Piperazinediium pyridine-2,5-dicarboxyl­ate dihydrate

In the title compound, C₄H₁₂N₂²⁺·C₇H₃NO₄²⁻·2H₂O, inter­molecular N—H...O and O—H...O hydrogen bonds and C—H...π inter­actions between piperazinediium and the aromatic ring of pyridine-2,5-dicarboxyl­ate are responsible for extending the structure into a three-dimensional supra­molecular network.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.038
• wR factor = 0.114
• Data-to-parameter ratio = 17.7

checkCIF/PLATON results

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PLAT154_ALERT_1_C The su's on the Cell Angles are Equal  (x 10000)        200 Deg.
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              C7 H3 N O4

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S1. Comment

Proton transfer is highly important in physics, chemistry and biochemistry. In order to develop new types of proton transfer compounds and hydrogen bonding systems, our research group has already synthesized proton transfer compounds with different proton donors and acceptors (Aghabozorg et al., 2006; Moghimi et al., 2005; Sheshmani et al., 2006). We herein report the crystal structure of the title compound, (I).

The molecule of the title compound, (I), contains one cation, one anion and also two water molecules (Fig. 1). The bond lengths and angles are within normal ranges (Allen et al., 1987). The piperazine ring: A (N2/N3/C8—C11) is not planar, having total puckering amplitude, Q_T of 1.104 (3) Å and chair conformation [φ = -151.67 (4)°, θ = 122.13 (3)°] (Cremer & Pople, 1975).

In the title compound, protons from one carboxylic acid unit are transferred to N atoms of the piperazine. The non-covalent interactions have an important role in self-association of the crystal system. As can be seen from the packing diagram (Fig. 2), the intermolecular N—H···O and O—H···O hydrogen bonds (Table 1) and C—H···π interactions between piperazinediium and aromatic ring of pyridine-2,5-dicarboxylate (Fig. 3) are responsible for extending the structure into three dimension resulting in a supramolecular network.

Related literature

For general backgroud, see: Aghabozorg et al. (2006); Moghimi et al. (2005); Sheshmani et al. (2006); Allen et al. (1987); Cremer & Pople (1975).

S2. Experimental

The title compound was synthesized by a reaction between pyridine-2,5-dicarboxylic acid (2,5-pydcH₂) and piperazine (pipz) in a 1:1 molar ratio. A solution of pipz (430 mg, 5 mmol) in tetrahydrofuran (10 ml) was added to a solution of 2,5-pydcH₂ (835 mg, 5 mmol) in tetrahydrofuran (10 ml). The resulting powder was dissolved in water to give colorless crystals of (I) (yield; 80%).

S3. Refinement

H atoms were positioned geometrically, with O—H = 0.82 Å (for OH₂), N—H = 0.87 Å (for NH₂) and C—H = 0.95 and 0.99 Å for aromatic and methylene H, respectively, and constrained to ride on their parent atoms, with U_iso(H) = 1.2U_eq(C,O,N).

Computing details

Data collection: APEXII (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2005); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A packing diagram for (I). Hydrogen bonds are shown as dashed lines.
	Fig. 3. Intermolecular C—H···π interaction between piperazinediium and aromatic ring of pyridine-2,5-dicarboxylate.

Piperazinediium pyridine-2,5-dicarboxylate dihydrate

Crystal data

C4H12N2^2+·C7H3NO4^2^−·2H2O	Z = 2
Mr = 289.29	F(000) = 308
Triclinic, P1	Dx = 1.432 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.0673 (6) Å	Cell parameters from 189 reflections
b = 9.9909 (9) Å	θ = 3–28°
c = 11.2827 (10) Å	µ = 0.12 mm^−1
α = 64.181 (2)°	T = 100 K
β = 77.479 (2)°	Prism, colorless
γ = 69.794 (2)°	0.24 × 0.22 × 0.19 mm
V = 670.92 (10) Å^3

Data collection

Bruker APEXII CCD area-detector diffractometer	3200 independent reflections
Radiation source: fine-focus sealed tube	2716 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
ω scans	θmax = 28.0°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −9→9
Tmin = 0.971, Tmax = 0.976	k = −13→13
6675 measured reflections	l = −14→14

