organic compounds
2-Amino-4-methylpyrimidinium dihydrogen phosphate
aSolid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, Karnataka, India, and bDepartment of Chemistry, Kakatiya University, Warangal 506 009, India
*Correspondence e-mail: jyothisri97@yahoo.co.in
A charge-assisted hydrogen-bonding network involving N—H⋯O and O—H⋯O hydrogen bonds stabilizes the crystal of the title salt, C5H8N3+·H2PO4−. The dihydrogen phosphate anions form one-dimensional chains along [100], via O—H⋯O hydrogen bonds. The 2-amino-4-methylpyrimidinium cations are linked to these chains by means of two different kinds of N—H⋯O hydrogen bonds. Neighbouring chains are linked via C—H⋯N and C—H⋯O hydrogen bonds forming two-dimensional slab-like networks lying parallel to (01-1).
Related literature
Intriguing anion clusters formed by the supramolecular assembly of dihydrogen phosphates have been investigated recently (see: Hossain et al., 2012). Methylpyrimidine derivatives are known to be synthetic precursors to many bioactive pyrimidine derivatives (see: Xue et al., 1993). Metal complexes of pyrimidines (see: Zhu et al., 2008) and their proton transfer complexes with mineral acids are reported (see: Aakeroy et al., 2003). The infinite O—H⋯O hydrogen-bond chain present in this material is a structural feature suggestive of possible proton conducting behaviour (see: Haile et al., 2001).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell CrysAlis PRO (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and WinGX (Farrugia, 2012); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: PLATON (Spek, 2009).
Supporting information
10.1107/S160053681300648X/ds2227sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681300648X/ds2227Isup2.hkl
Supporting information file. DOI: 10.1107/S160053681300648X/ds2227Isup3.cml
The title compound was prepared by treating 2-amino 4-methyl pyramidine with phosphoric acid (H3PO4) in aqueous solution (Scheme 1) in 1:1 molar ratio. The crystals were harvested from the solution after 10 days and suitable crystal for single-crystal X-ray diffraction study were chosen using a polarizing microscope.
Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell
CrysAlis PRO (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXL97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008), WinGX(Farrugia, 2012); molecular graphics: Mercury 2.3 (Macrae et al. 2008); software used to prepare material for publication: PLATON (Spek, 2009).Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell
CrysAlis PRO (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and WinGX (Farrugia, 2012); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: PLATON (Spek, 2009).Fig. 1. ORTEP view of the title compound with the atom numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level. | |
Fig. 2. A view of supramolecular chain showing the hydrogen bonding between dihydrogen phosphate residues and the interlinked 2-amino-4-methylpyrimidine molecules. |
