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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 11| November 2011| Page o3007
doi:10.1107/S1600536811042917

Heptane-1,7-diaminium dinitrate

Charmaine Ardernea*

aUniversity of Johannesburg, Department of Chemistry, PO Box 524, Auckland Park, Johannesburg 2006, South Africa
*Correspondence e-mail: carderne@uj.ac.za

(Received 20 September 2011; accepted 17 October 2011; online 22 October 2011)

In the title molecular salt, C7H20N22+·2NO3−, the crystal structure exhibits an unusual back-to-back paired double-stacked packing arrangement culminating in an overall double zigzag pattern of the dications. The nitrate anions form a ring around one pair of double-stacked dications. An intricate three-dimensional N—H⋯O and N—H⋯(O,O) hydrogen-bonding network exists in the crystal structure.

Related literature

For related structural studies of n-alkyl-diammonium nitrate salts, see: van Blerk & Kruger (2009[Blerk, C. van & Kruger, G. J. (2009). Acta Cryst. E65, o1008.]). For the Cambridge Structural Database, see: Allen (2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]).

[Scheme 1]

Experimental

Crystal data

  • C7H20N22+·2NO3−

  • Mr = 256.27

  • Monoclinic, P 21 /n

  • a = 5.3236 (1) Å

  • b = 16.8340 (4) Å

  • c = 14.9845 (3) Å

  • β = 96.500 (1)°

  • V = 1334.24 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 295 K

  • 0.44 × 0.35 × 0.32 mm
Data collection

  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (AX-SCALE; Bruker, 2008[Bruker (2008). AX-SCALE and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.953, Tmax = 0.966

  • 16750 measured reflections

  • 2343 independent reflections

  • 1828 reflections with I > 2σ(I)

  • Rint = 0.032
Refinement

  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.124

  • S = 1.06

  • 2343 reflections

  • 157 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1C⋯O4i 0.89 2.16 2.956 (2) 149
N1—H1C⋯O6ii 0.89 2.62 3.129 (2) 118
N1—H1D⋯O1ii 0.89 2.09 2.951 (2) 161
N1—H1D⋯O3ii 0.89 2.40 3.035 (2) 129
N1—H1E⋯O1i 0.89 2.04 2.871 (2) 155
N1—H1E⋯O2i 0.89 2.43 3.208 (3) 147
N2—H2C⋯O2iii 0.89 2.26 3.142 (2) 172
N2—H2C⋯O3iii 0.89 2.26 2.911 (2) 130
N2—H2D⋯O4iv 0.89 2.07 2.901 (2) 155
N2—H2E⋯O4v 0.89 2.44 3.0064 (19) 122
N2—H2E⋯O6v 0.89 2.08 2.967 (2) 171
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (ii) [x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (iii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iv) -x+1, -y+1, -z+2; (v) x+1, y, z.

Data collection: SMART-NT (Bruker, 1999[Bruker (1999). SMART-NT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). AX-SCALE and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811042917/ez2262sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811042917/ez2262Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811042917/ez2262Isup3.mol

Supporting information file. DOI: 10.1107/S1600536811042917/ez2262Isup4.cml

checkCIF report


Comment top

The crystal structure of the title compound (I) adds to our current ongoing investigations of long-chained diammonium inorganic mineral acid salts (van Blerk & Kruger, 2009). Colourless crystals of heptane-1,7-diammonium dinitrate were obtained and analyzed by single-crystal X-ray diffraction techniques. This material forms part of our structural chemistry study of the inorganic mineral acid salts of the n-alkyldiamines. A search of the Cambridge Structural Database (Version 5.32, Allen, 2002) revealed that this compound had not previously been determined.

The asymmetric unit of compound (I) contains one diammonium dication and two nitrate anions with all atoms occupying general positions. The hydrocarbon chain is also fully extended with very slight deviations from planarity chain as is evident from the torsion angles along the hydrocarbon chain (tabulated in Table 1). The molecular structure of (I) is shown in Fig. 1.

Fig. 2 illustrates the packing arrangement of the title compound (I) viewed down the a axis. The diammonium cations pack back-to-back, in pairs in a double zig-zag pattern. Each dication pair is completely surrounded by a ring of nitrate anions. An extensive three-dimensional hydrogen-bonding network is also formed of N—H···O hydrogen bonds.

A close-up view of selected hydrogen bonding interactions can be viewed in Fig. 3. The three-dimensional hydrogen bonding network is built and linked through hydrogen bonding interactions between the ammonium groups of the dication and the nitrate anions. Clear evidence of bifurcated hydrogen bonding interactions can also be seen in this illustration. The hydrogen bond distances and angles for the title compound (I) can be found in Table 2.

Related literature top

For related structural studies of n-alkyl-diammonium nitrate salts, see: van Blerk & Kruger (2009). For the Cambridge Structural Database, see: Allen (2002).

