2-Amino­pyrimidinium picrate

B Narayana; B K Sarojini; K Prakash Kamath; H S Yathirajan; Michael Bolte

doi:10.1107/S1600536807062599

. 2007 Dec 6;64(Pt 1):o117–o118. doi: 10.1107/S1600536807062599

2-Aminopyrimidinium picrate

B Narayana ^a, B K Sarojini ^b, K Prakash Kamath ^c, H S Yathirajan ^d, Michael Bolte ^e,^*

PMCID: PMC2915188 PMID: 21200681

Abstract

The geometric parameters of the title compound, C₄H₆N₃ ⁺·C₆H₂N₃O₇ ⁻, are in the usual ranges. While two nitro groups are almost coplanar with the aromatic picrate ring [dihedral angles 3.0 (2) and 4.4 (3)°], the third is significantly twisted out of this plane [dihedral angle 46.47 (8)°]. Anions and cations are connected via N—H⋯O hydrogen bonds. The molecules crystallize in planes parallel to (1 Inline graphic 1).

Related literature

For related literature, see: Barraclough & Smith (1995 ▶); Etter et al. (1990 ▶); Fischer et al. (2007 ▶); Goswami et al. (2000 ▶); Gueiffier et al. (1996 ▶); Katritzky et al. (2003 ▶); Rival et al. (1991 ▶); Sanfilippo et al. (1988 ▶); Scheinbeim & Schempp (1976 ▶); Schlueter et al. (2006 ▶); Tully et al. (1991 ▶); Yathirajan, Bindya et al. (2007a ▶,b ▶); Yathirajan, Mayekar et al. (2007 ▶); Yathirajan, Narayana et al. (2007 ▶).

Experimental

Crystal data

C₄H₆N₃ ⁺·C₆H₂N₃O₇ ⁻
M _r = 324.22
Triclinic,
a = 5.8803 (7) Å
b = 8.0025 (10) Å
c = 13.8108 (17) Å
α = 88.021 (10)°
β = 82.322 (9)°
γ = 88.739 (10)°
V = 643.59 (14) Å³
Z = 2
Mo Kα radiation
μ = 0.14 mm⁻¹
T = 173 (2) K
0.26 × 0.22 × 0.09 mm

Data collection

Stoe IPDSII two-circle diffractometer
Absorption correction: none
8757 measured reflections
2402 independent reflections
1927 reflections with I > 2σ(I)
R _int = 0.042

Refinement

R[F ² > 2σ(F ²)] = 0.036
wR(F ²) = 0.099
S = 1.01
2402 reflections
220 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Data collection: X-AREA (Stoe & Cie, 2001 ▶); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997 ▶); molecular graphics: PLATON (Spek, 2003 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536807062599/at2509sup1.cif

e-64-0o117-sup1.cif^{(17.4KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536807062599/at2509Isup2.hkl

e-64-0o117-Isup2.hkl^{(118KB, hkl)}

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⋯N6ⁱ	0.87 (2)	2.09 (2)	2.958 (2)	177.0 (18)
N1—H1B⋯O11	0.91 (2)	1.97 (2)	2.7577 (19)	143.7 (18)
N1—H1B⋯O17	0.91 (2)	2.50 (2)	3.2488 (18)	140.0 (17)
N2—H2⋯O11	0.90 (2)	1.84 (2)	2.6501 (16)	148.6 (19)
N2—H2⋯O12	0.90 (2)	2.31 (2)	2.9792 (18)	131.6 (17)

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Symmetry code: (i) Inline graphic .

Acknowledgments

BN thanks Mangalore University for the use of research facilities.

supplementary crystallographic information

Comment

Pyrimidine is a heterocyclic aromatic organic compound similar to benzene and pyridine, containing two nitrogen atoms at positions 1 and 3 of the six-member ring. A pyrimidine has many properties in common with pyridine, as the number of nitrogen atoms in the ring increases the ring π-electrons become less energetic and electrophilic aromatic substitution gets more difficult while nucleophilic aromatic substitution gets easier. Pyrimidines are important compounds in pharmaceutical chemistry as antiviral agents (Gueiffier et al., 1996), inotropic and β-blocking agents (Barraclough & Smith, 1995), antifungal agents (Rival et al. 1991), benzodiazepine receptor agonists (Tully et al.1991), and calcium channel blockers (Sanfilippo et al., 1988). The synthesis of imidazo[1,2-a]pyrimidines has been widely investigated and one of the most common strategies uses 2-aminopyrimidine as the starting material (Katritzky et al., 2003). The crystal structures of the following compounds have been previously reported, viz; 2-aminopyrimidine (Scheinbeim & Schempp, 1976), 1:1 hetero-assembly of 2-aminopyrimidine and (+)-camphoric acid (Goswami, et al., 2000), 2-aminopyrimidine-succinic acid (1:1) cocrystal (Etter et al., 1990), 5-aminopyrimidine (Schlueter et al., 2006), 5-bromopyrimidin-2(1H)-one (Yathirajan, Narayana, Ashalatha et al., 2007), ethyl 7-methyl-2-[4-(methylsulfanyl)benzylidene]-5-[4-(methylsulfanyl)phenyl]-3-oxo-2, 3-dihydro-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate (Fischer et al., 2007), 2-(4-methylbenzoyloxymethyl)-5-(5-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1 -yl)tetrahydrofuran-3-yl 4-methylbenzoate (Yathirajan, Mayekar, Sarojini et al., 2007), methyl (4-oxo-1-phenyl-4,5-dihydro-1H-pyrazolo[3,4-d]pyrimidin-5-yl)acetate (Yathirajan, Bindya, Sarojini et al., 2007a), ethyl (4-oxo-1-phenyl-1,4-dihydro-5H-pyrazolo[3,4-d]pyrimidin-5-yl)acetate (Yathirajan, Bindya, Sarojini et al., 2007b). In continuation to our work on picrates of biologically important molecules, we have prepared a new picrate of 2-aminopyrimidine, and its crystal structure is reported.

Geometric parameters of the title compound are in the usual ranges. Whereas two nitrogroups are almost coplanar with the aromatic picrate ring [dihedral angles 3.0 (2)° and 4.4 (3)°] the third one is significantly twisted [dihedral angle 46.47 (8)°] out of this plane Anions and cations are connected via N—H···O hydrogen bonds. The molecules crystallize in planes parallel to (1 - 2 1).

Experimental

2-Aminopyrimidine (0.95 g, 0.01 mol) was dissolved in 20 ml of ethanol. Picric acid (2.29 g, 0.01 mol) was dissolved in 10 ml of water. Both the solutions were mixed and to this, 5 ml of 5 M HCl was added and stirred for few minutes. The formed complex was filtered, dried and recrystallized from ethanol (m.p.: 413–415 K). Composition: Found (calculated): C 37.01(37.05), H 2.46(2.49), N 25.87% (25.92%).