C5H8N3+·H2PO4− | Z = 2 |
Mr = 207.13 | F(000) = 216 |
Triclinic, P1 | Least Squares Treatment of 25 SET4 setting angles. |
Hall symbol: -P 1 | Dx = 1.585 Mg m−3 |
a = 6.1720 (2) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 7.5616 (3) Å | Cell parameters from 326 reflections |
c = 9.9216 (4) Å | θ = 2.8–26.0° |
α = 100.562 (3)° | µ = 0.31 mm−1 |
β = 99.821 (3)° | T = 295 K |
γ = 102.279 (4)° | Block, colourless |
V = 434.07 (3) Å3 | 0.25 × 0.20 × 0.18 mm |
Oxford Xcalibur Eos (Nova) CCD detector diffractometer | 1717 independent reflections |
Radiation source: Enhance (Mo) X-ray Source | 1546 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
ω scans | θmax = 26.0°, θmin = 2.8° |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) | h = −7→7 |
Tmin = 0.928, Tmax = 0.947 | k = −9→9 |
9718 measured reflections | l = −12→12 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.031 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.088 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0449P)2 + 0.1805P] where P = (Fo2 + 2Fc2)/3 |
1717 reflections | (Δ/σ)max < 0.001 |
125 parameters | Δρmax = 0.21 e Å−3 |
0 restraints | Δρmin = −0.34 e Å−3 |
C5H8N3+·H2PO4− | γ = 102.279 (4)° |
Mr = 207.13 | V = 434.07 (3) Å3 |
Triclinic, P1 | Z = 2 |
a = 6.1720 (2) Å | Mo Kα radiation |
b = 7.5616 (3) Å | µ = 0.31 mm−1 |
c = 9.9216 (4) Å | T = 295 K |
α = 100.562 (3)° | 0.25 × 0.20 × 0.18 mm |
β = 99.821 (3)° |
Oxford Xcalibur Eos (Nova) CCD detector diffractometer | 1717 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) | 1546 reflections with I > 2σ(I) |
Tmin = 0.928, Tmax = 0.947 | Rint = 0.027 |
9718 measured reflections |
R[F2 > 2σ(F2)] = 0.031 | 0 restraints |
wR(F2) = 0.088 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | Δρmax = 0.21 e Å−3 |
1717 reflections | Δρmin = −0.34 e Å−3 |
125 parameters |
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 on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.1136 (3) | 0.3869 (2) | 1.11795 (16) | 0.0405 (5) | |
N2 | −0.0464 (2) | 0.1740 (2) | 0.90738 (15) | 0.0332 (4) | |
N3 | 0.3480 (2) | 0.2530 (2) | 0.99937 (15) | 0.0326 (4) | |
C1 | 0.1379 (3) | 0.2712 (2) | 1.00803 (17) | 0.0293 (5) | |
C2 | −0.0146 (3) | 0.0613 (2) | 0.79698 (18) | 0.0341 (5) | |
C3 | 0.2007 (3) | 0.0371 (3) | 0.7852 (2) | 0.0407 (6) | |
C4 | 0.3796 (3) | 0.1362 (3) | 0.88869 (19) | 0.0386 (6) | |
C5 | −0.2202 (4) | −0.0381 (3) | 0.6843 (2) | 0.0507 (7) | |
P1 | 0.28422 (7) | 0.48498 (6) | 0.64883 (4) | 0.0283 (1) | |
O1 | 0.0685 (2) | 0.31898 (17) | 0.59152 (14) | 0.0418 (4) | |
O2 | 0.4901 (2) | 0.39299 (18) | 0.64980 (12) | 0.0365 (4) | |
O3 | 0.2949 (2) | 0.5709 (2) | 0.79898 (13) | 0.0439 (4) | |
O4 | 0.29115 (19) | 0.61556 (16) | 0.55043 (13) | 0.0336 (4) | |
H1N | 0.23060 | 0.44920 | 1.18240 | 0.0490* | |
H2N | −0.01930 | 0.40020 | 1.12510 | 0.0490* | |
H3 | 0.21960 | −0.04470 | 0.70830 | 0.0490* | |
H3N | 0.464 (4) | 0.319 (3) | 1.071 (2) | 0.048 (6)* | |
