organic compounds
Piperazine-1,4-diium pyridine-2,3-dicarboxylate methanol monosolvate†
aDepartment of Chemistry, Iran University of Science and Technology, Tehran, Iran, and bDepartment of Chemistry, Faculty of Science, University of Kurdistan, Sanandaj, Iran
*Correspondence e-mail: mghadermazi@yahoo.com
The title solvated molecular salt, C4H12N22+·C7H3NO42−·CH3OH or (pipzH2)(py-2,3-dc)·MeOH, was prepared by the reaction of pyridine-2,3-dicarboxylic acid (py-2,3-dcH2) and piperazine (pipz) in methanol (MeOH) as solvent. One of the two carboxylate groups of the acid fragment is nearly perpendicular to the pyridine ring and the other is almost in its plane [C—C—C—O torsion angles = −85.50 (11) and 88.07 (11)° and N—C—C—O torsion angles = −176.31 (8) and 5.41 (13)°]. In the crystal, the components are linked by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds, generating a three-dimensional network.
Related literature
For similar ion pairs, see: Aghabozorg, Manteghi & Ghadermazi (2008); Aghabozorg, Manteghi & Sheshmani (2008). For related metal complexes, see: Barszcz et al. (2010); Li & Li (2004).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: APEX2 (Bruker, 2005); cell SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536811012384/om2416sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811012384/om2416Isup2.hkl
The title compound was synthesized via reaction of 1670 mg (10 mmol) pyridine-2,3-dicarboxylic acid with 860 mg (10 mmol) piperazine in a methanol solution (60 ml). The obtained white precipitate was filtered out and dissolved in water to recrystallize. Colorless crystals of the title compound were obtained after 14 days.
The H(N) and H(O) atoms were found from a difference Fourier map. The H(C) atom positions were calculated. All the hydrogen atoms were refined with isotropic displacement paramaters using a riding model with the Uiso(H) parameters equal to 1.2 times the equivalent isotropic thermal parameter of the bonded C(CH2) or N(NH2) or 1.5 times that of C(CH3) and O(H2O). Distances were 0.90 Å for N-H, 0.85 Å for O-H, and 0.95 - 0.99 Å for C-H.
Data collection: APEX2 (Bruker, 2005); cell
SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. The molecular structure of (pipzH2)(py-2,3-dc).MeOH | |
Fig. 2. The C–H···π stacking between C12–H1A of methanol and N1/C1-C5 ring of py-2,3-dc. |
C4H12N22+·C7H3NO42−·CH4O | F(000) = 608 |
Mr = 285.30 | Dx = 1.396 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 7483 reflections |
a = 8.2541 (6) Å | θ = 2.3–28.1° |
b = 11.8988 (8) Å | µ = 0.11 mm−1 |
c = 13.8197 (9) Å | T = 100 K |
β = 90.288 (2)° | Prism, colourless |
V = 1357.27 (16) Å3 | 0.25 × 0.20 × 0.10 mm |
Z = 4 |
Bruker SMART APEXII diffractometer | 3189 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.023 |
