Ethyl 5-chloro-9-eth­oxy-2-oxo-2H-pyrano[2,3-g]quinoline-8-carboxyl­ate

Oliveira, C.D.; Romeiro, G.A.; Skakle, J.M.S.; Wardell, J.L.; Wardell, S.M.S.V.

doi:10.1107/S160053680600715X

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 62| Part 4| April 2006| Pages o1494-o1495

https://doi.org/10.1107/S160053680600715X

Ethyl 5-chloro-9-ethoxy-2-oxo-2H-pyrano[2,3-g]quinoline-8-carboxylate

César D. de Oliveira,^a Gilberto A. Romeiro,^a Janet M. S. Skakle,^b ^* James L. Wardell ^c and Solange M. S. V. Wardell ^d

^aInstituto de Química, Departamento de Química Inorgânica, Universidade Federal Fluminense, Outeiro de São João Batista s/n, Campus do Valonguinho–Centro, Niterói, RJ 24020-150, Brazil, ^bDepartment of Chemistry, College of Physical Sciences, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland, ^cDepartamento de Química Inorgânica, Instituto de Química, Universidade Federal do Rio de Janeiro, 21945-970 Rio de Janeiro, RJ, Brazil, and ^dLaboratory of Organic Synthesis of Far-Manguinhos/FIOCRUZ, R. Sizenando Nabuco, 100 Manguinhos, 21041-250 Rio de Janeiro, RJ, Brazil
^*Correspondence e-mail: j.skakle@abdn.ac.uk

(Received 15 February 2006; accepted 27 February 2006; online 22 March 2006)

The title compound, C₁₇H₁₄ClNO₅ has been shown to be isostructural with the bromo analogue, confirming the site of alkylation within the structure and the pyranoquinoline ring system. As with the bromo analogue, the molecules are linked by a C—H⋯O hydrogen bond forming C(5) chains along [001].

Comment

Following from the successful bromination of a pyranoquinoline derivative (da Matta et al., 2000 ; de Oliveira, 2003 ) at the carbonyl site of compound (1) (see scheme) (de Oliveira, 2006 ), chlorination was also attempted. As with the bromo compound (de Oliveira et al., 2006), alkylation occurs at the carbonyl site (Fig. 1).

The structure also reveals the same hydrogen bonding scheme with intramolecular hydrogen bonds (Table 1) supporting the structure, and C(5) chains (Bernstein et al., 1995 ) forming along [001] (de Oliveira et al., 2006).

Figure 1
The molecular structure of the title compound, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.

Experimental

The title compound was obtained from the reaction between EtBr and (1) in DMF solution in the presence of K₂CO₃ (de Oliveira, 2003). Pure product (2) was obtained from the reaction mixture by column chromatography using hexane–ethyl acetate as the eluent (gradient 1:4 to 1:1). Crystals suitable for X-ray crystallography were grown from ethyl acetate (65% yield; m.p. 433–434 K).

Crystal data

C₁₇H₁₄ClNO₅
M_r = 347.74
Orthorhombic, P n a 2₁
a = 7.1480 (9) Å
b = 19.653 (3) Å
c = 11.1150 (14) Å
V = 1561.4 (3) Å³
Z = 4
D_x = 1.479 Mg m⁻³
Mo Kα radiation
Cell parameters from 1346 reflections
θ = 3.5–19.3°
μ = 0.27 mm⁻¹
T = 291 (2) K
Needle, colourless
0.38 × 0.10 × 0.02 mm

Data collection

Bruker SMART 1000 CCD area-detector diffractometer
ω scans
Absorption correction: multi-scan (SADABS; Bruker, 2000 )T_min = 0.866, T_max = 0.995
15310 measured reflections
5017 independent reflections
1745 reflections with I > 2σ(I)
R_int = 0.100
θ_max = 32.5°
h = −10 → 10
k = −29 → 29
l = −16 → 13

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.076
S = 0.79
5017 reflections
219 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0131P)²] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max < 0.001
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.17 e Å⁻³
Absolute structure: Flack (1983 ), 2061 Friedel pairs
Flack parameter: 0.00 (7)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H9⋯O11ⁱ	0.93	2.55	3.357 (4)	145
C4—H4⋯O31	0.93	2.40	2.730 (4)	101
C9—H9⋯Cl7	0.93	2.71	3.071 (3)	104
C21—H21A⋯O32	0.97	2.30	2.927 (4)	122
Symmetry code: (i) $[-x+1, -y, z-{\script{1\over 2}}]$ .

