Bis(adamantan-1-aminium) carbonate

Abstract

In the title compound, 2C₁₀H₁₈N⁺·CO₃ ²⁻, the adamantan-1-aminium cation forms three N—H⋯O hydrogen bonds to three carbonate ions, resulting in a layer parallel to (001) with the adamantane groups located on its surface so that adjacent layers form only C—H⋯H—C contacts. The carbonate anions occupy special positions of 32 symmetry, whereas the adamantan-1-aminium cations occupy special positions of 3 symmetry.

Related literature  

For related structures, see: de Vries et al. (2011 ▶); Mullica et al. (1999 ▶); He & Wen (2006 ▶); Liu et al. (2009 ▶); Zhao et al. (2003 ▶). For applications of adamantane–ammonium salts in virology, see: Hoffmann (1973 ▶); Dolin et al. (1982 ▶); Bright et al. (2005 ▶); Betakova (2007 ▶). For applications of amines for the capture of CO₂ from the atmosphere, see: Yang et al. (2008 ▶).

Experimental  

Crystal data  

• 2C₁₀H₁₈N⁺·CO₃ ²⁻

• M _r = 364.52

• Trigonal,

• a = 6.4340 (6) Å

• c = 25.474 (2) Å

• V = 913.25 (14) ų

• Z = 2

• Mo Kα radiation

• μ = 0.09 mm⁻¹

• T = 173 K

• 0.30 × 0.22 × 0.08 mm

Data collection  

• Bruker APEXII CCD diffractometer

• 3187 measured reflections

• 629 independent reflections

• 493 reflections with I > 2σ(I)

• R _int = 0.062

Refinement  

• R[F ² > 2σ(F ²)] = 0.042

• wR(F ²) = 0.107

• S = 1.08

• 629 reflections

• 45 parameters

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.22 e Å⁻³

• Δρ_min = −0.18 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT-Plus (Bruker, 2005 ▶); data reduction: SAINT-Plus and XPREP (Bruker 2005 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶), Mercury (Macrae et al., 2008 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶) and PLATON.

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536812011828/gk2467Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1i	0.999 (16)	1.778 (15)	2.764 (1)	168.7 (18)

Symmetry code: (i) .

supplementary crystallographic information

Comment

It has been reported that 1-aminoadamantane hydrochloride (marketed as Symmetrel) is effective in the prevention and treatment of the influenza (A) virus (Hoffmann, 1973; Dolin et al., 1982; Bright et al., 2005). However recent studies suggest that the virus is becoming increasingly resistant to this anti-influenza drug (Betakova, 2007).

In an attempt to crystallize pure 1-aminoadamantane from ethanol we obtained instead adamantan-1-aminium carbonate, illustrated in Fig. 1, suggesting that the amine had captured atmospheric CO₂. We report the structure here. It is known that organic amines can trap CO₂ as the ammonium carbonate salt and this property is being explored as a way to capture carbon dioxide from the atmosphere (Yang et al., 2008).

Each carbonate ion of the title compound forms hydrogen bonds to six adamantane-ammonium ions, as shown in Fig. 2, forming a two-dimensional layer of adamantan-1-aminium carbonates parallel to (001). The hydrophobic adamantane layers interact with the neighbouring layers of adamantane-ammonium molecules via C—H···H–C contacts (see Fig. 3).

It is noted here that the structure of adamantan-1-aminium bicarbonate (Liu et al., 2009) reported in the literature is isomorphous to adamantan-1-aminium nitrate (Zhao et al., 2003). The former structure has unusually short H···H intermolecular contacts between NH₃⁺ group H atom and bicarbonate H atom of 1.50 Å In addition the geometry of the hydrogen carbonate ion is very similar to that of the nitrate ion. A re-investigation of these structures is warranted.

Experimental

Crystals were grown by slow evaporation of an ethanol solution of the title compound, 0.500 g in 10 ml of ethanol, and afforded colourless plates after three days under ambient conditions. Crystals decompose, with an emission of gas bubbles (presumably CO₂), at 423–428 K.

Refinement

The N-bound H atom was placed according to the observed electron density and was allowed to refine freely. The remaining H atoms were positioned geometrically and allowed to ride on their respective parent atoms, with C—H bond lengths of 1.00 (methine) and 0.99 Å (methylene CH₂) and with U_iso(H) = 1.2 times U_eq(C).

Figures

Fig. 1.

The molecular structure of the title compound. Displacement ellipsoids are shown at the 50% probability level. The atoms C2f to C4f are generated by the symmetry (1-y,x-y,z); C2g to C4g by (1-x+y, 1-x,z); O1a by (-y,x-y,z) and O2b by (-x+y,-x,z).

Fig. 2.

Intermolecular N—H···O hydrogen bonded (dashed lines) layers along [001] showing only the C-NH3 and CO3 groups for clarity.

Fig. 3.