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.038	Hydrogen site location: mixed
wR(F^2) = 0.114	H-atom parameters constrained
S = 0.99	w = 1/[σ^2(Fo^2) + (0.0683P)^2 + 0.2024P] where P = (Fo^2 + 2Fc^2)/3
3200 reflections	(Δ/σ)max < 0.001
181 parameters	Δρmax = 0.41 e Å^−3
0 restraints	Δρmin = −0.31 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.72069 (13)	0.42146 (11)	0.10061 (9)	0.0179 (2)
O2	0.68360 (13)	0.35887 (10)	0.31757 (9)	0.0172 (2)
O3	1.71752 (12)	−0.03466 (10)	0.33147 (8)	0.0153 (2)
O4	1.74763 (13)	0.08585 (10)	0.11263 (9)	0.0181 (2)
N1	1.33832 (15)	0.21315 (12)	0.10751 (10)	0.0139 (2)
C1	1.13793 (18)	0.27830 (14)	0.10828 (12)	0.0138 (2)
H1A	1.0800	0.3353	0.0257	0.017*
C2	1.00909 (17)	0.26795 (13)	0.22219 (12)	0.0122 (2)
C3	1.09484 (18)	0.18307 (14)	0.34258 (12)	0.0140 (2)
H3A	1.0123	0.1716	0.4230	0.017*
C4	1.30236 (18)	0.11520 (13)	0.34412 (12)	0.0138 (2)
H4A	1.3640	0.0576	0.4254	0.017*
C5	1.41866 (17)	0.13292 (13)	0.22462 (12)	0.0119 (2)
C6	0.78624 (17)	0.35448 (13)	0.21273 (12)	0.0124 (2)
C7	1.64623 (17)	0.05751 (13)	0.22069 (12)	0.0125 (2)
N2	0.92925 (15)	0.22547 (12)	0.71808 (10)	0.0131 (2)
H2NA	1.0383	0.1590	0.7023	0.016*
H2NB	0.9062	0.3013	0.6413	0.016*
N3	0.62060 (14)	0.34644 (11)	0.88677 (10)	0.0125 (2)
H3NA	0.5147	0.4194	0.8957	0.015*
H3NB	0.6435	0.2692	0.9629	0.015*
C8	0.76465 (18)	0.15153 (14)	0.78825 (12)	0.0151 (2)
H8A	0.8089	0.0667	0.8736	0.018*
H8B	0.7345	0.1062	0.7345	0.018*
C9	0.57630 (18)	0.27015 (14)	0.81250 (12)	0.0153 (2)
H9A	0.5247	0.3495	0.7269	0.018*
H9B	0.4702	0.2186	0.8635	0.018*
C10	0.78693 (17)	0.41821 (13)	0.81741 (11)	0.0132 (2)
H10A	0.8168	0.4641	0.8708	0.016*
H10B	0.7448	0.5023	0.7313	0.016*
C11	0.97483 (17)	0.29762 (14)	0.79543 (12)	0.0143 (2)
H11A	1.0839	0.3469	0.7470	0.017*
