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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 5| May 2012| Page o1475
doi:10.1107/S1600536812016637

2,4-Di­amino-6-methyl-1,3,5-triazin-1-ium hydrogen oxalate

Leila Narimania and Bohari M. Yamina*

aSchool of Chemical Sciences and Food Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
*Correspondence e-mail: bohari@pkrisc.cc.ukm.my

(Received 9 March 2012; accepted 16 April 2012; online 21 April 2012)

The title compound, C4H8N5+·C2HO4−, was obtained from the reaction of oxalic acid and 2,4-diamino-6-methyl-1,3,5-triazine. The protonated triazine ring is essentially planar with a maximum deviation of 0.035 (1) Å, but the hydrogen oxalate anion is less planar, with a maximum deviation of 0.131 (1) Å for both carbonyl O atoms. In the crystal, the ions are linked by inter­molecular N—H⋯O, N—H⋯N, O—H⋯O and C—H⋯O hydrogen bonds, forming a three-dimensional network. Weak π–π [centroid–centroid distance = 3.763 Å] and C—O⋯π inter­actions [O⋯centroid = 3.5300 (16) Å, C—O⋯centroid = 132.19 (10)°] are also present.

Related literature

For bond-length data see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]) and for a description of the Cambridge Structural Database, see: Allen (2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]). For background to triazine derivatives, see: Sebenik et al. (1989[Sebenik, A., Osredkar, U. & Zigon, M. (1989). Polym. Bull. 22, 155-161.]). For related structures, see: Kaczmarek et al. (2008[Kaczmarek, M., Radecka-Paryzek, W. & Kubicki, M. (2008). Acta Cryst. E64, o269.]); Xiao (2008[Xiao, Z.-H. (2008). Acta Cryst. E64, o411.]); Fan et al. (2009[Fan, Y., You, W., Qian, H.-F., Liu, J.-L. & Huang, W. (2009). Acta Cryst. E65, o494.]); Qian & Huang (2010[Qian, H.-F. & Huang, W. (2010). Acta Cryst. E66, o759.]).

[Scheme 1]

Experimental

Crystal data

  • C4H8N5+·C2HO4−

  • Mr = 215.18

  • Triclinic, [P \overline 1]

  • a = 5.6208 (12) Å

  • b = 7.9828 (17) Å

  • c = 10.857 (2) Å

  • α = 76.846 (4)°

  • β = 75.882 (4)°

  • γ = 75.954 (4)°

  • V = 450.92 (17) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.13 mm−1

  • T = 298 K

  • 0.50 × 0.22 × 0.19 mm
Data collection

  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.935, Tmax = 0.974

  • 5551 measured reflections

  • 1959 independent reflections

  • 1708 reflections with I > 2σ(I)

  • Rint = 0.023
Refinement

  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.113

  • S = 1.03

  • 1959 reflections

  • 145 parameters

  • 1 restraint

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

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.27 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N3—H3⋯O1i 0.95 (2) 1.77 (2) 2.7134 (17) 174 (2)
N3—H3⋯O4i 0.95 (2) 2.50 (2) 2.9841 (17) 111.7 (16)
O4—H4⋯O2 0.83 (2) 1.66 (2) 2.4921 (16) 175 (2)
N4—H4D⋯O3ii 0.86 2.17 2.9902 (19) 160
N4—H4E⋯N1iii 0.86 2.18 3.0399 (19) 174
N5—H5A⋯N2iv 0.86 2.14 3.0027 (19) 179
N5—H5B⋯O2v 0.86 2.28 2.8558 (17) 124
N5—H5B⋯O3v 0.86 2.59 3.2337 (19) 133
C4—H4C⋯O1vi 0.96 2.49 3.339 (2) 148
Symmetry codes: (i) x, y, z-1; (ii) x-1, y, z; (iii) -x, -y, -z+1; (iv) -x+1, -y+1, -z+1; (v) -x+2, -y+1, -z+1; (vi) x-1, y, z-1.

