Ethyl 3-(3-oxo-3,4-dihydro-quinoxalin-2-yl)propano-ate.

In the title compound, C(13)H(14)N(2)O(3), the fused ring system is almost planar (r.m.s. deviation = 0.015 Å). The r.m.s. deviation for all the non-H atoms of the mol-ecule is 0.065Å. In the crystal, N-H⋯O and C-H⋯O hydrogen bonds generate polymeric chains along the b axis containing alternating centrsymmetric R(2) (2)(8) and R(2) (2)(20) loops.

Related literature

For the synthesis, see: Taylor et al. (1965 ▶). For the biological activity of benzopyrazines, see: Sona et al. (1998 ▶); Cai et al. (1997 ▶); Toshima et al. (2003 ▶); Benbow et al. (2007 ▶); Sarges et al. (1990 ▶); Smits et al. (2008 ▶); Tandon et al. (2006 ▶).

Experimental

Crystal data

C13H14N2O3

M = 246.26

Monoclinic,

a = 8.3138 (6) Å

b = 13.6868 (8) Å

c = 10.8189 (8) Å

β = 102.002 (3)°

V = 1204.16 (14) Å3

Z = 4

Mo Kα radiation

μ = 0.10 mm−1

T = 296 K

0.37 × 0.29 × 0.23 mm

Data collection

Bruker Kappa APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2007 ▶) T min = 0.965, T max = 0.978

11123 measured reflections

2938 independent reflections

1370 reflections with I > 2σ(I)

R int = 0.060

Refinement

R[F 2 > 2σ(F 2)] = 0.068

wR(F 2) = 0.216

S = 0.96

2938 reflections

167 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.44 e Å−3

Δρmin = −0.30 e Å−3

Data collection: APEX2 (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶) and PLATON.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810047094/hb5740sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810047094/hb5740Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C13H14N2O3	F(000) = 520
Mr = 246.26	Dx = 1.358 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1697 reflections
a = 8.3138 (6) Å	θ = 2.8–24.6°
b = 13.6868 (8) Å	µ = 0.10 mm−1
c = 10.8189 (8) Å	T = 296 K
β = 102.002 (3)°	Cut needle, colourless
V = 1204.16 (14) Å3	0.37 × 0.29 × 0.23 mm
Z = 4

Bruker Kappa APEXII CCD diffractometer	2938 independent reflections
Radiation source: fine-focus sealed tube	1370 reflections with I > 2σ(I)
graphite	Rint = 0.060
φ and ω scans	θmax = 28.3°, θmin = 3.5°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −11→11
Tmin = 0.965, Tmax = 0.978	k = −11→18
11123 measured reflections	l = −14→14

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)] = 0.068	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.216	H atoms treated by a mixture of independent and constrained refinement
S = 0.96	w = 1/[σ2(Fo2) + (0.0982P)2 + 0.5331P] where P = (Fo2 + 2Fc2)/3
2938 reflections	(Δ/σ)max < 0.001
167 parameters	Δρmax = 0.44 e Å−3
0 restraints	Δρmin = −0.30 e Å−3

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 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 > 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.

	x	y	z	Uiso*/Ueq
N2	0.5708 (3)	0.81339 (16)	0.0220 (2)	0.0448 (6)
C6	0.3369 (3)	0.70659 (19)	−0.0524 (3)	0.0427 (7)
C1	0.4043 (3)	0.79969 (19)	−0.0334 (3)	0.0436 (7)
C8	0.6615 (3)	0.73747 (19)	0.0532 (3)	0.0423 (7)
C5	0.1719 (4)	0.6942 (2)	−0.1080 (3)	0.0534 (8)
H5	0.1271	0.6318	−0.1199	0.064*
N1	0.4382 (3)	0.62700 (17)	−0.0166 (2)	0.0478 (7)
O3	1.1357 (2)	0.94521 (16)	0.1990 (3)	0.0763 (8)
C7	0.5997 (3)	0.63615 (19)	0.0353 (3)	0.0448 (7)
C2	0.3048 (3)	0.8807 (2)	−0.0717 (3)	0.0518 (8)
H2	0.3487	0.9433	−0.0600	0.062*
C9	0.8402 (3)	0.7474 (2)	0.1117 (3)	0.0485 (8)
H9A	0.9034	0.7137	0.0589	0.058*
H9B	0.8613	0.7151	0.1933	0.058*
C10	0.9003 (3)	0.8516 (2)	0.1298 (3)	0.0503 (8)
H10A	0.8863	0.8834	0.0481	0.060*
H10B	0.8348	0.8868	0.1797	0.060*
O1	0.6900 (2)	0.56381 (14)	0.0636 (2)	0.0593 (7)
C11	1.0773 (4)	0.8557 (2)	0.1947 (3)	0.0563 (9)
O2	1.1589 (3)	0.78799 (19)	0.2404 (3)	0.0934 (10)
C3	0.1417 (4)	0.8677 (2)	−0.1268 (3)	0.0591 (9)
H3	0.0754	0.9219	−0.1518	0.071*
C12	1.3079 (4)	0.9554 (3)	0.2601 (4)	0.0911 (14)
H12A	1.3271	0.9249	0.3428	0.109*
H12B	1.3760	0.9226	0.2102	0.109*
C4	0.0752 (4)	0.7746 (2)	−0.1455 (3)	0.0577 (9)
H4	−0.0351	0.7667	−0.1834	0.069*
C13	1.3500 (6)	1.0526 (4)	0.2726 (6)	0.131 (2)
H13C	1.3410	1.0811	0.1904	0.196*
H13A	1.4611	1.0587	0.3193	0.196*
H13B	1.2773	1.0858	0.3169	0.196*
H1N	0.394 (6)	0.562 (5)	−0.033 (5)	0.157*