H11B	1.0221	0.2168	0.8816	0.017*
O1S	0.82858 (14)	0.44226 (10)	0.47339 (9)	0.0197 (2)
H1SA	0.7424	0.5214	0.4750	0.024*
H1SB	0.7827	0.4028	0.4401	0.024*
O2S	0.56303 (15)	0.71798 (11)	0.45834 (9)	0.0232 (2)
H2SB	0.4951	0.7101	0.5286	0.028*
H2SA	0.5919	0.7966	0.4441	0.028*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0134 (4)	0.0224 (4)	0.0144 (4)	0.0020 (3)	−0.0028 (3)	−0.0087 (4)
O2	0.0124 (4)	0.0223 (5)	0.0148 (4)	−0.0014 (3)	0.0009 (3)	−0.0092 (4)
O3	0.0118 (4)	0.0162 (4)	0.0132 (4)	0.0003 (3)	−0.0021 (3)	−0.0045 (3)
O4	0.0127 (4)	0.0191 (4)	0.0142 (4)	−0.0003 (3)	0.0009 (3)	−0.0032 (3)
N1	0.0117 (5)	0.0146 (5)	0.0127 (5)	−0.0017 (4)	−0.0007 (4)	−0.0047 (4)
C1	0.0128 (5)	0.0148 (5)	0.0125 (6)	−0.0013 (4)	−0.0025 (4)	−0.0055 (4)
C2	0.0106 (5)	0.0118 (5)	0.0146 (6)	−0.0017 (4)	−0.0007 (4)	−0.0069 (4)
C3	0.0142 (6)	0.0150 (5)	0.0117 (5)	−0.0028 (4)	0.0012 (4)	−0.0065 (4)
C4	0.0141 (6)	0.0135 (5)	0.0122 (5)	−0.0004 (4)	−0.0033 (4)	−0.0053 (4)
C5	0.0110 (5)	0.0107 (5)	0.0140 (5)	−0.0017 (4)	−0.0009 (4)	−0.0059 (4)
C6	0.0114 (5)	0.0114 (5)	0.0149 (6)	−0.0022 (4)	−0.0009 (4)	−0.0065 (4)
C7	0.0114 (5)	0.0105 (5)	0.0153 (6)	−0.0017 (4)	−0.0011 (4)	−0.0058 (4)
N2	0.0118 (5)	0.0139 (5)	0.0111 (5)	−0.0003 (4)	−0.0004 (4)	−0.0055 (4)
N3	0.0109 (5)	0.0139 (5)	0.0109 (5)	−0.0014 (4)	−0.0004 (4)	−0.0052 (4)
C8	0.0146 (5)	0.0141 (5)	0.0177 (6)	−0.0030 (4)	−0.0008 (4)	−0.0083 (5)
C9	0.0113 (5)	0.0189 (6)	0.0180 (6)	−0.0034 (4)	−0.0014 (4)	−0.0098 (5)
C10	0.0144 (5)	0.0128 (5)	0.0119 (5)	−0.0038 (4)	−0.0001 (4)	−0.0048 (4)
C11	0.0115 (5)	0.0181 (6)	0.0142 (6)	−0.0044 (4)	0.0004 (4)	−0.0075 (5)
O1S	0.0254 (5)	0.0179 (4)	0.0166 (5)	−0.0043 (4)	−0.0047 (4)	−0.0075 (4)
O2S	0.0313 (5)	0.0206 (5)	0.0188 (5)	−0.0112 (4)	0.0070 (4)	−0.0098 (4)

