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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 69| Part 3| March 2013| Page o340
doi:10.1107/S1600536813003000

6-Hy­dr­oxy-1,2-di­hydro-4H-pyrrolo­[3,2,1-ij]quinolin-4-one

Victor B. Rybakov,a* Svitlana V. Shishkina,b Igor V. Ukrainets,c Olga V. Gorokhovac and Xeniya V. Andreevac

aDepartment of Chemistry, Moscow State University, Moscow 119992, Russian Federation, bSTC "Institute for Single Crystals", National Academy of Sciences of Ukraine, 60 Lenina ave., Kharkiv 61001, Ukraine, and cNational University of Pharmacy, 4 Blyukhera St., Kharkiv 61002, Ukraine
*Correspondence e-mail: rybakov20021@yandex.ru

(Received 28 January 2013; accepted 29 January 2013; online 2 February 2013)

The mol­ecule of the title compound, C11H9NO2, is essentially planar [r.m.s. deviation of the non-H atoms = 0.056 (1) Å]. In the crystal, strong O—H⋯O hydrogen bonds form zigzag chains along the b axis. The mol­ecules form stacks along the a axis due to π–π inter­actions, the shortest distance between the centroids of the benzene and pyridinone rings being 3.6146 (7) Å.

Related literature

For condensation of secondary anilines with triethyl methane­tricarboxyl­ate, see: Kutyrev & Kappe (1997[Kutyrev, A. & Kappe, T. (1997). J. Heterocycl. Chem. 34, 969-972.]); Jönsson et al. (2004[Jönsson, S., Andersson, G., Fex, T., Fristedt, T., Hedlund, G., Jansson, K., Abramo, L., Fritzson, I., Pekarski, O., Runstrom, A., Sandin, H., Thuvesson, I. & Björk, A. (2004). J. Med. Chem. 47, 2075-2088.]); Ukrainets et al. (2006[Ukrainets, I. V., Sidorenko, L. V., Gorokhova, O. V., Mospanova, E. V. & Shishkin, O. V. (2006). Chem. Heterocycl. Compd, 42, 631-635.], 2010[Ukrainets, I. V., Golik, N. Yu., Andreeva, X. V. & Gorokhova, O. V. (2010). Chem. Heterocycl. Compd, 46, 1459-1466.], 2011[Ukrainets, I. V., Golik, N. Yu., Shemchuk, A. L., Naboka, O. I., Voronina, Yu. V. & Turov, A. V. (2011). Chem. Heterocycl. Compd, 47, 826-832.]). For standard bond lengths, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For a related structure, see: Baumer et al. (2004[Baumer, V. N., Shishkin, O. V., Ukrainets, I. V., Sidorenko, L. V. & Kayal, S. A. E. (2004). Acta Cryst. E60, o2356-o2358.]).

[Scheme 1]

Experimental

Crystal data

  • C11H9NO2

  • Mr = 187.19

  • Monoclinic, P 21 /c

  • a = 7.9987 (3) Å

  • b = 7.6297 (2) Å

  • c = 14.3500 (4) Å

  • β = 101.386 (3)°

  • V = 858.51 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 295 K

  • 0.20 × 0.10 × 0.10 mm
Data collection

  • Agilent Xcalibur Sapphire3 CCD diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Agilent, 2011[Agilent (2011). CrysAlis CCD and CrysAlis RED, Agilent Technologies, Yarnton, England.]) Tmin = 0.983, Tmax = 1.000

  • 7610 measured reflections

  • 2501 independent reflections

  • 1806 reflections with I > 2σ(I)

  • Rint = 0.023
Refinement

  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.125

  • S = 1.07

  • 2501 reflections

  • 131 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O2—H2⋯O1i 1.09 (2) 1.51 (2) 2.5922 (13) 172 (2)
Symmetry code: (i) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CrysAlis CCD (Agilent, 2011[Agilent (2011). CrysAlis CCD and CrysAlis RED, Agilent Technologies, Yarnton, England.]); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Agilent, 2011[Agilent (2011). CrysAlis CCD and CrysAlis RED, Agilent Technologies, Yarnton, England.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536813003000/yk2087sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813003000/yk2087Isup2.hkl

checkCIF report


Comment top

By now the most convenient method of obtaining ethyl esters of N-substituted 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acids which are widely used in synthesis of the biologically active substances is condensation of the corresponding secondary anilines with triethyl methanetricarboxylate (Kutyrev & Kappe, 1997; Jönsson et al., 2004; Ukrainets et al., 2006; 2010; 2011). The method is efficient and gives higher yields. However, as it turned out, in such reactions specific by-products of the same type are also formed besides the targeted esters - (usually 2%–6% by HPLC). Taking condensation of indoline (1) with triethyl methanetricarboxylate (2) as an example (Fig. 1), we showed that in this case the by-product is 6-hydroxy-1,2-dihydro-4H-pyrrolo[3,2,1-i,j]quinolin-4-one (3), and its yield is determined by water content in the initial reaction mixture. The source of this impurity can be our main product - ethyl 6-hydroxy-4-oxo-1,2-dihydro-4H-pyrrolo[3,2,1-i,j]- quinoline-5-carboxylate (4), which readily undergoes partial hydrolysis and then decarboxylation at high temperature.

