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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1415.
Published online 2009 May 29. doi:  10.1107/S1600536809019424
PMCID: PMC2969728

Hexane-1,6-diammonium bis­(pyridine-2-carboxyl­ate)

Abstract

The title compound, C6H18N2 2+·2C6H4NO2 , consists of a doubly protonated hexa­methyl­enediammonium dication and two pyridine-2-carboxyl­ate anions. These ions inter­act by means of inter­molecular N—H(...)O and N—H(...)N hydrogen bonds to form a two-dimensional array. The carboxyl­ate groups of the anions appear to be delocalized on the basis of the C—O bond lengths.

Related literature

For the crystal structures of (C6H18N2)X 2 (X = Cl, Br or I), see: Binnie & Robertson (1949a [triangle],b [triangle]); Borkakoti et al. (1978 [triangle]); van Blerk & Kruger (2008 [triangle]). For details of some other hexane-1,6-diammonium compounds, see: Phan Thanh et al. (2000 [triangle]); Mousdis et al. (2000 [triangle]); Rakovský et al. (2002 [triangle]); Dammak et al. (2007 [triangle]); Sun et al. (2007 [triangle]); Yang et al. (2007 [triangle]); Wilkinson & Harrison (2007 [triangle]); Wang & Wei (2007 [triangle]). For the structure of pyridine-2-carboxylic acid, see: Hamazaki et al. (1998 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1415-scheme1.jpg

Experimental

Crystal data

  • C6H18N2 2+·2C6H4NO2
  • M r = 362.43
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1415-efi1.jpg
  • a = 9.8182 (7) Å
  • b = 9.1569 (7) Å
  • c = 21.6423 (17) Å
  • β = 99.038 (2)°
  • V = 1921.6 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 296 K
  • 0.33 × 0.25 × 0.18 mm

Data collection

  • Bruker SMART 1000 CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2000 [triangle]) T min = 0.685, T max = 0.984
  • 13964 measured reflections
  • 4752 independent reflections
  • 1740 reflections with I > 2σ(I)
  • R int = 0.089

Refinement

  • R[F 2 > 2σ(F 2)] = 0.057
  • wR(F 2) = 0.124
  • S = 0.93
  • 4752 reflections
  • 339 parameters
  • All H-atom parameters refined
  • Δρmax = 0.15 e Å−3
  • Δρmin = −0.15 e Å−3

Data collection: SMART (Bruker, 2000 [triangle]); cell refinement: SAINT (Bruker, 2000 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809019424/tk2459sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809019424/tk2459Isup2.hkl

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

Acknowledgments

This work was supported by the Korea Research Foundation Grant funded by the Korean Government (MOEHRD) (grant No. KRF-2007–412-J02001).

supplementary crystallographic information

Comment

The title compound, C6H18N22+.2C6H4NO2-, consists of a doubly protonated hexamethylenediammonium dication and two pyridinecarboxylate anions (Fig. 1). The carboxylate groups of the anions appear to be delocalized on the basis of the C—O bond lengths (C—O: 1.241 (3)–1.247 (3) Å). The N3—C13—C14—C15 and C16—C17—C18—N4 torsion angles [64.9 (4)° and -66.6 (4)°, respectively] display the gauche conformation for the two groups within the dication, whereas C13—C14—C15—C16, C14—C15—C16—C17 and C15—C16—C17—C18 atoms show the anti conformation [their torsion angles lie in the range of 174.6 (3)°–177.3 (3)°]. In the crystal, the component ions interact by means of many intermolecular N—H···O and N—H···N hydrogen bonds and C—H···O contacts to form a 2-D array (Table 1 and Fig. 2).

Experimental

A solution of 1,6-diaminohexane (0.200 g, 1.721 mmol) and pyridine-2-carboxylic acid (1.180 g, 8.606 mmol) in H2O (20 ml) was stirred for 2 h at 333 K. The solvent was removed under vacuum and the residue was washed with acetone to give a white powder (0.5972 g). Crystals were obtained by slow evaporation from an ethanol solution.

Refinement

All H atoms were located from Fourier difference maps and refined isotropically; C—H = 0.96 (3)–1.13 (3) Å and N—H = 0.92 (3)–1.07 (3) Å.

