N,N′-Dicyclo­hexyl­ethyl­enediammonium dichloride

In the title compound, C₁₄H₃₀N₂²⁺·2Cl⁻, the N,N′-dicyclo­hexyl­ethyl­enediammonium cation posseses crystallographic symmetry, and thus the compound crystallizes with two formula units per unit cell. In the crystal, the cations and anions are linked by N—H...Cl hydrogen bonds, giving a two-dimensional network with {6,3} topology.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.035
• wR factor = 0.089
• Data-to-parameter ratio = 11.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT042_ALERT_1_C Calc. and Reported MoietyFormula Strings  Differ          ?
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600          2

Alert level G
PLAT063_ALERT_4_G Crystal Size Likely too Large for Beam Size ....       0.65 mm
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K

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

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

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S1. Comment

Compared to other N,N'-disubstituted ethylenediamine compounds RNH-CH₂CH₂—NHR (R = Me, Ph, etc.) N,N'-Dicyclohexylethylenediamine derivatives have been studied only rarely by X-ray diffraction. One of the few examples is the Iridium complex [Cp*(CyNHCH₂CH₂NHCy)HIr][H₃BCN] (Greulich et al., 2002).

The crystal structure of the title compound (Fig. 1) consists of [CyNH₂CH₂CH₂NH₂Cy]²⁺ cations and Cl^- anions. The [CyNH₂CH₂CH₂NH₂Cy]²⁺ cations exhibit crystallographic 1 symmetry and thus an exactly staggered conformation with a N—C—C—N torsion angle of 180 ° is observed. The N atoms display a distorted tetrahedral coordination with H—N—C angles of 108.6 to 111.2 and a C—N—C angle of 114.50 (1)°. The cyclohexyl groups adopt a chair conformation (Fig. 2) as it was observed in [Cp*(CyNHCH₂CH₂NHCy)HIr][H₃BCN] (Greulich et al., 2002). Both hydrogen atoms of the NH₂ groups are involved in hydrogen bridges to neighbouring Cl^- anions. The NH···Cl distances of 2.20 (2) and 2.30 (2) Å are comparable to those found in other cyclohexylammonium derivatives like [CyNH₃]Cl (2.187–2.35.4 Å) (Smith et al., 1994) and [CyNH₃]₂(AlCl₄)Cl (2.305–2.478 Å) (Martell & Zaworotko, 1991) respectively. The N—H···Cl angles of 169 (2)° and 176 (2)° are in the expected range for hydrogen bridges of moderate strength (Steiner, 2002).

On balance each [CyNH₂CH₂CH₂NH₂Cy]²⁺ cation forms four N—H···Cl bridges to neighbouring Cl^- anions and each Cl^- anion acts as H-acceptor for two NH hydrogen atoms. As a result of the hydrogen bonding between [CyNH₂CH₂CH₂NH₂Cy]²⁺ cations and Cl^- anions a two-dimensional layer structure is formed. The layers consist of puckered C₄H₈N₆Cl₄ rings that are interconnected to give a honeycomb arrangement with {6,3} net topology (Wells & Sharpe, 1963).

Related literature

For the crystal structures of cyclohexylammonium derivatives, see Smith et al. (1994); Martell & Zaworotko (1991). For the crystal structure of an iridium complex with the N,N'-dicyclohexylethylenediamine ligand, see: Greulich et al. (2002). For a review of hydrogen bonding, see Steiner (2002). N,N'-dicyclohexylethylenediamine was prepared according to Denk et al. (2003). For the topology of {6,3} ring systems and three-dimensional polyhedra and networks, see: Wells & Sharpe (1963).

S2. Experimental

An excess of hydrochloric acid was added dropwise to a solution of N,N'-Dicyclohexylethylenediamine monohydrate (1.11 g, 5 mmol) prepared by standard techniques (Denk et al., 2003) in a ethanol/water mixture(10:1, 20 ml) and stirred for 6 h at 140 °C in an autoclave. The mixture was slowly cooled to ambient temperature and colourless plate-like crystals were obtained. Spectroscopic data: ¹H NMR (D₂O, 500 MHz, 298 K, p.p.m.): δ 1.07–1.99 (m, 20 H, CH_2, Cy), 3.09 (m, 2H, CH), 3.32 (s, 4H, CH₂); ¹³C NMR (D₂O, 125 MHz, 298 K, p.p.m.): δ 23.7 (s, CH₂, Cy: C4, C6), 24.3 (s, CH₂, Cy: C5), 26.7 (s, CH₂, Cy: C3, C7), 40.0 (s, CH₂), 57.934 (s, CH, Cy).

