Ethyl 4-oxo-1,4-di­hydro­pyridine-3-carboxyl­ate

The title compound, C₈H₉NO₃, likely generated through hydrolysis and esterification of 3′-carb­oxy-3-methyl-(1,4′-bipyridin)-1-ium chloride by ethanol, which contained water, has a nearly planar conformation. The crystal structure is sustained by one-dimensional chains along the a-axis direction based on bifurcated N—H...(O,O) hydrogen bonds between the NH group of the 4-oxo-1,4-di­hydro­pyridine ring and the two carbonyl O atoms.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.046
• wR factor = 0.129
• Data-to-parameter ratio = 14.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT761_ALERT_1_C CIF Contains no X-H Bonds ......................     Please Check
PLAT762_ALERT_1_C CIF Contains no X-Y-H or H-Y-H Angles ..........     Please Check
PLAT906_ALERT_3_C Large K Value in the Analysis of Variance ......      2.608 Check
PLAT911_ALERT_3_C Missing FCF Refl Between Thmin & STh/L=    0.600         18 Report
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          5 Note

Alert level G
PLAT199_ALERT_1_G Reported _cell_measurement_temperature ..... (K)        293 Check
PLAT200_ALERT_1_G Reported   _diffrn_ambient_temperature ..... (K)        293 Check
PLAT432_ALERT_2_G Short Inter X...Y Contact  O1       ..C4               3.00 Ang.
                                                    1+x,y,z  =      1_655 Check
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Theta(Min).          1 Note
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         85 Note
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          5 Info

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   5 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   6 ALERT level G = General information/check it is not something unexpected

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: CrysAlis PRO (Rigaku OD, 2020); cell refinement: CrysAlis PRO (Rigaku OD, 2020); data reduction: CrysAlis PRO (Rigaku OD, 2020); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2020); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Ethyl 4-oxo-1,4-dihydropyridine-3-carboxylate

Crystal data

C8H9NO3	F(000) = 352
Mr = 167.16	Dx = 1.313 Mg m^−3
Monoclinic, P21/c	Cu Kα radiation, λ = 1.54184 Å
a = 6.4973 (2) Å	Cell parameters from 3630 reflections
b = 11.5323 (5) Å	θ = 6.8–76.4°
c = 11.2908 (5) Å	µ = 0.86 mm^−1
β = 91.500 (4)°	T = 293 K
V = 845.72 (6) Å^3	Needle, clear light colourless
Z = 4	0.07 × 0.03 × 0.02 mm

Data collection

Rigaku Oxford Diffraction, Synergy Custom system, HyPix diffractometer	1693 independent reflections
Radiation source: Rotating-anode X-ray tube, Rigaku (Cu) X-ray Source	1456 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.022
Detector resolution: 10.0000 pixels mm^-1	θmax = 77.4°, θmin = 6.8°
ω scans	h = −8→7
Absorption correction: multi-scan (CrysAlisPro; Rigaku OD, 2020)	k = −14→5
Tmin = 0.311, Tmax = 1.000	l = −13→14
5379 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: mixed
R[F^2 > 2σ(F^2)] = 0.046	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.129	w = 1/[σ^2(Fo^2) + (0.0674P)^2 + 0.1472P] where P = (Fo^2 + 2Fc^2)/3
S = 1.11	(Δ/σ)max < 0.001
1693 reflections	Δρmax = 0.21 e Å^−3
114 parameters	Δρmin = −0.22 e Å^−3
0 restraints