Figures

Fig. 1.
The molecular structures of the components (I), with displacement ellipsoids drawn at the 30% probability level for non-H atoms.
Fig. 2.
View of the unit-cell contents for (I). Hydrogen-bond interactions are drawn with dashed lines.

Crystal data

C6H18N22+·2C6H4NO2F(000) = 776
Mr = 362.43Dx = 1.253 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1472 reflections
a = 9.8182 (7) Åθ = 2.6–24.0°
b = 9.1569 (7) ŵ = 0.09 mm1
c = 21.6423 (17) ÅT = 296 K
β = 99.038 (2)°Block, colourless
V = 1921.6 (3) Å30.33 × 0.25 × 0.18 mm
Z = 4

Data collection

Bruker SMART 1000 CCD diffractometer4752 independent reflections
Radiation source: fine-focus sealed tube1740 reflections with I > 2σ(I)
graphiteRint = 0.089
[var phi] and ω scansθmax = 28.3°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2000)h = −13→13
Tmin = 0.685, Tmax = 0.984k = −12→12
13964 measured reflectionsl = −21→28

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.057Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.124All H-atom parameters refined
S = 0.93w = 1/[σ2(Fo2) + (0.0318P)2] where P = (Fo2 + 2Fc2)/3
4752 reflections(Δ/σ)max < 0.001
339 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = −0.15 e Å3

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 (Å2)

