(E)-2-Eth­oxy-6-[(4-nitro­phen­yl)imino­meth­yl]phenol

The title compound, C₁₅H₁₄N₂O₄, exists as an enol–imine tautomer, in which a strong intra­molecular O—H...N hydrogen bond is formed. This work verifies the preference for the enol–imine tautomeric form in the solid state.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.035
• wR factor = 0.068
• Data-to-parameter ratio = 14.2

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    N1     -   C4      ..       7.23 su

Alert level C
PLAT026_ALERT_3_C Ratio Observed / Unique Reflections too Low ....         48 Perc.
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_C Check the Reported _diffrn_ambient_temperature .        293 K

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   3 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
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (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, 1999).

(E)-2-Ethoxy-6-[(4-nitrophenyl)iminomethyl]phenol

Crystal data

C15H14N2O4	F(000) = 1200
Mr = 286.28	Dx = 1.391 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 11318 reflections
a = 27.883 (2) Å	θ = 1.5–26.1°
b = 7.1237 (7) Å	µ = 0.10 mm^−1
c = 14.7975 (10) Å	T = 293 K
β = 111.524 (4)°	Prism, dark red
V = 2734.2 (4) Å^3	0.42 × 0.30 × 0.11 mm
Z = 8

Data collection

Stoe IPDS 2 diffractometer	2693 independent reflections
Radiation source: fine-focus sealed tube	1289 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.071
Detector resolution: 6.67 pixels mm^-1	θmax = 26.0°, θmin = 1.6°
rotation scans	h = −34→34
Absorption correction: integration X-RED32 (Stoe & Cie, 2002)	k = −8→8
Tmin = 0.966, Tmax = 0.989	l = −18→17
16558 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.069	H-atom parameters constrained
S = 0.81	w = 1/[σ^2(Fo^2) + (0.075P)^2] where P = (Fo^2 + 2Fc^2)/3
2693 reflections	(Δ/σ)max < 0.001
190 parameters	Δρmax = 0.08 e Å^−3
28 restraints	Δρmin = −0.14 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
N2	0.19145 (5)	0.01499 (17)	0.46671 (9)	0.0541 (3)
O4	0.08969 (4)	0.23344 (16)	0.66700 (8)	0.0698 (3)
C4	0.30980 (6)	−0.1273 (2)	0.37268 (13)	0.0582 (4)
C1	0.23027 (6)	−0.0365 (2)	0.43092 (11)	0.0514 (4)
C13	0.11459 (6)	0.1315 (2)	0.54012 (12)	0.0524 (4)
O3	0.16196 (4)	0.10675 (15)	0.60865 (7)	0.0647 (3)
H33	0.1818	0.0709	0.5829	0.097*
C7	0.14488 (6)	0.0428 (2)	0.40868 (12)	0.0552 (4)
H7	0.1369	0.0269	0.3424	0.066*
C8	0.10437 (6)	0.0979 (2)	0.44210 (11)	0.0502 (4)
C12	0.07507 (6)	0.1970 (2)	0.56943 (12)	0.0560 (4)
C11	0.02645 (6)	0.2202 (2)	0.50197 (13)	0.0638 (5)
