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Adamantane-1-ammonium acetate

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[Mullica, D. F., Scott, T. G., Farmer, J. M. & Kautz, J. A. (1999). J. Chem. Crystallogr. 29, 845-848.]); He & Wen (2006[He, Y.-H. & Wen, Y.-H. (2006). Acta Cryst. E62, o1312-o1313.]). For their applications in virology, see: Hoffmann (1973)[Hoffmann, C. E. (1973). Selective Inhibitors of Viral Functions, edited by W. A. Carter, p. 199. Cleveland, USA: CRC Press.]; Dolin et al. (1982[Dolin, R., Reichman, R. C., Madore, H. P., Maynard, R., Lindon, P. M. & Weber-Jones, J. (1982). N. Engl. J. Med. 307, 580-584.]); Bright et al. (2005[Bright, R. A., Medina, M. J., Xu, X. Y., Gilda, P. O., Wallis, T. R., Davis, X. H. M., Povinelli, L., Cox, N. J. & Klimov, A. I. (2005). Lancet, 366, 1175-1181.]); Betakova (2007[Betakova, T. (2007). Curr. Pharm. Des. 13, 3231-3235.]). For graph-set analysis, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 35, 1555-1573.]). For Csp3—O bond lengths, see: Orpen et al. (1989[Orpen, A. G., Brammer, L., Allen, F. H., Kennard, O., Watson, D. G. & Taylor, R. (1989). J. Chem. Soc. Dalton Trans. pp. S1-83.]).

[Scheme 1]

Experimental

Crystal data
  • C10H18N+·C2H3O2

  • Mr = 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)

  • Rint = 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

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA 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[Bruker (2005). APEX2 and SAINT-NT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-NT (Bruker, 2005[Bruker (2005). APEX2 and SAINT-NT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-NT; 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: X-SEED (Barbour, 2001[Barbour, L. J. (2001). J. Supramol. Chem. 1, 189-191.]; Atwood & Barbour, 2003[Atwood, J. L. & Barbour, L. J. (2003). Cryst. Growth Des. 3, 3-8.]); software used to prepare material for publication: X-SEED.

Supporting information


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.

Refinement top

The ammonium H atoms were placed according to the observed electron density and allowed to refine freely. A distance constraint was placed on one of the N—H bonds [N1–H1C, 0.95 (2) Å]. The remaining H atoms were positioned geometrically and allowed to ride on their respective parent atoms, with C—H bond lengths of 0.99 (aromatic CH) 1.00 (methine CH), 0.99 (methylene CH2) and 0.98 Å (methyl CH3), and with Uiso(H) = 1.2 or 1.5 times Ueq(C).

