organic compounds
2,6-Diamino-4-chloropyrimidinium 4-carboxybutanoate
aDepartment of Chemistry, Government Arts College (Autonomous), Thanthonimalai, Karur 639 005, Tamil Nadu, India, and bSchool of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: manavaibala@gmail.com
In the title molecular salt, C4H6ClN4+·C5H7O4−, the cation is essentially planar, with a maximum deviation of 0.037 (1) Å for all non-H atoms. The anions are self-assembled through O—H⋯O hydrogen bonds, forming a supramolecular zigzag chain with graph-set notation C(8). In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxylate O atoms of the anion via a pair of N—H⋯O hydrogen bonds with an R22(8) ring motif. This motif further self-organizes through N—H⋯O and O—H⋯O hydrogen bonds, generating an array of six hydrogen bonds, the rings having graph-set notation R32(8), R22(8), R42(8), R22(8) and R32(8). In addition, another type of R22(8) motif is formed by inversion-related pyrimidinium cations via N—H⋯N hydrogen bonds, forming a two-dimensional network parallel to (101).
Keywords: crystal structure.
CCDC reference: 1010934
Related literature
For applications of pyrimidine derivatives, see: Condon et al. (1993); Maeno et al. (1990); Gilchrist (1997). For applications of glutaric acid, see: Windholz (1976). For the conformation of glutaric acid, see: Saraswathi et al. (2001); Stanley et al. (2002). For related structures, see: Thanigaimani et al. (2012a,b); Thanigaimani & Muthiah (2010). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supporting information
CCDC reference: 1010934
10.1107/S1600536814015220/sj5418sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536814015220/sj5418Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536814015220/sj5418Isup3.cml
Hot methanol solutions (20 ml) of 2,6-diamino-4-chloropyrimidine (36 mg, Aldrich) and glutaric acid (33 mg, Merck) were mixed and warmed over a heating magnetic stirrer hotplate for a few minutes. The resulting solution was allowed to cool slowly at room temperature and crystals of the title compound (I) appeared after a few days.
O– and N-bound H atoms were located in a difference Fourier maps and allowed to be refined freely [O–H = 0.94 (3) Å and N–H = 0.85 (2)–0.94 (3) Å]. The remaining hydrogen atoms were positioned geometrically [C–H= 0.93–0.97 Å] and were refined using a riding model, with Uiso(H)=1.2 Ueq(C).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).Fig. 1. The molecular structure of the title compound with atom labels with 50% probability displacement ellipsoids. | |
Fig. 2. Carboxyl-carboxylate interactions made up of hydrogen glutarate anion | |
Fig. 3. The crystal packing of (I), showing hydrogen-bonded (dashed lines) two-dimensional networks parallel to the bc-plane. The H atoms not involved in the intermolecular interactions have been omitted for clarity. |