Data collection: SMART (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812016637/zq2157sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812016637/zq2157Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812016637/zq2157Isup3.cml

checkCIF report


Comment top

It is known that many triazine derivatives possess biological properties beside its usefullness as intermediates in the pharmaceutical industry (Sebenik et al., 1989). 2,4-diamino-6-1,3,5-triazine has been reported to co-crystallize with methanol (Kaczmarek et al., 2008) and ethanol (Xiao, 2008). On the other hand, the triazine nitrogen atom at position 1 can be easily protonated as in compound (C4H8N5)Cl (Qian & Huang, 2010) and (C4H8N5)NO3 (Fan et al., 2009) which were obtained from the normal acid-base reaction. The title compound is a similar salt but having a hydrogen oxalate as counter anion (Fig.1). The non hydrogen triazine ring, C1/N1/C2/N2/C3/N3, is planar with a maximum deviation of 0.035 (1) Å from the least square plane for N3 atom. The hydrogen oxalate anion O1/C1/O2/C2/O3/O4, is less planar with a maximum deviation of 0.131 (1) Å for O1 and O4 atoms. The bond lengths and angles are in normal ranges (Allen et al., 1987; Allen, 2002). In the crystal structure the molecules are linked by N—H···O, N—H···N, O—H···O and C—H···O intermolecular hydrogen bonds (symmetry codes as in Table 2) to form a three-dimensional network (Fig. 2). In addition, there are weak π–π interactions between the triazine ring centroids Cg1 (symmetry code: 1-x, -y, 1-z) with a distance of 3.763 Å and a C6—O3···π involving the triazine (C1/N1/C2/N2/C3/N3) centroid (symmetry code: 1-x, 1-y, 1-z) with a O3···Cg1 distance of 3.5300 (16) Å and a C6—O3—Cg1 bond angle of 132.19 (10)°.

Related literature top

For bond-length data see: Allen et al. (1987) and for a description of the Cambridge Structural Database, see: Allen (2002). For background to triazine derivatives, see: Sebenik et al. (1989). For related structures, see: Kaczmarek et al. (2008); Xiao (2008); Fan et al. (2009); Qian & Huang (2010).

Experimental top

10 ml aqueous solution of ammonium thiocyanate (0.152 g, 2 mmol) was added into a beaker containing oxalate acid (0.126 g, 1 mmol) and 2,4-diamino- 6-methyl-1,3,5-triazine (2 mmol) in 40 ml distilled water. After one week of evaporation at room temperature colourless crystals were obtained. Yield 92%; Melting point: 457.1–458.3 K.

Refinement top

After their location in the difference map, the H-atoms attached to the C and the amino N atoms were fixed geometrically at ideal positions and allowed to ride on the parent atoms with C—H = 0.93 Å and N—H = 0.86 Å, and with Uiso(H) = 1.5Ueq(C) and 1.2Ueq(N). However, the protonated amino and hydroxyl hydrogen atoms were located from the Fourier map and refined isotropically.