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
[Figure 1] Fig. 1. The atom numbering scheme of compound (I). Displacement ellipsoids are drawn at 50% probability level.
[Figure 2] 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+·C2H3O2F(000) = 928
Mr = 211.30Dx = 1.215 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 1706 reflections
a = 25.7625 (12) Åθ = 3.0–25.1°
b = 6.4852 (3) ŵ = 0.08 mm1
c = 17.3970 (9) ÅT = 296 K
β = 127.377 (2)°Needle, colourless
V = 2309.8 (2) Å30.40 × 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 tubeRint = 0.077
Graphite monochromatorθmax = 26.0°, θmin = 2.0°
ϕ and ω scansh = 3131
15067 measured reflectionsk = 88
2261 independent reflectionsl = 2120
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.134H atoms treated by a mixture of independent and constrained refinement
S = 1.01 w = 1/[σ2(Fo2) + (0.0546P)2 + 1.9569P]
where P = (Fo2 + 2Fc2)/3
2261 reflections(Δ/σ)max < 0.001
149 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C10H18N+·C2H3O2V = 2309.8 (2) Å3
Mr = 211.30Z = 8
Monoclinic, C2/cMo Kα radiation
a = 25.7625 (12) ŵ = 0.08 mm1
b = 6.4852 (3) ÅT = 296 K
c = 17.3970 (9) Å0.40 × 0.07 × 0.05 mm
β = 127.377 (2)°
Data collection top
Bruker APEXII CCD
diffractometer
1471 reflections with I > 2σ(I)
15067 measured reflectionsRint = 0.077
2261 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.134H atoms treated by a mixture of independent and constrained refinement
S = 1.01Δρmax = 0.23 e Å3
2261 reflectionsΔρmin = 0.21 e Å3
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
xyzUiso*/Ueq
O10.32323 (7)0.4743 (2)0.78287 (11)0.0299 (4)
N10.19171 (10)0.5670 (3)0.68283 (14)0.0240 (5)
C10.16138 (10)0.5443 (3)0.57747 (15)0.0218 (5)
O20.36698 (8)0.7678 (2)0.78092 (12)0.0347 (4)
C20.17908 (11)0.3319 (3)0.56130 (15)0.0252 (5)
H2B0.22710.31840.60070.030*
H2A0.16280.22290.58150.030*
C30.14826 (10)0.3069 (3)0.45404 (15)0.0264 (5)
H3A0.15950.16790.44300.032*
C40.07403 (11)0.3266 (4)0.39419 (17)0.0327 (6)
H4A0.05700.21840.41370.039*
H4B0.05370.30750.32480.039*
C50.05648 (11)0.5400 (4)0.41012 (17)0.0299 (6)
H5A0.00790.55340.37050.036*
C60.08313 (11)0.7061 (4)0.38012 (17)0.0315 (6)
H6A0.07150.84430.38960.038*
H6B0.06330.69030.31070.038*
C70.15743 (11)0.6867 (3)0.44084 (16)0.0270 (5)
H7A0.17460.79620.42130.032*
C80.18804 (10)0.7119 (3)0.54849 (15)0.0243 (5)
H8A0.23620.70030.58810.029*
H8B0.17730.84960.55980.029*
C90.08731 (10)0.5654 (4)0.51785 (16)0.0267 (5)
H9A0.07610.70240.52910.032*
H9B0.07010.45850.53760.032*
C100.17474 (11)0.4742 (3)0.42404 (17)0.0287 (6)
H10A0.22270.46080.46260.034*
H10B0.15540.45780.35490.034*
C110.36787 (11)0.5780 (3)0.79083 (16)0.0251 (5)
C120.42684 (13)0.4608 (4)0.8153 (2)0.0465 (7)
H12A0.46380.48550.88320.070*
H12B0.43810.50790.77360.070*
H12C0.41690.31300.80520.070*
H1A0.2392 (15)0.544 (4)0.723 (2)0.055 (8)*
H1B0.1765 (12)0.461 (4)0.7010 (17)0.037 (7)*
H1C0.1835 (11)0.704 (3)0.6961 (17)0.043 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0225 (9)0.0286 (9)0.0383 (10)0.0000 (7)0.0183 (8)0.0033 (7)
N10.0244 (11)0.0242 (11)0.0265 (10)0.0001 (9)0.0170 (10)0.0004 (9)
C10.0183 (11)0.0227 (11)0.0218 (11)0.0014 (9)0.0109 (10)0.0002 (9)
O20.0440 (11)0.0258 (9)0.0491 (11)0.0017 (8)0.0360 (9)0.0018 (8)
C20.0240 (12)0.0228 (11)0.0282 (12)0.0003 (10)0.0155 (11)0.0017 (10)
C30.0261 (13)0.0210 (12)0.0313 (13)0.0004 (10)0.0170 (11)0.0029 (10)
C40.0267 (13)0.0352 (13)0.0307 (13)0.0096 (11)0.0145 (11)0.0073 (11)
C50.0171 (12)0.0380 (14)0.0286 (12)0.0004 (10)0.0108 (10)0.0007 (11)
C60.0287 (14)0.0342 (14)0.0277 (12)0.0070 (11)0.0151 (11)0.0067 (11)
C70.0289 (13)0.0265 (12)0.0307 (13)0.0009 (10)0.0208 (11)0.0036 (10)
C80.0228 (12)0.0206 (11)0.0312 (12)0.0017 (9)0.0173 (11)0.0015 (9)