	U11	U22	U33	U12	U13	U23
N2	0.0344 (13)	0.0382 (13)	0.0576 (16)	−0.0021 (10)	−0.0004 (11)	0.0004 (11)
C6	0.0340 (15)	0.0374 (15)	0.0542 (18)	0.0006 (12)	0.0034 (13)	0.0025 (13)
C1	0.0362 (16)	0.0384 (16)	0.0526 (18)	0.0021 (12)	0.0010 (13)	0.0010 (13)
C8	0.0357 (15)	0.0362 (15)	0.0507 (17)	0.0023 (11)	−0.0009 (13)	0.0001 (13)
C5	0.0374 (17)	0.0458 (18)	0.073 (2)	−0.0046 (13)	0.0014 (15)	−0.0021 (15)
N1	0.0332 (13)	0.0357 (13)	0.0680 (17)	−0.0008 (10)	−0.0049 (11)	0.0009 (11)
O3	0.0340 (12)	0.0536 (14)	0.127 (2)	−0.0050 (10)	−0.0155 (12)	−0.0091 (14)
C7	0.0396 (16)	0.0347 (15)	0.0564 (19)	−0.0002 (12)	0.0015 (14)	−0.0025 (13)
C2	0.0428 (18)	0.0371 (16)	0.071 (2)	0.0018 (12)	0.0008 (15)	0.0003 (14)
C9	0.0339 (16)	0.0423 (16)	0.065 (2)	0.0019 (12)	−0.0004 (14)	−0.0012 (14)
C10	0.0336 (16)	0.0424 (17)	0.069 (2)	0.0006 (12)	−0.0035 (14)	0.0018 (15)
O1	0.0428 (12)	0.0353 (11)	0.0905 (17)	0.0076 (9)	−0.0075 (11)	−0.0010 (10)
C11	0.0356 (16)	0.052 (2)	0.074 (2)	0.0011 (14)	−0.0057 (15)	−0.0044 (16)
O2	0.0467 (15)	0.0687 (17)	0.143 (3)	0.0075 (12)	−0.0295 (15)	0.0194 (16)
C3	0.0420 (18)	0.0458 (18)	0.083 (2)	0.0102 (14)	−0.0017 (16)	0.0066 (16)
C12	0.038 (2)	0.081 (3)	0.138 (4)	−0.0081 (18)	−0.020 (2)	−0.014 (3)
C4	0.0324 (16)	0.055 (2)	0.081 (2)	0.0031 (13)	0.0010 (15)	0.0037 (17)
C13	0.078 (3)	0.088 (4)	0.207 (6)	−0.031 (3)	−0.015 (3)	−0.020 (4)