H11	0.0002	0.2614	0.5216	0.077*
N1	0.35282 (7)	−0.1742 (2)	0.34188 (15)	0.0774 (5)
O1	0.34245 (6)	−0.2107 (2)	0.25592 (12)	0.1027 (5)
C6	0.22042 (6)	−0.1233 (2)	0.34157 (11)	0.0617 (4)
H2	0.1867	−0.1510	0.3015	0.074*
O2	0.39643 (5)	−0.1736 (2)	0.40282 (12)	0.1021 (5)
C2	0.28053 (6)	0.0002 (2)	0.49074 (12)	0.0576 (4)
H6	0.2872	0.0559	0.5510	0.069*
C5	0.26057 (7)	−0.1681 (2)	0.31272 (12)	0.0646 (5)
H3	0.2543	−0.2256	0.2530	0.078*
C9	0.05420 (6)	0.1236 (2)	0.37502 (12)	0.0613 (4)
H13	0.0469	0.0999	0.3095	0.074*
C3	0.32096 (6)	−0.0450 (2)	0.46198 (13)	0.0618 (5)
H5	0.3549	−0.0203	0.5021	0.074*
C10	0.01584 (6)	0.1830 (2)	0.40447 (13)	0.0670 (5)
H12	−0.0174	0.1986	0.3593	0.080*
C15	0.07949 (7)	0.3888 (2)	0.80025 (12)	0.0752 (5)
H15A	0.0555	0.4539	0.8220	0.113*
H15B	0.1077	0.4707	0.8051	0.113*
H15C	0.0924	0.2800	0.8401	0.113*
C14	0.05272 (7)	0.3293 (2)	0.69640 (12)	0.0685 (5)
H14A	0.0241	0.2467	0.6906	0.082*
H14B	0.0394	0.4383	0.6555	0.082*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N2	0.0539 (8)	0.0602 (8)	0.0524 (8)	0.0010 (7)	0.0243 (7)	0.0011 (6)
O4	0.0651 (8)	0.0940 (8)	0.0551 (7)	0.0220 (6)	0.0277 (6)	−0.0012 (6)
C4	0.0603 (12)	0.0553 (10)	0.0701 (12)	0.0049 (8)	0.0371 (10)	0.0057 (9)
C1	0.0529 (11)	0.0525 (10)	0.0528 (11)	−0.0005 (8)	0.0240 (9)	0.0044 (8)
C13	0.0472 (10)	0.0586 (10)	0.0511 (10)	0.0030 (8)	0.0175 (9)	0.0064 (8)
O3	0.0545 (7)	0.0896 (8)	0.0499 (7)	0.0129 (6)	0.0190 (6)	0.0009 (6)
C7	0.0618 (11)	0.0574 (10)	0.0505 (10)	0.0001 (8)	0.0254 (9)	0.0038 (8)
C8	0.0518 (10)	0.0541 (9)	0.0474 (10)	0.0014 (7)	0.0213 (9)	0.0039 (8)
C12	0.0551 (11)	0.0631 (10)	0.0516 (11)	0.0050 (8)	0.0217 (9)	0.0039 (9)
C11	0.0533 (11)	0.0756 (12)	0.0662 (12)	0.0102 (9)	0.0265 (10)	0.0022 (9)
N1	0.0757 (12)	0.0687 (10)	0.1041 (14)	0.0020 (9)	0.0521 (12)	0.0055 (10)
O1	0.1157 (12)	0.1109 (12)	0.1132 (12)	−0.0056 (9)	0.0795 (11)	−0.0205 (10)
C6	0.0559 (11)	0.0757 (11)	0.0537 (11)	0.0016 (9)	0.0204 (9)	−0.0062 (9)
O2	0.0640 (9)	0.1167 (12)	0.1357 (13)	0.0112 (8)	0.0486 (10)	0.0047 (10)
C2	0.0589 (11)	0.0617 (10)	0.0533 (10)	−0.0021 (9)	0.0218 (9)	−0.0038 (8)
C5	0.0671 (12)	0.0730 (11)	0.0602 (11)	0.0043 (10)	0.0310 (10)	−0.0054 (9)
C9	0.0583 (11)	0.0689 (11)	0.0531 (10)	0.0030 (9)	0.0162 (9)	0.0017 (8)
C3	0.0522 (11)	0.0645 (11)	0.0687 (12)	−0.0024 (8)	0.0223 (9)	0.0029 (9)
C10	0.0535 (11)	0.0802 (12)	0.0612 (12)	0.0099 (9)	0.0138 (9)	0.0030 (10)
C15	0.0869 (13)	0.0782 (12)	0.0733 (13)	0.0012 (10)	0.0444 (11)	−0.0095 (10)
C14	0.0707 (11)	0.0747 (11)	0.0723 (12)	0.0106 (10)	0.0409 (10)	0.0002 (10)

Geometric parameters (Å, º)