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound with 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. Packing diagram of the title compound viewed down a axis. The dashed lines denote hydrogen bonds.
2,4-Diamino-6-methyl-1,3,5-triazin-1-ium hydrogen oxalate top
Crystal data top
C4H8N5+·C2HO4−Z = 2
Mr = 215.18F(000) = 224
Triclinic, P1Dx = 1.585 Mg m−3
Hall symbol: -P 1Melting point = 492.2–492.5 K
a = 5.6208 (12) ÅMo Kα radiation, λ = 0.71073 Å
b = 7.9828 (17) ÅCell parameters from 1963 reflections
c = 10.857 (2) Åθ = 1.9–27.0°
α = 76.846 (4)°µ = 0.13 mm−1
β = 75.882 (4)°T = 298 K
γ = 75.954 (4)°Block, colourless
V = 450.92 (17) Å30.50 × 0.22 × 0.19 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		1959 independent reflections
Radiation source: fine-focus sealed tube1708 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 83.66 pixels mm-1θmax = 27.0°, θmin = 1.9°
ω scanh = −7→7
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		k = −10→10
Tmin = 0.935, Tmax = 0.974l = −13→13
5551 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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.113H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0664P)2 + 0.0976P]
where P = (Fo2 + 2Fc2)/3
1959 reflections(Δ/σ)max = 0.001
145 parametersΔρmax = 0.25 e Å−3
1 restraintΔρmin = −0.27 e Å−3
Crystal data top
C4H8N5+·C2HO4−γ = 75.954 (4)°
Mr = 215.18V = 450.92 (17) Å3
Triclinic, P1Z = 2
a = 5.6208 (12) ÅMo Kα radiation
b = 7.9828 (17) ŵ = 0.13 mm−1
c = 10.857 (2) ÅT = 298 K
α = 76.846 (4)°0.50 × 0.22 × 0.19 mm
β = 75.882 (4)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		1959 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		1708 reflections with I > 2σ(I)
Tmin = 0.935, Tmax = 0.974Rint = 0.023
5551 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0411 restraint
wR(F2) = 0.113H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.25 e Å−3
1959 reflectionsΔρmin = −0.27 e Å−3
145 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
O11.01323 (19)0.22067 (16)1.09284 (10)0.0435 (3)
O21.20977 (17)0.36561 (14)0.91142 (9)0.0383 (3)
O30.8189 (2)0.38620 (18)0.80042 (10)0.0490 (3)
O40.60164 (18)0.30135 (15)0.99698 (10)0.0401 (3)
H40.476 (3)0.322 (3)0.964 (2)0.076 (7)*
N10.2651 (2)0.08398 (15)0.40173 (11)0.0342 (3)
N20.3693 (2)0.31924 (15)0.46944 (11)0.0326 (3)
N30.5937 (2)0.21615 (15)0.28003 (11)0.0324 (3)
H30.733 (4)0.221 (2)0.2103 (19)0.049 (5)*
N40.0411 (2)0.18887 (17)0.58245 (12)0.0421 (3)
H4D0.01020.25720.63770.051*
H4E−0.05060.11300.59220.051*
N50.7025 (2)0.43757 (17)0.34456 (12)0.0393 (3)
H5A0.68270.50640.39830.047*
H5B0.82060.44150.27710.047*
C10.4493 (3)0.09606 (17)0.30219 (13)0.0307 (3)
C20.2280 (3)0.20042 (18)0.48339 (13)0.0316 (3)
C30.5530 (3)0.32675 (18)0.36537 (12)0.0302 (3)
C40.5070 (3)−0.0268 (2)0.21033 (15)0.0400 (4)
H4A0.5078−0.14420.25740.060*
H4B0.6685−0.02040.15600.060*
H4C0.38220.00480.15800.060*
C51.0268 (2)0.30348 (18)0.98158 (13)0.0296 (3)
C60.8009 (2)0.33563 (18)0.91548 (13)0.0301 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0288 (5)0.0646 (7)0.0332 (6)−0.0124 (5)−0.0051 (4)0.0009 (5)
O20.0237 (5)0.0565 (7)0.0344 (6)−0.0147 (4)−0.0014 (4)−0.0052 (5)
O30.0351 (6)0.0828 (9)0.0297 (6)−0.0157 (6)−0.0046 (4)−0.0093 (5)
O40.0234 (5)0.0622 (7)0.0351 (6)−0.0161 (5)−0.0038 (4)−0.0035 (5)
N10.0374 (7)0.0359 (6)0.0315 (6)−0.0161 (5)0.0015 (5)−0.0103 (5)
N20.0381 (6)0.0360 (6)0.0262 (6)−0.0158 (5)0.0009 (5)−0.0091 (5)
N30.0344 (6)0.0375 (6)0.0265 (6)−0.0140 (5)0.0022 (5)−0.0097 (5)
N40.0467 (7)0.0500 (8)0.0340 (7)−0.0264 (6)0.0091 (5)−0.0165 (6)
N50.0447 (7)0.0487 (7)0.0297 (6)−0.0263 (6)0.0048 (5)−0.0124 (5)
C10.0338 (7)0.0308 (6)0.0282 (7)−0.0090 (5)−0.0039 (5)−0.0061 (5)
C20.0353 (7)0.0343 (7)0.0263 (7)−0.0126 (6)−0.0019 (5)−0.0064 (5)
C30.0338 (7)0.0337 (7)0.0241 (6)−0.0117 (5)−0.0031 (5)−0.0045 (5)
C40.0471 (9)0.0389 (8)0.0360 (8)−0.0132 (6)0.0003 (6)−0.0147 (6)
C50.0222 (6)0.0375 (7)0.0291 (7)−0.0064 (5)−0.0002 (5)−0.0110 (5)
C60.0247 (6)0.0381 (7)0.0289 (7)−0.0084 (5)−0.0013 (5)−0.0103 (5)
Geometric parameters (Å, º) top
O1—C51.2322 (17)N4—C21.3112 (18)
O2—C51.2560 (16)N4—H4D0.8600
O3—C61.2093 (17)N4—H4E0.8600
O4—C61.2913 (16)N5—C31.3104 (18)
O4—H40.831 (10)N5—H5A0.8600
N1—C11.3054 (18)N5—H5B0.8600
N1—C21.3727 (17)C1—C41.4812 (19)
N2—C31.3329 (17)C4—H4A0.9600
N2—C21.3400 (17)C4—H4B0.9600
N3—C11.3465 (17)C4—H4C0.9600
N3—C31.3643 (18)C5—C61.5476 (19)
N3—H30.950 (19)
C6—O4—H4113.8 (16)N2—C2—N1124.86 (12)
C1—N1—C2116.03 (12)N5—C3—N2120.67 (12)
C3—N2—C2116.42 (11)N5—C3—N3118.55 (12)
C1—N3—C3119.67 (12)N2—C3—N3120.76 (12)
C1—N3—H3122.3 (11)C1—C4—H4A109.5
C3—N3—H3117.8 (11)C1—C4—H4B109.5
C2—N4—H4D120.0H4A—C4—H4B109.5
C2—N4—H4E120.0C1—C4—H4C109.5
H4D—N4—H4E120.0H4A—C4—H4C109.5
C3—N5—H5A120.0H4B—C4—H4C109.5
C3—N5—H5B120.0O1—C5—O2127.05 (13)
H5A—N5—H5B120.0O1—C5—C6118.95 (12)
N1—C1—N3122.20 (12)O2—C5—C6113.99 (12)
N1—C1—C4119.85 (12)O3—C6—O4126.24 (13)
N3—C1—C4117.95 (12)O3—C6—C5121.73 (12)
N4—C2—N2119.38 (12)O4—C6—C5112.03 (11)
N4—C2—N1115.75 (12)
C2—N1—C1—N3−0.4 (2)C2—N2—C3—N5−179.22 (13)
C2—N1—C1—C4178.65 (13)C2—N2—C3—N3−1.0 (2)
C3—N3—C1—N11.8 (2)C1—N3—C3—N5177.20 (13)
C3—N3—C1—C4−177.27 (13)C1—N3—C3—N2−1.1 (2)
C3—N2—C2—N4−178.67 (14)O1—C5—C6—O3−166.01 (14)
C3—N2—C2—N12.5 (2)O2—C5—C6—O313.0 (2)
C1—N1—C2—N4179.32 (13)O1—C5—C6—O413.65 (18)
C1—N1—C2—N2−1.8 (2)O2—C5—C6—O4−167.33 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···O1i0.95 (2)1.77 (2)2.7134 (17)174 (2)
N3—H3···O4i0.95 (2)2.50 (2)2.9841 (17)111.7 (16)
O4—H4···O20.83 (2)1.66 (2)2.4921 (16)175 (2)
N4—H4D···O3ii0.862.172.9902 (19)160
N4—H4E···N1iii0.862.183.0399 (19)174
N5—H5A···N2iv0.862.143.0027 (19)179
N5—H5B···O2v0.862.282.8558 (17)124
N5—H5B···O3v0.862.593.2337 (19)133
C4—H4C···O1vi0.962.493.339 (2)148
Symmetry codes: (i) x, y, z−1; (ii) x−1, y, z; (iii) −x, −y, −z+1; (iv) −x+1, −y+1, −z+1; (v) −x+2, −y+1, −z+1; (vi) x−1, y, z−1.