H4 | 0.52500 | 0.12390 | 0.88380 | 0.0460* | |
H5A | −0.31890 | −0.12620 | 0.71950 | 0.0760* | |
H5B | −0.17500 | −0.10210 | 0.60520 | 0.0760* | |
H5C | −0.29890 | 0.05020 | 0.65580 | 0.0760* | |
H1 | −0.03370 | 0.35420 | 0.54850 | 0.0630* | |
H2 | 0.53240 | 0.39280 | 0.57580 | 0.0550* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0258 (7) | 0.0530 (9) | 0.0348 (8) | 0.0121 (7) | 0.0011 (6) | −0.0069 (7) |
N2 | 0.0252 (7) | 0.0384 (8) | 0.0319 (7) | 0.0049 (6) | 0.0049 (6) | 0.0030 (6) |
N3 | 0.0238 (7) | 0.0423 (8) | 0.0309 (7) | 0.0087 (6) | 0.0047 (6) | 0.0069 (6) |
C1 | 0.0241 (8) | 0.0338 (8) | 0.0303 (8) | 0.0081 (6) | 0.0052 (6) | 0.0081 (7) |
C2 | 0.0327 (9) | 0.0334 (8) | 0.0331 (9) | 0.0033 (7) | 0.0079 (7) | 0.0048 (7) |
C3 | 0.0410 (10) | 0.0435 (10) | 0.0373 (10) | 0.0132 (8) | 0.0140 (8) | 0.0003 (8) |
C4 | 0.0315 (9) | 0.0494 (10) | 0.0403 (10) | 0.0173 (8) | 0.0134 (8) | 0.0103 (8) |
C5 | 0.0393 (11) | 0.0546 (12) | 0.0424 (11) | −0.0023 (9) | 0.0047 (8) | −0.0077 (9) |
P1 | 0.0201 (2) | 0.0388 (3) | 0.0242 (2) | 0.0076 (2) | 0.0030 (2) | 0.0046 (2) |
O1 | 0.0294 (7) | 0.0421 (7) | 0.0492 (8) | 0.0029 (5) | −0.0041 (6) | 0.0177 (6) |
O2 | 0.0300 (6) | 0.0563 (8) | 0.0293 (6) | 0.0201 (6) | 0.0081 (5) | 0.0126 (6) |
O3 | 0.0298 (7) | 0.0705 (9) | 0.0280 (7) | 0.0165 (6) | 0.0057 (5) | −0.0015 (6) |
O4 | 0.0238 (6) | 0.0396 (6) | 0.0379 (7) | 0.0078 (5) | 0.0066 (5) | 0.0106 (5) |
P1—O3 | 1.4964 (13) | N1—H2N | 0.8600 |
P1—O1 | 1.5623 (14) | N1—H1N | 0.8600 |
P1—O2 | 1.5725 (14) | N3—H3N | 0.90 (2) |
P1—O4 | 1.5098 (13) | C2—C5 | 1.492 (3) |
O1—H1 | 0.8200 | C2—C3 | 1.401 (3) |
O2—H2 | 0.8200 | C3—C4 | 1.347 (3) |
N1—C1 | 1.319 (2) | C3—H3 | 0.9300 |
N2—C2 | 1.329 (2) | C4—H4 | 0.9300 |
N2—C1 | 1.349 (2) | C5—H5C | 0.9600 |
N3—C1 | 1.348 (2) | C5—H5A | 0.9600 |
N3—C4 | 1.347 (2) | C5—H5B | 0.9600 |
P1···H3Ni | 2.89 (2) | C2···C1ix | 3.481 (2) |
P1···H2Nii | 3.1000 | C2···O1 | 3.099 (2) |
P1···H1iii | 2.8900 | C3···O1 | 3.257 (2) |
P1···H1Ni | 3.0600 | C4···O2 | 3.395 (2) |
P1···H2iv | 2.8800 | C5···O1 | 3.277 (3) |
O1···C3 | 3.257 (2) | C5···H4viii | 2.9800 |
O1···C5 | 3.277 (3) | H1···P1iii | 2.8900 |
O1···O4iii | 2.6100 (18) | H1···O4iii | 1.8000 |
O1···C2 | 3.099 (2) | H1···H1iii | 2.5500 |
O2···N1i | 3.000 (2) | H1N···H2i | 2.5200 |
O2···C4 | 3.395 (2) | H1N···H3N | 2.2400 |
O2···O4iv | 2.5843 (17) | H1N···P1i | 3.0600 |
O3···N1ii | 2.845 (2) | H1N···O2i | 2.1400 |
O3···N3i | 2.6276 (19) | H2···O4iv | 1.8000 |
O4···O1iii | 2.6100 (18) | H2···H1Ni | 2.5200 |
O4···O2iv | 2.5843 (17) | H2···H2iv | 2.4500 |
O1···H5Bv | 2.5800 | H2···P1iv | 2.8800 |
O2···H1Ni | 2.1400 | H2N···P1ii | 3.1000 |
O3···H3Ni | 1.73 (2) | H2N···O3ii | 2.0100 |
O3···H2Nii | 2.0100 | H3···O4x | 2.9100 |
O4···H2iv | 1.8000 | H3···H5B | 2.3900 |
O4···H1iii | 1.8000 | H3N···H1N | 2.2400 |
O4···H3vi | 2.9100 | H3N···P1i | 2.89 (2) |
O4···H5Avii | 2.8000 | H3N···O3i | 1.73 (2) |
N1···O2i | 3.000 (2) | H4···N2xi | 2.5500 |