All H atoms were located in difference maps and then treated as riding atoms, with C—H distances of 0.95 (aromatic) or 0.96 Å (methyl) and U_iso(H) values of 1.2U_eq(C) (aromatic) or 1.5U_eq(C) (methyl). PLATON (Spek, 2003 ) was used for the hydrogen-bonding analysis.

Data collection: SMART (Bruker, 1998 ); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: OSCAIL (McArdle, 2003 ) and SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: CIFTAB (Sheldrick, 1997).

Supporting information

Crystal structure: contains datablocks global, 2. DOI: https://doi.org/10.1107/S160053680600715X/wk2004sup1.cif

Structure factors: contains datablock 2. DOI: https://doi.org/10.1107/S160053680600715X/wk20042sup2.hkl

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: CIFTAB (Sheldrick, 1997).

Ethyl 5-chloro-9-ethoxy-2-oxo-2H-pyrano[2,3-g]quinoline-8-carboxylate top

Crystal data top

C₁₇H₁₄ClNO₅	F(000) = 720
M_r = 347.74	D_x = 1.479 Mg m⁻³
Orthorhombic, Pna2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 1346 reflections
a = 7.1480 (9) Å	θ = 3.5–19.3°
b = 19.653 (3) Å	µ = 0.27 mm⁻¹
c = 11.1150 (14) Å	T = 291 K
V = 1561.4 (3) Å³	Needle, clear
Z = 4	0.38 × 0.10 × 0.02 mm

Data collection top

Bruker SMART 1000 CCD area-detector diffractometer	5017 independent reflections
Radiation source: fine-focus sealed tube	1745 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.100
ω scans	θ_max = 32.5°, θ_min = 2.1°
Absorption correction: multi-scan	h = −10→10
T_min = 0.866, T_max = 0.995	k = −29→29
15310 measured reflections	l = −16→13

Refinement top

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)] = 0.052	H-atom parameters constrained
wR(F²) = 0.076	w = 1/[σ²(F_o²) + (0.0131P)²] where P = (F_o² + 2F_c²)/3
S = 0.79	(Δ/σ)_max < 0.001
5017 reflections	Δρ_max = 0.27 e Å⁻³
219 parameters	Δρ_min = −0.17 e Å⁻³
1 restraint	Absolute structure: Flack (1983)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.00 (7)

Special details top

Experimental. IR (KBr, cm^-1): 2979, 1749, 1718, 1618, 1590, 1342, 1302. ¹H NMR (DMSO-d₆, 300 MHz): δ 1.51 (t, J = 7.2 Hz, 3H), 1.59 (t, J = 6.9 Hz, 3H), 4.46 (q, J = 6.9 Hz, 2H), 4.56 (q, J = 7.2 Hz, 2H), 6.93 (d, J = 9.9 Hz, 1H), 8.18 (s, 1H), 8.57 (d, J = 9.9 Hz, 1H), 9.25 (s, 1H). ¹³C NMR (DMSO-d₆, 75 MHz): δ 13.9, 15.3, 61.7, 72.3, 107.2, 115.1, 120.3, 121.0, 125.3, 131.5, 139.4, 142.5, 150.3, 151.9, 158.5, 162.2, 164.3.