Experimental top

Compound (I) was prepared by adding heptane-1,7-diamine (0.50 g, 3.84 mmol) to 55% nitric acid (2 ml, 42.5 mmol, Merck) in a sample vial. The mixture was then refluxed at 363 K for 2 h. The solution was cooled at 2 K h-1 to room temperature. Colourless crystals of heptane-1,7-diammonium dinitrate were collected and a suitable single-crystal was selected for the X-ray diffraction study.

Refinement top

H atoms were geometrically positioned and refined in the riding-model approximation, with C—H = 0.97 Å, N—H = 0.89 Å, and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(N). For (I), the highest peak in the final difference map is 1.05 Å from O3 and the deepest hole is 0.87 Å from O3.

Computing details top

Data collection: SMART-NT (Bruker, 1999); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, with atomic numbering scheme and displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing arrangement of the title compound viewed down the a axis. Selected hydrogen bonds are indicated by red dashed lines.
[Figure 3] Fig. 3. Close-up view of the title compound clearly showing selected hydrogen-bonding interactions. Hydrogen bonds are indicated by green dashed lines.
Heptane-1,7-diaminium dinitrate top
Crystal data top
C7H20N22+·2NO3−F(000) = 552
Mr = 256.27Dx = 1.276 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 8072 reflections
a = 5.3236 (1) Åθ = 2.4–24.5°
b = 16.8340 (4) ŵ = 0.11 mm−1
c = 14.9845 (3) ÅT = 295 K
β = 96.500 (1)°Block, colourless
V = 1334.24 (5) Å30.44 × 0.35 × 0.32 mm
Z = 4
Data collection top
Bruker SMART CCD
diffractometer		2343 independent reflections
Radiation source: fine-focus sealed tube1828 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
ϕ and ω scansθmax = 25.0°, θmin = 1.8°
Absorption correction: multi-scan
(AX-SCALE; Bruker, 2008)		h = −6→6
Tmin = 0.953, Tmax = 0.966k = −19→19
16750 measured reflectionsl = −17→17
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.042H-atom parameters constrained
wR(F2) = 0.124 w = 1/[σ2(Fo2) + (0.0558P)2 + 0.3767P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
2343 reflectionsΔρmax = 0.29 e Å−3
157 parametersΔρmin = −0.18 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.027 (3)
Crystal data top
C7H20N22+·2NO3−V = 1334.24 (5) Å3
Mr = 256.27Z = 4
Monoclinic, P21/nMo Kα radiation
a = 5.3236 (1) ŵ = 0.11 mm−1
b = 16.8340 (4) ÅT = 295 K
c = 14.9845 (3) Å0.44 × 0.35 × 0.32 mm
β = 96.500 (1)°
Data collection top
Bruker SMART CCD
diffractometer		2343 independent reflections
Absorption correction: multi-scan
(AX-SCALE; Bruker, 2008)		1828 reflections with I > 2σ(I)
Tmin = 0.953, Tmax = 0.966Rint = 0.032
16750 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.124H-atom parameters constrained
S = 1.06Δρmax = 0.29 e Å−3
2343 reflectionsΔρmin = −0.18 e Å−3
157 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
C10.2521 (4)0.71038 (12)0.43729 (16)0.0700 (6)
H1A0.19000.66620.39940.084*
H1B0.12820.72130.47840.084*
C20.4951 (4)0.68708 (14)0.48992 (15)0.0703 (6)
H2A0.56710.73310.52230.084*
H2B0.61270.67030.44870.084*
C30.4660 (4)0.62061 (13)0.55650 (14)0.0683 (6)
H3A0.35150.63800.59860.082*
H3B0.38990.57510.52430.082*
C40.7127 (4)0.59522 (14)0.60854 (15)0.0724 (6)
H4A0.81820.57100.56730.087*
H4B0.80000.64200.63390.087*
C50.6812 (4)0.53735 (13)0.68327 (14)0.0670 (5)
H5A0.59060.49110.65800.080*
H5B0.57810.56200.72490.080*
C60.9287 (4)0.50997 (13)0.73523 (13)0.0617 (5)
H6A1.02230.47830.69620.074*
H6B1.03060.55600.75430.074*
C70.8826 (3)0.46172 (11)0.81595 (13)0.0571 (5)
H7A0.78540.49310.85410.068*
H7B0.78310.41530.79650.068*
N10.2774 (3)0.78115 (9)0.38028 (11)0.0612 (4)
H1C0.31760.82320.41500.092*
H1D0.13150.79010.34660.092*
H1E0.39830.77270.34490.092*
N21.1202 (3)0.43572 (9)0.86872 (10)0.0563 (4)
H2C1.19560.39940.83780.084*
H2D1.08550.41480.92050.084*
H2E1.22240.47730.87960.084*
N30.2584 (3)0.77064 (11)0.75577 (11)0.0643 (5)
N40.3365 (3)0.60428 (9)0.97456 (10)0.0524 (4)
O10.2441 (3)0.70920 (9)0.80187 (11)0.0828 (5)
O20.0960 (4)0.82199 (13)0.75256 (13)0.1094 (7)
O30.4470 (3)0.78063 (11)0.71661 (13)0.0983 (6)
O40.1024 (2)0.59148 (8)0.96594 (8)0.0579 (4)