Special details

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

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

	x	y	z	Uiso*/Ueq
O1	0.52166 (14)	0.40585 (10)	0.20366 (11)	0.0600 (4)
O2	0.57531 (15)	0.62403 (10)	0.09977 (11)	0.0584 (4)
O3	0.28325 (16)	0.71651 (9)	0.05152 (11)	0.0555 (3)
N1	−0.08871 (17)	0.47182 (12)	0.17157 (11)	0.0471 (3)
C1	0.25305 (18)	0.53513 (12)	0.14051 (12)	0.0388 (3)
C2	0.33512 (19)	0.42840 (13)	0.19022 (13)	0.0436 (4)
C3	0.1821 (2)	0.34638 (14)	0.22568 (15)	0.0538 (4)
H3	0.224295	0.274979	0.255937	0.065*
C4	−0.0203 (2)	0.36993 (15)	0.21635 (15)	0.0517 (4)
H4	−0.114786	0.315080	0.241186	0.062*
C5	0.04315 (19)	0.55121 (13)	0.13385 (13)	0.0421 (3)
H5	−0.008399	0.619967	0.101877	0.051*
C6	0.3901 (2)	0.62675 (12)	0.09660 (13)	0.0421 (3)
C7	0.3996 (3)	0.81144 (16)	0.00264 (19)	0.0663 (5)
H7A	0.470155	0.786241	−0.067519	0.080*
H7B	0.501453	0.839160	0.060290	0.080*
C8	0.2495 (4)	0.90531 (19)	−0.0281 (2)	0.0899 (7)
H8A	0.317924	0.965688	−0.070384	0.135*
H8B	0.194250	0.936516	0.043203	0.135*
H8C	0.139659	0.874119	−0.076909	0.135*
H1	−0.224 (3)	0.4880 (17)	0.1645 (17)	0.071 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0234 (5)	0.0609 (7)	0.0956 (9)	0.0027 (4)	0.0007 (5)	0.0191 (6)
O2	0.0296 (5)	0.0541 (7)	0.0918 (9)	−0.0041 (4)	0.0038 (5)	0.0110 (6)
O3	0.0411 (6)	0.0456 (6)	0.0799 (8)	0.0017 (4)	0.0029 (5)	0.0130 (5)
N1	0.0211 (5)	0.0596 (8)	0.0608 (7)	−0.0002 (5)	0.0018 (5)	0.0002 (6)
C1	0.0255 (6)	0.0448 (8)	0.0460 (7)	0.0000 (5)	0.0022 (5)	−0.0028 (6)
C2	0.0241 (6)	0.0512 (8)	0.0555 (8)	−0.0001 (5)	0.0018 (5)	0.0018 (6)
C3	0.0321 (7)	0.0519 (9)	0.0774 (11)	−0.0012 (6)	0.0020 (7)	0.0147 (8)
C4	0.0288 (7)	0.0588 (9)	0.0678 (10)	−0.0075 (6)	0.0045 (6)	0.0075 (7)
C5	0.0279 (6)	0.0467 (8)	0.0517 (8)	0.0028 (5)	0.0006 (5)	−0.0024 (6)
C6	0.0307 (6)	0.0423 (7)	0.0532 (8)	0.0010 (5)	0.0016 (5)	−0.0022 (6)
C7	0.0674 (11)	0.0478 (9)	0.0842 (12)	−0.0088 (8)	0.0079 (9)	0.0110 (8)
C8	0.1063 (19)	0.0616 (13)	0.1014 (17)	0.0040 (11)	−0.0053 (14)	0.0288 (11)

Geometric parameters (Å, º)

O1—C2	1.2450 (16)	C1—C2	1.449 (2)
O2—C6	1.2032 (16)	C1—C5	1.3765 (17)
O3—C6	1.3395 (17)	C1—C6	1.4760 (19)
O3—C7	1.448 (2)	C2—C3	1.437 (2)
N1—C4	1.350 (2)	C3—C4	1.344 (2)
N1—C5	1.3314 (19)	C7—C8	1.492 (3)
C6—O3—C7	117.28 (12)	C4—C3—C2	121.85 (15)
C5—N1—C4	120.66 (12)	C3—C4—N1	121.15 (14)
C2—C1—C6	121.28 (11)	N1—C5—C1	122.33 (13)
C5—C1—C2	119.33 (12)	O2—C6—O3	122.66 (13)
C5—C1—C6	119.40 (12)	O2—C6—C1	125.66 (13)
O1—C2—C1	124.89 (13)	O3—C6—C1	111.68 (11)
O1—C2—C3	120.46 (14)	O3—C7—C8	107.00 (16)
C3—C2—C1	114.65 (12)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^i	0.90 (2)	1.96 (2)	2.6771 (15)	134.9 (17)
N1—H1···O2^i	0.90 (2)	2.15 (2)	2.9002 (17)	139.6 (17)

Symmetry code: (i) x−1, y, z.