Graphite monochromator | θmax = 29.0°, θmin = 2.3° |
Detector resolution: 8.3 pixels mm-1 | h = −11→11 |
ϕ and ω scans | k = −16→16 |
16044 measured reflections | l = −18→18 |
3579 independent reflections |
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)] = 0.034 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.085 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.035P)2 + 0.650P] where P = (Fo2 + 2Fc2)/3 |
3579 reflections | (Δ/σ)max = 0.001 |
182 parameters | Δρmax = 0.42 e Å−3 |
0 restraints | Δρmin = −0.21 e Å−3 |
C4H12N22+·C7H3NO42−·CH4O | V = 1357.27 (16) Å3 |
Mr = 285.30 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 8.2541 (6) Å | µ = 0.11 mm−1 |
b = 11.8988 (8) Å | T = 100 K |
c = 13.8197 (9) Å | 0.25 × 0.20 × 0.10 mm |
β = 90.288 (2)° |
Bruker SMART APEXII diffractometer | 3189 reflections with I > 2σ(I) |
16044 measured reflections | Rint = 0.023 |
3579 independent reflections |
R[F2 > 2σ(F2)] = 0.034 | 0 restraints |
wR(F2) = 0.085 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.42 e Å−3 |
3579 reflections | Δρmin = −0.21 e Å−3 |
182 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 | ||
O1 | 0.16285 (8) | 0.76486 (6) | 0.03344 (5) | 0.01401 (15) | |
O2 | 0.21626 (9) | 0.91599 (6) | 0.12414 (6) | 0.01918 (16) | |
O3 | −0.13943 (9) | 0.61040 (6) | 0.03291 (5) | 0.01666 (16) | |
O4 | −0.11791 (9) | 0.70279 (6) | −0.10648 (5) | 0.01627 (15) | |
N1 | −0.09833 (10) | 0.97903 (7) | 0.11968 (6) | 0.01339 (17) | |
N2 | 0.17152 (10) | 1.11819 (7) | 0.21302 (6) | 0.01264 (16) | |
H2A | 0.1410 | 1.1746 | 0.1735 | 0.015* | |
H2B | 0.1538 | 1.0523 | 0.1828 | 0.015* | |
N3 | 0.31476 (10) | 1.05117 (7) | 0.39424 (6) | 0.01304 (16) | |
H3A | 0.3349 | 1.1189 | 0.4206 | 0.016* | |
H3B | 0.3473 | 0.9987 | 0.4371 | 0.016* | |
C1 | −0.05754 (11) | 0.88142 (8) | 0.07675 (6) | 0.01078 (17) | |
C2 | −0.17210 (11) | 0.80866 (8) | 0.03586 (7) | 0.01165 (18) | |
C3 | −0.33567 (12) | 0.83780 (9) | 0.04316 (7) | 0.01506 (19) | |
H3 | −0.4169 | 0.7896 | 0.0175 | 0.018* | |
C4 | −0.37860 (12) | 0.93756 (9) | 0.08809 (7) | 0.0166 (2) | |
H4 | −0.4891 | 0.9585 | 0.0943 | 0.020* | |
C5 | −0.25545 (12) | 1.00615 (9) | 0.12379 (7) | 0.01563 (19) | |
H5 | −0.2845 | 1.0758 | 0.1525 | 0.019* | |
C6 | 0.12243 (11) | 0.85332 (8) | 0.07816 (7) | 0.01183 (18) | |
C7 | −0.13540 (11) | 0.69936 (8) | −0.01603 (7) | 0.01243 (18) | |
C8 | 0.07828 (12) | 1.12692 (9) | 0.30451 (7) | 0.01538 (19) | |
H8A | −0.0383 | 1.1149 | 0.2908 | 0.018* | |
H8B | 0.0914 | 1.2032 | 0.3320 | 0.018* | |
C9 | 0.34843 (12) | 1.13038 (8) | 0.23146 (7) | 0.01367 (18) | |
H9A | 0.3709 | 1.2059 | 0.2584 | 0.016* | |
H9B | 0.4080 | 1.1231 | 0.1698 | 0.016* | |
C10 | 0.40670 (12) | 1.04139 (8) | 0.30194 (7) | 0.01438 (19) | |
H10A | 0.3901 | 0.9658 | 0.2737 | 0.017* | |
