Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536805027546/ob6563sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536805027546/ob6563Isup2.hkl |
CCDC reference: 287674
Key indicators
- Single-crystal X-ray study
- T = 100 K
- Mean (C-C) = 0.003 Å
- R factor = 0.046
- wR factor = 0.111
- Data-to-parameter ratio = 10.5
checkCIF/PLATON results
No syntax errors found
Alert level B PLAT480_ALERT_4_B Long H...A H-Bond Reported H13 .. CG2 .. 3.26 Ang.
Alert level C PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical . ? PLAT414_ALERT_2_C Short Intra D-H..H-X H3 .. H16 .. 1.92 Ang. PLAT480_ALERT_4_C Long H...A H-Bond Reported H13 .. CG1 .. 3.12 Ang. PLAT480_ALERT_4_C Long H...A H-Bond Reported H14 .. CG2 .. 3.03 Ang. PLAT481_ALERT_4_C Long D...A H-Bond Reported C13 .. CG1 .. 4.01 Ang.
0 ALERT level A = In general: serious problem 1 ALERT level B = Potentially serious problem 5 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 0 ALERT type 3 Indicator that the structure quality may be low 4 ALERT type 4 Improvement, methodology, query or suggestion
Compound (I) was prepared as described in the literature (Odabaşoğlu, Albayrak, Büyükgüngör & Lönneche, 2003), using 1-aminonaphthalene and 2,3-dihydroxybenzaldehyde as starting materials. Crystals of (I) were obtained from a tetrahydrofuran solution by slow evaporation (yield 88%, m.p. 508–510 K).
All H atoms were located in difference Fourier maps and refined isotropically, except for atom H2 bonded to atom O2, which was refined with the O—H bond distance restrained to 0.82 (2) Å, and with Uiso(H) = 1.5Uiso(O). The C—H distances are in the range 0.95 (2)–1.02 (3) Å.
Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1998).
C17H13NO2 | F(000) = 552 |
Mr = 263.28 | Dx = 1.409 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 11212 reflections |
a = 7.3546 (5) Å | θ = 1.7–26.1° |
b = 23.7901 (17) Å | µ = 0.09 mm−1 |
c = 7.4919 (5) Å | T = 100 K |
β = 108.738 (6)° | Plate, red |
V = 1241.35 (15) Å3 | 0.19 × 0.13 × 0.05 mm |
Z = 4 |
Stoe IPDS-2 diffractometer | 2435 independent reflections |
Radiation source: fine-focus sealed tube | 1668 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.063 |
Detector resolution: 6.67 pixels mm-1 | θmax = 26.1°, θmin = 1.7° |
ω scans | h = −8→9 |
Absorption correction: integration (X-RED; Stoe & Cie, 2002) | k = −29→29 |