O50.4312 (3)0.65102 (10)1.03157 (11)0.0859 (5)
O60.4699 (3)0.56836 (8)0.92489 (11)0.0731 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0538 (11)0.0625 (12)0.0923 (15)−0.0014 (9)0.0016 (10)0.0079 (11)
C20.0556 (11)0.0777 (14)0.0755 (13)−0.0033 (10)−0.0012 (10)0.0081 (11)
C30.0584 (12)0.0721 (13)0.0727 (13)−0.0007 (10)−0.0003 (10)0.0041 (11)
C40.0593 (12)0.0834 (15)0.0729 (13)−0.0023 (11)0.0004 (10)0.0120 (11)
C50.0561 (11)0.0755 (13)0.0683 (12)−0.0021 (10)0.0020 (9)0.0050 (10)
C60.0528 (11)0.0696 (12)0.0624 (11)−0.0009 (9)0.0045 (9)0.0033 (10)
C70.0504 (10)0.0580 (11)0.0631 (11)0.0000 (8)0.0078 (8)−0.0033 (9)
N10.0513 (9)0.0562 (9)0.0743 (11)0.0003 (7)0.0001 (8)−0.0044 (8)
N20.0582 (9)0.0552 (9)0.0548 (9)0.0062 (7)0.0033 (7)−0.0041 (7)
N30.0607 (10)0.0703 (11)0.0601 (10)−0.0032 (9)−0.0014 (8)0.0114 (8)
N40.0455 (9)0.0497 (9)0.0609 (9)0.0030 (7)0.0016 (7)0.0092 (7)
O10.0805 (11)0.0728 (10)0.0962 (11)−0.0081 (8)0.0145 (8)0.0310 (9)
O20.0942 (13)0.1239 (15)0.1122 (14)0.0452 (12)0.0216 (11)0.0440 (12)
O30.0797 (11)0.1003 (13)0.1192 (14)−0.0011 (9)0.0293 (10)0.0406 (11)
O40.0425 (7)0.0639 (8)0.0674 (8)0.0010 (6)0.0061 (6)0.0046 (6)
O50.0768 (11)0.0803 (11)0.0948 (11)−0.0076 (8)−0.0155 (9)−0.0181 (9)
O60.0574 (8)0.0696 (9)0.0967 (11)0.0094 (7)0.0286 (8)0.0016 (8)
Geometric parameters (Å, º) top
C1—N11.481 (3)C6—H6A0.9700
C1—C21.489 (3)C6—H6B0.9700
C1—H1A0.9700C7—N21.480 (2)
C1—H1B0.9700C7—H7A0.9700
C2—C31.519 (3)C7—H7B0.9700
C2—H2A0.9700N1—H1C0.8900
C2—H2B0.9700N1—H1D0.8900
C3—C41.511 (3)N1—H1E0.8900
C3—H3A0.9700N2—H2C0.8900
C3—H3B0.9700N2—H2D0.8900
C4—C51.508 (3)N2—H2E0.8900
C4—H4A0.9700N3—O21.220 (2)
C4—H4B0.9700N3—O31.230 (2)
C5—C61.524 (3)N3—O11.251 (2)
C5—H5A0.9700N4—O51.227 (2)
C5—H5B0.9700N4—O61.2424 (19)
C6—C71.500 (3)N4—O41.2570 (18)
N1—C1—C2112.78 (17)C7—C6—C5111.39 (16)
N1—C1—H1A109.0C7—C6—H6A109.4
C2—C1—H1A109.0C5—C6—H6A109.4
N1—C1—H1B109.0C7—C6—H6B109.4
C2—C1—H1B109.0C5—C6—H6B109.4
H1A—C1—H1B107.8H6A—C6—H6B108.0
C1—C2—C3113.25 (18)N2—C7—C6112.51 (15)
C1—C2—H2A108.9N2—C7—H7A109.1
C3—C2—H2A108.9C6—C7—H7A109.1
C1—C2—H2B108.9N2—C7—H7B109.1
C3—C2—H2B108.9C6—C7—H7B109.1
H2A—C2—H2B107.7H7A—C7—H7B107.8
C4—C3—C2113.58 (17)C1—N1—H1C109.5
C4—C3—H3A108.9C1—N1—H1D109.5
C2—C3—H3A108.9H1C—N1—H1D109.5
C4—C3—H3B108.9C1—N1—H1E109.5
C2—C3—H3B108.9H1C—N1—H1E109.5
H3A—C3—H3B107.7H1D—N1—H1E109.5
C5—C4—C3113.76 (17)C7—N2—H2C109.5
C5—C4—H4A108.8C7—N2—H2D109.5
C3—C4—H4A108.8H2C—N2—H2D109.5
C5—C4—H4B108.8C7—N2—H2E109.5
C3—C4—H4B108.8H2C—N2—H2E109.5
H4A—C4—H4B107.7H2D—N2—H2E109.5
C4—C5—C6114.37 (17)O2—N3—O3119.83 (18)
C4—C5—H5A108.7O2—N3—O1121.37 (19)
C6—C5—H5A108.7O3—N3—O1118.72 (18)
C4—C5—H5B108.7O5—N4—O6120.76 (16)
C6—C5—H5B108.7O5—N4—O4120.40 (16)
H5A—C5—H5B107.6O6—N4—O4118.84 (16)
N1—C1—C2—C3173.40 (19)C3—C4—C5—C6178.89 (19)
C1—C2—C3—C4178.6 (2)C4—C5—C6—C7172.16 (18)
C2—C3—C4—C5172.1 (2)C5—C6—C7—N2−178.84 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1C···O4i0.892.162.956 (2)149
N1—H1C···O6ii0.892.623.129 (2)118
N1—H1D···O1ii0.892.092.951 (2)161
N1—H1D···O3ii0.892.403.035 (2)129
N1—H1E···O1i0.892.042.871 (2)155
N1—H1E···O2i0.892.433.208 (3)147
N2—H2C···O2iii0.892.263.142 (2)172
N2—H2C···O3iii0.892.262.911 (2)130
N2—H2D···O4iv0.892.072.901 (2)155
N2—H2E···O4v0.892.443.0064 (19)122
N2—H2E···O6v0.892.082.967 (2)171
Symmetry codes: (i) x+1/2, −y+3/2, z−1/2; (ii) x−1/2, −y+3/2, z−1/2; (iii) −x+3/2, y−1/2, −z+3/2; (iv) −x+1, −y+1, −z+2; (v) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC7H20N22+·2NO3−
Mr256.27
Crystal system, space groupMonoclinic, P21/n
Temperature (K)295
a, b, c (Å)5.3236 (1), 16.8340 (4), 14.9845 (3)
β (°) 96.500 (1)
V (Å3)1334.24 (5)
Z4
Radiation typeMo Kα
µ (mm−1)0.11
Crystal size (mm)0.44 × 0.35 × 0.32
Data collection
DiffractometerBruker SMART CCD
diffractometer
Absorption correctionMulti-scan
(AX-SCALE; Bruker, 2008)
Tmin, Tmax0.953, 0.966
No. of measured, independent and
observed [I > 2σ(I)] reflections		16750, 2343, 1828
Rint0.032
(sin θ/λ)max (Å−1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.124, 1.06
No. of reflections2343
No. of parameters157
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.29, −0.18

