—C2—C3—N1 | −176.92 (10) | C4—C3—N1—O2 | −4.89 (17) |
C2—C3—C4—C5 | −0.61 (18) | C2—C3—N1—O3 | −6.09 (17) |
N1—C3—C4—C5 | 176.93 (11) | C4—C3—N1—O3 | 176.31 (11) |
C3—C4—C5—C6 | −0.7 (2) | C1—C7—N2—C8 | −178.52 (11) |
C4—C5—C6—O1 | −178.16 (12) | C9—C8—N2—C7 | −106.90 (14) |
C4—C5—C6—C1 | 1.93 (19) | C8—C9—N3—C10 | −163.51 (11) |
C2—C1—C6—O1 | 178.21 (11) | C8—C9—N3—C13 | 74.22 (14) |
C7—C1—C6—O1 | −1.41 (18) | C11—C10—N3—C9 | 177.47 (12) |
C2—C1—C6—C5 | −1.89 (17) | C11—C10—N3—C13 | −58.19 (15) |
C7—C1—C6—C5 | 178.49 (11) | C12—C13—N3—C9 | −178.84 (12) |
C2—C1—C7—N2 | 179.62 (11) | C12—C13—N3—C10 | 57.05 (16) |
C6—C1—C7—N2 | −0.75 (18) | C13—C12—O4—C11 | 57.82 (18) |
N2—C8—C9—N3 | 174.64 (11) | C10—C11—O4—C12 | −59.34 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H1···O1 | 0.89 (2) | 1.99 (2) | 2.6760 (14) | 133 (2) |
N2—H1···O1i | 0.89 (2) | 2.24 (2) | 2.9587 (14) | 138 (2) |
C4—H4···O4ii | 0.93 | 2.47 | 3.3547 (16) | 160 |
C7—H7···O3iii | 0.93 | 2.43 | 3.3020 (15) | 157 |
C13—H13B···Cg2iv | 0.97 | 2.99 | 3.9254 | 162 |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) x, y+1, z+1; (iii) −x+2, −y+2, −z+1; (iv) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C13H17N3O4 |
Mr | 279.30 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 296 |
a, b, c (Å) | 5.3520 (4), 10.8972 (9), 12.4537 (9) |
α, β, γ (°) | 102.329 (7), 97.143 (6), 104.173 (9) |
V (Å3) | 675.91 (10) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.75 × 0.70 × 0.40 |
Data collection | |
Diffractometer | Stoe IPDSII diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11340, 3094, 2664 |
Rint | 0.039 |
(sin θ/λ)max (Å−1) | 0.652 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.110, 1.06 |
No. of reflections | 3094 |
No. of parameters | 186 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.26, −0.17 |
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 (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H1···O1 | 0.89 (2) | 1.99 (2) | 2.6760 (14) | 133 (2) |
N2—H1···O1i | 0.89 (2) | 2.24 (2) | 2.9587 (14) | 138 (2) |
C4—H4···O4ii | 0.93 | 2.47 | 3.3547 (16) | 160 |
C7—H7···O3iii | 0.93 | 2.43 | 3.3020 (15) | 157 |
C13—H13B···Cg2iv | 0.97 | 2.9908 | 3.9254 | 162.14 |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) x, y+1, z+1; (iii) −x+2, −y+2, −z+1; (iv) −x+1, −y+1, −z+1. |
Acknowledgements
The authors acknowledge the Faculty of Arts and Sciences of Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDSII diffractometer (purchased under grant No. F279 of the University Research Fund).
References
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Schiff bases have been extensively used as ligands in the field of coordination chemistry (Calligaris et al., 1972). Schiff base compounds can be classified by their photochromic and thermochromic characteristics (Cohen et al. 1964). These properties result from proton transfer from the hydroxyl O atom to the imine N atom (Hadjoudis et al., 1987). Schiff bases exhibit two well-known tautomeric forms viz. OH and NH tautomers, and they also exist in zwitterionic form (Karabıyık et al., 2008). Our investigations show that compund (I) exists in a zwitterionic form.
The molecular structure of (I) is shown in Fig.1. The C1—C7 [1.4241 (15) Å], C7═N2 [1.2894 (15) Å] and N2—C8 [1.4615 (14) Å] bond lengths agree with the corresponding distances in (E)-2-methoxy-6-[(2- morpholinoethylimino)methyl]phenolate [1.425 (2), 1.287 (2) and 1.464 (2) Å; Petek et al., 2006]. The bonds lengths in the C1-C6 benzene ring show clear alternation in the delocalized C2-C5 portion. The nitro group is tilted out of the mean plane of adjacent ring by 7.02 (3)°, whereas the C3—N1 distance of 1.4398 (15) Å is in the characteristic range suggesting limited conjugation with the ring. Thus, the whole geometry is in the agreement with the predominace of the oxocyclohexadienide-iminum zwitterion bonding scheme (see scheme) (Krygowski & Stepien, 2005; Santos-Contreras et al., 2009), in close agreement with the reported configurations of p-nitrophenolates of alkali metal cations (Butt et al., 1987). The morpholine ring adopts a chair conformation. An intramolecular N—H···O hydrogen bond generates an S(6) ring motif (Bernstein et al., 1995).
In the crystal structure of (I), the molecules form centrosymmetric dimers connected by intermolecular N—H···O hydrogen bonds (Fig. 2). In addition, C—H···O hydrogen bonds and very weak C—H···π interactions between C13-H13B group and C1-C6 benzene ring are observed (Table 1).