Tmin = 0.987, Tmax = 0.996 | l = −9→9 |
11951 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)] = 0.046 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.111 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.0602P)2] where P = (Fo2 + 2Fc2)/3 |
2435 reflections | (Δ/σ)max < 0.001 |
232 parameters | Δρmax = 0.16 e Å−3 |
1 restraint | Δρmin = −0.25 e Å−3 |
C17H13NO2 | V = 1241.35 (15) Å3 |
Mr = 263.28 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.3546 (5) Å | µ = 0.09 mm−1 |
b = 23.7901 (17) Å | T = 100 K |
c = 7.4919 (5) Å | 0.19 × 0.13 × 0.05 mm |
β = 108.738 (6)° |
Stoe IPDS-2 diffractometer | 2435 independent reflections |
Absorption correction: integration (X-RED; Stoe & Cie, 2002) | 1668 reflections with I > 2σ(I) |
Tmin = 0.987, Tmax = 0.996 | Rint = 0.063 |
11951 measured reflections |
R[F2 > 2σ(F2)] = 0.046 | 1 restraint |
wR(F2) = 0.111 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.16 e Å−3 |
2435 reflections | Δρmin = −0.25 e Å−3 |
232 parameters |
Experimental. 245 frames, detector distance = 130 mm |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.3656 (3) | 0.50975 (8) | 0.2339 (3) | 0.0241 (4) | |
C2 | 0.4898 (3) | 0.46940 (7) | 0.1997 (3) | 0.0243 (4) | |
C3 | 0.6931 (3) | 0.47626 (7) | 0.2757 (2) | 0.0236 (4) | |
C4 | 0.8087 (3) | 0.43510 (8) | 0.2239 (2) | 0.0250 (4) | |
C5 | 0.7277 (3) | 0.39035 (8) | 0.1123 (3) | 0.0268 (4) | |
C6 | 0.5266 (3) | 0.38369 (8) | 0.0411 (3) | 0.0275 (4) | |
C7 | 0.4103 (3) | 0.42222 (8) | 0.0831 (3) | 0.0263 (4) | |
C8 | 0.3211 (3) | 0.60023 (8) | 0.3694 (2) | 0.0244 (4) | |
C9 | 0.1240 (3) | 0.60006 (8) | 0.3004 (3) | 0.0289 (4) | |
C10 | 0.0190 (3) | 0.64574 (8) | 0.3363 (3) | 0.0309 (5) | |
C11 | 0.1118 (3) | 0.69048 (9) | 0.4410 (3) | 0.0311 (5) | |
C12 | 0.3145 (3) | 0.69158 (8) | 0.5164 (3) | 0.0267 (4) | |
C13 | 0.4130 (3) | 0.73688 (8) | 0.6298 (3) | 0.0306 (5) | |
C14 | 0.6078 (3) | 0.73732 (8) | 0.7035 (3) | 0.0306 (5) | |
C15 | 0.7163 (3) | 0.69277 (8) | 0.6661 (3) | 0.0291 (4) | |
C16 | 0.6266 (3) | 0.64809 (8) | 0.5569 (3) | 0.0269 (4) | |
C17 | 0.4240 (3) | 0.64604 (8) | 0.4794 (2) | 0.0248 (4) | |
N1 | 0.4310 (2) | 0.55513 (6) | 0.3355 (2) | 0.0242 (4) | |
O1 | 0.77225 (19) | 0.51768 (5) | 0.38424 (18) | 0.0277 (3) | |
O2 | 1.0043 (2) | 0.44126 (6) | 0.28678 (19) | 0.0301 (3) | |
