N,N′-Bis(pyridin-2-yl)octa­nedi­amide

The complete mol­ecule of the title compound, C₁₈H₂₂N₄O₂, is generated by crystallographic inversion symmetry. In the crystal, N—H...N hydrogen bonds connect the mol­ecules into [010] chains, which feature R₂²(8) loops. The packing is consolidated by C—H...O inter­actions.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.032
• wR factor = 0.073
• Data-to-parameter ratio = 13.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT018_ALERT_1_C _diffrn_measured_fraction_theta_max .NE. *_full           ! Check
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......      2.534 Check

Alert level G
PLAT007_ALERT_5_G Number of Unrefined Donor-H Atoms ..............          1 Report
PLAT909_ALERT_3_G Percentage of Observed Data at Theta(Max) Still          57 %
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Theta(Min)           3 Note
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density           1 Note

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

   1 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
   3 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

---

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell refinement: CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: SHELXL2013 (Sheldrick, 2015); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2015).

N,N'-Bis(pyridin-2-yl)octanediamide

Crystal data

C18H22N4O2	F(000) = 696
Mr = 326.39	Dx = 1.278 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 11.9289 (7) Å	Cell parameters from 5224 reflections
b = 13.2908 (6) Å	θ = 3.5–25.2°
c = 11.5000 (6) Å	µ = 0.09 mm^−1
β = 111.497 (7)°	T = 100 K
V = 1696.43 (17) Å^3	Irregular, colourless
Z = 4	0.25 × 0.23 × 0.18 mm

Data collection

Oxford Diffraction Xcalibur diffractometer	1125 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.024
Graphite monochromator	θmax = 25.0°, θmin = 3.5°
Detector resolution: 1024 x 1024 with blocks 2 x 2 pixels mm^-1	h = −14→13
ω–scan	k = −15→15
5224 measured reflections	l = −13→13
1494 independent reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.032	H-atom parameters constrained
wR(F^2) = 0.073	w = 1/[σ^2(Fo^2) + (0.0429P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.95	(Δ/σ)max < 0.001
1494 reflections	Δρmax = 0.24 e Å^−3
110 parameters	Δρmin = −0.15 e Å^−3
0 restraints	Extinction correction: SHELXL2013 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0012 (3)

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	0.15817 (8)	0.27316 (7)	0.84143 (8)	0.0259 (3)
N1	0.10057 (9)	0.57410 (8)	0.92312 (10)	0.0228 (3)
N2	0.08189 (9)	0.40263 (7)	0.92055 (10)	0.0189 (3)
H2A	0.0393	0.4149	0.9652	0.023*
C1	0.12421 (10)	0.48726 (9)	0.87675 (11)	0.0177 (3)
C2	0.18323 (11)	0.48219 (10)	0.79260 (12)	0.0213 (3)
H2	0.1975	0.4206	0.7621	0.026*
C3	0.21992 (11)	0.57095 (10)	0.75567 (13)	0.0238 (3)
H3	0.2594	0.5699	0.6994	0.029*
C4	0.19788 (11)	0.66159 (10)	0.80261 (12)	0.0235 (3)
H4	0.2225	0.7223	0.7795	0.028*
C5	0.13834 (11)	0.65855 (9)	0.88437 (13)	0.0253 (3)
H5	0.1229	0.7195	0.9154	0.030*
C6	0.09926 (11)	0.30281 (9)	0.90189 (11)	0.0184 (3)
C7	0.03884 (11)	0.23330 (9)	0.96366 (11)	0.0196 (3)
H7A	−0.0464	0.2492	0.9333	0.023*
H7B	0.0713	0.2462	1.0529	0.023*
C8	0.05278 (11)	0.12258 (9)	0.94244 (12)	0.0203 (3)
H8A	0.1378	0.1071	0.9668	0.024*
H8B	0.0141	0.1080	0.8540	0.024*
C9	−0.00115 (12)	0.05536 (9)	1.01516 (12)	0.0196 (3)
H9A	0.0430	0.0652	1.1038	0.023*
H9B	−0.0839	0.0756	0.9973	0.023*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0303 (5)	0.0225 (5)	0.0322 (6)	0.0020 (4)	0.0199 (5)	−0.0011 (4)
N1	0.0243 (6)	0.0180 (6)	0.0279 (7)	−0.0012 (5)	0.0117 (5)	0.0013 (5)
N2	0.0216 (6)	0.0172 (6)	0.0227 (6)	0.0009 (5)	0.0138 (5)	0.0007 (5)
C1	0.0144 (6)	0.0184 (7)	0.0180 (7)	−0.0003 (5)	0.0032 (5)	0.0028 (5)
C2	0.0187 (7)	0.0242 (7)	0.0215 (7)	0.0010 (6)	0.0080 (6)	0.0004 (6)
C3	0.0176 (7)	0.0335 (8)	0.0211 (7)	−0.0009 (6)	0.0081 (6)	0.0057 (6)
C4	0.0193 (7)	0.0247 (8)	0.0271 (8)	−0.0011 (6)	0.0091 (6)	0.0064 (6)
C5	0.0265 (8)	0.0185 (8)	0.0330 (8)	−0.0014 (6)	0.0133 (6)	0.0005 (6)
C6	0.0168 (6)	0.0192 (7)	0.0173 (7)	0.0011 (5)	0.0040 (6)	−0.0003 (5)
C7	0.0199 (7)	0.0200 (7)	0.0198 (7)	0.0010 (5)	0.0084 (6)	−0.0001 (5)
C8	0.0231 (7)	0.0190 (7)	0.0200 (7)	0.0009 (5)	0.0093 (6)	0.0002 (5)
C9	0.0199 (7)	0.0203 (7)	0.0174 (7)	0.0021 (5)	0.0055 (6)	−0.0002 (5)