Experimental details

Crystal data
Chemical formulaC4H8N5+·C2HO4−
Mr215.18
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)5.6208 (12), 7.9828 (17), 10.857 (2)
α, β, γ (°)76.846 (4), 75.882 (4), 75.954 (4)
V (Å3)450.92 (17)
Z2
Radiation typeMo Kα
µ (mm−1)0.13
Crystal size (mm)0.50 × 0.22 × 0.19
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.935, 0.974
No. of measured, independent and
observed [I > 2σ(I)] reflections		5551, 1959, 1708
Rint0.023
(sin θ/λ)max (Å−1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.113, 1.03
No. of reflections1959
No. of parameters145
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.25, −0.27

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···O1i0.95 (2)1.77 (2)2.7134 (17)174 (2)
N3—H3···O4i0.95 (2)2.50 (2)2.9841 (17)111.7 (16)
O4—H4···O20.833 (19)1.661 (19)2.4921 (16)175 (2)
N4—H4D···O3ii0.862.172.9902 (19)160
N4—H4E···N1iii0.862.183.0399 (19)174
N5—H5A···N2iv0.862.143.0027 (19)179
N5—H5B···O2v0.862.282.8558 (17)124
N5—H5B···O3v0.862.593.2337 (19)133
C4—H4C···O1vi0.962.493.339 (2)148
Symmetry codes: (i) x, y, z−1; (ii) x−1, y, z; (iii) −x, −y, −z+1; (iv) −x+1, −y+1, −z+1; (v) −x+2, −y+1, −z+1; (vi) x−1, y, z−1.
 

Acknowledgements

The authors would like to thank the Malaysian Government and Universiti Kebangsaan Malaysia for the research grants UKM-GUP-NBT-68–27–110.

References

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ISSN: 2056-9890
Volume 68| Part 5| May 2012| Page o1475
doi:10.1107/S1600536812016637
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