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 (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.5477 (4)	0.26739 (15)	0.7928 (2)	0.0384 (8)
C2	0.5707 (5)	0.32697 (15)	0.8673 (2)	0.0396 (9)
O2	0.6140 (3)	0.31280 (9)	0.98103 (16)	0.0554 (6)
C21	0.7298 (5)	0.35674 (14)	1.0542 (3)	0.0515 (9)
H21A	0.6546	0.3921	1.0911	0.062*
H21B	0.8259	0.3780	1.0054	0.062*
C22	0.8169 (5)	0.31246 (17)	1.1489 (3)	0.0742 (11)
H22A	0.7203	0.2894	1.1929	0.111*
H22B	0.8887	0.3401	1.2031	0.111*
H22C	0.8972	0.2796	1.1114	0.111*
C3	0.5482 (4)	0.38991 (15)	0.8139 (3)	0.0394 (8)
C31	0.5414 (5)	0.45618 (17)	0.8800 (3)	0.0492 (9)
O31	0.6132 (4)	0.50542 (10)	0.81272 (17)	0.0627 (7)
O32	0.4740 (3)	0.46481 (10)	0.9783 (2)	0.0691 (7)
C32	0.5921 (6)	0.57510 (16)	0.8570 (3)	0.0734 (12)
H32A	0.6493	0.5799	0.9357	0.088*
H32B	0.4608	0.5871	0.8632	0.088*
C33	0.6887 (5)	0.61997 (15)	0.7671 (3)	0.0808 (13)
H33A	0.8192	0.6086	0.7642	0.121*
H33B	0.6745	0.6667	0.7906	0.121*
H33C	0.6340	0.6133	0.6891	0.121*
C4	0.5045 (4)	0.39197 (14)	0.6895 (3)	0.0448 (9)
H4	0.4947	0.4348	0.6544	0.054*
N5	0.4765 (4)	0.33948 (13)	0.6193 (2)	0.0460 (7)
C6	0.4954 (4)	0.27698 (14)	0.6713 (2)	0.0383 (7)
C7	0.4651 (4)	0.21757 (16)	0.6005 (2)	0.0430 (8)
Cl7	0.39837 (12)	0.22796 (4)	0.45262 (8)	0.0614 (2)
C8	0.4881 (4)	0.15307 (15)	0.6457 (3)	0.0403 (8)
C9	0.4591 (4)	0.09056 (16)	0.5782 (3)	0.0516 (9)
H9	0.4179	0.0926	0.4989	0.062*
C10	0.4911 (5)	0.03104 (17)	0.6289 (3)	0.0591 (10)
H10	0.4684	−0.0082	0.5843	0.071*
C11	0.5598 (5)	0.02387 (17)	0.7506 (3)	0.0586 (10)
O11	0.6028 (4)	−0.02798 (11)	0.8000 (2)	0.0799 (9)
O12	0.5750 (3)	0.08350 (10)	0.81648 (17)	0.0533 (6)
C13	0.5440 (4)	0.14710 (14)	0.7658 (3)	0.0417 (8)
C14	0.5745 (4)	0.20186 (14)	0.8390 (2)	0.0417 (8)
H14	0.6123	0.1957	0.9183	0.050*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.040 (2)	0.0420 (19)	0.0329 (17)	−0.0042 (16)	0.0025 (14)	0.0021 (15)
C2	0.037 (2)	0.049 (2)	0.0322 (18)	−0.0073 (16)	−0.0010 (14)	0.0006 (15)
O2	0.0779 (18)	0.0508 (13)	0.0374 (14)	−0.0159 (12)	−0.0108 (12)	0.0064 (10)
C21	0.060 (3)	0.055 (2)	0.039 (2)	−0.0083 (18)	−0.0076 (16)	−0.0096 (15)
C22	0.094 (3)	0.075 (2)	0.054 (2)	0.000 (2)	−0.022 (2)	0.0072 (18)
C3	0.042 (2)	0.045 (2)	0.0313 (18)	−0.0024 (15)	0.0027 (15)	−0.0029 (14)
C31	0.060 (3)	0.043 (2)	0.045 (2)	0.0036 (19)	−0.0045 (18)	0.0000 (17)
O31	0.094 (2)	0.0416 (14)	0.0527 (14)	−0.0067 (14)	0.0116 (12)	−0.0089 (11)
O32	0.102 (2)	0.0574 (14)	0.0482 (17)	0.0106 (14)	0.0127 (15)	−0.0039 (11)
C32	0.104 (3)	0.040 (2)	0.076 (3)	0.001 (2)	0.005 (2)	−0.0202 (18)
C33	0.108 (4)	0.043 (2)	0.091 (3)	−0.003 (2)	−0.002 (3)	−0.002 (2)
C4	0.051 (2)	0.0366 (18)	0.047 (2)	0.0034 (17)	−0.0014 (16)	0.0078 (16)
N5	0.056 (2)	0.0437 (16)	0.0382 (16)	0.0017 (13)	−0.0065 (13)	0.0011 (13)
C6	0.047 (2)	0.0358 (18)	0.0323 (16)	−0.0019 (16)	−0.0014 (14)	−0.0012 (15)
C7	0.038 (2)	0.063 (2)	0.0277 (16)	−0.0005 (17)	−0.0046 (14)	−0.0009 (15)
Cl7	0.0839 (7)	0.0643 (5)	0.0361 (4)	0.0005 (5)	−0.0135 (5)	−0.0033 (4)
C8	0.041 (2)	0.0401 (19)	0.0400 (19)	−0.0002 (16)	0.0013 (15)	−0.0015 (15)
C9	0.063 (3)	0.052 (2)	0.0397 (19)	−0.0050 (19)	0.0057 (17)	−0.0111 (16)
C10	0.083 (3)	0.042 (2)	0.053 (2)	−0.003 (2)	−0.001 (2)	−0.0132 (17)
C11	0.070 (3)	0.043 (2)	0.062 (3)	−0.003 (2)	0.004 (2)	−0.0017 (19)
O11	0.110 (3)	0.0407 (16)	0.0885 (18)	0.0019 (16)	−0.0146 (16)	0.0038 (14)
O12	0.0716 (18)	0.0401 (13)	0.0482 (13)	−0.0033 (13)	−0.0040 (12)	0.0032 (10)
C13	0.044 (2)	0.041 (2)	0.0396 (19)	−0.0001 (16)	0.0024 (16)	0.0050 (15)
C14	0.045 (2)	0.0415 (19)	0.0383 (17)	−0.0061 (16)	−0.0019 (15)	0.0011 (15)

