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ISSN: 2056-9890

4-Amino­pyridinium cis-2-carb­­oxy­cyclo­hexane-1-carboxyl­ate

aFaculty of Science and Technology, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia
*Correspondence e-mail: g.smith@qut.edu.au

(Received 19 September 2011; accepted 26 September 2011; online 30 September 2011)

In the structure of the title molecular salt, C5H7N2+·C8H11O4, the cis monoanions associate through short O—H⋯O hydrogen bonds in the carb­oxy­lic acid groups [graph set C(7)], forming zigzag chains which extend along the c axis. These are inter­linked through pyridinium and amine N—H⋯O hydrogen bonds, giving a three-dimensional network structure.

Related literature

For the structure of racemic cis-cyclo­hexane-1,2-dicarb­oxy­lic acid, see: Benedetti et al. (1970[Benedetti, E., Pedone, C. & Allegra, G. (1970). J. Phys. Chem. 74, 512-516.]). For the structure of the racemic ammonium and 2-amino­pyridinium salts of cis-2-carb­oxy­cyclo­hexane-1-carboxyl­ate, see: Smith & Wermuth (2011a[Smith, G. & Wermuth, U. D. (2011a). Acta Cryst. E67, o174.],b[Smith, G. & Wermuth, U. D. (2011b). Acta Cryst. E67, o1900.]). For graph-set analysis, see Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]).

[Scheme 1]

Experimental

Crystal data
  • C5H7N2+·C8H11O4

  • Mr = 266.29

  • Orthorhombic, P n a 21

  • a = 12.1359 (3) Å

  • b = 9.8351 (3) Å

  • c = 11.1850 (3) Å

  • V = 1335.02 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 200 K

  • 0.30 × 0.25 × 0.20 mm

Data collection
  • Oxford Diffraction Gemini-S CCD-detector diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.948, Tmax = 0.990

  • 9670 measured reflections

  • 1709 independent reflections

  • 1448 reflections with I > 2σ(I)

  • Rint = 0.029

Refinement
  • R[F2 > 2σ(F2)] = 0.028

  • wR(F2) = 0.060

  • S = 0.99

  • 1709 reflections

  • 188 parameters

  • 1 restraint

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

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.16 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1A—H1A⋯O12i 0.88 (2) 1.91 (2) 2.795 (2) 180 (3)
N41A—H41A⋯O12ii 0.86 (2) 2.14 (2) 2.989 (2) 168 (2)
N41A—H42A⋯O22 0.91 (2) 2.13 (2) 2.974 (2) 152.6 (18)
O21—H21⋯O11iii 0.95 (3) 1.59 (3) 2.5302 (17) 170 (3)
Symmetry codes: (i) x, y, z+1; (ii) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) [-x, -y+1, z+{\script{1\over 2}}].

Data collection: CrysAlis PRO (Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) within WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: PLATON.

Supporting information


Comment top

The structures of Lewis base salts of cis-cyclohexane-1,2-dicarboxylic acid (cis-CHDC) are rare in the crystallographic literature and like the parent cis-acid (Benedetti et al., 1970), exist only in the unresolved racemic form. We have reported the structures of the 1:1 ammonium salt (Smith & Wermuth, 2011a) and the 1:1 2-aminopyridinium salt (Smith & Wermuth, 2011b) and in our parallel 1:1 stoichiometric reaction of cis-CHDC anhydride with 4-aminopyridine in 50% ethanol–water solution we also obtained minor crystals of the title compound, cis-C5H7N2+ C8H11O4- (Fig. 1) and the structure is reported here.

In the structure of the title compound, the monoanions associate through strong carboxylic acid–carboxyl O—H···O hydrogen bonds (Table 1) giving zigzag chains [graph set C(7) (Etter et al., 1990)] which extend along c (Fig. 2). The cations provide links between these chains through both pyridinium and amine NH···Ocarboxyl hydrogen bonds, resulting in a three-dimensional structure (Figs. 2,3).