N2—C7	1.2825 (17)	C11—H11	0.9300
N2—C1	1.4168 (18)	N1—O2	1.2197 (18)
O4—C12	1.3734 (18)	N1—O1	1.2246 (18)
O4—C14	1.4310 (17)	C6—C5	1.374 (2)
C4—C5	1.365 (2)	C6—H2	0.9300
C4—C3	1.373 (2)	C2—C3	1.381 (2)
C4—N1	1.469 (2)	C2—H6	0.9300
C1—C2	1.380 (2)	C5—H3	0.9300
C1—C6	1.393 (2)	C9—C10	1.362 (2)
C13—O3	1.3496 (16)	C9—H13	0.9300
C13—C8	1.393 (2)	C3—H5	0.9300
C13—C12	1.404 (2)	C10—H12	0.9300
O3—H33	0.8200	C15—C14	1.502 (2)
C7—C8	1.443 (2)	C15—H15A	0.9600
C7—H7	0.9300	C15—H15B	0.9600
C8—C9	1.399 (2)	C15—H15C	0.9600
C12—C11	1.367 (2)	C14—H14A	0.9700
C11—C10	1.388 (2)	C14—H14B	0.9700
C7—N2—C1	120.97 (14)	C1—C6—H2	120.0
C12—O4—C14	116.15 (13)	C1—C2—C3	120.62 (16)
C5—C4—C3	122.38 (16)	C1—C2—H6	119.7
C5—C4—N1	119.38 (17)	C3—C2—H6	119.7
C3—C4—N1	118.23 (17)	C4—C5—C6	119.24 (16)
C2—C1—C6	119.57 (15)	C4—C5—H3	120.4
C2—C1—N2	116.50 (14)	C6—C5—H3	120.4
C6—C1—N2	123.93 (15)	C10—C9—C8	120.80 (16)
O3—C13—C8	121.99 (14)	C10—C9—H13	119.6
O3—C13—C12	118.31 (14)	C8—C9—H13	119.6
C8—C13—C12	119.69 (14)	C4—C3—C2	118.27 (16)
C13—O3—H33	109.5	C4—C3—H5	120.9
N2—C7—C8	122.68 (15)	C2—C3—H5	120.9
N2—C7—H7	118.7	C9—C10—C11	119.95 (16)
C8—C7—H7	118.7	C9—C10—H12	120.0
C13—C8—C9	119.04 (15)	C11—C10—H12	120.0
C13—C8—C7	121.12 (14)	C14—C15—H15A	109.5
C9—C8—C7	119.80 (15)	C14—C15—H15B	109.5
C11—C12—O4	125.26 (15)	H15A—C15—H15B	109.5
C11—C12—C13	119.67 (15)	C14—C15—H15C	109.5
O4—C12—C13	115.07 (14)	H15A—C15—H15C	109.5
C12—C11—C10	120.81 (16)	H15B—C15—H15C	109.5
C12—C11—H11	119.6	O4—C14—C15	107.62 (14)
C10—C11—H11	119.6	O4—C14—H14A	110.2
O2—N1—O1	124.06 (18)	C15—C14—H14A	110.2
O2—N1—C4	118.41 (18)	O4—C14—H14B	110.2
O1—N1—C4	117.52 (18)	C15—C14—H14B	110.2
C5—C6—C1	119.90 (16)	H14A—C14—H14B	108.5
C5—C6—H2	120.0
C7—N2—C1—C2	157.85 (14)	C3—C4—N1—O2	14.4 (2)
C7—N2—C1—C6	−23.4 (2)	C5—C4—N1—O1	15.4 (2)
C1—N2—C7—C8	−179.14 (13)	C3—C4—N1—O1	−165.29 (16)
O3—C13—C8—C9	179.02 (13)	C2—C1—C6—C5	−1.4 (2)
C12—C13—C8—C9	−2.3 (2)	N2—C1—C6—C5	179.93 (14)
O3—C13—C8—C7	−2.9 (2)	C6—C1—C2—C3	1.3 (2)
C12—C13—C8—C7	175.74 (13)	N2—C1—C2—C3	−179.95 (14)
N2—C7—C8—C13	2.8 (2)	C3—C4—C5—C6	0.9 (2)
N2—C7—C8—C9	−179.18 (14)	N1—C4—C5—C6	−179.73 (14)
C14—O4—C12—C11	−9.9 (2)	C1—C6—C5—C4	0.3 (2)
C14—O4—C12—C13	169.91 (14)	C13—C8—C9—C10	0.8 (2)
O3—C13—C12—C11	−178.77 (14)	C7—C8—C9—C10	−177.29 (15)
C8—C13—C12—C11	2.5 (2)	C5—C4—C3—C2	−1.1 (2)
O3—C13—C12—O4	1.4 (2)	N1—C4—C3—C2	179.61 (13)
C8—C13—C12—O4	−177.31 (14)	C1—C2—C3—C4	−0.1 (2)
O4—C12—C11—C10	178.64 (15)	C8—C9—C10—C11	0.5 (2)
C13—C12—C11—C10	−1.2 (2)	C12—C11—C10—C9	−0.4 (3)
C5—C4—N1—O2	−164.98 (16)	C12—O4—C14—C15	−168.97 (14)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H33···N2	0.82	1.88	2.6043 (16)	147