Geometric parameters (Å, º)

O1—C6	1.2511 (15)	N3—C10	1.4843 (15)
O2—C6	1.2563 (15)	N3—C9	1.4887 (15)
O3—C7	1.2705 (15)	N3—H3NA	0.8698
O4—C7	1.2413 (15)	N3—H3NB	0.8695
N1—C1	1.3387 (15)	C8—C9	1.5120 (16)
N1—C5	1.3413 (15)	C8—H8A	0.9900
C1—C2	1.3905 (16)	C8—H8B	0.9900
C1—H1A	0.9500	C9—H9A	0.9900
C2—C3	1.3892 (16)	C9—H9B	0.9900
C2—C6	1.5137 (15)	C10—C11	1.5128 (16)
C3—C4	1.3874 (16)	C10—H10A	0.9900
C3—H3A	0.9500	C10—H10B	0.9900
C4—C5	1.3918 (16)	C11—H11A	0.9900
C4—H4A	0.9500	C11—H11B	0.9900
C5—C7	1.5223 (16)	O1S—H1SA	0.8197
N2—C8	1.4868 (16)	O1S—H1SB	0.8197
N2—C11	1.4885 (15)	O2S—H2SB	0.8199
N2—H2NA	0.8699	O2S—H2SA	0.8195
N2—H2NB	0.8695
C1—N1—C5	117.45 (10)	C9—N3—H3NA	110.7
N1—C1—C2	124.22 (11)	C10—N3—H3NB	117.0
N1—C1—H1A	117.9	C9—N3—H3NB	100.3
C2—C1—H1A	117.9	H3NA—N3—H3NB	109.6
C3—C2—C1	117.48 (11)	N2—C8—C9	110.20 (10)
C3—C2—C6	122.09 (10)	N2—C8—H8A	109.6
C1—C2—C6	120.33 (10)	C9—C8—H8A	109.6
C4—C3—C2	119.28 (11)	N2—C8—H8B	109.6
C4—C3—H3A	120.4	C9—C8—H8B	109.6
C2—C3—H3A	120.4	H8A—C8—H8B	108.1
C3—C4—C5	118.90 (11)	N3—C9—C8	110.65 (9)
C3—C4—H4A	120.6	N3—C9—H9A	109.5
C5—C4—H4A	120.6	C8—C9—H9A	109.5
N1—C5—C4	122.66 (11)	N3—C9—H9B	109.5
N1—C5—C7	116.24 (10)	C8—C9—H9B	109.5
C4—C5—C7	121.08 (10)	H9A—C9—H9B	108.1
O1—C6—O2	125.15 (11)	N3—C10—C11	110.20 (9)
O1—C6—C2	117.55 (10)	N3—C10—H10A	109.6
O2—C6—C2	117.22 (10)	C11—C10—H10A	109.6
O4—C7—O3	124.71 (11)	N3—C10—H10B	109.6
O4—C7—C5	119.37 (10)	C11—C10—H10B	109.6
O3—C7—C5	115.90 (10)	H10A—C10—H10B	108.1
C8—N2—C11	110.78 (9)	N2—C11—C10	109.79 (9)
C8—N2—H2NA	111.4	N2—C11—H11A	109.7
C11—N2—H2NA	110.0	C10—C11—H11A	109.7
C8—N2—H2NB	117.1	N2—C11—H11B	109.7
C11—N2—H2NB	103.1	C10—C11—H11B	109.7
H2NA—N2—H2NB	103.9	H11A—C11—H11B	108.2
C10—N3—C9	111.45 (9)	H1SA—O1S—H1SB	108.3
C10—N3—H3NA	107.6	H2SB—O2S—H2SA	98.1
C5—N1—C1—C2	0.01 (18)	C3—C2—C6—O2	6.44 (17)
N1—C1—C2—C3	−0.63 (18)	C1—C2—C6—O2	−169.99 (11)
N1—C1—C2—C6	175.95 (11)	N1—C5—C7—O4	7.27 (16)
C1—C2—C3—C4	0.93 (17)	C4—C5—C7—O4	−174.20 (11)
C6—C2—C3—C4	−175.59 (11)	N1—C5—C7—O3	−171.12 (10)
C2—C3—C4—C5	−0.64 (18)	C4—C5—C7—O3	7.41 (16)
C1—N1—C5—C4	0.32 (17)	C11—N2—C8—C9	58.08 (12)
C1—N1—C5—C7	178.83 (10)	C10—N3—C9—C8	56.11 (12)
C3—C4—C5—N1	0.00 (18)	N2—C8—C9—N3	−56.11 (13)
C3—C4—C5—C7	−178.44 (10)	C9—N3—C10—C11	−56.94 (12)
C3—C2—C6—O1	−176.57 (11)	C8—N2—C11—C10	−58.93 (12)
C1—C2—C6—O1	7.01 (17)	N3—C10—C11—N2	57.86 (12)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2NA···O3^i	0.87	1.82	2.686 (2)	173
N2—H2NB···O1S	0.87	1.86	2.719 (1)	169
N3—H3NA···O1^ii	0.87	1.87	2.736 (2)	174
N3—H3NB···O4^iii	0.87	1.91	2.770 (1)	168
O1S—H1SA···O2S	0.82	1.89	2.701 (2)	172
O1S—H1SB···O2	0.82	1.94	2.735 (1)	164
O2S—H2SB···O2^ii	0.82	1.92	2.709 (1)	161
O2S—H2SA···O3^iv	0.82	1.98	2.730 (2)	152

Symmetry codes: (i) −x+3, −y, −z+1; (ii) −x+1, −y+1, −z+1; (iii) x−1, y, z+1; (iv) x−1, y+1, z.