Related literature top

For the structure of racemic cis-cyclohexane-1,2-dicarboxylic acid, see: Benedetti et al. (1970). For the structure of the racemic ammonium and 2-aminopyridinium salts of cis-2-carboxycyclohexane-1-carboxylate, see: Smith & Wermuth (2011a,b). For graph-set analysis, see Etter et al. (1990).

Experimental top

The title compound was synthesized by heating a solution of 1 mmol of cyclohexane-1,2-dicarboxylic anhydride and 1 mmol of 4-aminopyridine in 50 ml of 1:1 ethanol–water under reflux for 10 min. After concentration to 30 ml the solution was allowed to evaporate at room temperature, giving finally a residual viscous oil in which minor well formed colourless crystals of the title compound were found.

Refinement top

Hydrogen atoms involved in hydrogen-bonding interactions were located by difference methods and their positional and isotropic displacement parameters were refined. Other H-atoms were included in the refinement at calculated positions [C–H = 0.93–0.98 Å] and with Uiso(H) = 1.2Ueq(C), using a riding-model approximation. In the absence of a suitable heavy atom in the structure, the Friedel pairs (1332) were merged for the final cycles of the refinement. In the structure reported here, the cis-CHDC anion has the (1S,2R) configuration.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Molecular configuration and atom naming scheme for the cation the anion species in the title salt. Inter-species hydrogen bonds are shown as dashed lines and displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A perspective view of the unit cell showing the hydrogen-bonded zigzag C(7) cis-CHDC monoanion chains and their inter-linking cations, with hydrogen bonds shown as dashed lines. Non-associative H atoms are omitted. For symmetry codes, see Table 1.
[Figure 3] Fig. 3. A view of the hydrogen-bonded structure looking down the c axis.
4-Aminopyridinium cis-2-carboxycyclohexane-1-carboxylate top
Crystal data top
C5H7N2+·C8H11O4F(000) = 568
Mr = 266.29Dx = 1.325 Mg m3
Orthorhombic, Pna21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2nCell parameters from 4840 reflections
a = 12.1359 (3) Åθ = 3.2–28.7°
b = 9.8351 (3) ŵ = 0.10 mm1
c = 11.1850 (3) ÅT = 200 K
V = 1335.02 (6) Å3Block, colourless
Z = 40.30 × 0.25 × 0.20 mm
Data collection top
Oxford Diffraction Gemini-S CCD-detector
diffractometer
1709 independent reflections
Radiation source: Enhance (Mo) X-ray source1448 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
Detector resolution: 16.077 pixels mm-1θmax = 28.8°, θmin = 3.2°
ω scansh = 1615
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2010)
k = 1213
Tmin = 0.948, Tmax = 0.990l = 1315
9670 measured reflections
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)] = 0.028Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.060H atoms treated by a mixture of independent and constrained refinement
S = 0.99 w = 1/[σ2(Fo2) + (0.0357P)2]
where P = (Fo2 + 2Fc2)/3
1709 reflections(Δ/σ)max < 0.001
188 parametersΔρmax = 0.15 e Å3
1 restraintΔρmin = 0.16 e Å3
Crystal data top
C5H7N2+·C8H11O4V = 1335.02 (6) Å3
Mr = 266.29Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 12.1359 (3) ŵ = 0.10 mm1