xyzUiso*/Ueq
O10.39197 (19)0.3983 (2)0.43294 (9)0.0607 (6)
O20.3440 (2)0.1705 (2)0.40142 (11)0.0809 (7)
N10.5671 (2)0.4287 (2)0.34905 (10)0.0514 (6)
C10.6534 (3)0.4405 (4)0.30699 (15)0.0632 (9)
H10.704 (3)0.538 (3)0.3085 (12)0.078 (10)*
C20.6711 (3)0.3335 (4)0.26461 (16)0.0684 (9)
H20.739 (3)0.351 (3)0.2336 (14)0.100 (11)*
C30.5975 (4)0.2072 (4)0.26545 (16)0.0702 (10)
H30.605 (3)0.128 (3)0.2356 (13)0.080 (10)*
C40.5110 (3)0.1905 (3)0.30952 (14)0.0586 (8)
H40.458 (2)0.099 (3)0.3141 (12)0.061 (8)*
C50.4980 (3)0.3030 (3)0.35030 (12)0.0428 (6)
C60.4034 (3)0.2901 (3)0.39927 (14)0.0508 (7)
O30.1328 (2)0.4425 (2)0.07130 (9)0.0654 (6)
O40.2162 (2)0.2478 (2)0.12601 (10)0.0760 (7)
N20.0026 (2)0.5187 (3)0.16852 (11)0.0617 (7)
C7−0.0394 (4)0.5760 (4)0.21915 (18)0.0749 (10)
H7−0.127 (3)0.630 (3)0.2088 (13)0.084 (10)*
C80.0265 (4)0.5565 (4)0.27899 (17)0.0718 (10)
H8−0.010 (3)0.603 (3)0.3131 (14)0.080 (10)*
C90.1416 (4)0.4708 (4)0.28807 (15)0.0653 (9)
H90.195 (3)0.456 (3)0.3287 (12)0.066 (9)*
C100.1851 (3)0.4064 (3)0.23713 (14)0.0545 (8)
H100.268 (3)0.344 (3)0.2409 (13)0.083 (10)*
C110.1141 (3)0.4333 (3)0.17813 (13)0.0443 (7)
C120.1582 (3)0.3693 (3)0.12002 (14)0.0479 (7)
N30.4265 (3)0.1748 (3)0.06174 (13)0.0505 (7)
H3A0.334 (3)0.200 (3)0.0800 (14)0.114 (12)*
H3B0.467 (3)0.090 (3)0.0830 (15)0.095 (12)*
H3C0.415 (3)0.154 (3)0.0194 (16)0.092 (12)*
N41.1032 (3)0.3355 (3)−0.04832 (13)0.0487 (6)
H4A1.046 (3)0.403 (3)−0.0754 (12)0.068 (10)*
H4B1.117 (3)0.372 (3)−0.0007 (16)0.099 (11)*
H4C1.196 (4)0.333 (3)−0.0672 (15)0.126 (13)*
C130.5150 (3)0.3063 (4)0.07920 (18)0.0655 (9)
H13A0.500 (3)0.334 (3)0.1259 (15)0.101 (11)*
H13B0.475 (3)0.388 (3)0.0459 (14)0.099 (11)*
C140.6652 (4)0.2789 (4)0.07806 (17)0.0676 (10)
H14A0.718 (3)0.372 (3)0.0970 (13)0.086 (10)*
H14B0.697 (3)0.194 (3)0.1038 (14)0.090 (12)*
C150.6995 (3)0.2449 (4)0.01361 (16)0.0600 (9)
H15A0.654 (3)0.150 (3)−0.0029 (13)0.073 (9)*
H15B0.654 (3)0.336 (3)−0.0184 (14)0.100 (11)*
C160.8544 (3)0.2304 (4)0.01326 (16)0.0578 (8)
H16A0.895 (3)0.153 (3)0.0455 (12)0.072 (9)*