H1 | 0.225 (3) | 0.5059 (9) | 0.173 (3) | 0.033 (6)* | |
H2 | 1.038 (4) | 0.4627 (9) | 0.387 (3) | 0.047* | |
H3 | 0.575 (4) | 0.5570 (11) | 0.383 (3) | 0.050 (7)* | |
H5 | 0.814 (3) | 0.3624 (10) | 0.086 (3) | 0.038 (6)* | |
H6 | 0.475 (3) | 0.3512 (9) | −0.037 (3) | 0.028 (5)* | |
H7 | 0.268 (3) | 0.4190 (9) | 0.032 (3) | 0.029 (5)* | |
H9 | 0.056 (3) | 0.5679 (10) | 0.223 (3) | 0.039 (6)* | |
H10 | −0.127 (4) | 0.6463 (9) | 0.283 (3) | 0.038 (6)* | |
H11 | 0.039 (3) | 0.7212 (10) | 0.473 (3) | 0.039 (6)* | |
H13 | 0.337 (3) | 0.7664 (9) | 0.655 (3) | 0.028 (5)* | |
H14 | 0.676 (4) | 0.7696 (10) | 0.786 (3) | 0.048 (7)* | |
H15 | 0.861 (4) | 0.6934 (10) | 0.724 (3) | 0.040 (6)* | |
H16 | 0.707 (3) | 0.6190 (9) | 0.534 (3) | 0.031 (5)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0237 (11) | 0.0257 (9) | 0.0218 (9) | −0.0011 (8) | 0.0057 (8) | 0.0027 (7) |
C2 | 0.0247 (10) | 0.0252 (10) | 0.0229 (9) | 0.0004 (7) | 0.0076 (8) | 0.0030 (7) |
C3 | 0.0241 (10) | 0.0221 (9) | 0.0235 (9) | −0.0012 (7) | 0.0063 (8) | 0.0021 (7) |
C4 | 0.0204 (10) | 0.0273 (10) | 0.0266 (9) | −0.0003 (7) | 0.0067 (8) | 0.0040 (7) |
C5 | 0.0266 (11) | 0.0265 (10) | 0.0269 (9) | 0.0030 (8) | 0.0082 (8) | 0.0018 (8) |
C6 | 0.0320 (12) | 0.0253 (10) | 0.0242 (9) | −0.0020 (8) | 0.0076 (8) | −0.0007 (8) |
C7 | 0.0242 (11) | 0.0272 (9) | 0.0257 (10) | −0.0031 (8) | 0.0056 (8) | −0.0001 (7) |
C8 | 0.0238 (11) | 0.0259 (9) | 0.0244 (9) | 0.0031 (8) | 0.0088 (8) | 0.0033 (7) |
C9 | 0.0271 (11) | 0.0294 (10) | 0.0297 (10) | 0.0005 (8) | 0.0083 (8) | −0.0001 (8) |
C10 | 0.0247 (11) | 0.0338 (11) | 0.0344 (10) | 0.0054 (8) | 0.0099 (9) | 0.0015 (8) |
C11 | 0.0321 (12) | 0.0312 (10) | 0.0329 (11) | 0.0047 (9) | 0.0143 (9) | 0.0027 (8) |
C12 | 0.0299 (11) | 0.0252 (9) | 0.0275 (10) | 0.0023 (8) | 0.0125 (8) | 0.0040 (8) |
C13 | 0.0381 (12) | 0.0263 (10) | 0.0303 (10) | 0.0009 (9) | 0.0151 (9) | 0.0003 (8) |
C14 | 0.0365 (12) | 0.0271 (10) | 0.0286 (10) | −0.0035 (9) | 0.0112 (9) | −0.0003 (8) |
C15 | 0.0313 (12) | 0.0281 (10) | 0.0284 (10) | −0.0035 (8) | 0.0104 (9) | 0.0002 (8) |
C16 | 0.0276 (11) | 0.0275 (10) | 0.0270 (9) | 0.0002 (8) | 0.0108 (8) | 0.0031 (8) |
C17 | 0.0274 (11) | 0.0247 (9) | 0.0235 (9) | 0.0007 (7) | 0.0099 (8) | 0.0034 (7) |
N1 | 0.0227 (9) | 0.0245 (8) | 0.0252 (8) | 0.0008 (6) | 0.0073 (7) | 0.0011 (6) |
