6-Acetyl-2-(N-methyl­amido)pyridine

In the title crystal structure, C₉H₁₀N₂O₂, a weak N—H...O hydrogen bond between the amide group of the methyl­amide substituent and the acetyl substituent of an adjacent mol­ecule gives rise to a helical chain which propagates along the c-axis direction of the ortho­rhom­bic unit cell. The mol­ecule is essentially flat.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.046
• wR factor = 0.165
• Data-to-parameter ratio = 8.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          6

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.00
           From the CIF: _reflns_number_total               1061
           Count of symmetry unique reflns         1070
           Completeness (_total/calc)             99.16%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no

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

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

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Computing details

Data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

6-Acetyl-2-(N-methylamido)pyridine

Crystal data

C9H10N2O2	F(000) = 376
Mr = 178.19	Dx = 1.289 Mg m^−3
Orthorhombic, Pca21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2ac	Cell parameters from 756 reflections
a = 22.784 (1) Å	θ = 2.8–21.3°
b = 4.3504 (2) Å	µ = 0.09 mm^−1
c = 9.2672 (6) Å	T = 295 K
V = 918.56 (8) Å^3	Block, colorless
Z = 4	0.40 × 0.19 × 0.18 mm

Data collection

Bruker APEX-II area-detector diffractometer	621 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.036
Graphite monochromator	θmax = 27.0°, θmin = 2.8°
Detector resolution: 8.33 pixels mm^-1	h = −29→20
φ and ω scans	k = −5→5
4164 measured reflections	l = −9→11
1061 independent reflections

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.165	H-atom parameters constrained
S = 0.96	w = 1/[σ^2(Fo^2) + (0.1074P)^2] where P = (Fo^2 + 2Fc^2)/3
1061 reflections	(Δ/σ)max = 0.001
121 parameters	Δρmax = 0.13 e Å^−3
1 restraint	Δρmin = −0.18 e Å^−3

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

	x	y	z	Uiso*/Ueq
O1	0.5064 (1)	0.6145 (9)	0.5000 (5)	0.100 (1)
O2	0.2708 (1)	1.4075 (8)	0.1895 (4)	0.105 (1)
N1	0.4020 (1)	1.0499 (7)	0.3084 (4)	0.062 (1)
N2	0.3606 (2)	1.4110 (8)	0.0929 (4)	0.075 (1)
C1	0.5200 (2)	0.890 (1)	0.2873 (6)	0.086 (1)
C2	0.4854 (2)	0.777 (1)	0.4059 (5)	0.070 (1)
C3	0.4212 (2)	0.8672 (8)	0.4132 (4)	0.063 (1)
C4	0.3856 (2)	0.763 (1)	0.5245 (5)	0.078 (1)
C5	0.3296 (2)	0.849 (1)	0.5283 (5)	0.091 (2)
C6	0.3083 (2)	1.034 (1)	0.4200 (6)	0.084 (1)
C7	0.3451 (2)	1.1315 (9)	0.3128 (5)	0.067 (1)
C8	0.3216 (2)	1.3288 (9)	0.1930 (5)	0.071 (1)
C9	0.3439 (2)	1.599 (1)	−0.0310 (7)	0.092 (2)
H2n	0.3965	1.3519	0.1015	0.090*
H1a	0.5583	0.7985	0.2902	0.129*
H1b	0.5237	1.1097	0.2947	0.129*
H1c	0.5012	0.8388	0.1978	0.129*
H4	0.4007	0.6335	0.5953	0.094*
H5	0.3052	0.7856	0.6031	0.110*
H6	0.2691	1.0933	0.4197	0.101*
H9a	0.3785	1.6806	−0.0760	0.137*
H9b	0.3194	1.7655	0.0008	0.137*
H9c	0.3227	1.4753	−0.0992	0.137*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.076 (2)	0.139 (3)	0.086 (2)	0.017 (2)	−0.005 (2)	0.025 (2)
O2	0.058 (2)	0.141 (3)	0.115 (3)	0.025 (2)	−0.010 (2)	0.015 (3)
N1	0.053 (2)	0.067 (2)	0.065 (2)	0.001 (1)	−0.006 (2)	−0.008 (2)
N2	0.065 (2)	0.077 (2)	0.083 (2)	0.009 (2)	−0.006 (2)	0.002 (2)
C1	0.068 (3)	0.097 (3)	0.092 (3)	0.016 (2)	0.006 (3)	0.005 (3)
C2	0.060 (2)	0.082 (3)	0.067 (3)	0.004 (2)	−0.002 (2)	−0.007 (2)
C3	0.056 (2)	0.070 (2)	0.064 (2)	−0.002 (2)	−0.010 (2)	−0.009 (2)
C4	0.058 (2)	0.101 (3)	0.075 (3)	−0.012 (2)	−0.008 (2)	0.010 (3)
C5	0.074 (3)	0.111 (4)	0.089 (4)	−0.018 (2)	0.009 (3)	0.009 (3)
C6	0.059 (2)	0.100 (3)	0.094 (3)	−0.003 (2)	0.004 (3)	−0.002 (3)
C7	0.052 (2)	0.075 (2)	0.076 (3)	−0.004 (2)	−0.001 (2)	−0.013 (2)
C8	0.055 (2)	0.079 (3)	0.079 (3)	0.002 (2)	−0.007 (2)	−0.013 (2)
C9	0.091 (3)	0.091 (4)	0.093 (4)	0.008 (3)	−0.005 (3)	0.011 (3)

