Role of weak C—H...O and strong N—H...O inter­molecular inter­actions on the high-symmetry mol­ecular packing of trans-cyclo­hexane-1,4-dicarboxamide

An unpredicted fourfold screw N—H...O hydrogen bond C(4) motif in a primary dicarboxamide (trans-cyclo­hexane-1,4-dicarboxamide, C₈H₁₄N₂O₂) was investigated by single-crystal X-ray diffraction and IR and Raman spectroscopies. Electron-density topology and inter­molecular energy analyses determined from ab initio calculations were employed to examine the influence of weak C—H...O hydrogen-bond inter­actions on the peculiar arrangement of mol­ecules in the tetra­gonal P4₃2₁2 space group. In addition, the way in which the co-operative effects of those weak bonds might modify their relative influence on mol­ecular packing was estimated from cluster calculations. Based on the results, a structural model is proposed which helps to rationalize the unusual fourfold screw mol­ecular arrangement.

Computing details

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: PLATON (Spek, 2009) and PARST (Nardelli, 1995) within WinGX (Farrugia, 2012).

trans-Cyclohexane-1,4-dicarboxamide

Crystal data

C8H14N2O2	Dx = 1.236 Mg m^−3
Mr = 170.21	Cu Kα radiation, λ = 1.54184 Å
Tetragonal, P43212	Cell parameters from 854 reflections
Hall symbol: P 4nw 2abw	θ = 4.7–69.5°
a = 6.9584 (2) Å	µ = 0.74 mm^−1
c = 18.8979 (6) Å	T = 293 K
V = 915.02 (6) Å^3	Frag, colourless
Z = 4	0.25 × 0.12 × 0.12 mm
F(000) = 368

Data collection

Agilent Xcalibur Eos Gemini diffractometer	890 independent reflections
Radiation source: Enhance (Cu) X-ray Source	837 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.014
Detector resolution: 16.0604 pixels mm^-1	θmax = 72.0°, θmin = 6.8°
ω scans	h = −8→8
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014)	k = −6→7
Tmin = 0.893, Tmax = 1	l = −11→23
1745 measured reflections

Refinement

Refinement on F^2	Hydrogen site location: difference Fourier map
Least-squares matrix: full	Only H-atom displacement parameters refined
R[F^2 > 2σ(F^2)] = 0.044	w = 1/[σ^2(Fo^2) + (0.075P)^2 + 0.1598P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.130	(Δ/σ)max < 0.001
S = 1.07	Δρmax = 0.23 e Å^−3
890 reflections	Δρmin = −0.13 e Å^−3
68 parameters	Absolute structure: Flack x determined using 278 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
0 restraints	Absolute structure parameter: −0.1 (3)

Special details

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

Refinement. The measurements were performed on a Rigaku Oxford Diffraction EOS CCD diffractometer with graphite-monochromated Cu Kα (λ = 1.54184 Å) radiation. X-ray diffraction intensities were collected (ω scans with θ and κ offsets), integrated and scaled with CrysAlis PRO (Agilent, 2014) suite of programs. The unit-cell parameters were obtained by least-squares refinement (based on the angular settings for all collected reflections with intensities larger than seven times the standard deviation of measurement errors) using CrysAlis PRO. Data were corrected empirically for absorption employing the multi-scan method implemented in CrysAlis PRO. The molecular structure was solved by direct methods with SHELXS and the molecular model refined by full-matrix least-squares procedure with SHELXL, both codes belong to the SHELX suite of programs (2008). After non-hydrogen atoms were anisotropically refined, hydrogen atoms were localized from Fourier difference maps and refined riding on bound atoms. ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006) programs were used for structure analysis and to prepare material for publication. Details of data collection and structure refinement are summarized in Table 1. PLATON (Spek, 2009) and PARST (Nardelli, 1995) programs were used within WinGX (Farrugia, 2012) to prepare tables for publication.

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

	x	y	z	Uiso*/Ueq
O5	0.3771 (3)	1.0600 (3)	0.54566 (9)	0.0602 (6)
N6	0.3328 (4)	1.0717 (4)	0.42891 (11)	0.0549 (7)
H62	0.367 (5)	1.033 (6)	0.3894 (17)	0.067 (10)*
H61	0.245 (6)	1.159 (6)	0.4352 (17)	0.070 (10)*
C4	0.4181 (3)	1.0038 (3)	0.48545 (11)	0.0425 (6)
C1	0.5696 (4)	0.8512 (4)	0.47394 (12)	0.0458 (6)
H11	0.5774	0.8366	0.4274	0.051 (8)*
C3	0.7604 (4)	0.9142 (4)	0.5055 (2)	0.0696 (9)
H31	0.7398	0.9341	0.5572	0.072 (10)*
H32	0.7948	1.0401	0.4778	0.135 (18)*
C2	0.5077 (4)	0.6614 (4)	0.5047 (2)	0.0694 (10)
H21	0.4976	0.6845	0.5572	0.073 (10)*
H22	0.3798	0.6212	0.481	0.084 (12)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O5	0.0700 (13)	0.0727 (13)	0.0379 (8)	0.0316 (10)	−0.0028 (8)	−0.0087 (8)
N6	0.0645 (14)	0.0621 (14)	0.0381 (10)	0.0287 (12)	−0.0010 (9)	−0.0008 (9)
C4	0.0455 (12)	0.0434 (12)	0.0387 (11)	0.0097 (9)	−0.0002 (9)	−0.0026 (9)
C1	0.0520 (14)	0.0484 (13)	0.0371 (10)	0.0170 (11)	0.0020 (10)	−0.0034 (9)
C3	0.0443 (14)	0.0422 (14)	0.122 (3)	0.0028 (12)	0.0018 (17)	−0.0071 (16)
C2	0.0384 (13)	0.0478 (16)	0.122 (3)	0.0028 (12)	0.0023 (17)	−0.0006 (17)

