Adamantane-1-ammonium acetate

Vries, E.J.C. de; Gamble, C.; Nowakowska, M.

doi:10.1107/S1600536811012670

organic compounds

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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page o1339

doi:10.1107/S1600536811012670

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Adamantane-1-ammonium acetate

Elise J. C. de Vries,^a ^* Caryn Gamble ^a and Monika Nowakowska ^a

^aMolecular Science Institute, School of Chemistry, University of the Witwatersrand, PO Wits, 2050 Johannesburg, South Africa
^*Correspondence e-mail: ejc.devries@gmail.com

(Received 25 March 2011; accepted 5 April 2011; online 7 May 2011)

In the title compound, C₁₀H₁₈N⁺·C₂H₃O₂⁻, the ammonium H atoms of the cation are linked to three acetate anions via N—H⋯O hydrogen bonds, forming a chain structure extending along the b axis.

Related literature

For related structures, see: Mullica et al. (1999 ); He & Wen (2006 ). For their applications in virology, see: Hoffmann (1973); Dolin et al. (1982 ); Bright et al. (2005 ); Betakova (2007 ). For graph-set analysis, see: Bernstein et al. (1995 ). For Csp³—O bond lengths, see: Orpen et al. (1989 ).

Experimental

Crystal data

C₁₀H₁₈N⁺·C₂H₃O₂⁻
M_r = 211.30
Monoclinic, C 2/c
a = 25.7625 (12) Å
b = 6.4852 (3) Å
c = 17.3970 (9) Å
β = 127.377 (2)°
V = 2309.8 (2) Å³
Z = 8
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 296 K
0.40 × 0.07 × 0.05 mm

Data collection

Bruker APEXII CCD diffractometer
15067 measured reflections
2261 independent reflections
1471 reflections with I > 2σ(I)
R_int = 0.077

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.134
S = 1.01
2261 reflections
149 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O1	0.99 (4)	1.80 (4)	2.777 (3)	171 (3)
N1—H1B⋯O2ⁱ	0.94 (3)	1.83 (3)	2.758 (3)	170 (3)
N1—H1C⋯O1ⁱⁱ	0.97 (2)	1.82 (2)	2.786 (2)	171 (3)
Symmetry codes: (i) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2005 ); cell refinement: SAINT-NT (Bruker, 2005); data reduction: SAINT-NT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ; Atwood & Barbour, 2003 ); software used to prepare material for publication: X-SEED.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811012670/zs2106sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811012670/zs2106Isup2.hkl

checkCIF report

Comment top

It is well established that 1-aminoadamantane hydrochloride (amantadine hydrochloride: trade name 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). The investigation of new derivatives of this compound is still important. Here we report the crystal structure of adamantane-1-ammonium acetate (I), illustrated in Fig. 1.

The asymmetric unit of (I) contains an adamantane-1-ammonium cation and an acetate anion. In the cation, the exocyclic C—N bond is 1.500 (3) Å. The C—C bonds of the adamantane skeleton range from 1.527 (3) to 1.537 (3) Å, with a mean value of 1.531 Å. The C—C—C bond angles range from 109.05 (18) to 110.10 (18) °, with a mean value of 109.5 °, which is in good agreement with the value for a tetrahedral angle. In the anion, the C(sp3)-O distances of 1.266 (3) and 1.240 (3) Å are in the range of values given in the literature (Orpen et al., 1989).

The crystal structure is stabilized by a network of intermolecular charge assisted carbonyl-to-amine hydrogen bonds. All ammonium hydrogen atoms are involved in hydrogen bonding with the oxygen atoms of the acetate anion (Table 1). The hydrogen-bonding scheme can be described as a nine membered ring motif with graph-set notation R³₄(10) (Bernstein et al., 1995). This results in the formation of a one-dimensional chain structure parallel to the b axis of the unit cell (Fig. 2).

Related literature top

For related structures, see: Mullica et al. (1999); He & Wen (2006). For their applications in virology, see: Hoffmann (1973); Dolin et al. (1982); Bright et al. (2005); Betakova (2007). For graph-set analysis, see: Bernstein et al. (1995). For Csp³—O bond lengths, see: Orpen et al. (1989).

Experimental top

Adamantadine hydrochloride (10 mg) was dissolved in three drops of glacial acetic acid and deionized water. The solution was allowed to undergo slow evaporation. Single crystals of (I) suitable for X-ray diffraction anlaysis precipitated after a few days.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-NT (Bruker, 2005); data reduction: SAINT-NT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001; Atwood & Barbour, 2003); software used to prepare material for publication: X-SEED (Barbour, 2001; Atwood & Barbour, 2003).

