4,6-Di­methyl-5-nitro-1H-pyridin-2-one

In the crystal structure of the title compound, C₇H₈N₂O₃, mol­ecules form centrosymmetrical dimers via N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.043
• wR factor = 0.111
• Data-to-parameter ratio = 12.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    N5     -   C5       =       6.45 su

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

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

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Computing details

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLUTON97 (Spek, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

4,6-Dimethyl-5-nitro-1H-pyridin-2-one

Crystal data

C7H8N2O3	F(000) = 352
Mr = 168.15	Dx = 1.443 Mg m^−3
Monoclinic, P21/n	Melting point: 518 K
Hall symbol: -P 2yn	Cu Kα radiation, λ = 1.5418 Å
a = 9.7677 (15) Å	Cell parameters from 25 reflections
b = 5.875 (3) Å	θ = 28–31°
c = 13.7295 (15) Å	µ = 0.98 mm^−1
β = 100.76 (1)°	T = 293 K
V = 774.0 (4) Å^3	Needle, colourless
Z = 4	0.3 × 0.1 × 0.03 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.037
Radiation source: fine-focus sealed tube	θmax = 69.9°, θmin = 5.1°
Graphite monochromator	h = −11→11
non–profiled ω scans	k = 0→7
1524 measured reflections	l = 0→16
1462 independent reflections	1 standard reflections every 200 reflections
999 reflections with I > 2σ(I)	intensity decay: none

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.111	H atoms treated by a mixture of independent and constrained refinement
S = 0.98	w = 1/[σ^2(Fo^2) + (0.0554P)^2] where P = (Fo^2 + 2Fc^2)/3
1462 reflections	(Δ/σ)max < 0.001
113 parameters	Δρmax = 0.13 e Å^−3
0 restraints	Δρmin = −0.15 e Å^−3

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

	x	y	z	Uiso*/Ueq
N1	0.42744 (16)	0.2535 (3)	0.54759 (12)	0.0423 (4)
H1	0.409 (2)	0.149 (3)	0.5053 (16)	0.038 (6)*
C2	0.5533 (2)	0.2301 (4)	0.61175 (15)	0.0453 (5)
O2	0.63546 (15)	0.0769 (3)	0.59845 (12)	0.0605 (5)
C3	0.5763 (2)	0.3920 (4)	0.69052 (15)	0.0471 (5)
H3	0.6599	0.3861	0.7358	0.056*
C4	0.48220 (19)	0.5537 (4)	0.70259 (14)	0.0434 (5)
C41	0.5126 (2)	0.7113 (4)	0.78987 (17)	0.0579 (6)
H41A	0.5935	0.6587	0.8350	0.087*
H41B	0.4343	0.7143	0.8230	0.087*
H41C	0.5294	0.8618	0.7675	0.087*
C5	0.35407 (19)	0.5590 (3)	0.63226 (15)	0.0414 (5)
N5	0.25012 (18)	0.7322 (3)	0.63966 (13)	0.0507 (5)
O51	0.29106 (18)	0.9246 (3)	0.66441 (15)	0.0732 (6)
O52	0.12725 (17)	0.6816 (3)	0.62211 (15)	0.0770 (6)
C6	0.32700 (18)	0.4046 (3)	0.55577 (14)	0.0404 (5)
C61	0.1974 (2)	0.3875 (4)	0.47778 (16)	0.0553 (6)
H61A	0.2194	0.3168	0.4196	0.083*
H61B	0.1608	0.5372	0.4614	0.083*
H61C	0.1292	0.2976	0.5025	0.083*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0472 (9)	0.0433 (10)	0.0360 (9)	−0.0007 (8)	0.0065 (7)	−0.0077 (8)
C2	0.0443 (9)	0.0500 (13)	0.0418 (11)	0.0007 (10)	0.0089 (8)	−0.0035 (10)
O2	0.0526 (8)	0.0650 (11)	0.0604 (10)	0.0147 (8)	0.0011 (7)	−0.0190 (8)
C3	0.0472 (10)	0.0532 (14)	0.0396 (11)	−0.0010 (10)	0.0049 (8)	−0.0062 (10)
C4	0.0470 (10)	0.0457 (12)	0.0392 (11)	−0.0057 (9)	0.0124 (8)	−0.0032 (9)
C41	0.0642 (13)	0.0574 (15)	0.0502 (13)	−0.0001 (12)	0.0061 (10)	−0.0162 (12)
C5	0.0447 (9)	0.0393 (11)	0.0425 (11)	0.0004 (9)	0.0140 (8)	0.0006 (9)
N5	0.0537 (10)	0.0472 (11)	0.0533 (11)	−0.0009 (9)	0.0155 (8)	−0.0002 (9)
O51	0.0757 (11)	0.0493 (10)	0.0957 (15)	0.0033 (9)	0.0189 (10)	−0.0044 (10)
O52	0.0535 (9)	0.0799 (13)	0.0984 (15)	0.0047 (9)	0.0163 (9)	−0.0117 (11)
C6	0.0434 (9)	0.0404 (11)	0.0382 (11)	−0.0004 (9)	0.0098 (8)	0.0048 (9)
C61	0.0525 (11)	0.0633 (16)	0.0473 (13)	0.0037 (11)	0.0023 (9)	−0.0030 (11)

Geometric parameters (Å, º)

N1—C6	1.343 (2)	C41—H41B	0.96
N1—C2	1.379 (2)	C41—H41C	0.96
N1—H1	0.84 (2)	C5—C6	1.375 (3)
C2—O2	1.242 (2)	C5—N5	1.454 (3)
C2—C3	1.426 (3)	N5—O52	1.216 (2)
C3—C4	1.353 (3)	N5—O51	1.226 (2)
C3—H3	0.93	C6—C61	1.501 (3)
C4—C5	1.431 (3)	C61—H61A	0.96
C4—C41	1.499 (3)	C61—H61B	0.96
C41—H41A	0.96	C61—H61C	0.96
C6—N1—C2	126.17 (19)	H41B—C41—H41C	109.5
C6—N1—H1	118.4 (13)	C6—C5—C4	121.33 (18)
C2—N1—H1	114.7 (13)	C6—C5—N5	118.52 (17)
O2—C2—N1	120.11 (19)	C4—C5—N5	120.14 (18)
O2—C2—C3	125.47 (18)	O52—N5—O51	122.6 (2)
N1—C2—C3	114.41 (19)	O52—N5—C5	119.40 (19)
C4—C3—C2	123.15 (19)	O51—N5—C5	117.95 (18)
C4—C3—H3	118.4	N1—C6—C5	117.41 (17)
C2—C3—H3	118.4	N1—C6—C61	115.33 (18)
C3—C4—C5	117.44 (19)	C5—C6—C61	127.25 (18)
C3—C4—C41	119.59 (18)	C6—C61—H61A	109.5
C5—C4—C41	122.91 (19)	C6—C61—H61B	109.5
C4—C41—H41A	109.5	H61A—C61—H61B	109.5
C4—C41—H41B	109.5	C6—C61—H61C	109.5
H41A—C41—H41B	109.5	H61A—C61—H61C	109.5
C4—C41—H41C	109.5	H61B—C61—H61C	109.5
H41A—C41—H41C	109.5

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O2^i	0.84 (2)	1.94 (2)	2.776 (2)	176 (2)
C61—H61B···O52	0.96	2.44	2.809 (3)	102

Symmetry code: (i) −x+1, −y, −z+1.