Computer programs: SMART-NT (Bruker, 1999), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2008), publCIF (Westrip, 2010) and PLATON (Spek, 2009).

Selected torsion angles (º) top
N1—C1—C2—C3173.40 (19)C3—C4—C5—C6178.89 (19)
C1—C2—C3—C4178.6 (2)C4—C5—C6—C7172.16 (18)
C2—C3—C4—C5172.1 (2)C5—C6—C7—N2−178.84 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1C···O4i0.892.162.956 (2)149
N1—H1C···O6ii0.892.623.129 (2)118
N1—H1D···O1ii0.892.092.951 (2)161
N1—H1D···O3ii0.892.403.035 (2)129
N1—H1E···O1i0.892.042.871 (2)155
N1—H1E···O2i0.892.433.208 (3)147
N2—H2C···O2iii0.892.263.142 (2)172
N2—H2C···O3iii0.892.262.911 (2)130
N2—H2D···O4iv0.892.072.901 (2)155
N2—H2E···O4v0.892.443.0064 (19)122
N2—H2E···O6v0.892.082.967 (2)171
Symmetry codes: (i) x+1/2, −y+3/2, z−1/2; (ii) x−1/2, −y+3/2, z−1/2; (iii) −x+3/2, y−1/2, −z+3/2; (iv) −x+1, −y+1, −z+2; (v) x+1, y, z.
 

Acknowledgements

The author acknowledges the National Research Foundation Thuthuka Programme (grant No. GUN 66314) and the University of Johannesburg for funding for this study. The University of the Witwatersrand is thanked for the use of their facilities and the use of the diffractometer in the Jan Boeyens Structural Chemistry Laboratory.

References

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ISSN: 2056-9890
Volume 67| Part 11| November 2011| Page o3007
doi:10.1107/S1600536811042917
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