H10B | 0.5239 | 1.0513 | 0.3148 | 0.017* | |
C11 | 0.13684 (12) | 1.04015 (9) | 0.37760 (7) | 0.0162 (2) | |
H11A | 0.0790 | 1.0508 | 0.4395 | 0.019* | |
H11B | 0.1121 | 0.9637 | 0.3533 | 0.019* | |
O5 | 0.39165 (9) | 0.71135 (8) | −0.09625 (6) | 0.02485 (19) | |
H5A | 0.3255 | 0.7344 | −0.0537 | 0.037* | |
C12 | 0.29401 (15) | 0.65794 (12) | −0.16692 (9) | 0.0302 (3) | |
H1A | 0.3427 | 0.6679 | −0.2309 | 0.045* | |
H1B | 0.1855 | 0.6913 | −0.1667 | 0.045* | |
H1C | 0.2861 | 0.5776 | −0.1522 | 0.045* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0156 (3) | 0.0103 (3) | 0.0162 (3) | 0.0017 (2) | 0.0019 (3) | −0.0011 (3) |
O2 | 0.0139 (3) | 0.0188 (4) | 0.0248 (4) | 0.0001 (3) | −0.0031 (3) | −0.0083 (3) |
O3 | 0.0236 (4) | 0.0110 (3) | 0.0153 (3) | −0.0009 (3) | −0.0041 (3) | 0.0011 (3) |
O4 | 0.0233 (4) | 0.0130 (3) | 0.0124 (3) | 0.0028 (3) | −0.0019 (3) | −0.0007 (3) |
N1 | 0.0154 (4) | 0.0117 (4) | 0.0130 (4) | 0.0005 (3) | 0.0011 (3) | −0.0010 (3) |
N2 | 0.0152 (4) | 0.0111 (4) | 0.0116 (4) | 0.0003 (3) | −0.0022 (3) | 0.0000 (3) |
N3 | 0.0168 (4) | 0.0105 (4) | 0.0118 (4) | −0.0007 (3) | −0.0025 (3) | 0.0007 (3) |
C1 | 0.0128 (4) | 0.0103 (4) | 0.0093 (4) | 0.0003 (3) | 0.0007 (3) | 0.0009 (3) |
C2 | 0.0143 (4) | 0.0109 (4) | 0.0097 (4) | 0.0003 (3) | −0.0006 (3) | 0.0008 (3) |
C3 | 0.0135 (4) | 0.0173 (5) | 0.0144 (4) | −0.0005 (3) | −0.0013 (3) | −0.0005 (4) |
C4 | 0.0134 (4) | 0.0201 (5) | 0.0163 (4) | 0.0037 (4) | 0.0002 (3) | 0.0002 (4) |
C5 | 0.0181 (5) | 0.0136 (4) | 0.0152 (4) | 0.0032 (4) | 0.0023 (3) | −0.0016 (3) |
C6 | 0.0132 (4) | 0.0111 (4) | 0.0112 (4) | 0.0005 (3) | 0.0006 (3) | 0.0015 (3) |
C7 | 0.0117 (4) | 0.0115 (4) | 0.0141 (4) | 0.0001 (3) | −0.0035 (3) | −0.0015 (3) |
C8 | 0.0142 (4) | 0.0172 (5) | 0.0148 (4) | 0.0009 (4) | 0.0003 (3) | 0.0002 (4) |
C9 | 0.0142 (4) | 0.0137 (4) | 0.0132 (4) | −0.0004 (3) | −0.0002 (3) | 0.0007 (3) |
C10 | 0.0154 (4) | 0.0146 (4) | 0.0130 (4) | 0.0021 (3) | −0.0011 (3) | −0.0002 (3) |
C11 | 0.0160 (5) | 0.0168 (5) | 0.0159 (4) | −0.0040 (4) | −0.0006 (3) | 0.0028 (4) |
O5 | 0.0159 (4) | 0.0345 (5) | 0.0242 (4) | −0.0027 (3) | 0.0035 (3) | −0.0117 (3) |
C12 | 0.0239 (6) | 0.0398 (7) | 0.0269 (6) | −0.0016 (5) | 0.0002 (5) | −0.0160 (5) |
O1—C6 | 1.2662 (12) | C3—H3 | 0.9500 |
O2—C6 | 1.2469 (12) | C4—C5 | 1.3920 (14) |
O3—C7 | 1.2566 (12) | C4—H4 | 0.9500 |
O4—C7 | 1.2597 (12) | C5—H5 | 0.9500 |
N1—C5 | 1.3379 (13) | C8—C11 | 1.5215 (14) |
N1—C1 | 1.3477 (12) | C8—H8A | 0.9900 |
N2—C8 | 1.4871 (12) | C8—H8B | 0.9900 |
N2—C9 | 1.4881 (12) | C9—C10 | 1.5155 (13) |
N2—H2A | 0.9001 | C9—H9A | 0.9900 |
N2—H2B | 0.9001 | C9—H9B | 0.9900 |
N3—C11 | 1.4911 (13) | C10—H10A | 0.9900 |
N3—C10 | 1.4920 (12) | C10—H10B | 0.9900 |
N3—H3A | 0.9000 | C11—H11A | 0.9900 |
N3—H3B | 0.9001 | C11—H11B | 0.9900 |
