1,4-Diazo­niabicyclo­[2.2.2]octane dinitrate

The title compound, C₆H₁₄N₂²⁺·2NO₃^-, was synthesized under hydro­thermal conditions. The asymmetric unit consists of one protonated 1,4-diaza­bicyclo­[2.2.2]octane (DABCO) mol­ecule and two nitrate anions. The structure is stabilized by hydrogen bonding of the nitrate O atoms to the protonated DABCO N atoms, with donor-acceptor distances ranging from 2.729 (2) to 3.111 (2) Å.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.052
• wR factor = 0.156
• Data-to-parameter ratio = 18.9

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT432_ALERT_2_B Short Inter X...Y Contact  O4     ..  C5      ..       2.88 Ang.

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N1
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N4
PLAT432_ALERT_2_C Short Inter X...Y Contact  O5     ..  C4      ..       3.00 Ang.

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          2

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   4 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
   4 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
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

As the field of inorganic organic coordination polymers and metal organic frameworks has developed, it has become increasingly important to explore the oxidation or reduction of organic molecules utlilized in the syntheses of such materials. Consequently the title compound was synthesized as part of an investigation to understand the stability of DABCO under hydrothermal conditions, in the presence of nitrate groups.

S2. Experimental

1,4-Diazabicyclo[2.2.2]octane and concentrated nitric acid were obtained from Sigma-Aldrich. All reagents were used without further purification. 1,4-diazabicyclo[2.2.2]octane (0.098 g, 0.87 mmol) and distilled water (5 g, 278 mmol) were placed into a 23 ml Teflon-lined Parr bomb in the molar ratios of 1.0:320 respectively. The pH was adjusted to 1.5 using concentrated HNO₃. The reaction vessel was then sealed and heated statically at 120 °C for 10 days. Upon cooling to room temperature, a clear colorless solution was obtained. The solvent was allowed to evaporate at room temperature resulting in colourless crystals of the title compound.

S3. Refinement

All H atoms of the DABCO carbons were placed in calculated positions whereas those of the DABCO nitrogen were located in a difference Fourier map. The bond distances to H were fixed at 0.97 Å for the carbon atoms and the H atoms were allowed to ride on their bonded C atoms with U_iso = 1.2U_eq(C). Those of the nitrogen atoms were freely refined with a distance restraint of 0.8 Å.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: CrystalMaker (CrystalMaker Software, 2003) and ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures

	Fig. 1. Packing of the title compound illustrating the hydrogen bonding of the nitrate anion and the protonated DABCO nitrogen.
	Fig. 2. ORTEP drawing of title compound. Ellipsoids are shown at the 50% probability level. Hydrogen atoms are omitted for clarity.

1,4-Diazoniabicyclo[2.2.2]octane dinitrate

Crystal data

C6H14N2^2+·2NO3^−	F(000) = 504
Mr = 238.21	Dx = 1.578 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2891 reflections
a = 11.4887 (4) Å	θ = 2.4–30.4°
b = 6.8821 (2) Å	µ = 0.14 mm^−1
c = 12.6838 (5) Å	T = 293 K
β = 91.247 (5)°	Block, colourless
V = 1002.62 (6) Å^3	0.2 × 0.2 × 0.1 mm
Z = 4

Data collection

Bruker APEX II CCD diffractometer	2891 independent reflections
Radiation source: fine-focus sealed tube	1701 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.046
ω and φ scans	θmax = 30.4°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2002)	h = −16→16
Tmin = 0.972, Tmax = 0.986	k = −9→9
18932 measured reflections	l = −18→18