C4H6ClN4+·C5H7O4− | F(000) = 576 |
Mr = 276.68 | Dx = 1.557 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 9974 reflections |
a = 5.1582 (1) Å | θ = 2.3–28.9° |
b = 23.2339 (5) Å | µ = 0.34 mm−1 |
c = 9.8858 (2) Å | T = 296 K |
β = 94.7949 (12)° | Block, colourless |
V = 1180.62 (4) Å3 | 0.54 × 0.24 × 0.21 mm |
Z = 4 |
Bruker SMART APEXII DUO CCD area-detector diffractometer | 3121 independent reflections |
Radiation source: fine-focus sealed tube | 2402 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.030 |
ϕ and ω scans | θmax = 29.0°, θmin = 1.8° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −7→7 |
Tmin = 0.838, Tmax = 0.932 | k = −31→31 |
31054 measured reflections | l = −13→13 |
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)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.099 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0384P)2 + 0.4919P] where P = (Fo2 + 2Fc2)/3 |
3121 reflections | (Δ/σ)max < 0.001 |
187 parameters | Δρmax = 0.24 e Å−3 |
0 restraints | Δρmin = −0.27 e Å−3 |
C4H6ClN4+·C5H7O4− | V = 1180.62 (4) Å3 |
Mr = 276.68 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 5.1582 (1) Å | µ = 0.34 mm−1 |
b = 23.2339 (5) Å | T = 296 K |
c = 9.8858 (2) Å | 0.54 × 0.24 × 0.21 mm |
β = 94.7949 (12)° |
Bruker SMART APEXII DUO CCD area-detector diffractometer | 3121 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2402 reflections with I > 2σ(I) |
Tmin = 0.838, Tmax = 0.932 | Rint = 0.030 |
31054 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.099 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.04 | Δρmax = 0.24 e Å−3 |
3121 reflections | Δρmin = −0.27 e Å−3 |
187 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.16574 (11) | 0.356710 (18) | 0.02821 (5) | 0.05343 (16) | |
O1 | 0.9550 (2) | 0.61641 (5) | 0.37186 (13) | 0.0452 (3) | |
O2 | 0.6452 (2) | 0.58299 (5) | 0.49189 (13) | 0.0457 (3) | |
O4 | 0.2839 (3) | 0.82514 (5) | 0.75083 (13) | 0.0456 (3) | |
O3 | 0.1675 (3) | 0.73460 (5) | 0.78386 (15) | 0.0566 (4) | |
N1 | 0.0480 (3) | 0.51507 (5) | 0.25300 (13) | 0.0313 (3) | |
N2 | 0.3649 (3) | 0.55724 (6) | 0.13291 (16) | 0.0410 (4) | |
N3 | 0.2615 (3) | 0.46281 (5) | 0.08966 (13) | 0.0336 (3) | |
N4 | −0.2630 (3) | 0.47569 (6) | 0.37842 (15) | 0.0388 (3) | |
C1 | 0.2246 (3) | 0.51130 (6) | 0.15836 (15) | 0.0306 (3) | |
C2 | 0.1140 (3) | 0.41827 (6) | 0.12105 (16) | 0.0326 (3) | |
C3 | −0.0637 (3) | 0.41698 (6) | 0.21495 (16) | 0.0352 (4) | |
H3A | −0.1570 | 0.3839 | 0.2319 | 0.042* | |
C4 | −0.0981 (3) | 0.46873 (6) | 0.28496 (15) | 0.0306 (3) | |
C5 | 0.7825 (3) | 0.62305 (6) | 0.45526 (16) | 0.0317 (3) | |
C6 | 0.7534 (3) | 0.68300 (6) | 0.51111 (17) | 0.0333 (3) | |
H6A | 0.7280 | 0.7095 | 0.4353 | 0.040* | |
H6B | 0.9152 | 0.6935 | 0.5623 | 0.040* | |