Computing details

Data collection: STADI4 (Stoe & Cie, 1996); cell refinement: STADI4 (Stoe & Cie, 1996); data reduction: X-RED (Stoe & Cie, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. Molecular structure of the [CyNH2CH2CH2NH2Cy]^2+ cation with surrounding Cl^- anions. The asymmetric unit is shown by filled bonds. Thermal ellipsoids are drawn at the 50% probability level. Symmetry codes: (i) -x, -y, -z; (ii) -x, -1/2 + y, 1.5 - z; (iii) x, 1.5 - y, -1/2 + z
	Fig. 2. Part of the layer structure formed by hydrogen bonded [CyNH2CH2CH2NH2Cy]^2+ cations and Cl^- anions. Cyclohexyl groups are omitted for clarity.

N,N'-Dicyclohexylethylenediammonium dichloride

Crystal data

C14H30N2^2+·2Cl^−	F(000) = 324
Mr = 297.30	Dx = 1.163 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 22 reflections
a = 11.551 (3) Å	θ = 10.2–14.6°
b = 6.785 (2) Å	µ = 0.37 mm^−1
c = 10.8434 (17) Å	T = 293 K
β = 91.892 (15)°	Plate, colourless
V = 849.3 (4) Å^3	0.65 × 0.28 × 0.12 mm
Z = 2

Data collection

Stoe STADI4 diffractometer	Rint = 0.036
Radiation source: fine-focus sealed tube	θmax = 26.1°, θmin = 1.8°
Graphite monochromator	h = −14→14
2θ/ω scans	k = −8→0
3349 measured reflections	l = −13→13
1675 independent reflections	2 standard reflections every 120 min
1430 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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.089	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ^2(Fo^2) + (0.0304P)^2 + 0.223P] where P = (Fo^2 + 2Fc^2)/3
1675 reflections	(Δ/σ)max < 0.001
142 parameters	Δρmax = 0.23 e Å^−3
0 restraints	Δρmin = −0.28 e Å^−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. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	Uiso*/Ueq
C1	0.05608 (15)	0.4477 (3)	0.48641 (16)	0.0404 (4)
H2	0.1138 (18)	0.537 (3)	0.4631 (19)	0.054 (6)*
H1	0.0449 (18)	0.353 (3)	0.419 (2)	0.059 (6)*
C2	0.21086 (13)	0.2307 (2)	0.58171 (14)	0.0342 (3)
H5	0.2039 (14)	0.163 (3)	0.5053 (16)	0.038 (4)*
C3	0.22533 (16)	0.0777 (3)	0.6834 (2)	0.0478 (5)
H6	0.2248 (18)	0.147 (3)	0.763 (2)	0.059 (6)*
H7	0.1619 (18)	−0.009 (4)	0.6755 (18)	0.058 (6)*
C4	0.33978 (18)	−0.0313 (3)	0.6726 (3)	0.0574 (5)
H8	0.3397 (19)	−0.095 (3)	0.596 (2)	0.063 (7)*
H9	0.346 (2)	−0.123 (4)	0.738 (2)	0.069 (7)*
C5	0.44122 (17)	0.1104 (3)	0.6751 (2)	0.0513 (5)
H10	0.4456 (18)	0.173 (3)	0.757 (2)	0.064 (6)*
H11	0.516 (2)	0.045 (3)	0.668 (2)	0.068 (6)*
C6	0.42621 (16)	0.2660 (3)	0.5755 (2)	0.0522 (5)
H12	0.4254 (18)	0.198 (3)	0.497 (2)	0.064 (6)*
H13	0.492 (2)	0.354 (4)	0.581 (2)	0.075 (7)*
C7	0.31115 (15)	0.3757 (3)	0.58388 (18)	0.0419 (4)
H14	0.3073 (17)	0.447 (3)	0.6637 (19)	0.054 (6)*
H15	0.3005 (17)	0.466 (3)	0.5188 (18)	0.053 (6)*
N	0.09763 (12)	0.3358 (2)	0.59677 (13)	0.0335 (3)
H4	0.1015 (17)	0.416 (3)	0.6647 (19)	0.052 (6)*
H3	0.0454 (17)	0.257 (3)	0.6169 (17)	0.045 (5)*
Cl	0.12073 (4)	0.59342 (7)	0.83342 (4)	0.04938 (17)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0421 (9)	0.0418 (9)	0.0375 (8)	0.0074 (8)	0.0039 (7)	0.0097 (7)
C2	0.0376 (8)	0.0297 (8)	0.0351 (8)	0.0025 (6)	−0.0004 (6)	−0.0027 (6)
C3	0.0413 (10)	0.0349 (9)	0.0670 (13)	−0.0006 (8)	−0.0007 (8)	0.0165 (9)
C4	0.0521 (11)	0.0354 (9)	0.0838 (16)	0.0089 (9)	−0.0074 (10)	0.0073 (11)
C5	0.0405 (10)	0.0492 (11)	0.0638 (12)	0.0098 (8)	−0.0038 (8)	0.0007 (9)
C6	0.0391 (9)	0.0583 (12)	0.0596 (12)	0.0033 (9)	0.0088 (8)	0.0046 (10)
C7	0.0383 (9)	0.0361 (9)	0.0514 (10)	−0.0011 (7)	0.0039 (7)	0.0081 (8)
N	0.0338 (7)	0.0314 (7)	0.0352 (7)	−0.0018 (6)	0.0011 (5)	0.0043 (6)
Cl	0.0569 (3)	0.0446 (3)	0.0467 (3)	0.0160 (2)	0.00215 (19)	−0.00631 (19)