Geometric parameters (Å, º)

O5—C4	1.237 (3)	C1—H11	0.8876
N6—C4	1.311 (3)	C3—C3^i	1.528 (6)
N6—H62	0.83 (3)	C3—H31	0.9969
N6—H61	0.87 (4)	C3—H32	1.0476
C4—C1	1.511 (3)	C2—C2^i	1.523 (5)
C1—C2	1.506 (4)	C2—H21	1.0078
C1—C3	1.520 (4)	C2—H22	1.0349
C4—N6—H62	119 (2)	C1—C3—C3^i	110.9 (2)
C4—N6—H61	117 (2)	C1—C3—H31	107.4
H62—N6—H61	123 (3)	C3^i—C3—H31	109.3
O5—C4—N6	122.1 (2)	C1—C3—H32	104.2
O5—C4—C1	121.1 (2)	C3^i—C3—H32	111
N6—C4—C1	116.9 (2)	H31—C3—H32	113.9
C2—C1—C4	111.2 (2)	C1—C2—C2^i	111.7 (2)
C2—C1—C3	110.6 (2)	C1—C2—H21	105.1
C4—C1—C3	110.5 (2)	C2^i—C2—H21	106
C2—C1—H11	107.5	C1—C2—H22	108.4
C4—C1—H11	105.4	C2^i—C2—H22	111.3
C3—C1—H11	111.6	H21—C2—H22	114.2
O5—C4—C1—C2	65.6 (4)	C2—C1—C3—C3^i	56.2 (4)
N6—C4—C1—C2	−114.0 (3)	C4—C1—C3—C3^i	179.6 (3)
O5—C4—C1—C3	−57.5 (4)	C4—C1—C2—C2^i	−178.4 (3)
N6—C4—C1—C3	122.8 (3)	C3—C1—C2—C2^i	−55.3 (4)

Symmetry code: (i) y, x, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N6—H62···O5^ii	0.83 (3)	2.14 (4)	2.955 (3)	169 (4)
N6—H61···O5^iii	0.87 (4)	2.02 (4)	2.889 (3)	175 (4)
N6—H62···O5^ii	0.83 (3)	2.14 (4)	2.955 (3)	169 (4)
N6—H61···O5^iii	0.87 (4)	2.02 (4)	2.889 (3)	175 (4)
C1—H11···O5^ii	0.89	2.68	3.492 (3)	152.5
C2—H22···O5^iv	1.03	2.84	3.811 (4)	155.6
C3—H32···O5^v	1.05	3.02	3.956 (4)	149.7

Symmetry codes: (ii) −y+3/2, x+1/2, z−1/4; (iii) y−1, x+1, −z+1; (iv) y−1, x, −z+1; (v) y, x+1, −z+1.

Topological analysis of selected contacts calculated at PBE/6-31G** theory level for clusters I and II^a

Contact	Comp	ρ	\nabla^2 (e A^-3)	λ3 (e A^-3)	G (kcal mol^-1)	V (kcal mol^-1)	H (kcal mol^-1)
N—Hs···O	1	0.2247	2.2884	4.5124	15.5	-16.1	-0.6
	2	0.2314	2.4308	4.7490	16.3	-16.7	-0.4
N—Ha···O	1	0.1566	1.7486	3.1217	11.6	-11.9	-0.3
	2	0.1718	1.8356	3.3832	12.4	-12.9	-0.5
C—Hin···O	1	0.0469	0.5597	0.8408	3.2	-2.8	0.4
	2	0.0803	0.8597	1.4336	5.6	-5.5	0.1
C—Hout···O	1	0.0453	0.5792	0.8289	3.3	-2.7	0.6
	2	0.0455	0.5647	0.8433	3.2	-2.7	0.5

(a) ρ(r) electron density, its Laplacian, \nable²ρ(r), positive principal curvature, λ₃, G(r) kinetic, V(r) potential and H(r) total energy densities evaluated at the corresponding (3,-1) critical points.