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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.156	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0711P)^2 + 0.2134P] where P = (Fo^2 + 2Fc^2)/3
2891 reflections	(Δ/σ)max < 0.001
153 parameters	Δρmax = 0.33 e Å^−3
2 restraints	Δρmin = −0.21 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	0.93691 (19)	0.7655 (3)	0.25071 (15)	0.0463 (5)
H1A	0.9694	0.6490	0.2827	0.056*
H1B	0.8701	0.7286	0.2072	0.056*
C2	0.90005 (17)	0.9055 (3)	0.33541 (16)	0.0421 (5)
H2A	0.8164	0.9245	0.3313	0.051*
H2B	0.9200	0.8530	0.4044	0.051*
C3	1.08900 (18)	1.0677 (3)	0.33089 (16)	0.0457 (5)
H3A	1.1094	1.0248	0.4018	0.055*
H3B	1.1280	1.1903	0.3183	0.055*
C4	1.12770 (17)	0.9181 (3)	0.25179 (16)	0.0463 (5)
H4A	1.1883	0.9719	0.2084	0.056*
H4B	1.1588	0.8049	0.2882	0.056*
C5	0.9751 (2)	1.0361 (3)	0.13096 (14)	0.0422 (5)
H5A	0.9122	0.9972	0.0833	0.051*
H5B	1.0342	1.1006	0.0902	0.051*
C6	0.9296 (2)	1.1734 (3)	0.21419 (16)	0.0491 (5)
H6A	0.9641	1.3010	0.2060	0.059*
H6B	0.8458	1.1861	0.2064	0.059*
N1	0.84994 (15)	0.4322 (2)	0.48142 (13)	0.0409 (4)
N2	0.96035 (14)	1.0939 (2)	0.32027 (12)	0.0350 (4)
N3	1.02573 (14)	0.8620 (2)	0.18482 (11)	0.0333 (4)
N4	0.63928 (13)	0.0013 (2)	0.54168 (14)	0.0405 (4)
O1	0.92260 (13)	0.2997 (2)	0.50023 (11)	0.0527 (4)
O2	0.81216 (19)	0.5294 (3)	0.55311 (17)	0.0858 (7)
O3	0.81960 (15)	0.4576 (2)	0.38782 (13)	0.0601 (5)
O4	0.59975 (15)	−0.1572 (2)	0.50989 (12)	0.0583 (5)
O5	0.64042 (15)	0.0298 (3)	0.63862 (13)	0.0630 (5)
O6	0.67368 (18)	0.1223 (3)	0.47992 (16)	0.0897 (7)
H30	1.0467 (19)	0.785 (3)	0.1429 (15)	0.049 (7)*
H20	0.9441 (19)	1.169 (3)	0.3691 (15)	0.051 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0612 (13)	0.0367 (10)	0.0413 (11)	−0.0152 (9)	0.0087 (9)	−0.0028 (9)
C2	0.0408 (11)	0.0442 (11)	0.0418 (10)	−0.0041 (9)	0.0109 (8)	0.0018 (9)
C3	0.0417 (11)	0.0502 (12)	0.0452 (11)	−0.0082 (9)	−0.0008 (8)	−0.0153 (9)
C4	0.0377 (10)	0.0580 (13)	0.0433 (11)	0.0053 (9)	0.0032 (8)	−0.0100 (10)
C5	0.0625 (13)	0.0363 (10)	0.0278 (9)	0.0065 (9)	0.0019 (8)	0.0027 (8)
C6	0.0726 (15)	0.0342 (10)	0.0407 (11)	0.0165 (10)	0.0049 (10)	0.0040 (8)
N1	0.0438 (9)	0.0361 (9)	0.0432 (10)	−0.0021 (7)	0.0114 (7)	−0.0060 (7)
N2	0.0460 (9)	0.0304 (8)	0.0288 (8)	0.0037 (7)	0.0061 (6)	−0.0078 (6)
N3	0.0435 (9)	0.0272 (8)	0.0292 (8)	0.0038 (6)	0.0051 (6)	−0.0065 (6)
N4	0.0344 (8)	0.0420 (9)	0.0448 (9)	−0.0061 (7)	−0.0030 (7)	0.0090 (8)
O1	0.0566 (9)	0.0528 (9)	0.0486 (9)	0.0135 (8)	−0.0027 (7)	−0.0027 (7)
O2	0.0961 (15)	0.0754 (13)	0.0876 (14)	0.0042 (11)	0.0411 (11)	−0.0400 (11)
O3	0.0643 (10)	0.0609 (10)	0.0551 (10)	−0.0022 (8)	−0.0001 (8)	0.0195 (8)
O4	0.0795 (12)	0.0405 (9)	0.0549 (10)	−0.0036 (8)	−0.0013 (8)	−0.0062 (7)
O5	0.0695 (11)	0.0744 (12)	0.0444 (9)	−0.0063 (9)	−0.0102 (7)	−0.0050 (8)
O6	0.0924 (15)	0.0900 (15)	0.0867 (14)	−0.0397 (12)	0.0023 (11)	0.0444 (12)