Figures top

	Fig. 1. The atom numbering scheme of compound (I). Displacement ellipsoids are drawn at 50% probability level.
	Fig. 2. A perspective diagram viewed down the c axis of the molecular packing arrangement in (I), displaying the N–H···O hydrogen-bonding contacts as red dashed lines. Hydrogen atoms not involved in hydrogen bonding are omitted.

Adamantane-1-ammonium acetate top

Crystal data top

C₁₀H₁₈N⁺·C₂H₃O₂⁻	F(000) = 928
M_r = 211.30	D_x = 1.215 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1706 reflections
a = 25.7625 (12) Å	θ = 3.0–25.1°
b = 6.4852 (3) Å	µ = 0.08 mm⁻¹
c = 17.3970 (9) Å	T = 296 K
β = 127.377 (2)°	Needle, colourless
V = 2309.8 (2) Å³	0.40 × 0.07 × 0.05 mm
Z = 8

Data collection top

Bruker APEXII CCD diffractometer	1471 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.077
Graphite monochromator	θ_max = 26.0°, θ_min = 2.0°
ϕ and ω scans	h = −31→31
15067 measured reflections	k = −8→8
2261 independent reflections	l = −21→20

Refinement top

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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.134	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ²(F_o²) + (0.0546P)² + 1.9569P] where P = (F_o² + 2F_c²)/3
2261 reflections	(Δ/σ)_max < 0.001
149 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₁₀H₁₈N⁺·C₂H₃O₂⁻	V = 2309.8 (2) Å³
M_r = 211.30	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 25.7625 (12) Å	µ = 0.08 mm⁻¹
b = 6.4852 (3) Å	T = 296 K
c = 17.3970 (9) Å	0.40 × 0.07 × 0.05 mm
β = 127.377 (2)°

Data collection top

Bruker APEXII CCD diffractometer	1471 reflections with I > 2σ(I)
15067 measured reflections	R_int = 0.077
2261 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.134	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	Δρ_max = 0.23 e Å⁻³
2261 reflections	Δρ_min = −0.21 e Å⁻³
149 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

	x	y	z	U_iso*/U_eq
O1	0.32323 (7)	0.4743 (2)	0.78287 (11)	0.0299 (4)
N1	0.19171 (10)	0.5670 (3)	0.68283 (14)	0.0240 (5)
C1	0.16138 (10)	0.5443 (3)	0.57747 (15)	0.0218 (5)
O2	0.36698 (8)	0.7678 (2)	0.78092 (12)	0.0347 (4)
C2	0.17908 (11)	0.3319 (3)	0.56130 (15)	0.0252 (5)
H2B	0.2271	0.3184	0.6007	0.030*
H2A	0.1628	0.2229	0.5815	0.030*
C3	0.14826 (10)	0.3069 (3)	0.45404 (15)	0.0264 (5)