C1—C2 | 1.3992 (13) | O5—C12 | 1.4139 (14) |
C1—C6 | 1.5227 (13) | O5—H5A | 0.8500 |
C2—C3 | 1.3981 (13) | C12—H1A | 0.9800 |
C2—C7 | 1.5164 (13) | C12—H1B | 0.9800 |
C3—C4 | 1.3864 (14) | C12—H1C | 0.9800 |
C5—N1—C1 | 118.09 (8) | O4—C7—C2 | 117.75 (8) |
C8—N2—C9 | 111.05 (7) | N2—C8—C11 | 110.67 (8) |
C8—N2—H2A | 108.6 | N2—C8—H8A | 109.5 |
C9—N2—H2A | 107.6 | C11—C8—H8A | 109.5 |
C8—N2—H2B | 111.9 | N2—C8—H8B | 109.5 |
C9—N2—H2B | 108.8 | C11—C8—H8B | 109.5 |
H2A—N2—H2B | 108.9 | H8A—C8—H8B | 108.1 |
C11—N3—C10 | 111.47 (7) | N2—C9—C10 | 110.48 (8) |
C11—N3—H3A | 108.7 | N2—C9—H9A | 109.6 |
C10—N3—H3A | 108.9 | C10—C9—H9A | 109.6 |
C11—N3—H3B | 109.3 | N2—C9—H9B | 109.6 |
C10—N3—H3B | 110.9 | C10—C9—H9B | 109.6 |
H3A—N3—H3B | 107.5 | H9A—C9—H9B | 108.1 |
N1—C1—C2 | 122.77 (9) | N3—C10—C9 | 109.50 (8) |
N1—C1—C6 | 115.44 (8) | N3—C10—H10A | 109.8 |
C2—C1—C6 | 121.77 (8) | C9—C10—H10A | 109.8 |
C3—C2—C1 | 117.92 (9) | N3—C10—H10B | 109.8 |
C3—C2—C7 | 116.24 (8) | C9—C10—H10B | 109.8 |
C1—C2—C7 | 125.84 (8) | H10A—C10—H10B | 108.2 |
C4—C3—C2 | 119.59 (9) | N3—C11—C8 | 110.61 (8) |
C4—C3—H3 | 120.2 | N3—C11—H11A | 109.5 |
C2—C3—H3 | 120.2 | C8—C11—H11A | 109.5 |
C3—C4—C5 | 118.22 (9) | N3—C11—H11B | 109.5 |
C3—C4—H4 | 120.9 | C8—C11—H11B | 109.5 |
C5—C4—H4 | 120.9 | H11A—C11—H11B | 108.1 |
N1—C5—C4 | 123.36 (9) | C12—O5—H5A | 104.9 |
N1—C5—H5 | 118.3 | O5—C12—H1A | 109.5 |
C4—C5—H5 | 118.3 | O5—C12—H1B | 109.5 |
O2—C6—O1 | 125.55 (9) | H1A—C12—H1B | 109.5 |
O2—C6—C1 | 118.59 (8) | O5—C12—H1C | 109.5 |
O1—C6—C1 | 115.84 (8) | H1A—C12—H1C | 109.5 |
O3—C7—O4 | 124.39 (9) | H1B—C12—H1C | 109.5 |
O3—C7—C2 | 117.52 (8) | ||
C5—N1—C1—C2 | 0.66 (14) | N1—C1—C6—O1 | −176.31 (8) |
C5—N1—C1—C6 | −177.60 (8) | C2—C1—C6—O1 | 5.41 (13) |
N1—C1—C2—C3 | −2.12 (14) | C3—C2—C7—O3 | −85.50 (11) |
C6—C1—C2—C3 | 176.03 (8) | C1—C2—C7—O3 | 94.23 (12) |
N1—C1—C2—C7 | 178.16 (9) | C3—C2—C7—O4 | 88.07 (11) |
C6—C1—C2—C7 | −3.69 (14) | C1—C2—C7—O4 | −92.20 (12) |
C1—C2—C3—C4 | 1.40 (14) | C9—N2—C8—C11 | −56.46 (10) |
C7—C2—C3—C4 | −178.84 (9) | C8—N2—C9—C10 | 58.30 (10) |
C2—C3—C4—C5 | 0.61 (15) | C11—N3—C10—C9 | 57.68 (10) |
C1—N1—C5—C4 | 1.56 (15) | N2—C9—C10—N3 | −58.17 (10) |
C3—C4—C5—N1 | −2.20 (15) | C10—N3—C11—C8 | −56.39 (11) |
N1—C1—C6—O2 | 5.41 (13) | N2—C8—C11—N3 | 55.14 (11) |
C2—C1—C6—O2 | −172.86 (9) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2A···O4i | 0.90 | 1.74 | 2.6257 (11) | 168 |
N2—H2B···O2 | 0.90 | 1.89 | 2.7274 (11) | 155 |
N3—H3A···O1ii | 0.90 | 1.85 | 2.7379 (11) | 169 |
N3—H3B···O3iii | 0.90 | 1.86 | 2.7393 (11) | 166 |
O5—H5A···O1 | 0.85 | 1.84 | 2.6867 (10) | 171 |
C3—H3···O5iv | 0.95 | 2.41 | 3.3163 (13) | 159 |
Symmetry codes: (i) −x, −y+2, −z; (ii) −x+1/2, y+1/2, −z+1/2; (iii) x+1/2, −y+3/2, z+1/2; (iv) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C4H12N22+·C7H3NO42−·CH4O |