Geometric parameters (Å, º)

O1—C2	1.219 (6)	C7—C8	1.502 (6)
O2—C8	1.207 (5)	N2—H2n	0.86
N1—C3	1.329 (5)	C1—H1a	0.96
N1—C7	1.345 (5)	C1—H1b	0.96
N2—C8	1.334 (6)	C1—H1c	0.96
N2—C9	1.461 (7)	C4—H4	0.93
C1—C2	1.441 (7)	C5—H5	0.93
C2—C3	1.517 (5)	C6—H6	0.93
C3—C4	1.388 (6)	C9—H9a	0.96
C4—C5	1.331 (6)	C9—H9b	0.96
C5—C6	1.376 (7)	C9—H9c	0.96
C6—C7	1.367 (7)
C3—N1—C7	116.9 (3)	H1a—C1—H1c	109.5
C8—N2—C9	121.5 (4)	H1b—C1—H1c	109.5
O1—C2—C1	122.0 (4)	C5—C4—H4	120.5
O1—C2—C3	119.8 (4)	C3—C4—H4	120.5
C1—C2—C3	118.2 (4)	C4—C5—H5	120.5
N1—C3—C4	123.2 (4)	C6—C5—H5	120.5
N1—C3—C2	116.1 (4)	C8—N2—H2n	119.2
C4—C3—C2	120.7 (4)	C9—N2—H2n	119.2
C5—C4—C3	119.1 (4)	C2—C1—H1A	109.5
C4—C5—C6	119.0 (4)	C2—C1—H1B	109.5
C7—C6—C5	119.7 (4)	C7—C6—H6	120.1
N1—C7—C6	122.1 (4)	C5—C6—H6	120.1
N1—C7—C8	118.2 (3)	N2—C9—H9a	109.5
C6—C7—C8	119.7 (4)	N2—C9—H9b	109.5
O2—C8—N2	123.0 (4)	H9a—C9—H9b	109.5
O2—C8—C7	121.6 (4)	N2—C9—H9c	109.5
N2—C8—C7	115.5 (3)	H9a—C9—H9c	109.5
H1a—C1—H1b	109.5	H9b—C9—H9c	109.5
C2—C1—H1c	109.5
C7—N1—C3—C4	−0.5 (5)	C3—N1—C7—C6	0.5 (5)
C7—N1—C3—C2	179.7 (3)	C3—N1—C7—C8	−177.9 (3)
O1—C2—C3—N1	178.5 (4)	C5—C6—C7—N1	0.5 (7)
C1—C2—C3—N1	−0.7 (6)	C5—C6—C7—C8	178.8 (4)
O1—C2—C3—C4	−1.3 (6)	C9—N2—C8—O2	−1.4 (6)
C1—C2—C3—C4	179.5 (4)	C9—N2—C8—C7	179.2 (4)
N1—C3—C4—C5	−0.5 (7)	N1—C7—C8—O2	179.2 (4)
C2—C3—C4—C5	179.3 (4)	C6—C7—C8—O2	0.8 (6)
C3—C4—C5—C6	1.5 (7)	N1—C7—C8—N2	−1.3 (5)
C4—C5—C6—C7	−1.5 (7)	C6—C7—C8—N2	−179.7 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2n···O1^i	0.86	2.41	3.152 (5)	145

Symmetry code: (i) −x+1, −y+2, z−1/2.