Geometric parameters (Å, º)

O1—C6	1.2209 (14)	C4—H4	0.9300
N1—C1	1.3440 (16)	C5—H5	0.9300
N1—C5	1.3448 (16)	C6—C7	1.5010 (17)
N2—C6	1.3717 (16)	C7—C8	1.5108 (17)
N2—C1	1.4000 (16)	C7—H7A	0.9700
N2—H2A	0.8600	C7—H7B	0.9700
C1—C2	1.3914 (18)	C8—C9	1.5185 (18)
C2—C3	1.3783 (17)	C8—H8A	0.9700
C2—H2	0.9300	C8—H8B	0.9700
C3—C4	1.3840 (18)	C9—C9^i	1.515 (2)
C3—H3	0.9300	C9—H9A	0.9700
C4—C5	1.3711 (19)	C9—H9B	0.9700
C1—N1—C5	116.16 (11)	O1—C6—C7	123.17 (11)
C6—N2—C1	128.73 (11)	N2—C6—C7	113.27 (10)
C6—N2—H2A	115.6	C6—C7—C8	115.01 (10)
C1—N2—H2A	115.6	C6—C7—H7A	108.5
N1—C1—C2	123.42 (11)	C8—C7—H7A	108.5
N1—C1—N2	113.04 (11)	C6—C7—H7B	108.5
C2—C1—N2	123.53 (12)	C8—C7—H7B	108.5
C3—C2—C1	118.14 (12)	H7A—C7—H7B	107.5
C3—C2—H2	120.9	C7—C8—C9	112.96 (10)
C1—C2—H2	120.9	C7—C8—H8A	109.0
C2—C3—C4	119.85 (13)	C9—C8—H8A	109.0
C2—C3—H3	120.1	C7—C8—H8B	109.0
C4—C3—H3	120.1	C9—C8—H8B	109.0
C5—C4—C3	117.52 (12)	H8A—C8—H8B	107.8
C5—C4—H4	121.2	C9^i—C9—C8	113.43 (13)
C3—C4—H4	121.2	C9^i—C9—H9A	108.9
N1—C5—C4	124.92 (12)	C8—C9—H9A	108.9
N1—C5—H5	117.5	C9^i—C9—H9B	108.9
C4—C5—H5	117.5	C8—C9—H9B	108.9
O1—C6—N2	123.56 (12)	H9A—C9—H9B	107.7

Symmetry code: (i) −x, −y, −z+2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···N1^ii	0.86	2.45	3.3065 (15)	171
C2—H2···O1	0.93	2.28	2.8716 (15)	121
C4—H4···O1^iii	0.93	2.42	3.1585 (15)	136

Symmetry codes: (ii) −x, −y+1, −z+2; (iii) −x+1/2, y+1/2, −z+3/2.