O1 | 0.0242 (7) | 0.0260 (7) | 0.0302 (7) | −0.0021 (6) | 0.0049 (6) | −0.0036 (5) |
O2 | 0.0222 (7) | 0.0351 (8) | 0.0321 (7) | 0.0003 (6) | 0.0077 (6) | −0.0051 (6) |
C1—N1 | 1.320 (2) | C9—H9 | 0.99 (2) |
C1—C2 | 1.404 (3) | C10—C11 | 1.367 (3) |
C1—H1 | 0.99 (2) | C10—H10 | 1.02 (2) |
C2—C7 | 1.427 (3) | C11—C12 | 1.415 (3) |
C2—C3 | 1.429 (3) | C11—H11 | 0.98 (2) |
C3—O1 | 1.291 (2) | C12—C13 | 1.419 (3) |
C3—C4 | 1.429 (3) | C12—C17 | 1.430 (3) |
C4—C5 | 1.367 (3) | C13—C14 | 1.360 (3) |
C4—O2 | 1.370 (2) | C13—H13 | 0.95 (2) |
C5—C6 | 1.411 (3) | C14—C15 | 1.408 (3) |
C5—H5 | 0.98 (2) | C14—H14 | 1.01 (3) |
C6—C7 | 1.357 (3) | C15—C16 | 1.374 (3) |
C6—H6 | 0.97 (2) | C15—H15 | 1.01 (3) |
C7—H7 | 1.00 (2) | C16—C17 | 1.415 (3) |
C8—C9 | 1.374 (3) | C16—H16 | 0.96 (2) |
C8—N1 | 1.415 (2) | N1—H3 | 1.00 (3) |
C8—C17 | 1.428 (3) | O2—H2 | 0.876 (17) |
C9—C10 | 1.408 (3) | ||
N1—C1—C2 | 121.77 (18) | C11—C10—H10 | 118.9 (13) |
N1—C1—H1 | 118.1 (12) | C9—C10—H10 | 120.6 (13) |
C2—C1—H1 | 120.0 (12) | C10—C11—C12 | 120.74 (19) |
C1—C2—C7 | 119.15 (18) | C10—C11—H11 | 120.8 (14) |
C1—C2—C3 | 120.57 (17) | C12—C11—H11 | 118.3 (14) |
C7—C2—C3 | 120.25 (17) | C11—C12—C13 | 121.56 (18) |
O1—C3—C2 | 122.70 (17) | C11—C12—C17 | 119.72 (18) |
O1—C3—C4 | 120.45 (17) | C13—C12—C17 | 118.73 (18) |
C2—C3—C4 | 116.85 (16) | C14—C13—C12 | 121.19 (19) |
C5—C4—O2 | 119.79 (17) | C14—C13—H13 | 121.3 (13) |
C5—C4—C3 | 121.28 (17) | C12—C13—H13 | 117.4 (13) |
O2—C4—C3 | 118.93 (16) | C13—C14—C15 | 120.26 (19) |
C4—C5—C6 | 121.14 (18) | C13—C14—H14 | 120.2 (14) |
C4—C5—H5 | 118.0 (14) | C15—C14—H14 | 119.5 (14) |
C6—C5—H5 | 120.9 (14) | C16—C15—C14 | 120.4 (2) |
C7—C6—C5 | 119.89 (18) | C16—C15—H15 | 120.3 (13) |
C7—C6—H6 | 121.8 (13) | C14—C15—H15 | 119.3 (13) |
C5—C6—H6 | 118.3 (13) | C15—C16—C17 | 120.82 (19) |
C6—C7—C2 | 120.56 (18) | C15—C16—H16 | 117.2 (14) |
C6—C7—H7 | 121.5 (12) | C17—C16—H16 | 122.0 (13) |
C2—C7—H7 | 117.9 (12) | C16—C17—C8 | 123.80 (17) |
C9—C8—N1 | 121.67 (18) | C16—C17—C12 | 118.59 (17) |
C9—C8—C17 | 121.28 (18) | C8—C17—C12 | 117.58 (17) |
N1—C8—C17 | 117.05 (17) | C1—N1—C8 | 126.91 (17) |
C8—C9—C10 | 120.20 (19) | C1—N1—H3 | 113.0 (15) |
C8—C9—H9 | 119.6 (14) | C8—N1—H3 | 120.0 (15) |
C10—C9—H9 | 120.2 (14) | C4—O2—H2 | 109.3 (17) |
C11—C10—C9 | 120.5 (2) | ||
N1—C1—C2—C7 | −177.77 (17) | C10—C11—C12—C13 | −178.21 (18) |