C90.0218 (12)0.0295 (13)0.0326 (13)0.0001 (10)0.0185 (11)0.0009 (10)
C100.0260 (13)0.0354 (14)0.0269 (12)0.0003 (10)0.0171 (11)0.0038 (10)
C110.0258 (13)0.0276 (12)0.0255 (12)0.0022 (10)0.0174 (11)0.0001 (10)
C120.0401 (16)0.0417 (16)0.072 (2)0.0117 (13)0.0416 (16)0.0143 (14)
Geometric parameters (Å, º) top
O1—C111.265 (3)C5—C91.537 (3)
N1—C11.501 (3)C5—H5A1.0000
N1—H1A0.98 (3)C6—C71.530 (3)
N1—H1B0.94 (3)C6—H6A0.9900
N1—H1C0.976 (17)C6—H6B0.9900
C1—C81.526 (3)C7—C101.530 (3)
C1—C91.527 (3)C7—C81.537 (3)
C1—C21.530 (3)C7—H7A1.0000
O2—C111.241 (3)C8—H8A0.9900
C2—C31.530 (3)C8—H8B0.9900
C2—H2B0.9900C9—H9A0.9900
C2—H2A0.9900C9—H9B0.9900
C3—C41.530 (3)C10—H10A0.9900
C3—C101.532 (3)C10—H10B0.9900
C3—H3A1.0000C11—C121.510 (3)
C4—C51.533 (3)C12—H12A0.9800
C4—H4A0.9900C12—H12B0.9800
C4—H4B0.9900C12—H12C0.9800
C5—C61.529 (3)
C1—N1—H1A110.6 (16)C7—C6—H6A109.7
C1—N1—H1B109.1 (15)C5—C6—H6B109.7
H1A—N1—H1B104 (2)C7—C6—H6B109.7
C1—N1—H1C110.6 (14)H6A—C6—H6B108.2
H1A—N1—H1C109 (2)C6—C7—C10109.25 (18)
H1B—N1—H1C113 (2)C6—C7—C8109.50 (18)
N1—C1—C8109.19 (17)C10—C7—C8109.58 (18)
N1—C1—C9109.28 (17)C6—C7—H7A109.5
C8—C1—C9109.84 (17)C10—C7—H7A109.5
N1—C1—C2108.69 (17)C8—C7—H7A109.5
C8—C1—C2109.66 (17)C1—C8—C7109.02 (17)
C9—C1—C2110.15 (17)C1—C8—H8A109.9
C3—C2—C1109.15 (17)C7—C8—H8A109.9
C3—C2—H2B109.9C1—C8—H8B109.9
C1—C2—H2B109.9C7—C8—H8B109.9
C3—C2—H2A109.9H8A—C8—H8B108.3
C1—C2—H2A109.9C1—C9—C5109.05 (18)
H2B—C2—H2A108.3C1—C9—H9A109.9
C2—C3—C4109.27 (19)C5—C9—H9A109.9
C2—C3—C10109.36 (18)C1—C9—H9B109.9
C4—C3—C10109.87 (19)C5—C9—H9B109.9
C2—C3—H3A109.4H9A—C9—H9B108.3
C4—C3—H3A109.4C7—C10—C3109.35 (18)
C10—C3—H3A109.4C7—C10—H10A109.8
C3—C4—C5109.68 (18)C3—C10—H10A109.8
C3—C4—H4A109.7C7—C10—H10B109.8
C5—C4—H4A109.7C3—C10—H10B109.8
C3—C4—H4B109.7H10A—C10—H10B108.3
C5—C4—H4B109.7O2—C11—O1125.0 (2)
H4A—C4—H4B108.2O2—C11—C12118.0 (2)
C6—C5—C4109.34 (19)O1—C11—C12117.1 (2)
C6—C5—C9109.52 (18)C11—C12—H12A109.5
C4—C5—C9109.03 (18)C11—C12—H12B109.5
C6—C5—H5A109.6H12A—C12—H12B109.5
C4—C5—H5A109.6C11—C12—H12C109.5
C9—C5—H5A109.6H12A—C12—H12C109.5
C5—C6—C7109.83 (18)H12B—C12—H12C109.5
C5—C6—H6A109.7
N1—C1—C2—C3179.86 (18)C9—C1—C8—C760.8 (2)
C8—C1—C2—C360.8 (2)C2—C1—C8—C760.4 (2)
C9—C1—C2—C360.2 (2)C6—C7—C8—C159.8 (2)
C1—C2—C3—C459.9 (2)C10—C7—C8—C160.0 (2)
C1—C2—C3—C1060.4 (2)N1—C1—C9—C5179.49 (17)
C2—C3—C4—C560.6 (2)C8—C1—C9—C560.7 (2)
C10—C3—C4—C559.4 (2)C2—C1—C9—C560.1 (2)
C3—C4—C5—C659.2 (2)C6—C5—C9—C159.7 (2)
C3—C4—C5—C960.5 (2)C4—C5—C9—C159.9 (2)
C4—C5—C6—C759.9 (2)C6—C7—C10—C360.0 (2)
C9—C5—C6—C759.5 (2)C8—C7—C10—C359.9 (2)
C5—C6—C7—C1060.5 (2)C2—C3—C10—C760.2 (2)
C5—C6—C7—C859.5 (2)C4—C3—C10—C759.8 (2)
N1—C1—C8—C7179.39 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O10.99 (4)1.80 (4)2.777 (3)171 (3)
N1—H1B···O2i0.94 (3)1.83 (3)2.758 (3)170 (3)
N1—H1C···O1ii0.97 (2)1.82 (2)2.786 (2)171 (3)
Symmetry codes: (i) x+1/2, y1/2, z+3/2; (ii) x+1/2, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC10H18N+·C2H3O2
Mr211.30
Crystal system, space groupMonoclinic, C2/c
Temperature (K)296
a, b, c (Å)25.7625 (12), 6.4852 (3), 17.3970 (9)
β (°) 127.377 (2)
V3)2309.8 (2)
Z8
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.40 × 0.07 × 0.05
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
15067, 2261, 1471
Rint0.077
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.134, 1.01
No. of reflections2261
No. of parameters149
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)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···AD—HH···AD···AD—H···A
N1—H1A···O10.99 (4)1.80 (4)2.777 (3)171 (3)
N1—H1B···O2i0.94 (3)1.83 (3)2.758 (3)170 (3)
N1—H1C···O1ii0.97 (2)1.82 (2)2.786 (2)171 (3)
Symmetry codes: (i) x+1/2, y1/2, 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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