N1···O3ii | 2.845 (2) | H4···C5xi | 2.9800 |
N3···O3i | 2.6276 (19) | H5A···O4xii | 2.8000 |
N2···H4viii | 2.5500 | H5B···H3 | 2.3900 |
C1···C2ix | 3.481 (2) | H5B···O1v | 2.5800 |
O3—P1—O4 | 115.79 (8) | N2—C1—N3 | 121.54 (15) |
O1—P1—O3 | 109.84 (8) | N2—C2—C3 | 122.14 (16) |
O1—P1—O4 | 109.55 (7) | N2—C2—C5 | 116.73 (17) |
O1—P1—O2 | 104.78 (7) | C3—C2—C5 | 121.13 (17) |
O2—P1—O4 | 110.13 (7) | C2—C3—C4 | 117.84 (18) |
O2—P1—O3 | 106.13 (7) | N3—C4—C3 | 120.03 (18) |
P1—O1—H1 | 109.00 | C2—C3—H3 | 121.00 |
P1—O2—H2 | 109.00 | C4—C3—H3 | 121.00 |
C1—N2—C2 | 117.90 (15) | C3—C4—H4 | 120.00 |
C1—N3—C4 | 120.52 (15) | N3—C4—H4 | 120.00 |
H1N—N1—H2N | 120.00 | C2—C5—H5B | 109.00 |
C1—N1—H1N | 120.00 | C2—C5—H5C | 109.00 |
C1—N1—H2N | 120.00 | C2—C5—H5A | 109.00 |
C1—N3—H3N | 117.5 (15) | H5A—C5—H5C | 109.00 |
C4—N3—H3N | 121.9 (15) | H5B—C5—H5C | 109.00 |
N1—C1—N3 | 118.80 (16) | H5A—C5—H5B | 110.00 |
N1—C1—N2 | 119.66 (17) | ||
C2—N2—C1—N1 | 178.81 (15) | C4—N3—C1—N2 | 0.1 (2) |
C2—N2—C1—N3 | −1.3 (2) | C1—N3—C4—C3 | 0.3 (3) |
C1—N2—C2—C3 | 2.1 (2) | N2—C2—C3—C4 | −1.7 (3) |
C1—N2—C2—C5 | −177.38 (16) | C5—C2—C3—C4 | 177.75 (19) |
C4—N3—C1—N1 | −179.98 (18) | C2—C3—C4—N3 | 0.4 (3) |
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x, −y+1, −z+2; (iii) −x, −y+1, −z+1; (iv) −x+1, −y+1, −z+1; (v) −x, −y, −z+1; (vi) x, y+1, z; (vii) x+1, y+1, z; (viii) x−1, y, z; (ix) −x, −y, −z+2; (x) x, y−1, z; (xi) x+1, y, z; (xii) x−1, y−1, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···O4iii | 0.82 | 1.80 | 2.6100 (18) | 168 |
N1—H1N···O2i | 0.86 | 2.14 | 3.000 (2) | 177 |
O2—H2···O4iv | 0.82 | 1.80 | 2.5843 (17) | 161 |
N1—H2N···O3ii | 0.86 | 2.01 | 2.845 (2) | 163 |
N3—H3N···O3i | 0.90 (2) | 1.73 (2) | 2.6276 (19) | 173 (2) |
C4—H4···N2xi | 0.93 | 2.55 | 3.463 (2) | 166 |
C5—H5B···O1v | 0.96 | 2.58 | 3.531 (3) | 171 |
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x, −y+1, −z+2; (iii) −x, −y+1, −z+1; (iv) −x+1, −y+1, −z+1; (v) −x, −y, −z+1; (xi) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C5H8N3+·H2PO4− |
Mr | 207.13 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 295 |
a, b, c (Å) | 6.1720 (2), 7.5616 (3), 9.9216 (4) |
α, β, γ (°) | 100.562 (3), 99.821 (3), 102.279 (4) |
V (Å3) | 434.07 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.31 |
Crystal size (mm) | 0.25 × 0.20 × 0.18 |
Data collection | |
Diffractometer | Oxford Xcalibur Eos (Nova) CCD detector diffractometer |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2006) |
Tmin, Tmax | 0.928, 0.947 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9718, 1717, 1546 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.031, 0.088, 1.08 |
No. of reflections | 1717 |
No. of parameters | 125 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.21, −0.34 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis PRO (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and WinGX (Farrugia, 2012), Mercury (Macrae et al., 2008), PLATON (Spek, 2009).