N1—C1—C2—C3 | 0.2 (3) | C10—C11—C12—C17 | 1.4 (3) |
C1—C2—C3—O1 | 3.1 (3) | C11—C12—C13—C14 | 179.27 (18) |
C7—C2—C3—O1 | −178.91 (16) | C17—C12—C13—C14 | −0.4 (3) |
C1—C2—C3—C4 | −176.07 (16) | C12—C13—C14—C15 | 0.9 (3) |
C7—C2—C3—C4 | 1.9 (3) | C13—C14—C15—C16 | −0.9 (3) |
O1—C3—C4—C5 | 178.65 (17) | C14—C15—C16—C17 | 0.3 (3) |
C2—C3—C4—C5 | −2.2 (3) | C15—C16—C17—C8 | −178.12 (18) |
O1—C3—C4—O2 | −1.9 (2) | C15—C16—C17—C12 | 0.2 (3) |
C2—C3—C4—O2 | 177.23 (16) | C9—C8—C17—C16 | 178.84 (17) |
O2—C4—C5—C6 | −178.22 (16) | N1—C8—C17—C16 | −1.0 (3) |
C3—C4—C5—C6 | 1.2 (3) | C9—C8—C17—C12 | 0.5 (3) |
C4—C5—C6—C7 | 0.1 (3) | N1—C8—C17—C12 | −179.30 (15) |
C5—C6—C7—C2 | −0.3 (3) | C11—C12—C17—C16 | −179.83 (17) |
C1—C2—C7—C6 | 177.30 (17) | C13—C12—C17—C16 | −0.2 (2) |
C3—C2—C7—C6 | −0.7 (3) | C11—C12—C17—C8 | −1.4 (2) |
N1—C8—C9—C10 | −179.80 (17) | C13—C12—C17—C8 | 178.25 (17) |
C17—C8—C9—C10 | 0.4 (3) | C2—C1—N1—C8 | 175.65 (16) |
C8—C9—C10—C11 | −0.4 (3) | C9—C8—N1—C1 | 2.2 (3) |
C9—C10—C11—C12 | −0.5 (3) | C17—C8—N1—C1 | −177.96 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H3···O1 | 1.00 (3) | 1.73 (3) | 2.576 (2) | 140 (2) |
O2—H2···O1i | 0.88 (2) | 1.89 (2) | 2.670 (2) | 148 (2) |
C13—H13···Cg1ii | 0.95 (2) | 3.12 (2) | 4.008 (2) | 155 (2) |
C13—H13···Cg2ii | 0.95 (2) | 3.26 (2) | 3.705 (2) | 111 (2) |
C14—H14···Cg2ii | 1.01 (3) | 3.03 (3) | 3.604 (2) | 117 (2) |
Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) x, −y−1/2, z−3/2. |
Experimental details
Crystal data | |
Chemical formula | C17H13NO2 |
Mr | 263.28 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 7.3546 (5), 23.7901 (17), 7.4919 (5) |
β (°) | 108.738 (6) |
V (Å3) | 1241.35 (15) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.19 × 0.13 × 0.05 |
Data collection | |
Diffractometer | Stoe IPDS2 diffractometer |
Absorption correction | Integration (X-RED; Stoe & Cie, 2002) |
Tmin, Tmax | 0.987, 0.996 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11951, 2435, 1668 |
Rint | 0.063 |
(sin θ/λ)max (Å−1) | 0.618 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.046, 0.111, 1.00 |
No. of reflections | 2435 |
No. of parameters | 232 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.16, −0.25 |
Computer programs: X-AREA (Stoe & Cie, 2002), X-AREA, X-RED (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1998).