Mr | 285.30 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 100 |
a, b, c (Å) | 8.2541 (6), 11.8988 (8), 13.8197 (9) |
β (°) | 90.288 (2) |
V (Å3) | 1357.27 (16) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.11 |
Crystal size (mm) | 0.25 × 0.20 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART APEXII diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 16044, 3579, 3189 |
Rint | 0.023 |
(sin θ/λ)max (Å−1) | 0.682 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.034, 0.085, 1.03 |
No. of reflections | 3579 |
No. of parameters | 182 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.42, −0.21 |
Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and Mercury (Macrae et al., 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2A···O4i | 0.90 | 1.74 | 2.6257 (11) | 168 |
N2—H2B···O2 | 0.90 | 1.89 | 2.7274 (11) | 155 |
N3—H3A···O1ii | 0.90 | 1.85 | 2.7379 (11) | 169 |
N3—H3B···O3iii | 0.90 | 1.86 | 2.7393 (11) | 166 |
O5—H5A···O1 | 0.85 | 1.84 | 2.6867 (10) | 171 |
C3—H3···O5iv | 0.95 | 2.41 | 3.3163 (13) | 159 |
Symmetry codes: (i) −x, −y+2, −z; (ii) −x+1/2, y+1/2, −z+1/2; (iii) x+1/2, −y+3/2, z+1/2; (iv) x−1, y, z. |
Footnotes
†In memory of our great professor, Dr Hossein Aghabozorg, who passed away recently.
Acknowledgements
We acknowledge financial support of this work by the Iran University of Science and Technology and the University of Kurdistan.
References
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Pyridine-2,3-dicarboxylic acid is remarkably attractive for its flexible and variable coordination modes to construct polymeric architecture. It can act as monodicarboxylate chelating anion, or tridentate coordinating anion with acid hydrogen on nitrogen and doubly deprotonated, tridentate dicarboxylate anion (py-2,3-dc) and even in Mn(II) complexes as tetradenatate and pentadentate ligands (Barszcz et al., 2010; Li & Li, 2004). Preparation of ion pairs with the acid increases the chance of its coordination to metals. Therefore, in our work to obtain proton transfer ion pairs, we have reviewed many ion pairs and their metal complexes (Aghabozorg, Manteghi & Sheshmani, 2008). Also, we have reported a similar ion pair formulated as (pipzH2)(pydcH)2, (Aghabozorg, Manteghi & Ghadermazi, 2008). The title structure, as shown in Fig. 1, has an asymmetric unit constructed by (pipzH2)2+ and (py-2,3-dc)2– and a neutral methanol molecule with two hydrogen bonds. There are varieties of other strong and weak hydrogen bonds in the structure, shown in Table 1. Also, a C–O···π stacking, between C6–O2 and N1/C1-C5 ring (-x, -y + 2, -z) with the distance of 3.5240 (9) Å, and a C–H···π stacking, between C12–H1A and N1/C1-C5 ring (x +1/2, -y +3/2, z -1/2), with the distance of 2.791 (1) Å, shown in Fig. 2 are observed.