P1—O3 | 1.4964 (13) | N2—C2 | 1.329 (2) |
P1—O1 | 1.5623 (14) | N2—C1 | 1.349 (2) |
P1—O2 | 1.5725 (14) | N3—C1 | 1.348 (2) |
P1—O4 | 1.5098 (13) | N3—C4 | 1.347 (2) |
N1—C1 | 1.319 (2) | ||
O3—P1—O4 | 115.79 (8) | C1—N3—C4 | 120.52 (15) |
O1—P1—O3 | 109.84 (8) | N1—C1—N3 | 118.80 (16) |
O1—P1—O4 | 109.55 (7) | N1—C1—N2 | 119.66 (17) |
O1—P1—O2 | 104.78 (7) | N2—C1—N3 | 121.54 (15) |
O2—P1—O4 | 110.13 (7) | N2—C2—C3 | 122.14 (16) |
O2—P1—O3 | 106.13 (7) | N2—C2—C5 | 116.73 (17) |
C1—N2—C2 | 117.90 (15) | N3—C4—C3 | 120.03 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···O4i | 0.8200 | 1.8000 | 2.6100 (18) | 168.00 |
N1—H1N···O2ii | 0.8600 | 2.1400 | 3.000 (2) | 177.00 |
O2—H2···O4iii | 0.8200 | 1.8000 | 2.5843 (17) | 161.00 |
N1—H2N···O3iv | 0.8600 | 2.0100 | 2.845 (2) | 163.00 |
N3—H3N···O3ii | 0.90 (2) | 1.73 (2) | 2.6276 (19) | 173 (2) |
C4—H4···N2v | 0.9300 | 2.5500 | 3.463 (2) | 166.00 |
C5—H5B···O1vi | 0.9600 | 2.5800 | 3.531 (3) | 171.00 |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y+1, −z+2; (iii) −x+1, −y+1, −z+1; (iv) −x, −y+1, −z+2; (v) x+1, y, z; (vi) −x, −y, −z+1. |
Acknowledgements
SPT thanks UGC for an SRF, JS thanks UGC for research funding. SPT and SJ acknowledge Professor T. N. Guru Row for his support and XRD facility at IISc.
References
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The title compound, a multicomponent crystal, AMHP, crystallizes in triclinic P-1, with a protonated 2-amino-4-methylpyrimidine molecule and a dihydrogenphosphate moiety in the asymmetric unit (Fig. 1). The dihydrogenphosphate residue forms a chain via O—H···O hydrogen bonds. 2-Amino-4-methylpyrimidinium cations are linked to these chains by means of two different kinds of N—H···O hydrogen bonds. The crystal packing is stabilized by N—H···O and O—H···O hydrogen bonds and the resulting supramolecular assembly is shown in Figure 2. The infinite hydrogen bond chains present in this structure are of special interest due to the anticipated proton conductivity of the material (see: Haile et al.2001).