H16B0.898 (2)0.328 (3)0.0250 (12)0.070 (9)*
C170.8877 (3)0.1893 (4)−0.05053 (16)0.0623 (9)
H17A0.841 (3)0.261 (3)−0.0839 (13)0.075 (10)*
H17B0.851 (3)0.083 (3)−0.0641 (14)0.103 (11)*
C181.0393 (4)0.1871 (4)−0.05523 (19)0.0660 (9)
H18A1.054 (3)0.150 (3)−0.1001 (15)0.110 (12)*
H18B1.088 (3)0.123 (3)−0.0212 (15)0.102 (13)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0655 (13)0.0674 (13)0.0506 (12)0.0062 (11)0.0135 (11)−0.0096 (11)
O20.0771 (15)0.0718 (15)0.1046 (19)−0.0218 (12)0.0482 (14)−0.0166 (14)
N10.0577 (15)0.0545 (15)0.0435 (14)−0.0030 (12)0.0132 (12)−0.0014 (12)
C10.077 (2)0.062 (2)0.053 (2)−0.0093 (19)0.0165 (19)−0.0003 (19)
C20.069 (2)0.079 (3)0.062 (2)−0.006 (2)0.0240 (19)−0.007 (2)
C30.083 (2)0.071 (2)0.061 (2)0.008 (2)0.026 (2)−0.019 (2)
C40.065 (2)0.0547 (19)0.058 (2)−0.0009 (17)0.0143 (17)−0.0086 (18)
C50.0387 (15)0.0484 (16)0.0397 (16)0.0027 (14)0.0009 (13)0.0009 (15)
C60.0406 (17)0.0568 (19)0.0536 (19)0.0032 (16)0.0037 (15)−0.0004 (17)
O30.0893 (16)0.0646 (13)0.0413 (12)0.0046 (11)0.0075 (11)0.0000 (12)
O40.0864 (16)0.0717 (14)0.0775 (16)0.0331 (13)0.0361 (13)0.0103 (13)
N20.0638 (17)0.0723 (17)0.0496 (16)0.0235 (14)0.0108 (14)0.0054 (14)
C70.076 (3)0.083 (3)0.066 (2)0.031 (2)0.014 (2)0.005 (2)
C80.088 (3)0.073 (2)0.060 (2)0.010 (2)0.029 (2)−0.002 (2)
C90.077 (3)0.077 (2)0.041 (2)−0.001 (2)0.0073 (19)0.007 (2)
C100.0522 (19)0.062 (2)0.0489 (19)0.0088 (16)0.0048 (17)0.0112 (18)
C110.0437 (17)0.0441 (16)0.0447 (17)0.0016 (14)0.0055 (14)0.0061 (15)
C120.0424 (17)0.0504 (18)0.0510 (19)−0.0023 (14)0.0073 (15)0.0037 (16)
N30.0516 (16)0.0521 (16)0.0487 (17)0.0030 (14)0.0111 (14)0.0051 (15)
N40.0480 (15)0.0531 (16)0.0445 (15)0.0048 (13)0.0060 (14)0.0050 (14)
C130.066 (2)0.055 (2)0.079 (3)−0.0051 (18)0.021 (2)−0.008 (2)
C140.063 (2)0.070 (2)0.072 (3)−0.010 (2)0.016 (2)−0.013 (2)
C150.052 (2)0.066 (2)0.063 (2)−0.0077 (18)0.0128 (18)0.000 (2)
C160.052 (2)0.058 (2)0.064 (2)−0.0051 (17)0.0086 (17)0.0004 (19)
C170.059 (2)0.069 (2)0.061 (2)−0.0086 (19)0.0140 (18)−0.008 (2)
C180.069 (2)0.060 (2)0.074 (3)−0.0004 (19)0.025 (2)−0.010 (2)