b = 9.8351 (3) ÅT = 200 K
c = 11.1850 (3) Å0.30 × 0.25 × 0.20 mm
Data collection top
Oxford Diffraction Gemini-S CCD-detector
diffractometer
1709 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2010)
1448 reflections with I > 2σ(I)
Tmin = 0.948, Tmax = 0.990Rint = 0.029
9670 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0281 restraint
wR(F2) = 0.060H atoms treated by a mixture of independent and constrained refinement
S = 0.99Δρmax = 0.15 e Å3
1709 reflectionsΔρmin = 0.16 e Å3
188 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
O110.08623 (9)0.42384 (12)0.16082 (11)0.0293 (4)
O120.08627 (8)0.38250 (12)0.21757 (10)0.0262 (3)
O210.01171 (10)0.40723 (12)0.51058 (12)0.0285 (3)
O220.17703 (9)0.30714 (12)0.50187 (12)0.0296 (3)
C10.06239 (12)0.25883 (16)0.31330 (14)0.0202 (4)
C20.02258 (13)0.20096 (16)0.40246 (15)0.0223 (5)
C30.10393 (14)0.10098 (18)0.34520 (18)0.0311 (5)
C40.04378 (15)0.01169 (19)0.2767 (2)0.0410 (6)
C50.03704 (15)0.04676 (19)0.18597 (18)0.0340 (6)
C60.11879 (14)0.14099 (17)0.24603 (17)0.0272 (5)
C110.01574 (12)0.36284 (16)0.22481 (14)0.0200 (5)
C210.07930 (13)0.30994 (17)0.47466 (14)0.0222 (5)
N1A0.16603 (12)0.28917 (15)0.99803 (15)0.0301 (4)
N41A0.30073 (13)0.14997 (18)0.68510 (15)0.0320 (5)
C2A0.14635 (14)0.35553 (19)0.89470 (16)0.0306 (5)
C3A0.18908 (13)0.31222 (17)0.78984 (16)0.0285 (5)
C4A0.25659 (12)0.19462 (16)0.78670 (15)0.0236 (5)
C5A0.27516 (14)0.12848 (18)0.89698 (16)0.0289 (5)
C6A0.22940 (14)0.17671 (18)0.99826 (17)0.0309 (5)
H10.119400.305100.360200.0240*
H20.020100.147400.460100.0270*
H210.046 (2)0.473 (3)0.561 (3)0.069 (8)*
H31B0.152000.149900.290800.0370*
H32B0.149400.060500.407000.0370*
H41B0.097300.068000.235500.0490*
H42B0.004200.068800.332800.0490*
H51B0.003200.096400.125100.0410*
H52B0.076400.026900.147200.0410*
H61B0.163000.089100.302000.0330*
H62B0.167900.178300.186000.0330*
H1A0.1408 (18)0.319 (2)1.0674 (19)0.038 (6)*
H2A0.102300.432900.895600.0370*
H3A0.174200.359600.719700.0340*
H5A0.319200.051200.899700.0350*
H6A0.241900.131301.069900.0370*
H41A0.3409 (18)0.078 (2)0.687 (2)0.047 (6)*
H42A0.2841 (16)0.193 (2)0.615 (2)0.038 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O110.0297 (6)0.0270 (6)0.0312 (7)0.0010 (5)0.0051 (5)0.0106 (6)
O120.0244 (6)0.0291 (6)0.0251 (6)0.0047 (5)0.0004 (5)0.0028 (5)
O210.0321 (6)0.0263 (6)0.0272 (6)0.0042 (5)0.0021 (6)0.0066 (6)
O220.0304 (6)0.0316 (6)0.0269 (6)0.0036 (5)0.0062 (5)0.0019 (6)
C10.0205 (7)0.0188 (8)0.0212 (8)0.0009 (6)0.0009 (6)0.0003 (7)
C20.0267 (8)0.0193 (8)0.0209 (8)0.0009 (7)0.0007 (7)0.0046 (7)
C30.0325 (9)0.0253 (9)0.0354 (10)0.0084 (8)0.0064 (8)0.0016 (8)
C40.0439 (10)0.0247 (9)0.0543 (13)0.0080 (8)0.0046 (10)0.0118 (9)
C50.0387 (10)0.0270 (9)0.0363 (11)0.0064 (8)0.0040 (9)0.0106 (8)
C60.0269 (8)0.0226 (8)0.0322 (10)0.0068 (7)0.0053 (7)0.0039 (8)
C110.0254 (8)0.0166 (8)0.0179 (8)0.0006 (6)0.0006 (6)0.0031 (6)
C210.0287 (8)0.0222 (8)0.0157 (8)0.0017 (7)0.0004 (6)0.0051 (7)
N1A0.0318 (7)0.0344 (8)0.0240 (8)0.0016 (6)0.0021 (7)0.0067 (8)
N41A0.0366 (8)0.0293 (9)0.0302 (9)0.0098 (7)0.0024 (7)0.0044 (7)
C2A0.0324 (9)0.0258 (9)0.0335 (10)0.0077 (8)0.0012 (8)0.0007 (9)
