2-Amino-6-(quinoline-2-carboxamido)­pyridinium nitrate

Phillipus C W Van der Berg; Hendrik G Visser; Andreas Roodt

doi:10.1107/S1600536812036562

. 2012 Aug 31;68(Pt 9):o2808. doi: 10.1107/S1600536812036562

2-Amino-6-(quinoline-2-carboxamido)pyridinium nitrate

Phillipus C W Van der Berg ^a,^*, Hendrik G Visser ^a, Andreas Roodt ^a

PMCID: PMC3435834 PMID: 22969680

Abstract

In the title salt, C₁₅H₁₃N₄O⁺·NO₃ ⁻, an extensive network of N—H⋯N, N—H⋯O and C—H⋯O hydrogen-bond interactions are observed throughout the structure. Further stabilization is obtained by π–π stacking interactions between inversion-related quinoline systems and inversion-related pyridine rings, with respective centroid–centroid distances of 3.5866 (6) and 3.3980 (6) Å.

Related literature

For related radiopharmaceutical structures, see: Al-Dajani et al. (2010 ▶); Jain et al. (2004 ▶); Van der Berg et al. (2011 ▶).

Experimental

Crystal data

C₁₅H₁₃N₄O⁺·NO₃ ⁻
M _r = 327.30
Monoclinic,
a = 8.183 (2) Å
b = 11.768 (3) Å
c = 14.979 (4) Å
β = 98.37 (1)°
V = 1427.1 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 100 K
0.49 × 0.41 × 0.31 mm

Data collection

Bruker X8 APEXII KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ▶) T _min = 0.990, T _max = 0.994
26710 measured reflections
3555 independent reflections
3180 reflections with I > 2σ(I)
R _int = 0.023

Refinement

R[F ² > 2σ(F ²)] = 0.035
wR(F ²) = 0.1
S = 1.04
3555 reflections
233 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Data collection: APEX2 (Bruker, 2011 ▶); cell refinement: SAINT-Plus (Bruker, 2008 ▶); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg & Putz, 2005 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812036562/pk2439sup1.cif

e-68-o2808-sup1.cif^{(16.9KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812036562/pk2439Isup2.hkl

e-68-o2808-Isup2.hkl^{(170.8KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536812036562/pk2439Isup3.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—H1A⋯O3	0.892 (18)	2.019 (19)	2.8721 (14)	159.7 (16)
N1—H1B⋯O4ⁱ	0.836 (19)	2.204 (19)	3.0202 (14)	165.1 (16)
N2—H2A⋯O1	0.848 (19)	1.984 (18)	2.6458 (12)	134.1 (16)
N2—H2A⋯O3	0.848 (19)	2.496 (18)	3.2058 (12)	141.7 (15)
N3—H3A⋯O3ⁱⁱ	0.857 (17)	2.153 (17)	2.9652 (12)	158.2 (15)
N3—H3A⋯N4	0.857 (17)	2.288 (16)	2.6879 (15)	108.7 (13)
C4—H4⋯O3ⁱⁱ	0.93	2.44	3.1947 (14)	138
C11—H11⋯O4ⁱⁱⁱ	0.93	2.53	3.3460 (14)	147
C12—H12⋯O2^iv	0.93	2.5	3.2901 (14)	142
C14—H14⋯O2ⁱⁱ	0.93	2.55	3.1840 (14)	126

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) .

Acknowledgments

The authors would like to thank the Department of Chemistry of the University of the Free State, the NRF, NTeMBI, THRIP and Sasol Ltd for funding.

supplementary crystallographic information

Comment

The title compound was synthesized as a ligand for potential use in medical and radiopharmaceutical applications. The asymmetric unit in the title compound contains a C₁₅H₁₃N₄O cation and a NO₃^- counter ion. A range of N—H···N, N—H···O and C—H···O hydrogen interactions are observed throughout the structure. Further stabilization of the crystal structure is obtained by π-π stacking interactions between inversion-related quinolines and inversion-related pyridines with respective centroid-to-centroid distances of 3.5866 (6) Å and 3.3980 (6) Å (see Fig. 2). For similar structures that form part of our radiopharmaceutical research see: Al-Dajani et al. (2010); Jain et al. (2004) and Van der Berg et al. (2011).

Experimental

Under oxygen atmosphere: Quinaldic acid (0.8013 g, 4.627 mmol) was added as a solid in one portion to a suspension of 2,6-diaminopyridine (0.5000 g, 4.582 mmol) in pyridine (10 ml) and the mixture was stirred at 40 °C for 40 min. Triphenylphosphite (10 ml) was added dropwise over 10 minutes, after which the temperature was increased to 90–100 °C and stirred for a further 24 h. On cooling the precipitate was filtered, washed with H₂O (50 ml) and then MeOH (50 ml). The product was dissolved in diluted HNO₃ and left to stand at room temperature. Yellow crystals were obtained after five days.