H3A	0.1595	0.1679	0.4430	0.032*
C4	0.07403 (11)	0.3266 (4)	0.39419 (17)	0.0327 (6)
H4A	0.0570	0.2184	0.4137	0.039*
H4B	0.0537	0.3075	0.3248	0.039*
C5	0.05648 (11)	0.5400 (4)	0.41012 (17)	0.0299 (6)
H5A	0.0079	0.5534	0.3705	0.036*
C6	0.08313 (11)	0.7061 (4)	0.38012 (17)	0.0315 (6)
H6A	0.0715	0.8443	0.3896	0.038*
H6B	0.0633	0.6903	0.3107	0.038*
C7	0.15743 (11)	0.6867 (3)	0.44084 (16)	0.0270 (5)
H7A	0.1746	0.7962	0.4213	0.032*
C8	0.18804 (10)	0.7119 (3)	0.54849 (15)	0.0243 (5)
H8A	0.2362	0.7003	0.5881	0.029*
H8B	0.1773	0.8496	0.5598	0.029*
C9	0.08731 (10)	0.5654 (4)	0.51785 (16)	0.0267 (5)
H9A	0.0761	0.7024	0.5291	0.032*
H9B	0.0701	0.4585	0.5376	0.032*
C10	0.17474 (11)	0.4742 (3)	0.42404 (17)	0.0287 (6)
H10A	0.2227	0.4608	0.4626	0.034*
H10B	0.1554	0.4578	0.3549	0.034*
C11	0.36787 (11)	0.5780 (3)	0.79083 (16)	0.0251 (5)
C12	0.42684 (13)	0.4608 (4)	0.8153 (2)	0.0465 (7)
H12A	0.4638	0.4855	0.8832	0.070*
H12B	0.4381	0.5079	0.7736	0.070*
H12C	0.4169	0.3130	0.8052	0.070*
H1A	0.2392 (15)	0.544 (4)	0.723 (2)	0.055 (8)*
H1B	0.1765 (12)	0.461 (4)	0.7010 (17)	0.037 (7)*
H1C	0.1835 (11)	0.704 (3)	0.6961 (17)	0.043 (7)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0225 (9)	0.0286 (9)	0.0383 (10)	0.0000 (7)	0.0183 (8)	0.0033 (7)
N1	0.0244 (11)	0.0242 (11)	0.0265 (10)	0.0001 (9)	0.0170 (10)	0.0004 (9)
C1	0.0183 (11)	0.0227 (11)	0.0218 (11)	−0.0014 (9)	0.0109 (10)	0.0002 (9)
O2	0.0440 (11)	0.0258 (9)	0.0491 (11)	0.0017 (8)	0.0360 (9)	0.0018 (8)
C2	0.0240 (12)	0.0228 (11)	0.0282 (12)	0.0003 (10)	0.0155 (11)	0.0017 (10)
C3	0.0261 (13)	0.0210 (12)	0.0313 (13)	0.0004 (10)	0.0170 (11)	−0.0029 (10)
C4	0.0267 (13)	0.0352 (13)	0.0307 (13)	−0.0096 (11)	0.0145 (11)	−0.0073 (11)
C5	0.0171 (12)	0.0380 (14)	0.0286 (12)	−0.0004 (10)	0.0108 (10)	0.0007 (11)
C6	0.0287 (14)	0.0342 (14)	0.0277 (12)	0.0070 (11)	0.0151 (11)	0.0067 (11)
C7	0.0289 (13)	0.0265 (12)	0.0307 (13)	−0.0009 (10)	0.0208 (11)	0.0036 (10)
C8	0.0228 (12)	0.0206 (11)	0.0312 (12)	−0.0017 (9)	0.0173 (11)	−0.0015 (9)
C9	0.0218 (12)	0.0295 (13)	0.0326 (13)	0.0001 (10)	0.0185 (11)	0.0009 (10)
C10	0.0260 (13)	0.0354 (14)	0.0269 (12)	−0.0003 (10)	0.0171 (11)	−0.0038 (10)
C11	0.0258 (13)	0.0276 (12)	0.0255 (12)	0.0022 (10)	0.0174 (11)	0.0001 (10)
C12	0.0401 (16)	0.0417 (16)	0.072 (2)	0.0117 (13)	0.0416 (16)	0.0143 (14)