A view down the b axis of the unit cell of the title compound showing the hydrogen bonded layers. Notice that the carbonate ions occupy sites with 32 symmetry whereas cations occupy the sites of 3 symmetry.

Crystal data

2C10H18N+·CO32−	Dx = 1.326 Mg m−3
Mr = 364.52	Mo Kα radiation, λ = 0.71069 Å
Trigonal, P3c1	Cell parameters from 819 reflections
Hall symbol: -P 3 2"c	θ = 3.2–25.8°
a = 6.4340 (6) Å	µ = 0.09 mm−1
c = 25.474 (2) Å	T = 173 K
V = 913.25 (14) Å3	Prism, colourless
Z = 2	0.30 × 0.22 × 0.08 mm
F(000) = 400

Data collection

Bruker APEXII CCD diffractometer	Rint = 0.062
Graphite monochromator	θmax = 26.4°, θmin = 1.6°
φ and ω scans	h = −8→5
3187 measured reflections	k = −2→8
629 independent reflections	l = −31→31
493 reflections with I > 2σ(I)

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.107	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ2(Fo2) + (0.0587P)2 + 0.010P] where P = (Fo2 + 2Fc2)/3
629 reflections	(Δ/σ)max < 0.001
45 parameters	Δρmax = 0.22 e Å−3
0 restraints	Δρmin = −0.18 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	0.6667	0.3333	0.16486 (9)	0.0236 (6)
C2	0.9213 (2)	0.5034 (2)	0.14518 (6)	0.0278 (4)
H2A	1.032	0.4505	0.1584	0.033*
H2B	0.977	0.6678	0.1583	0.033*
C3	0.9215 (2)	0.5033 (3)	0.08498 (6)	0.0309 (4)
H3	1.0877	0.614	0.0719	0.037*
C4	0.8365 (3)	0.2482 (3)	0.06502 (6)	0.0346 (4)
H4A	0.838	0.2474	0.0262	0.042*
H4B	0.9464	0.1932	0.0777	0.042*
C5	0	0	0.25	0.0219 (7)
N1	0.6667	0.3333	0.22372 (8)	0.0278 (5)
O1	0	0.1993 (2)	0.25	0.0343 (4)
H1	0.732 (4)	0.502 (3)	0.2358 (7)	0.060 (5)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.0198 (8)	0.0198 (8)	0.0312 (12)	0.0099 (4)	0	0
C2	0.0195 (8)	0.0205 (7)	0.0415 (9)	0.0087 (6)	−0.0018 (6)	−0.0014 (6)
C3	0.0217 (8)	0.0262 (8)	0.0404 (9)	0.0085 (6)	0.0061 (6)	0.0039 (6)
C4	0.0317 (9)	0.0350 (9)	0.0397 (8)	0.0185 (8)	0.0055 (6)	−0.0016 (7)
C5	0.0214 (10)	0.0214 (10)	0.0228 (15)	0.0107 (5)	0	0
N1	0.0253 (7)	0.0253 (7)	0.0328 (11)	0.0127 (3)	0	0
O1	0.0299 (8)	0.0221 (6)	0.0536 (10)	0.0149 (4)	−0.0091 (7)	−0.0045 (3)

Geometric parameters (Å, º)

C1—N1	1.500 (3)	C3—C4	1.534 (2)
C1—C2	1.5295 (14)	C3—H3	1
C2—C3	1.5335 (19)	C4—H4A	0.99
C2—H2A	0.99	C4—H4B	0.99
C2—H2B	0.99	C5—O1	1.2820 (13)
C3—C4i	1.532 (2)	N1—H1	0.999 (16)
N1—C1—C2	109.13 (9)	C2—C3—C4	109.40 (12)
C2ii—C1—C2	109.81 (9)	C2—C3—H3	109.5
C1—C2—C3	109.18 (12)	C4—C3—H3	109.5
C1—C2—H2A	109.8	C3ii—C4—C3	109.57 (13)
C3—C2—H2A	109.8	C3—C4—H4A	109.8
C1—C2—H2B	109.8	C3—C4—H4B	109.8
C3—C2—H2B	109.8	H4A—C4—H4B	108.2
H2A—C2—H2B	108.3	O1iii—C5—O1	120
C4i—C3—C2	109.29 (11)	C1—N1—H1	107.9 (11)
C4i—C3—C4	109.58 (14)
N1—C1—C2—C3	179.92 (8)	C1—C2—C3—C4	−59.84 (12)
C2ii—C1—C2—C3	60.34 (13)	C4i—C3—C4—C3ii	−59.76 (18)
C2i—C1—C2—C3	−60.50 (13)	C2—C3—C4—C3ii	60.04 (15)
C1—C2—C3—C4i	60.13 (13)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1iv	0.999 (16)	1.778 (15)	2.7644 (11)	168.7 (18)

Symmetry code: (iv) −y+1, x−y+1, z.