1-Ethyl-4-hydroxy­quinolin-2(1H)-one

X-ray diffraction study of the title compound, C₁₁H₁₁NO₂, (I), has shown that the molecular geometry is similar to that of 1-ethyl-4-hydroxy-2-oxo-1,2-di­hydro­quinoline-3-carboxyl­ic acid, (II) [Shishkina, Shishkin, Ukrainets, Dakkah & Sidorenko (2002). Acta Cryst. E58, o254-o256]. Observed elongations of the bonds around the N atom are caused by steric hindrance between the ethyl H atoms and the planar quinolone fragment. Exocyclic angles in the 4-position are also distorted, but, in contrast to (II), this distortion is caused by the formation of zigzag hydrogen-bonded chains along the [010] direction.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.036
• wR factor = 0.103
• Data-to-parameter ratio = 8.9

checkCIF/PLATON results

No syntax errors found



Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           26.45
           From the CIF: _reflns_number_total               1131
           Count of symmetry unique reflns         1139
           Completeness (_total/calc)             99.30%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present           no

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: P3 (Siemens,1989); cell refinement: P3; data reduction: XDISK and XPREP (Siemens, 1991); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Siemens, 1991); software used to prepare material for publication: WinGX (Farrugia, 1999).

(I)

Crystal data

C11H11NO2	F(000) = 400
Mr = 189.21	Dx = 1.348 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 24 reflections
a = 7.8474 (12) Å	θ = 11.0–12.0°
b = 8.4660 (14) Å	µ = 0.09 mm^−1
c = 14.033 (3) Å	T = 293 K
V = 932.3 (3) Å^3	Polyhedron, colourless
Z = 4	0.35 × 0.3 × 0.3 mm

Data collection

Siemens P3/PC diffractometer	θmax = 26.5°, θmin = 2.8°
2θ/θ scans	h = 0→9
1226 measured reflections	k = 0→10
1131 independent reflections	l = 0→17
974 reflections with I > 2σ(I)	2 standard reflections every 98 reflections
Rint = 0.016	intensity decay: 1%

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.036	w = 1/[σ^2(Fo^2) + (0.0774P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.103	(Δ/σ)max < 0.001
S = 0.97	Δρmax = 0.13 e Å^−3
1131 reflections	Δρmin = −0.13 e Å^−3
127 parameters

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.53866 (18)	1.11314 (17)	0.13981 (9)	0.0505 (4)
O2	0.74016 (19)	0.62483 (17)	0.26303 (10)	0.0541 (4)
H2	0.6473	0.6219	0.2898	0.065*
N1	0.79890 (18)	1.02257 (18)	0.09523 (10)	0.0369 (4)
C2	0.6498 (2)	1.0060 (2)	0.14664 (13)	0.0388 (4)
C3	0.6284 (2)	0.8687 (2)	0.20415 (13)	0.0401 (4)
H3	0.5275	0.8556	0.2379	0.048*
C4	0.7513 (2)	0.7569 (2)	0.21091 (12)	0.0376 (4)
C4A	0.9112 (2)	0.7775 (2)	0.16043 (12)	0.0339 (4)
C5	1.0444 (3)	0.6677 (2)	0.16819 (13)	0.0416 (4)
H5	1.0304	0.5783	0.2059	0.05*
C6	1.1953 (3)	0.6910 (3)	0.12064 (14)	0.0469 (5)
H6	1.2831	0.6179	0.1263	0.056*
C7	1.2161 (3)	0.8242 (3)	0.06404 (14)	0.0467 (5)
H7	1.3183	0.8397	0.0318	0.056*
C8	1.0876 (2)	0.9334 (2)	0.05499 (14)	0.0421 (5)
H8	1.1038	1.0219	0.0168	0.051*
C8A	0.9317 (2)	0.9127 (2)	0.10297 (12)	0.0341 (4)
C9	0.8166 (3)	1.1655 (2)	0.03641 (14)	0.0423 (5)
H9A	0.7058	1.1946	0.0113	0.051*
H9B	0.8907	1.1426	−0.0172	0.051*
C10	0.8888 (3)	1.3028 (2)	0.09170 (16)	0.0495 (5)
H10A	0.8996	1.3927	0.0504	0.074*
H10B	0.9989	1.2749	0.1163	0.074*
H10C	0.8139	1.3283	0.1436	0.074*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0455 (7)	0.0487 (8)	0.0572 (8)	0.0119 (7)	0.0070 (7)	0.0034 (7)
O2	0.0469 (8)	0.0493 (8)	0.0661 (8)	0.0001 (7)	0.0127 (7)	0.0212 (8)
N1	0.0367 (7)	0.0356 (8)	0.0383 (7)	0.0008 (7)	0.0023 (6)	0.0010 (7)
C2	0.0367 (9)	0.0375 (9)	0.0422 (9)	−0.0006 (8)	0.0007 (7)	−0.0051 (9)
C3	0.0331 (8)	0.0449 (10)	0.0423 (9)	−0.0035 (9)	0.0067 (8)	0.0003 (8)
C4	0.0405 (9)	0.0354 (9)	0.0368 (8)	−0.0052 (9)	−0.0003 (7)	0.0000 (8)
C4A	0.0362 (9)	0.0316 (8)	0.0338 (8)	−0.0043 (7)	−0.0008 (7)	−0.0042 (7)
C5	0.0477 (10)	0.0363 (9)	0.0408 (8)	0.0026 (9)	−0.0014 (9)	−0.0016 (8)
C6	0.0414 (10)	0.0456 (10)	0.0538 (11)	0.0097 (10)	0.0030 (9)	−0.0086 (9)
C7	0.0417 (10)	0.0486 (11)	0.0498 (10)	−0.0008 (9)	0.0127 (9)	−0.0089 (10)
C8	0.0453 (10)	0.0368 (10)	0.0444 (9)	−0.0054 (9)	0.0097 (8)	−0.0053 (8)
C8A	0.0378 (9)	0.0336 (9)	0.0309 (8)	−0.0032 (8)	0.0002 (7)	−0.0074 (7)
C9	0.0441 (10)	0.0405 (10)	0.0425 (9)	0.0026 (9)	0.0027 (9)	0.0074 (8)
C10	0.0546 (11)	0.0391 (10)	0.0548 (11)	−0.0016 (10)	0.0017 (11)	0.0026 (10)