Geometric parameters (Å, º) top

C1—C14	1.400 (3)	C33—H33A	0.9600
C1—C6	1.414 (4)	C33—H33B	0.9600
C1—C2	1.444 (4)	C33—H33C	0.9600
C2—O2	1.331 (3)	C4—N5	1.309 (3)
C2—C3	1.381 (4)	C4—H4	0.9300
O2—C21	1.446 (3)	N5—C6	1.364 (3)
C21—C22	1.501 (4)	C6—C7	1.425 (3)
C21—H21A	0.9700	C7—C8	1.373 (4)
C21—H21B	0.9700	C7—Cl7	1.724 (3)
C22—H22A	0.9600	C8—C13	1.399 (4)
C22—H22B	0.9600	C8—C9	1.454 (4)
C22—H22C	0.9600	C9—C10	1.318 (4)
C3—C4	1.418 (4)	C9—H9	0.9300
C3—C31	1.497 (4)	C10—C11	1.446 (4)
C31—O32	1.206 (3)	C10—H10	0.9300
C31—O31	1.326 (3)	C11—O11	1.198 (3)
O31—C32	1.463 (3)	C11—O12	1.386 (3)
C32—C33	1.500 (4)	O12—C13	1.389 (3)
C32—H32A	0.9700	C13—C14	1.367 (3)
C32—H32B	0.9700	C14—H14	0.9300

C14—C1—C6	120.6 (3)	H33A—C33—H33B	109.5
C14—C1—C2	121.3 (3)	C32—C33—H33C	109.5
C6—C1—C2	118.0 (3)	H33A—C33—H33C	109.5
O2—C2—C3	128.5 (3)	H33B—C33—H33C	109.5
O2—C2—C1	113.7 (3)	N5—C4—C3	126.3 (3)
C3—C2—C1	117.8 (3)	N5—C4—H4	116.8
C2—O2—C21	122.8 (2)	C3—C4—H4	116.8
O2—C21—C22	106.6 (2)	C4—N5—C6	116.2 (3)
O2—C21—H21A	110.4	N5—C6—C1	123.4 (3)
C22—C21—H21A	110.4	N5—C6—C7	119.3 (3)
O2—C21—H21B	110.4	C1—C6—C7	117.3 (3)
C22—C21—H21B	110.4	C8—C7—C6	122.4 (3)
H21A—C21—H21B	108.6	C8—C7—Cl7	119.4 (2)
C21—C22—H22A	109.5	C6—C7—Cl7	118.2 (2)
C21—C22—H22B	109.5	C7—C8—C13	117.4 (3)
H22A—C22—H22B	109.5	C7—C8—C9	125.0 (3)
C21—C22—H22C	109.5	C13—C8—C9	117.5 (3)
H22A—C22—H22C	109.5	C10—C9—C8	120.3 (3)
H22B—C22—H22C	109.5	C10—C9—H9	119.8
C2—C3—C4	118.1 (3)	C8—C9—H9	119.8
C2—C3—C31	124.9 (3)	C9—C10—C11	123.0 (3)
C4—C3—C31	116.6 (3)	C9—C10—H10	118.5
O32—C31—O31	124.3 (3)	C11—C10—H10	118.5
O32—C31—C3	125.5 (3)	O11—C11—O12	117.2 (3)
O31—C31—C3	110.2 (3)	O11—C11—C10	126.8 (3)
C31—O31—C32	117.0 (2)	O12—C11—C10	116.0 (3)
O31—C32—C33	106.2 (2)	C11—O12—C13	122.3 (2)
O31—C32—H32A	110.5	C14—C13—O12	116.2 (3)
C33—C32—H32A	110.5	C14—C13—C8	123.2 (3)
O31—C32—H32B	110.5	O12—C13—C8	120.5 (3)
C33—C32—H32B	110.5	C13—C14—C1	119.0 (3)
H32A—C32—H32B	108.7	C13—C14—H14	120.5
C32—C33—H33A	109.5	C1—C14—H14	120.5
C32—C33—H33B	109.5