In the title molecule, C11H9NO2, the heterotricycle is essentially planar (Fig. 2). The bond lengths and angles are within the normal ranges (Allen et al., 1987). Strong O2—H2···O1i intermolecular hydrogen bonds (Table 1) form folded chains along the b axis (Fig. 3). Symmetry code: (i) -x, y + 1/2, -z + 1/2.

Related literature top

For condensation of secondary anilines with triethyl methanetricarboxylate, see: Kutyrev & Kappe (1997); Jönsson et al. (2004); Ukrainets et al. (2006, 2010, 2011). For standard bond lengths, see: Allen et al. (1987). For related structure, see: Baumer et al. (2004).

Experimental top

As shown in Fig. 1, Indoline (1) (11.2 ml, 0.1 mol) was added dropwise with stirring to triethyl methanetricarboxylate (2) (63.3 ml, 0.3 mol) heated to 488 K, at such a rate that the temperature of the reaction mixture was maintained within ±5 K of the initial temperature. The ethanol eliminated during the reaction was distilled through a suitable still–head. After adding all the indoline, the reaction mixture was kept at the same temperature for 30 min, after which it was cooled. The excess of triethyl methanetricarboxylate was removed in vacuo. To the residue was added 50 ml of xylene. The insoluble solid quinolin-4-one (3) was filtered off, washed with hexane, and dried. Yield: 0.77 g (4.1%). M.p. 577–579 K (DMF).

Refinement top

The H atom of hydroxyl group was located from electron density difference map and refined isotropically. The methylene and aromatic H atoms were placed in calculated positions and refined in the riding model approximation with C—H = 0.97 Å for methylene and C—H = 0.93 Å for aryl H atoms with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: CrysAlis CCD (Agilent, 2011); cell refinement: CrysAlis CCD (Agilent, 2011); data reduction: CrysAlis RED (Agilent, 2011); 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, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. Synthesis path to the title compound.
[Figure 2] Fig. 2. View of the title compound with the atom numbering scheme. The displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as a small spheres of arbitrary radius.
[Figure 3] Fig. 3. The O—H···O hydrogen bonds in the crystals of the title compound (shown by dashed lines). Symmetry code: (i) -x, y+1/2, -z+1/2.
6-Hydroxy-1,2-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-4-one top
Crystal data top
C11H9NO2F(000) = 392
Mr = 187.19Dx = 1.448 Mg m−3
Monoclinic, P21/cMelting point = 577–579 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 7.9987 (3) ÅCell parameters from 2056 reflections
b = 7.6297 (2) Åθ = 3.0–30.0°
c = 14.3500 (4) ŵ = 0.10 mm−1
β = 101.386 (3)°T = 295 K
V = 858.51 (5) Å3Prism, colourless
Z = 40.20 × 0.10 × 0.10 mm
Data collection top
Agilent Xcalibur Sapphire3 CCD
diffractometer		2501 independent reflections
Radiation source: Enhance (Mo) X–ray Source1806 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 16.1827 pixels mm-1θmax = 30.0°, θmin = 3.0°
ω scansh = −10→11
Absorption correction: multi-scan
(CrysAlis RED; Agilent, 2011)		k = −10→10
Tmin = 0.983, Tmax = 1.000l = −20→19
7610 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0595P)2 + 0.0832P]
where P = (Fo2 + 2Fc2)/3
2501 reflections(Δ/σ)max < 0.001
131 parametersΔρmax = 0.23 e Å−3
0 restraintsΔρmin = −0.15 e Å−3
Crystal data top
C11H9NO2V = 858.51 (5) Å3
Mr = 187.19Z = 4
Monoclinic, P21/cMo Kα radiation
a = 7.9987 (3) ŵ = 0.10 mm−1
b = 7.6297 (2) ÅT = 295 K
c = 14.3500 (4) Å0.20 × 0.10 × 0.10 mm
β = 101.386 (3)°
Data collection top
Agilent Xcalibur Sapphire3 CCD
diffractometer		2501 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Agilent, 2011)		1806 reflections with I > 2σ(I)
Tmin = 0.983, Tmax = 1.000Rint = 0.023
7610 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.23 e Å−3
2501 reflectionsΔρmin = −0.15 e Å−3
131 parameters
Special details top