N2—C8	1.287 (3)	C9—C10	1.511 (4)
N2—C1	1.402 (3)	C9—H9A	0.9700
C6—N1	1.382 (3)	C9—H9B	0.9700
C6—C5	1.389 (4)	C10—C11	1.494 (4)
C6—C1	1.390 (4)	C10—H10A	0.9700
C1—C2	1.394 (4)	C10—H10B	0.9700
C8—C7	1.478 (4)	C11—O2	1.193 (4)
C8—C9	1.495 (4)	C3—C4	1.387 (4)
C5—C4	1.373 (4)	C3—H3	0.9300
C5—H5	0.9300	C12—C13	1.375 (6)
N1—C7	1.349 (3)	C12—H12A	0.9700
N1—H1N	0.96 (6)	C12—H12B	0.9700
O3—C11	1.316 (4)	C4—H4	0.9300
O3—C12	1.453 (4)	C13—H13C	0.9600
C7—O1	1.242 (3)	C13—H13A	0.9600
C2—C3	1.375 (4)	C13—H13B	0.9600
C2—H2	0.9300
C8—N2—C1	118.5 (2)	H9A—C9—H9B	107.6
N1—C6—C5	121.0 (2)	C11—C10—C9	111.3 (2)
N1—C6—C1	118.5 (2)	C11—C10—H10A	109.4
C5—C6—C1	120.5 (3)	C9—C10—H10A	109.4
C6—C1—C2	119.3 (3)	C11—C10—H10B	109.4
C6—C1—N2	121.2 (2)	C9—C10—H10B	109.4
C2—C1—N2	119.5 (2)	H10A—C10—H10B	108.0
N2—C8—C7	123.6 (3)	O2—C11—O3	122.4 (3)
N2—C8—C9	121.0 (2)	O2—C11—C10	125.8 (3)
C7—C8—C9	115.4 (2)	O3—C11—C10	111.8 (3)
C4—C5—C6	119.7 (3)	C2—C3—C4	120.6 (3)
C4—C5—H5	120.2	C2—C3—H3	119.7
C6—C5—H5	120.2	C4—C3—H3	119.7
C7—N1—C6	122.6 (2)	C13—C12—O3	110.1 (4)
C7—N1—H1N	118 (3)	C13—C12—H12A	109.6
C6—N1—H1N	119 (3)	O3—C12—H12A	109.6
C11—O3—C12	115.2 (3)	C13—C12—H12B	109.6
O1—C7—N1	121.8 (2)	O3—C12—H12B	109.6
O1—C7—C8	122.7 (3)	H12A—C12—H12B	108.2
N1—C7—C8	115.5 (2)	C5—C4—C3	120.1 (3)
C3—C2—C1	119.8 (3)	C5—C4—H4	119.9
C3—C2—H2	120.1	C3—C4—H4	119.9
C1—C2—H2	120.1	C12—C13—H13C	109.5
C8—C9—C10	114.4 (2)	C12—C13—H13A	109.5
C8—C9—H9A	108.7	H13C—C13—H13A	109.5
C10—C9—H9A	108.7	C12—C13—H13B	109.5
C8—C9—H9B	108.7	H13C—C13—H13B	109.5
C10—C9—H9B	108.7	H13A—C13—H13B	109.5
N1—C6—C1—C2	178.5 (3)	N2—C8—C7—N1	−0.2 (4)
C5—C6—C1—C2	−0.4 (5)	C9—C8—C7—N1	179.5 (3)
N1—C6—C1—N2	−0.8 (4)	C6—C1—C2—C3	0.4 (5)
C5—C6—C1—N2	−179.7 (3)	N2—C1—C2—C3	179.6 (3)
C8—N2—C1—C6	1.3 (4)	N2—C8—C9—C10	0.1 (4)
C8—N2—C1—C2	−177.9 (3)	C7—C8—C9—C10	−179.6 (3)
C1—N2—C8—C7	−0.8 (4)	C8—C9—C10—C11	177.0 (3)
C1—N2—C8—C9	179.5 (3)	C12—O3—C11—O2	1.7 (5)
N1—C6—C5—C4	−178.4 (3)	C12—O3—C11—C10	−179.6 (3)
C1—C6—C5—C4	0.5 (5)	C9—C10—C11—O2	−8.1 (5)
C5—C6—N1—C7	178.6 (3)	C9—C10—C11—O3	173.2 (3)
C1—C6—N1—C7	−0.3 (4)	C1—C2—C3—C4	−0.4 (5)
C6—N1—C7—O1	−177.9 (3)	C11—O3—C12—C13	−172.8 (4)
C6—N1—C7—C8	0.8 (4)	C6—C5—C4—C3	−0.5 (5)
N2—C8—C7—O1	178.5 (3)	C2—C3—C4—C5	0.5 (5)
C9—C8—C7—O1	−1.8 (4)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O1i	0.96 (6)	1.87 (6)	2.827 (3)	179 (5)
C3—H3···O3ii	0.93	2.51	3.426 (4)	170

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯O1i	0.96 (6)	1.87 (6)	2.827 (3)	179 (5)
C3—H3⋯O3ii	0.93	2.51	3.426 (4)	170

Symmetry codes: (i) ; (ii) .