Geometric parameters (Å, º)

C1—N3	1.489 (2)	C5—C6	1.518 (3)
C1—C2	1.510 (3)	C5—H5A	0.9700
C1—H1A	0.9700	C5—H5B	0.9700
C1—H1B	0.9700	C6—N2	1.488 (3)
C2—N2	1.484 (3)	C6—H6A	0.9700
C2—H2A	0.9700	C6—H6B	0.9700
C2—H2B	0.9700	N1—O2	1.217 (2)
C3—N2	1.492 (3)	N1—O3	1.242 (2)
C3—C4	1.511 (3)	N1—O1	1.255 (2)
C3—H3A	0.9700	N2—H20	0.832 (15)
C3—H3B	0.9700	N3—H30	0.793 (16)
C4—N3	1.483 (3)	N4—O6	1.215 (2)
C4—H4A	0.9700	N4—O5	1.245 (2)
C4—H4B	0.9700	N4—O4	1.245 (2)
C5—N3	1.491 (2)
N3—C1—C2	108.72 (15)	N3—C5—H5B	110.0
N3—C1—H1A	109.9	C6—C5—H5B	110.0
C2—C1—H1A	109.9	H5A—C5—H5B	108.4
N3—C1—H1B	109.9	N2—C6—C5	108.74 (15)
C2—C1—H1B	109.9	N2—C6—H6A	109.9
H1A—C1—H1B	108.3	C5—C6—H6A	109.9
N2—C2—C1	109.03 (14)	N2—C6—H6B	109.9
N2—C2—H2A	109.9	C5—C6—H6B	109.9
C1—C2—H2A	109.9	H6A—C6—H6B	108.3
N2—C2—H2B	109.9	O2—N1—O3	122.6 (2)
C1—C2—H2B	109.9	O2—N1—O1	120.3 (2)
H2A—C2—H2B	108.3	O3—N1—O1	117.11 (16)
N2—C3—C4	109.12 (15)	C2—N2—C6	109.64 (16)
N2—C3—H3A	109.9	C2—N2—C3	110.30 (15)
C4—C3—H3A	109.9	C6—N2—C3	109.95 (16)
N2—C3—H3B	109.9	C2—N2—H20	109.6 (16)
C4—C3—H3B	109.9	C6—N2—H20	113.0 (16)
H3A—C3—H3B	108.3	C3—N2—H20	104.3 (16)
N3—C4—C3	108.51 (15)	C4—N3—C1	109.69 (15)
N3—C4—H4A	110.0	C4—N3—C5	110.40 (16)
C3—C4—H4A	110.0	C1—N3—C5	110.50 (16)
N3—C4—H4B	110.0	C4—N3—H30	108.1 (16)
C3—C4—H4B	110.0	C1—N3—H30	107.4 (17)
H4A—C4—H4B	108.4	C5—N3—H30	110.7 (16)
N3—C5—C6	108.56 (15)	O6—N4—O5	122.1 (2)
N3—C5—H5A	110.0	O6—N4—O4	120.9 (2)
C6—C5—H5A	110.0	O5—N4—O4	116.99 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H30···O4^i	0.79 (2)	2.01 (2)	2.778 (2)	163 (2)
N3—H30···O5^i	0.79 (2)	2.42 (2)	3.063 (2)	139 (2)
N2—H20···O1^ii	0.83 (2)	1.91 (2)	2.729 (2)	167 (2)
N2—H20···O3^ii	0.83 (2)	2.46 (2)	3.111 (2)	136 (2)

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