Experimental. CrysAlis RED (Agilent Technologies, 2011). Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R–factor wRand 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 > 2σ(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 (Å2) top
xyzUiso*/Ueq
O10.20058 (12)0.29009 (13)0.28449 (6)0.0523 (3)
O2−0.01907 (13)0.82083 (12)0.38558 (7)0.0489 (3)
H2−0.093 (3)0.819 (3)0.3132 (16)0.101 (7)*
N10.26368 (13)0.36896 (13)0.43936 (7)0.0369 (2)
C10.25940 (14)0.48889 (16)0.51022 (8)0.0345 (3)
C20.35421 (15)0.43260 (18)0.59709 (8)0.0407 (3)
C30.36190 (17)0.5414 (2)0.67396 (9)0.0507 (4)
H30.42360.50860.73330.061*
C40.27589 (18)0.7023 (2)0.66225 (10)0.0519 (4)
H40.28360.77630.71440.062*
C50.18033 (17)0.75496 (18)0.57616 (9)0.0439 (3)
H50.12300.86170.57090.053*
C60.17035 (15)0.64553 (16)0.49625 (8)0.0354 (3)
C70.07582 (15)0.67526 (15)0.40090 (8)0.0362 (3)
C80.08626 (15)0.55614 (16)0.33158 (8)0.0391 (3)
H80.02620.57850.27040.047*
C90.18435 (15)0.39879 (16)0.34778 (8)0.0379 (3)
C100.36451 (18)0.21387 (18)0.47642 (10)0.0479 (3)
H10B0.46090.19910.44540.057*
H10A0.29510.10870.46700.057*
C110.42503 (18)0.25294 (19)0.58354 (10)0.0487 (3)
H11B0.38080.16650.62190.058*
H11A0.54860.25300.60070.058*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0555 (6)0.0572 (6)0.0394 (5)0.0028 (5)−0.0024 (4)−0.0165 (4)
O20.0565 (6)0.0446 (5)0.0426 (5)0.0102 (4)0.0021 (4)0.0046 (4)
N10.0369 (5)0.0396 (5)0.0321 (5)0.0004 (4)0.0017 (4)−0.0005 (4)
C10.0318 (5)0.0421 (6)0.0288 (5)−0.0053 (5)0.0044 (4)0.0008 (4)
C20.0345 (6)0.0538 (7)0.0320 (6)−0.0018 (5)0.0020 (5)0.0062 (5)
C30.0463 (7)0.0741 (10)0.0284 (6)−0.0025 (7)−0.0008 (5)0.0013 (6)
C40.0527 (8)0.0683 (9)0.0339 (7)−0.0054 (7)0.0063 (6)−0.0129 (6)
C50.0445 (7)0.0480 (7)0.0394 (7)−0.0032 (6)0.0087 (5)−0.0069 (5)
C60.0343 (6)0.0409 (6)0.0304 (5)−0.0046 (5)0.0050 (4)−0.0002 (5)
C70.0351 (6)0.0394 (6)0.0332 (6)−0.0019 (5)0.0043 (4)0.0043 (5)
C80.0388 (6)0.0462 (7)0.0292 (6)−0.0026 (5)−0.0007 (5)0.0020 (5)
C90.0350 (6)0.0451 (6)0.0315 (6)−0.0054 (5)0.0015 (5)−0.0041 (5)
C100.0469 (7)0.0455 (7)0.0485 (8)0.0067 (6)0.0029 (6)0.0036 (6)
C110.0417 (7)0.0592 (8)0.0429 (7)0.0056 (6)0.0025 (6)0.0124 (6)
Geometric parameters (Å, º) top
O1—C91.2555 (14)C4—H40.9300
O2—C71.3387 (15)C5—C61.4079 (18)
O2—H21.09 (2)C5—H50.9300
N1—C91.3610 (15)C6—C71.4445 (16)
N1—C11.3733 (15)C7—C81.3622 (17)
N1—C101.4711 (16)C8—C91.4279 (17)
C1—C61.3855 (17)C8—H80.9300
C1—C21.3930 (16)C10—C111.547 (2)
C2—C31.3721 (19)C10—H10B0.9700
C2—C111.5104 (19)C10—H10A0.9700
C3—C41.401 (2)C11—H11B0.9700
C3—H30.9300C11—H11A0.9700
C4—C51.3780 (19)
C7—O2—H2109.2 (11)O2—C7—C8123.24 (11)
C9—N1—C1121.90 (10)O2—C7—C6117.37 (11)
C9—N1—C10126.97 (11)C8—C7—C6119.40 (11)
C1—N1—C10111.12 (10)C7—C8—C9123.57 (10)
N1—C1—C6123.70 (10)C7—C8—H8118.2
N1—C1—C2111.62 (11)C9—C8—H8118.2
C6—C1—C2124.68 (11)O1—C9—N1119.54 (11)