Geometric parameters (Å, º)

O1—C2	1.262 (2)	C5—H5	0.93
O2—C4	1.339 (2)	C6—C7	1.389 (3)
O2—H2	0.82	C6—H6	0.93
N1—C2	1.382 (2)	C7—C8	1.374 (3)
N1—C8A	1.402 (2)	C7—H7	0.93
N1—C9	1.471 (2)	C8—C8A	1.407 (3)
C2—C3	1.425 (3)	C8—H8	0.93
C3—C4	1.355 (3)	C9—C10	1.509 (3)
C3—H3	0.93	C9—H9A	0.97
C4—C4A	1.452 (2)	C9—H9B	0.97
C4A—C5	1.403 (3)	C10—H10A	0.96
C4A—C8A	1.409 (2)	C10—H10B	0.96
C5—C6	1.373 (3)	C10—H10C	0.96
C4—O2—H2	109.5	C8—C7—C6	120.87 (18)
C2—N1—C8A	121.46 (15)	C8—C7—H7	119.6
C2—N1—C9	117.17 (15)	C6—C7—H7	119.6
C8A—N1—C9	121.27 (14)	C7—C8—C8A	120.64 (18)
O1—C2—N1	118.20 (16)	C7—C8—H8	119.7
O1—C2—C3	123.22 (17)	C8A—C8—H8	119.7
N1—C2—C3	118.58 (16)	N1—C8A—C8	121.77 (16)
C4—C3—C2	121.75 (17)	N1—C8A—C4A	119.90 (15)
C4—C3—H3	119.1	C8—C8A—C4A	118.33 (17)
C2—C3—H3	119.1	N1—C9—C10	112.39 (15)
O2—C4—C3	125.16 (17)	N1—C9—H9A	109.1
O2—C4—C4A	115.04 (16)	C10—C9—H9A	109.1
C3—C4—C4A	119.80 (16)	N1—C9—H9B	109.1
C5—C4A—C8A	119.80 (16)	C10—C9—H9B	109.1
C5—C4A—C4	121.80 (16)	H9A—C9—H9B	107.9
C8A—C4A—C4	118.40 (16)	C9—C10—H10A	109.5
C6—C5—C4A	120.64 (18)	C9—C10—H10B	109.5
C6—C5—H5	119.7	H10A—C10—H10B	109.5
C4A—C5—H5	119.7	C9—C10—H10C	109.5
C5—C6—C7	119.72 (19)	H10A—C10—H10C	109.5
C5—C6—H6	120.1	H10B—C10—H10C	109.5
C7—C6—H6	120.1
C8A—N1—C2—O1	176.66 (16)	C5—C6—C7—C8	0.1 (3)
C9—N1—C2—O1	0.3 (2)	C6—C7—C8—C8A	0.0 (3)
C8A—N1—C2—C3	−3.8 (2)	C2—N1—C8A—C8	−176.36 (16)
C9—N1—C2—C3	179.85 (16)	C9—N1—C8A—C8	−0.1 (2)
O1—C2—C3—C4	−179.11 (18)	C2—N1—C8A—C4A	3.3 (2)
N1—C2—C3—C4	1.3 (3)	C9—N1—C8A—C4A	179.57 (15)
C2—C3—C4—O2	−179.71 (17)	C7—C8—C8A—N1	179.76 (16)
C2—C3—C4—C4A	1.5 (3)	C7—C8—C8A—C4A	0.1 (3)
O2—C4—C4A—C5	−1.4 (2)	C5—C4A—C8A—N1	−179.91 (16)
C3—C4—C4A—C5	177.55 (17)	C4—C4A—C8A—N1	−0.4 (2)
O2—C4—C4A—C8A	179.17 (15)	C5—C4A—C8A—C8	−0.2 (2)
C3—C4—C4A—C8A	−1.9 (2)	C4—C4A—C8A—C8	179.25 (16)
C8A—C4A—C5—C6	0.3 (3)	C2—N1—C9—C10	86.8 (2)
C4—C4A—C5—C6	−179.17 (17)	C8A—N1—C9—C10	−89.6 (2)
C4A—C5—C6—C7	−0.2 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O1^i	0.82	1.76	2.580 (2)	173

Symmetry code: (i) −x+1, y−1/2, −z+1/2.