C7 | 0.5326 (3) | 0.69147 (6) | 0.60184 (16) | 0.0344 (4) | |
H7A | 0.3721 | 0.6768 | 0.5565 | 0.041* | |
H7B | 0.5692 | 0.6700 | 0.6854 | 0.041* | |
C8 | 0.5006 (3) | 0.75477 (7) | 0.63429 (18) | 0.0371 (4) | |
H8A | 0.6670 | 0.7694 | 0.6725 | 0.045* | |
H8B | 0.4566 | 0.7752 | 0.5499 | 0.045* | |
C9 | 0.2995 (3) | 0.76880 (6) | 0.73030 (16) | 0.0321 (3) | |
H1N4 | −0.364 (4) | 0.4456 (9) | 0.3998 (19) | 0.050 (6)* | |
H2N2 | 0.469 (4) | 0.5531 (8) | 0.071 (2) | 0.049 (6)* | |
H1N2 | 0.341 (4) | 0.5903 (9) | 0.171 (2) | 0.048 (5)* | |
H2N4 | −0.282 (4) | 0.5094 (9) | 0.4155 (19) | 0.046 (5)* | |
H1N1 | 0.023 (4) | 0.5489 (9) | 0.294 (2) | 0.052 (6)* | |
H1O4 | 0.153 (6) | 0.8363 (12) | 0.805 (3) | 0.092 (8)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0729 (4) | 0.0304 (2) | 0.0614 (3) | −0.0024 (2) | 0.0322 (3) | −0.01516 (19) |
O1 | 0.0534 (8) | 0.0268 (6) | 0.0612 (8) | −0.0052 (5) | 0.0391 (6) | −0.0065 (5) |
O2 | 0.0517 (8) | 0.0280 (6) | 0.0626 (8) | −0.0071 (5) | 0.0359 (6) | −0.0052 (5) |
O4 | 0.0556 (8) | 0.0281 (6) | 0.0579 (8) | 0.0063 (5) | 0.0328 (6) | −0.0002 (5) |
O3 | 0.0675 (9) | 0.0356 (7) | 0.0734 (9) | −0.0098 (6) | 0.0450 (8) | −0.0061 (6) |
N1 | 0.0372 (8) | 0.0229 (6) | 0.0365 (7) | 0.0004 (5) | 0.0189 (6) | −0.0024 (5) |
N2 | 0.0496 (9) | 0.0274 (7) | 0.0505 (9) | −0.0047 (6) | 0.0301 (7) | −0.0040 (6) |
N3 | 0.0393 (8) | 0.0270 (6) | 0.0370 (7) | 0.0013 (5) | 0.0182 (6) | −0.0028 (5) |
N4 | 0.0454 (9) | 0.0291 (7) | 0.0457 (8) | −0.0021 (6) | 0.0270 (7) | −0.0021 (6) |
C1 | 0.0345 (8) | 0.0266 (7) | 0.0327 (8) | 0.0026 (6) | 0.0142 (6) | 0.0015 (6) |
C2 | 0.0394 (9) | 0.0245 (7) | 0.0355 (8) | 0.0024 (6) | 0.0117 (7) | −0.0034 (6) |
C3 | 0.0422 (9) | 0.0246 (7) | 0.0411 (9) | −0.0040 (6) | 0.0177 (7) | −0.0010 (6) |
C4 | 0.0332 (8) | 0.0267 (7) | 0.0338 (8) | 0.0014 (6) | 0.0128 (6) | 0.0024 (6) |
C5 | 0.0326 (8) | 0.0271 (7) | 0.0376 (8) | −0.0006 (6) | 0.0153 (7) | −0.0017 (6) |
C6 | 0.0340 (8) | 0.0262 (7) | 0.0418 (8) | −0.0014 (6) | 0.0157 (7) | −0.0046 (6) |
C7 | 0.0371 (9) | 0.0280 (7) | 0.0404 (9) | 0.0004 (6) | 0.0166 (7) | −0.0033 (6) |
C8 | 0.0418 (9) | 0.0286 (7) | 0.0439 (9) | −0.0002 (7) | 0.0212 (8) | −0.0033 (7) |
C9 | 0.0344 (8) | 0.0294 (7) | 0.0335 (8) | 0.0017 (6) | 0.0093 (7) | −0.0028 (6) |
Cl1—C2 | 1.7321 (15) | N4—H1N4 | 0.91 (2) |
O1—C5 | 1.2720 (17) | N4—H2N4 | 0.87 (2) |
O2—C5 | 1.2416 (18) | C2—C3 | 1.358 (2) |
O4—C9 | 1.3281 (18) | C3—C4 | 1.406 (2) |
O4—H1O4 | 0.94 (3) | C3—H3A | 0.9300 |
O3—C9 | 1.1982 (19) | C5—C6 | 1.511 (2) |
N1—C1 | 1.3624 (18) | C6—C7 | 1.520 (2) |
N1—C4 | 1.3661 (19) | C6—H6A | 0.9700 |
N1—H1N1 | 0.90 (2) | C6—H6B | 0.9700 |
N2—C1 | 1.325 (2) | C7—C8 | 1.517 (2) |
N2—H2N2 | 0.85 (2) | C7—H7A | 0.9700 |
N2—H1N2 | 0.87 (2) | C7—H7B | 0.9700 |
N3—C2 | 1.3361 (19) | C8—C9 | 1.499 (2) |