C14—C1—C2—O2	−1.5 (4)	C2—C1—C6—C7	−177.2 (3)
C6—C1—C2—O2	177.9 (3)	N5—C6—C7—C8	177.6 (3)
C14—C1—C2—C3	177.8 (3)	C1—C6—C7—C8	−1.2 (4)
C6—C1—C2—C3	−2.8 (4)	N5—C6—C7—Cl7	−2.0 (4)
C3—C2—O2—C21	−31.0 (5)	C1—C6—C7—Cl7	179.2 (2)
C1—C2—O2—C21	148.2 (3)	C6—C7—C8—C13	−0.2 (5)
C2—O2—C21—C22	−154.9 (3)	Cl7—C7—C8—C13	179.4 (2)
O2—C2—C3—C4	179.0 (3)	C6—C7—C8—C9	179.9 (3)
C1—C2—C3—C4	−0.2 (4)	Cl7—C7—C8—C9	−0.5 (4)
O2—C2—C3—C31	−9.4 (5)	C7—C8—C9—C10	177.7 (3)
C1—C2—C3—C31	171.4 (3)	C13—C8—C9—C10	−2.2 (4)
C2—C3—C31—O32	−34.8 (6)	C8—C9—C10—C11	−1.6 (5)
C4—C3—C31—O32	136.9 (4)	C9—C10—C11—O11	−175.1 (4)
C2—C3—C31—O31	148.0 (3)	C9—C10—C11—O12	5.6 (5)
C4—C3—C31—O31	−40.3 (4)	O11—C11—O12—C13	174.6 (3)
O32—C31—O31—C32	−5.9 (5)	C10—C11—O12—C13	−6.1 (4)
C3—C31—O31—C32	171.3 (3)	C11—O12—C13—C14	−176.3 (3)
C31—O31—C32—C33	178.5 (3)	C11—O12—C13—C8	2.6 (4)
C2—C3—C4—N5	2.5 (5)	C7—C8—C13—C14	0.6 (5)
C31—C3—C4—N5	−169.8 (3)	C9—C8—C13—C14	−179.5 (3)
C3—C4—N5—C6	−1.4 (5)	C7—C8—C13—O12	−178.2 (3)
C4—N5—C6—C1	−1.9 (5)	C9—C8—C13—O12	1.7 (4)
C4—N5—C6—C7	179.3 (3)	O12—C13—C14—C1	179.3 (3)
C14—C1—C6—N5	−176.6 (3)	C8—C13—C14—C1	0.4 (5)
C2—C1—C6—N5	4.0 (5)	C6—C1—C14—C13	−1.8 (4)
C14—C1—C6—C7	2.2 (4)	C2—C1—C14—C13	177.6 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9···O11ⁱ	0.93	2.55	3.357 (4)	145
C4—H4···O31	0.93	2.40	2.730 (4)	101
C9—H9···Cl7	0.93	2.71	3.071 (3)	104
C21—H21A···O32	0.97	2.30	2.927 (4)	122

Symmetry code: (i) −x+1, −y, z−1/2.

Acknowledgements

We thank the University of Aberdeen for funding of the X-ray diffractometer, and acknowledge the use of the EPSRC's Chemical Database Service at Daresbury Laboratory (Fletcher et al., 1996 ).

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