Geometric parameters (Å, º)

C1—N	1.484 (2)	C4—H8	0.94 (2)
C1—C1^i	1.514 (3)	C4—H9	0.95 (2)
C1—H2	0.94 (2)	C5—C6	1.516 (3)
C1—H1	0.98 (2)	C5—H10	0.98 (2)
C2—N	1.503 (2)	C5—H11	0.98 (2)
C2—C7	1.519 (2)	C6—C7	1.529 (2)
C2—C3	1.519 (2)	C6—H12	0.97 (2)
C2—H5	0.948 (18)	C6—H13	0.97 (3)
C3—C4	1.523 (3)	C7—H14	0.99 (2)
C3—H6	0.98 (2)	C7—H15	0.94 (2)
C3—H7	0.94 (2)	N—H4	0.91 (2)
C4—C5	1.515 (3)	N—H3	0.84 (2)
N—C1—C1^i	109.80 (17)	C4—C5—C6	111.01 (17)
N—C1—H2	109.4 (13)	C4—C5—H10	108.0 (13)
C1^i—C1—H2	111.7 (12)	C6—C5—H10	109.9 (13)
N—C1—H1	107.3 (13)	C4—C5—H11	113.4 (14)
C1^i—C1—H1	111.1 (12)	C6—C5—H11	109.8 (13)
H2—C1—H1	107.4 (17)	H10—C5—H11	104.5 (18)
N—C2—C7	110.89 (13)	C5—C6—C7	112.07 (16)
N—C2—C3	108.69 (13)	C5—C6—H12	107.2 (13)
C7—C2—C3	111.44 (15)	C7—C6—H12	107.4 (13)
N—C2—H5	106.0 (10)	C5—C6—H13	108.4 (14)
C7—C2—H5	111.7 (10)	C7—C6—H13	112.4 (14)
C3—C2—H5	107.9 (11)	H12—C6—H13	109.2 (18)
C2—C3—C4	110.54 (17)	C2—C7—C6	110.34 (15)
C2—C3—H6	108.0 (12)	C2—C7—H14	105.8 (12)
C4—C3—H6	109.2 (12)	C6—C7—H14	110.7 (12)
C2—C3—H7	107.1 (13)	C2—C7—H15	109.3 (12)
C4—C3—H7	111.5 (13)	C6—C7—H15	111.5 (12)
H6—C3—H7	110.5 (17)	H14—C7—H15	109.1 (17)
C5—C4—C3	111.30 (17)	C1—N—C2	114.50 (13)
C5—C4—H8	106.8 (14)	C1—N—H4	110.6 (12)
C3—C4—H8	108.5 (14)	C2—N—H4	110.5 (13)
C5—C4—H9	111.3 (14)	C1—N—H3	108.6 (13)
C3—C4—H9	107.9 (14)	C2—N—H3	111.1 (13)
H8—C4—H9	111 (2)	H4—N—H3	100.6 (17)
N—C2—C3—C4	−179.40 (16)	C3—C2—C7—C6	55.7 (2)
C7—C2—C3—C4	−56.9 (2)	C5—C6—C7—C2	−54.8 (2)
C2—C3—C4—C5	56.5 (3)	C1^i—C1—N—C2	−178.21 (18)
C3—C4—C5—C6	−55.5 (3)	C7—C2—N—C1	73.57 (19)
C4—C5—C6—C7	54.9 (2)	C3—C2—N—C1	−163.61 (15)
N—C2—C7—C6	176.95 (14)

Symmetry code: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N—H4···Cl	0.91 (2)	2.20 (2)	3.1088 (16)	175.8 (18)
N—H3···Cl^ii	0.84 (2)	2.30 (2)	3.1250 (16)	168.8 (18)

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