C3A0.0334 (9)0.0241 (9)0.0281 (9)0.0057 (7)0.0019 (8)0.0023 (8)
C4A0.0225 (7)0.0209 (8)0.0275 (9)0.0010 (6)0.0021 (7)0.0032 (8)
C5A0.0305 (9)0.0233 (9)0.0329 (10)0.0054 (7)0.0085 (8)0.0012 (8)
C6A0.0334 (9)0.0328 (9)0.0264 (9)0.0001 (8)0.0080 (8)0.0013 (9)
Geometric parameters (Å, º) top
O11—C111.2665 (19)C1—H10.9800
O12—C111.2556 (18)C2—H20.9800
O21—C211.323 (2)C3—H32B0.9700
O22—C211.2248 (19)C3—H31B0.9700
O21—H210.95 (3)C4—H42B0.9700
N1A—C6A1.347 (2)C4—H41B0.9700
N1A—C2A1.349 (2)C5—H51B0.9700
N41A—C4A1.331 (2)C5—H52B0.9700
N1A—H1A0.88 (2)C6—H61B0.9700
N41A—H41A0.86 (2)C6—H62B0.9700
N41A—H42A0.91 (2)C2A—C3A1.351 (2)
C1—C21.543 (2)C3A—C4A1.418 (2)
C1—C111.532 (2)C4A—C5A1.413 (2)
C1—C61.542 (2)C5A—C6A1.348 (3)
C2—C31.534 (2)C2A—H2A0.9300
C2—C211.508 (2)C3A—H3A0.9300
C3—C41.532 (3)C5A—H5A0.9300
C4—C51.524 (3)C6A—H6A0.9300
C5—C61.515 (3)
C21—O21—H21113.6 (15)C2—C3—H31B109.00
C2A—N1A—C6A120.01 (16)C2—C3—H32B109.00
C6A—N1A—H1A117.9 (13)C5—C4—H41B109.00
C2A—N1A—H1A122.0 (13)C5—C4—H42B109.00
H41A—N41A—H42A122 (2)C3—C4—H42B109.00
C4A—N41A—H41A118.6 (15)C3—C4—H41B109.00
C4A—N41A—H42A119.4 (13)H41B—C4—H42B108.00
C2—C1—C6109.55 (13)C6—C5—H51B109.00
C2—C1—C11114.64 (12)C4—C5—H52B109.00
C6—C1—C11110.53 (13)C6—C5—H52B109.00
C1—C2—C21112.88 (13)H51B—C5—H52B108.00
C1—C2—C3113.38 (14)C4—C5—H51B109.00
C3—C2—C21112.67 (13)C5—C6—H62B109.00
C2—C3—C4111.46 (14)H61B—C6—H62B108.00
C3—C4—C5111.52 (15)C1—C6—H61B109.00
C4—C5—C6110.92 (16)C1—C6—H62B109.00
C1—C6—C5112.68 (14)C5—C6—H61B109.00
O11—C11—C1115.58 (13)N1A—C2A—C3A121.56 (17)
O11—C11—O12123.82 (14)C2A—C3A—C4A120.03 (16)
O12—C11—C1120.59 (13)N41A—C4A—C3A121.53 (16)
O21—C21—C2113.18 (13)C3A—C4A—C5A116.50 (15)
O22—C21—C2123.99 (15)N41A—C4A—C5A121.97 (15)
O21—C21—O22122.77 (15)C4A—C5A—C6A120.41 (16)
C6—C1—H1107.00N1A—C6A—C5A121.50 (17)
C2—C1—H1107.00N1A—C2A—H2A119.00
C11—C1—H1107.00C3A—C2A—H2A119.00
C1—C2—H2106.00C2A—C3A—H3A120.00
C3—C2—H2106.00C4A—C3A—H3A120.00
C21—C2—H2106.00C4A—C5A—H5A120.00
C4—C3—H32B109.00C6A—C5A—H5A120.00
H31B—C3—H32B108.00N1A—C6A—H6A119.00
C4—C3—H31B109.00C5A—C6A—H6A119.00
C6A—N1A—C2A—C3A0.2 (3)C3—C2—C21—O21171.15 (14)
C2A—N1A—C6A—C5A0.6 (3)C3—C2—C21—O2211.6 (2)
C6—C1—C2—C351.98 (17)C1—C2—C21—O2141.13 (19)
C11—C1—C2—C2156.73 (18)C1—C2—C21—O22141.58 (16)
C6—C1—C2—C21178.36 (13)C2—C3—C4—C553.7 (2)
C11—C1—C2—C372.93 (17)C3—C4—C5—C656.2 (2)
C2—C1—C11—O11171.66 (14)C4—C5—C6—C157.4 (2)
C2—C1—C11—O129.2 (2)N1A—C2A—C3A—C4A0.2 (3)
C6—C1—C11—O1163.95 (18)C2A—C3A—C4A—N41A179.40 (16)
C6—C1—C11—O12115.22 (16)C2A—C3A—C4A—C5A0.0 (2)
C11—C1—C6—C572.82 (18)N41A—C4A—C5A—C6A179.81 (17)
C2—C1—C6—C554.43 (19)C3A—C4A—C5A—C6A0.4 (2)
C21—C2—C3—C4177.72 (15)C4A—C5A—C6A—N1A0.7 (3)
C1—C2—C3—C452.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1A—H1A···O12i0.88 (2)1.91 (2)2.795 (2)180 (3)
N41A—H41A···O12ii0.86 (2)2.14 (2)2.989 (2)168 (2)
N41A—H42A···O220.91 (2)2.13 (2)2.974 (2)152.6 (18)
O21—H21···O11iii0.95 (3)1.59 (3)2.5302 (17)170 (3)
C2A—H2A···O21iii0.932.463.287 (2)149
C3A—H3A···O220.932.493.225 (2)136
C3A—H3A···O11iii0.932.473.222 (2)138
C6A—H6A···O11iv0.932.383.048 (2)128
C3—H31B···O120.972.563.123 (2)117
Symmetry codes: (i) x, y, z+1; (ii) x+1/2, y1/2, z+1/2; (iii) x, y+1, z+1/2; (iv) x+1/2, y+1/2, z+1.