N3—C1 | 1.3373 (18) | C8—H8A | 0.9700 |
N4—C4 | 1.3173 (19) | C8—H8B | 0.9700 |
C9—O4—H1O4 | 114.7 (17) | O2—C5—C6 | 120.54 (13) |
C1—N1—C4 | 121.44 (13) | O1—C5—C6 | 116.42 (13) |
C1—N1—H1N1 | 119.6 (13) | C5—C6—C7 | 115.92 (12) |
C4—N1—H1N1 | 118.9 (13) | C5—C6—H6A | 108.3 |
C1—N2—H2N2 | 115.6 (13) | C7—C6—H6A | 108.3 |
C1—N2—H1N2 | 121.9 (13) | C5—C6—H6B | 108.3 |
H2N2—N2—H1N2 | 122.2 (19) | C7—C6—H6B | 108.3 |
C2—N3—C1 | 115.26 (12) | H6A—C6—H6B | 107.4 |
C4—N4—H1N4 | 119.0 (12) | C8—C7—C6 | 110.52 (12) |
C4—N4—H2N4 | 120.4 (13) | C8—C7—H7A | 109.5 |
H1N4—N4—H2N4 | 120.4 (18) | C6—C7—H7A | 109.5 |
N2—C1—N3 | 118.62 (13) | C8—C7—H7B | 109.5 |
N2—C1—N1 | 119.06 (14) | C6—C7—H7B | 109.5 |
N3—C1—N1 | 122.32 (13) | H7A—C7—H7B | 108.1 |
N3—C2—C3 | 127.27 (14) | C9—C8—C7 | 115.99 (13) |
N3—C2—Cl1 | 113.61 (11) | C9—C8—H8A | 108.3 |
C3—C2—Cl1 | 119.11 (12) | C7—C8—H8A | 108.3 |
C2—C3—C4 | 115.95 (14) | C9—C8—H8B | 108.3 |
C2—C3—H3A | 122.0 | C7—C8—H8B | 108.3 |
C4—C3—H3A | 122.0 | H8A—C8—H8B | 107.4 |
N4—C4—N1 | 117.81 (14) | O3—C9—O4 | 122.82 (14) |
N4—C4—C3 | 124.44 (14) | O3—C9—C8 | 125.75 (14) |
N1—C4—C3 | 117.75 (13) | O4—C9—C8 | 111.43 (13) |
O2—C5—O1 | 123.03 (14) | ||
C2—N3—C1—N2 | 179.75 (16) | C1—N1—C4—C3 | −1.2 (2) |
C2—N3—C1—N1 | −0.4 (2) | C2—C3—C4—N4 | 179.39 (17) |
C4—N1—C1—N2 | −178.74 (16) | C2—C3—C4—N1 | 0.0 (2) |
C4—N1—C1—N3 | 1.4 (2) | O2—C5—C6—C7 | −5.6 (2) |
C1—N3—C2—C3 | −0.9 (3) | O1—C5—C6—C7 | 175.33 (15) |
C1—N3—C2—Cl1 | 179.29 (12) | C5—C6—C7—C8 | −171.88 (15) |
N3—C2—C3—C4 | 1.1 (3) | C6—C7—C8—C9 | −176.36 (15) |
Cl1—C2—C3—C4 | −179.10 (13) | C7—C8—C9—O3 | 1.1 (3) |
C1—N1—C4—N4 | 179.40 (15) | C7—C8—C9—O4 | −179.20 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
N4—H1N4···O2i | 0.91 (2) | 1.99 (2) | 2.7950 (19) | 147.4 (18) |
N2—H2N2···N3ii | 0.85 (2) | 2.23 (2) | 3.079 (2) | 176.9 (18) |
N2—H1N2···O4iii | 0.87 (2) | 2.15 (2) | 3.0140 (18) | 175.5 (18) |
N4—H2N4···O2iv | 0.87 (2) | 1.92 (2) | 2.7904 (18) | 175 (2) |
N1—H1N1···O1iv | 0.90 (2) | 1.80 (2) | 2.6924 (17) | 177 (2) |
O4—H1O4···O1v | 0.94 (3) | 1.67 (3) | 2.5480 (15) | 155 (3) |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y+1, −z; (iii) x, −y+3/2, z−1/2; (iv) x−1, y, z; (v) x−1, −y+3/2, z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N4—H1N4···O2i | 0.91 (2) | 1.99 (2) | 2.7950 (19) | 147.4 (18) |
N2—H2N2···N3ii | 0.85 (2) | 2.23 (2) | 3.079 (2) | 176.9 (18) |
N2—H1N2···O4iii | 0.87 (2) | 2.15 (2) | 3.0140 (18) | 175.5 (18) |
N4—H2N4···O2iv | 0.87 (2) | 1.92 (2) | 2.7904 (18) | 175 (2) |
N1—H1N1···O1iv | 0.90 (2) | 1.80 (2) | 2.6924 (17) | 177 (2) |
O4—H1O4···O1v | 0.94 (3) | 1.67 (3) | 2.5480 (15) | 155 (3) |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y+1, −z; (iii) x, −y+3/2, z−1/2; (iv) x−1, y, z; (v) x−1, −y+3/2, z+1/2. |
Footnotes
‡Thomson Reuters ResearcherID: A-5599-2009.