Geometric parameters (Å, °)

O1—C61.245 (3)N3—C131.498 (4)
O2—C61.245 (3)N3—H3A1.07 (3)
N1—C51.339 (3)N3—H3B0.96 (3)
N1—C11.341 (3)N3—H3C0.92 (3)
C1—C21.371 (4)N4—C181.495 (4)
C1—H11.02 (3)N4—H4A0.97 (3)
C2—C31.365 (4)N4—H4B1.07 (3)
C2—H21.03 (3)N4—H4C1.05 (3)
C3—C41.381 (4)C13—C141.500 (4)
C3—H30.98 (3)C13—H13A1.08 (3)
C4—C51.375 (3)C13—H13B1.07 (3)
C4—H41.00 (2)C14—C151.518 (4)
C5—C61.520 (3)C14—H14A1.05 (3)
O3—C121.241 (3)C14—H14B0.98 (3)
O4—C121.247 (3)C15—C161.528 (4)
N2—C111.335 (3)C15—H15A1.01 (3)
N2—C71.337 (4)C15—H15B1.13 (3)
C7—C81.365 (4)C16—C171.515 (4)
C7—H70.99 (3)C16—H16A1.03 (3)
C8—C91.365 (4)C16—H16B1.01 (3)
C8—H80.97 (3)C17—C181.508 (4)
C9—C101.376 (4)C17—H17A1.03 (3)
C9—H90.96 (3)C17—H17B1.06 (3)
C10—C111.378 (4)C18—H18A1.06 (3)
C10—H100.99 (3)C18—H18B1.01 (3)
C11—C121.512 (4)
C5—N1—C1117.3 (3)H3B—N3—H3C107 (3)
N1—C1—C2123.8 (3)C18—N4—H4A108.7 (15)
N1—C1—H1114.0 (15)C18—N4—H4B111.5 (16)
C2—C1—H1122.2 (15)H4A—N4—H4B111 (2)
C3—C2—C1118.2 (3)C18—N4—H4C108.3 (18)
C3—C2—H2122.6 (17)H4A—N4—H4C104 (2)
C1—C2—H2119.1 (17)H4B—N4—H4C113 (2)
C2—C3—C4119.1 (3)N3—C13—C14113.3 (3)
C2—C3—H3121.3 (16)N3—C13—H13A105.3 (16)
C4—C3—H3119.6 (16)C14—C13—H13A109.7 (16)
C5—C4—C3119.3 (3)N3—C13—H13B104.9 (16)
C5—C4—H4117.4 (15)C14—C13—H13B111.3 (16)
C3—C4—H4123.3 (15)H13A—C13—H13B112 (2)
N1—C5—C4122.2 (3)C13—C14—C15114.2 (3)
N1—C5—C6116.6 (2)C13—C14—H14A106.5 (15)
C4—C5—C6121.2 (3)C15—C14—H14A111.1 (15)
O2—C6—O1126.3 (3)C13—C14—H14B110.6 (18)
O2—C6—C5115.8 (3)C15—C14—H14B105.3 (18)
O1—C6—C5117.9 (3)H14A—C14—H14B109 (2)
C11—N2—C7116.9 (3)C14—C15—C16112.8 (3)
N2—C7—C8124.4 (3)C14—C15—H15A110.5 (15)
N2—C7—H7112.3 (17)C16—C15—H15A108.0 (15)
C8—C7—H7123.2 (17)C14—C15—H15B106.8 (15)
C9—C8—C7118.0 (3)C16—C15—H15B111.0 (14)
C9—C8—H8122.6 (17)H15A—C15—H15B108 (2)
C7—C8—H8119.4 (17)C17—C16—C15112.5 (3)
C8—C9—C10119.0 (3)C17—C16—H16A109.2 (14)
C8—C9—H9122.0 (16)C15—C16—H16A109.9 (14)
C10—C9—H9118.9 (16)C17—C16—H16B107.8 (15)
C9—C10—C11119.4 (3)C15—C16—H16B107.9 (14)
C9—C10—H10122.4 (17)H16A—C16—H16B110 (2)
C11—C10—H10118.2 (17)C18—C17—C16114.9 (3)
N2—C11—C10122.2 (3)C18—C17—H17A107.2 (15)
N2—C11—C12115.7 (3)C16—C17—H17A110.3 (15)
C10—C11—C12122.2 (3)C18—C17—H17B105.3 (16)
O3—C12—O4126.7 (3)C16—C17—H17B111.6 (16)
O3—C12—C11116.8 (3)H17A—C17—H17B107 (2)
O4—C12—C11116.5 (3)N4—C18—C17112.6 (3)
C13—N3—H3A103.1 (16)N4—C18—H18A105.7 (17)
C13—N3—H3B110.6 (18)C17—C18—H18A110.1 (17)
H3A—N3—H3B108 (2)N4—C18—H18B108.5 (18)
C13—N3—H3C113.2 (19)C17—C18—H18B108.7 (18)
H3A—N3—H3C115 (3)H18A—C18—H18B111 (2)
C5—N1—C1—C22.0 (4)C8—C9—C10—C111.9 (5)
N1—C1—C2—C3−0.5 (5)C7—N2—C11—C10−1.1 (4)
C1—C2—C3—C4−1.4 (5)C7—N2—C11—C12179.5 (3)
C2—C3—C4—C51.8 (5)C9—C10—C11—N2−0.9 (4)
C1—N1—C5—C4−1.5 (4)C9—C10—C11—C12178.5 (3)
C1—N1—C5—C6178.6 (2)N2—C11—C12—O330.2 (3)
C3—C4—C5—N1−0.3 (4)C10—C11—C12—O3−149.2 (3)
C3—C4—C5—C6179.6 (3)N2—C11—C12—O4−149.6 (2)
N1—C5—C6—O2−177.3 (3)C10—C11—C12—O431.0 (4)
C4—C5—C6—O22.8 (4)N3—C13—C14—C1564.9 (4)
N1—C5—C6—O12.9 (4)C13—C14—C15—C16175.1 (3)
C4—C5—C6—O1−177.0 (3)C14—C15—C16—C17177.3 (3)
C11—N2—C7—C82.2 (5)C15—C16—C17—C18174.6 (3)
N2—C7—C8—C9−1.2 (6)C16—C17—C18—N4−66.6 (4)
C7—C8—C9—C10−0.9 (5)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N3—H3A···O41.07 (3)1.70 (3)2.747 (3)165 (3)
N3—H3B···O1i0.96 (3)2.29 (3)3.088 (3)140 (2)
N3—H3B···N1i0.96 (3)2.15 (3)2.962 (3)142 (2)
N3—H3C···O1ii0.92 (3)1.91 (3)2.835 (3)177 (3)
N4—H4A···O3iii0.97 (3)2.27 (3)3.064 (3)139 (2)
N4—H4A···N2iii0.97 (3)2.12 (3)2.963 (3)144 (2)
N4—H4B···O3iv1.07 (3)1.67 (3)2.740 (3)175 (3)
N4—H4C···O2v1.05 (3)1.70 (4)2.754 (3)179 (3)
C1—H1···O4vi1.02 (3)2.45 (3)3.328 (4)145 (2)
C16—H16B···O3iv1.01 (3)2.58 (3)3.426 (4)140.8 (18)

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK2459).

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