C1—N1 | 1.320 (2) | C4—C5 | 1.367 (3) |
C1—C2 | 1.404 (3) | C4—O2 | 1.370 (2) |
C2—C7 | 1.427 (3) | C5—C6 | 1.411 (3) |
C2—C3 | 1.429 (3) | C6—C7 | 1.357 (3) |
C3—O1 | 1.291 (2) | C8—N1 | 1.415 (2) |
C3—C4 | 1.429 (3) | ||
N1—C1—C2 | 121.77 (18) | O1—C3—C2 | 122.70 (17) |
C1—C2—C7 | 119.15 (18) | O1—C3—C4 | 120.45 (17) |
C1—C2—C3 | 120.57 (17) | C1—N1—C8 | 126.91 (17) |
N1—C1—C2—C7 | −177.77 (17) | C2—C1—N1—C8 | 175.65 (16) |
N1—C1—C2—C3 | 0.2 (3) | C9—C8—N1—C1 | 2.2 (3) |
C1—C2—C3—O1 | 3.1 (3) | C17—C8—N1—C1 | −177.96 (17) |
N1—C8—C17—C16 | −1.0 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H3···O1 | 1.00 (3) | 1.73 (3) | 2.576 (2) | 140 (2) |
O2—H2···O1i | 0.88 (2) | 1.89 (2) | 2.670 (2) | 148 (2) |
C13—H13···Cg1ii | 0.95 (2) | 3.12 (2) | 4.008 (2) | 155 (2) |
C13—H13···Cg2ii | 0.95 (2) | 3.26 (2) | 3.705 (2) | 111 (2) |
C14—H14···Cg2ii | 1.01 (3) | 3.03 (3) | 3.604 (2) | 117 (2) |
Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) x, −y−1/2, z−3/2. |
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Schiff bases are reported to show a variety of biological activities, such as antibacterial (Pandeya et al., 1999; El-masry et al., 2000; Kabeer et al., 2001), anticancer (Phatak et al., 2000; Desai et al., 2001), antifungal (Singh & Dash, 1988; More et al., 2001) and herbicidal (Samadhiya & Halve, 2001). Schiff base compounds show photochromism and thermochromism in the solid state by proton transfer from the hydroxyl O atom to the imine N atom (Hadjoudis et al., 1987). Schiff bases display two possible tautomeric forms, namely phenol–imine (O—H···N) and keto–amine (N—H···O) forms. o-Hydroxy Schiff bases have been previously observed in the keto form (Ünver, Kabak et al., 2002; Odabaşoğlu, Albayrak, Büyükgüngör & Goesmann, 2003) and in the enol form (Ünver, Yıldız et al., 2002; Karadayı et al., 2003).
In the title compound, (I), the keto–amine tautomer is favoured over the phenol–imine form (Fig. 1). The C3—O1 and C1—N1 bond lengths verify the keto–amine form of (I). These distances agree with the corresponding distances in 3-[(2-oxo-1-naphthylidene)methyleamino]benzoic acid [1.290 (2) and 1.319 (3) Å; Pavlovic & Sosa, 2000] and 2-{[tris(hydroxymethyl)methyl]aminomethylene}cyclohexa-3,5-dien-1(2H)-one [1.3025 (16) and 1.2952 (18) Å; Odabaşoğlu, Albayrak, Büyükgüngör & Lönneche, 2003], which also show the keto–amine tautomeric form. In the crystal of N-(2-pyridyl)-2-oxo-1-naphthylidenemethylamine, there are two independent molecules which constitute a tautomeric pair, with C—O bond distances of 1.263 (4) and 1.279 (4) Å in the keto–amine and enol–imine forms, respectively (Nazır et al., 2000).
Schiff base compounds can be classified by their photochromic and thermochromic chracteristics (Cohen et al., 1964). On the basis of some thermochromic and photochromic Schiff base compounds, it was proposed that molecules exhibiting thermochromism are planar, while those exhibiting photochromism are nonplanar (Moustakali et al., 1978), and planarity of the molecule makes it possible for the proton to transfer through the hydrogen bond in the ground state with a low energy requirement (Bregman, Leiserowitz & Schmidt, 1964; Bregman, Leiserowitz & Osaki, 1964). The molecule of (I) is almost planar: the angle between the rings of atoms C2–C7 and C8–C12/C17 is 5.87 (8)°.
The intra- and intermolecular hydrogen bonding in (I) is shown in Fig. 2 and geometric details of the hydrogen bonds are given in Table 2. Atom H3 bonded to N1 forms a strong intramolecular hydrogen bond with atom O1, as observed in similar compounds (Odabaşoğlu, Albayrak, Büyükgüngör & Goesmann, 2003; Odabaşoğlu, Albayrak, Büyükgüngör & Lönneche, 2004). The molecules are linked by O—H···O hydrogen bonds to form dimers, and further linked by C—H···π interactions (Table 2), forming a three-dimensional network. In Table 2, Cg1 and Cg2 are the centroids of the C8–C17 and C12–C17 rings, respectively.