Experimental details

Crystal data
Chemical formulaC5H7N2+·C8H11O4
Mr266.29
Crystal system, space groupOrthorhombic, Pna21
Temperature (K)200
a, b, c (Å)12.1359 (3), 9.8351 (3), 11.1850 (3)
V3)1335.02 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerOxford Diffraction Gemini-S CCD-detector
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2010)
Tmin, Tmax0.948, 0.990
No. of measured, independent and
observed [I > 2σ(I)] reflections
9670, 1709, 1448
Rint0.029
(sin θ/λ)max1)0.678
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.028, 0.060, 0.99
No. of reflections1709
No. of parameters188
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.15, 0.16

Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008) within WinGX (Farrugia, 1999), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1A—H1A···O12i0.88 (2)1.91 (2)2.795 (2)180 (3)
N41A—H41A···O12ii0.86 (2)2.14 (2)2.989 (2)168 (2)
N41A—H42A···O220.91 (2)2.13 (2)2.974 (2)152.6 (18)
O21—H21···O11iii0.95 (3)1.59 (3)2.5302 (17)170 (3)
Symmetry codes: (i) x, y, z+1; (ii) x+1/2, y1/2, z+1/2; (iii) x, y+1, z+1/2.
 

Acknowledgements

The authors acknowledge financial support from the Australian Research Council, the Faculty of Science and Technology and the University Library, Queensland University of Technology.

References

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