C3—C2—C1117.58 (13)O1—C9—C8124.72 (11)
C3—C2—C11133.96 (12)N1—C9—C8115.74 (11)
C1—C2—C11108.44 (11)N1—C10—C11104.24 (10)
C2—C3—C4119.38 (12)N1—C10—H10B110.9
C2—C3—H3120.3C11—C10—H10B110.9
C4—C3—H3120.3N1—C10—H10A110.9
C5—C4—C3122.35 (13)C11—C10—H10A110.9
C5—C4—H4118.8H10B—C10—H10A108.9
C3—C4—H4118.8C2—C11—C10104.54 (10)
C4—C5—C6119.32 (13)C2—C11—H11B110.8
C4—C5—H5120.3C10—C11—H11B110.8
C6—C5—H5120.3C2—C11—H11A110.8
C1—C6—C5116.67 (11)C10—C11—H11A110.8
C1—C6—C7115.50 (10)H11B—C11—H11A108.9
C5—C6—C7127.82 (12)
C9—N1—C1—C62.51 (18)C1—C6—C7—O2176.62 (10)
C10—N1—C1—C6−178.40 (11)C5—C6—C7—O2−2.35 (19)
C9—N1—C1—C2−177.90 (11)C1—C6—C7—C8−3.23 (17)
C10—N1—C1—C21.20 (15)C5—C6—C7—C8177.81 (12)
N1—C1—C2—C3179.39 (11)O2—C7—C8—C9−178.65 (11)
C6—C1—C2—C3−1.01 (19)C6—C7—C8—C91.18 (19)
N1—C1—C2—C11−1.98 (14)C1—N1—C9—O1175.65 (11)
C6—C1—C2—C11177.61 (11)C10—N1—C9—O1−3.3 (2)
C1—C2—C3—C4−0.2 (2)C1—N1—C9—C8−4.50 (17)
C11—C2—C3—C4−178.33 (14)C10—N1—C9—C8176.56 (11)
C2—C3—C4—C51.2 (2)C7—C8—C9—O1−177.46 (12)
C3—C4—C5—C6−1.2 (2)C7—C8—C9—N12.70 (18)
N1—C1—C6—C5−179.39 (11)C9—N1—C10—C11179.12 (11)
C2—C1—C6—C51.07 (18)C1—N1—C10—C110.08 (15)
N1—C1—C6—C71.52 (17)C3—C2—C11—C10−179.78 (15)
C2—C1—C6—C7−178.02 (11)C1—C2—C11—C101.92 (14)
C4—C5—C6—C10.04 (18)N1—C10—C11—C2−1.19 (14)
C4—C5—C6—C7179.00 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O1i1.09 (2)1.51 (2)2.5922 (13)172.0 (19)
Symmetry code: (i) −x, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC11H9NO2
Mr187.19
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)7.9987 (3), 7.6297 (2), 14.3500 (4)
β (°) 101.386 (3)
V (Å3)858.51 (5)
Z4
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.20 × 0.10 × 0.10
Data collection
DiffractometerAgilent Xcalibur Sapphire3 CCD
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Agilent, 2011)
Tmin, Tmax0.983, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections		7610, 2501, 1806
Rint0.023
(sin θ/λ)max (Å−1)0.703
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.125, 1.07
No. of reflections2501
No. of parameters131
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.23, −0.15

Computer programs: CrysAlis CCD (Agilent, 2011), CrysAlis RED (Agilent, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O1i1.09 (2)1.51 (2)2.5922 (13)172.0 (19)
Symmetry code: (i) −x, y+1/2, −z+1/2.
 

References

First citationAgilent (2011). CrysAlis CCD and CrysAlis RED, Agilent Technologies, Yarnton, England.  Google Scholar
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 First citationBaumer, V. N., Shishkin, O. V., Ukrainets, I. V., Sidorenko, L. V. & Kayal, S. A. E. (2004). Acta Cryst. E60, o2356–o2358.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 69| Part 3| March 2013| Page o340
doi:10.1107/S1600536813003000
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