Geometric parameters (Å, º) top

O1—C11	1.265 (3)	C5—C9	1.537 (3)
N1—C1	1.501 (3)	C5—H5A	1.0000
N1—H1A	0.98 (3)	C6—C7	1.530 (3)
N1—H1B	0.94 (3)	C6—H6A	0.9900
N1—H1C	0.976 (17)	C6—H6B	0.9900
C1—C8	1.526 (3)	C7—C10	1.530 (3)
C1—C9	1.527 (3)	C7—C8	1.537 (3)
C1—C2	1.530 (3)	C7—H7A	1.0000
O2—C11	1.241 (3)	C8—H8A	0.9900
C2—C3	1.530 (3)	C8—H8B	0.9900
C2—H2B	0.9900	C9—H9A	0.9900
C2—H2A	0.9900	C9—H9B	0.9900
C3—C4	1.530 (3)	C10—H10A	0.9900
C3—C10	1.532 (3)	C10—H10B	0.9900
C3—H3A	1.0000	C11—C12	1.510 (3)
C4—C5	1.533 (3)	C12—H12A	0.9800
C4—H4A	0.9900	C12—H12B	0.9800
C4—H4B	0.9900	C12—H12C	0.9800
C5—C6	1.529 (3)

C1—N1—H1A	110.6 (16)	C7—C6—H6A	109.7
C1—N1—H1B	109.1 (15)	C5—C6—H6B	109.7
H1A—N1—H1B	104 (2)	C7—C6—H6B	109.7
C1—N1—H1C	110.6 (14)	H6A—C6—H6B	108.2
H1A—N1—H1C	109 (2)	C6—C7—C10	109.25 (18)
H1B—N1—H1C	113 (2)	C6—C7—C8	109.50 (18)
N1—C1—C8	109.19 (17)	C10—C7—C8	109.58 (18)
N1—C1—C9	109.28 (17)	C6—C7—H7A	109.5
C8—C1—C9	109.84 (17)	C10—C7—H7A	109.5
N1—C1—C2	108.69 (17)	C8—C7—H7A	109.5
C8—C1—C2	109.66 (17)	C1—C8—C7	109.02 (17)
C9—C1—C2	110.15 (17)	C1—C8—H8A	109.9
C3—C2—C1	109.15 (17)	C7—C8—H8A	109.9
C3—C2—H2B	109.9	C1—C8—H8B	109.9
C1—C2—H2B	109.9	C7—C8—H8B	109.9
C3—C2—H2A	109.9	H8A—C8—H8B	108.3
C1—C2—H2A	109.9	C1—C9—C5	109.05 (18)
H2B—C2—H2A	108.3	C1—C9—H9A	109.9
C2—C3—C4	109.27 (19)	C5—C9—H9A	109.9
C2—C3—C10	109.36 (18)	C1—C9—H9B	109.9
C4—C3—C10	109.87 (19)	C5—C9—H9B	109.9
C2—C3—H3A	109.4	H9A—C9—H9B	108.3
C4—C3—H3A	109.4	C7—C10—C3	109.35 (18)
C10—C3—H3A	109.4	C7—C10—H10A	109.8
C3—C4—C5	109.68 (18)	C3—C10—H10A	109.8
C3—C4—H4A	109.7	C7—C10—H10B	109.8
C5—C4—H4A	109.7	C3—C10—H10B	109.8
C3—C4—H4B	109.7	H10A—C10—H10B	108.3
C5—C4—H4B	109.7	O2—C11—O1	125.0 (2)
H4A—C4—H4B	108.2	O2—C11—C12	118.0 (2)
C6—C5—C4	109.34 (19)	O1—C11—C12	117.1 (2)
C6—C5—C9	109.52 (18)	C11—C12—H12A	109.5
C4—C5—C9	109.03 (18)	C11—C12—H12B	109.5
C6—C5—H5A	109.6	H12A—C12—H12B	109.5
C4—C5—H5A	109.6	C11—C12—H12C	109.5
C9—C5—H5A	109.6	H12A—C12—H12C	109.5
C5—C6—C7	109.83 (18)	H12B—C12—H12C	109.5
C5—C6—H6A	109.7

N1—C1—C2—C3	179.86 (18)	C9—C1—C8—C7	−60.8 (2)
C8—C1—C2—C3	−60.8 (2)	C2—C1—C8—C7	60.4 (2)
C9—C1—C2—C3	60.2 (2)	C6—C7—C8—C1	59.8 (2)
C1—C2—C3—C4	−59.9 (2)	C10—C7—C8—C1	−60.0 (2)
C1—C2—C3—C10	60.4 (2)	N1—C1—C9—C5	−179.49 (17)
C2—C3—C4—C5	60.6 (2)	C8—C1—C9—C5	60.7 (2)
C10—C3—C4—C5	−59.4 (2)	C2—C1—C9—C5	−60.1 (2)
C3—C4—C5—C6	59.2 (2)	C6—C5—C9—C1	−59.7 (2)
C3—C4—C5—C9	−60.5 (2)	C4—C5—C9—C1	59.9 (2)
C4—C5—C6—C7	−59.9 (2)	C6—C7—C10—C3	−60.0 (2)
C9—C5—C6—C7	59.5 (2)	C8—C7—C10—C3	59.9 (2)
C5—C6—C7—C10	60.5 (2)	C2—C3—C10—C7	−60.2 (2)
C5—C6—C7—C8	−59.5 (2)	C4—C3—C10—C7	59.8 (2)
N1—C1—C8—C7	179.39 (17)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1	0.99 (4)	1.80 (4)	2.777 (3)	171 (3)
N1—H1B···O2ⁱ	0.94 (3)	1.83 (3)	2.758 (3)	170 (3)
N1—H1C···O1ⁱⁱ	0.97 (2)	1.82 (2)	2.786 (2)	171 (3)

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

Experimental details

Crystal data
Chemical formula	C₁₀H₁₈N⁺·C₂H₃O₂⁻
M_r	211.30
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	296
a, b, c (Å)	25.7625 (12), 6.4852 (3), 17.3970 (9)
β (°)	127.377 (2)
V (Å³)	2309.8 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.40 × 0.07 × 0.05

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	15067, 2261, 1471
R_int	0.077
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.134, 1.01
No. of reflections	2261
No. of parameters	149
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.21

Computer programs: APEX2 (Bruker, 2005), SAINT-NT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001; Atwood & Barbour, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1	0.99 (4)	1.80 (4)	2.777 (3)	171 (3)
N1—H1B···O2ⁱ	0.94 (3)	1.83 (3)	2.758 (3)	170 (3)
N1—H1C···O1ⁱⁱ	0.97 (2)	1.82 (2)	2.786 (2)	171 (3)

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

Acknowledgements

The authors thans the National Research Foundation of South Africa and the University of the Witwatersrand for financial support.

References

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