Acknowledgements
The authors thank the Malaysian Government and Universiti Sains Malaysia (USM) for the research facilities and Fundamental Research Grant Scheme (FRGS) No. 203/PFIZIK/6711171 to conduct this work. KT thanks The Academy of Sciences for the Developing World and USM for the TWAS–USM fellowship.
References
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Pyrimidine derivatives are very important molecules in biology and have many application in the areas of pesticide and pharmaceutical agents (Condon et al., 1993). For example, imazosulfuron, ethirmol and mepanipyrim have been commercialized as agrochemicals (Maeno et al., 1990). Pyrimidine derivatives have also been developed as antiviral agents, such as AZT, which is the most widely-used anti-AIDS drug (Gilchrist, 1997). Glutaric acid (pentanedioic acid) is a dicarboxylic acid with five carbon atoms, occurring in plant and animal tissues. Glutaric acid is found in the blood and urine. It is used in the synthesis of phamaceuticals, surfactants and metal finishing compounds. Alpha-ketoglutaic acid is used in dietary supplements to improve protein synthesis (Windholz, 1976). The related crystal structures of Bis(2,6-diamino-4-chloropyrimidin-1-ium) fumarate (Thanigaimani et al., 2012a) and 2,6-diamno-4-chloropyrimidine-benzoic acid (1/1) (Thanigaimani et al., 2012b) have been recently reported. In order to study some interesting hydrogen bonding interactions, the crystal structure determination of the title compound, (I), was carried out.
The asymmetric unit of the title compound consists of a 2,6-diamino-4-chloropyrimidinium cation and a hydrogen glutarate anion (Fig. 1). The 2,6-diamino-4-chloropyrimidinium cation is essentially planar, with a maximum deviation of 0.016 (1) Å for atom N1. In the 2,6-diamino-4-chloropyrimidinium cation, a wider than normal angle [C1–N1–C6 = 121.44 (12)°] is subtented at the protonated N1 atom. In the hydrogen glutarate anion, C5/C6/C7/C8/C9 plane makes a dihedral angle of 9.67 (12) ° with 2,6-diamino-4-chloropyrimidinium cation. The backbone conformation of the hydrogen glutarate anion can be described by the two torsion angles C5–C6–C7–C8 of -171.89 (13)° and C6–C7–C8–C9 of -176.36 (13)°. As evident from the torsion angles, the hydrogenglutarate anion is in a fully extended conformation (Saraswathi et al., 2001) of the two carboxyl groups, one is deprotonated while the other is not. The bond lengths and angles (Allen et al., 1987) are within normal ranges.
In the crystal packing, the protonated N atom the 2-amino group of the cation are hydrogen bonded to the carboxylate O atoms of the anion via a pair of N1—H1N1···O1iv and N4—H2N4···O2iv hydrogen bonds (symmetry code in Table 1), forming R22(8) (Bernstein et al., 1995) ring motif. This motif further self organizes through N4—H1N4···O2i, N2—H1N2···O4iii and O4—H1O4···O1v hydrogen bonds (symmetry code in Table 1), to generate an array of six hydrogen bonds with the rings having the graph-set notations of R32(8), R22(8), R42(8), R22(8) and R32(8). The hydrogen glutarate anion self-assemble via O4—H1O4···O1 hydrogen bonds to form a one-dimensional supramolecular zigzag infinite chain, with the graph-set notation C(8); this is shown in Fig. 2. This type of head-to-tail fashion of hydrogen glutarate ions has also been observed in the crystal structure of pyrimethamine hydrogen glutarate (Stanley et al., 2002). The inversion-centre-related to the 2,6-diamino-4-chloropyrimidinium cations are also base-paired via N2—H2N2···N3ii hydrogen bonds involving the unprotonated pyrimidine N atom and the 2-amino group (symmetry code in Table 1). This type of base pairing, also with an R22(8) motif, has been observed in many diaminopyrimidiniumcarboxylate salts (Thanigaimani & Muthiah, 2010). These ring motifs extend to give a sheet parallel to (101) plane as shown in Fig 3.