Hydrazinediium bis­(6-carboxy­pyridazine-3-carboxyl­ate) dihydrate

The triclinic unit cell of the title compound, N₂H₆²⁺·2C₆H₃N₂O₄^-·2H₂O, contains one doubly protonated hydrazine cation which lies on an inversion centre, two symmetry-related singly deprotonated 6-carboxy­pyridazine-3-carboxyl­ate anions and two symmetry-related solvent water mol­ecules. The anions inter­act via hydrogen bonds to form double ribbons which are bridged by hydrogen bonds donated by hydrazinediium cations and water molecules.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.040
• wR factor = 0.133
• Data-to-parameter ratio = 14.3

checkCIF/PLATON results

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Alert level C
PLAT041_ALERT_1_C Calc. and Rep. SumFormula Strings    Differ ....          ?
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT045_ALERT_1_C Calculated and Reported Z Differ by ............       2.00 Ratio
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.27
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal  (x 10000)       3000 Deg.
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.77 Ratio
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.47
PLAT353_ALERT_3_C Long    N-H Bond (0.87A)   N3     -   H52    ...       1.04 Ang.
PLAT355_ALERT_3_C Long    O-H Bond (0.82A)   O1     -   H1     ...       1.03 Ang.
PLAT417_ALERT_2_C Short Inter D-H..H-D       H52    ..  H62     ..       2.11 Ang.
PLAT432_ALERT_2_C Short Inter X...Y Contact  O2     ..  C8      ..       3.00 Ang.

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
  11 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

   6 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The structure of the title compound (I) is composed of one doubly-protonated hydrazine cation having its geometrical centre on an inversion centre at 1/2,0,0, two symmetry related singly-deprotonated pyridazine-3,6-dicarboxylate anions and a pair of symmetry related solvent water molecules. Fig.1 shows the asymetric unit with atom labelling scheme. Atoms forming the pyridazine ring are coplanar (r.m.s.0.057 Å). The carboxylate moiety (C7/O1/O2) makes an angle of 3.8 (1) ° with the pyridazine ring, while the (C8/O3/O4) group makes an angle of 1.1 (1) °. Bond lengths and bond angles within the title anion agree well with those reported in the structures of both modifications of the parent acid (Sueur et al., 1987, Starosta & Leciejewicz, 2004). A fairly strong hydrogen bond of 2.515 (2) Å is observed between the protonated O atom of the carboxylic group acting as a donor and the deprotonated carboxylate O atom in the adjacent anion giving rise to polyionic ribbons composed of pairs of anions (Fig. 2). The ribbons are bridged by weaker bonds in which the hydrazine cations and solvation water molecules are the donors and the anions' O atoms and hetero-ring N atoms act as acceptors.

Related literature

For the crystal structures of two polymorphs of the hydrazine adduct of pyrazole-3,5-dicarboxylic acid, see Kumar et al. (2007). Singly protonated hydrazine cations and di(aqua-O)bis(pyridazine-3,6-dicarboxylato-N,O) magnesium(II) anions have also been observed (Gryz et al., 2004).

For related literature, see: Starosta & Leciejewicz (2004); Sueur et al. (1987).

S2. Experimental

In the course of experiments aiming to obtain single crystals of a calcium complex with pyridazine-3,6-dicarboxylate ligand, single crystals of either the triclinic modification of the pyridazine-3,6-dicarboxylic acid dihydrate (Starosta & Leciejewicz, 2004) or of the title compound were found in the mass of polycrystalline material. The crystals of the title compound appeared when hydrazine was used to maintain the acidicity of the initial solution.

S3. Refinement

All H atoms were located in a difference map and refined with isotropic displacement parameters.

Computing details

Data collection: KM-4 Software (Kuma, 1996); cell refinement: KM-4 Software (Kuma, 1996); data reduction: DATAPROC (Kuma, 2001); 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: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. The asymmetric unit with atom labelling scheme and 50% probability displacement ellipsoids. The hydrazine cation is symmetry complete (symmetry code: (A) -x + 1, -y + 1, -z + 1).
	Fig. 2. Packing diagram of the structure of (I).

Hydrazinediium bis(6-carboxypyridazine-3-carboxylate) dihydrate

Crystal data

N2H6^2+·2C6H3N2O4^−·2H2O	Z = 1
Mr = 404.31	F(000) = 210
Triclinic, P1	Dx = 1.728 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.1727 (10) Å	Cell parameters from 25 reflections
b = 6.6257 (13) Å	θ = 6–15°
c = 12.271 (3) Å	µ = 0.15 mm^−1
α = 102.08 (3)°	T = 293 K
β = 93.92 (3)°	Rectangular plate, colourless
γ = 107.44 (3)°	0.16 × 0.08 × 0.07 mm
V = 388.47 (17) Å^3

Data collection

Kuma KM-4 four-circle diffractometer	Rint = 0.017
Radiation source: fine-focus sealed tube	θmax = 30.1°, θmin = 1.7°
Graphite monochromator	h = −7→0
profile data from ω/2θ scans	k = −8→9
2512 measured reflections	l = −17→17
2279 independent reflections	3 standard reflections every 200 reflections
1431 reflections with I > 2σ(I)	intensity decay: 3.7%

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.133	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ^2(Fo^2) + (0.092P)^2] where P = (Fo^2 + 2Fc^2)/3
2279 reflections	(Δ/σ)max < 0.001
159 parameters	Δρmax = 0.52 e Å^−3
0 restraints	Δρmin = −0.23 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 F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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
O2	0.0745 (3)	1.1260 (2)	0.19096 (9)	0.0301 (3)
O3	0.6795 (3)	0.37197 (19)	0.35261 (9)	0.0292 (3)
O4	0.7130 (3)	0.4033 (2)	0.17502 (10)	0.0319 (3)
O1	−0.0377 (3)	1.1253 (2)	0.36330 (10)	0.0315 (3)
N2	0.3236 (3)	0.8346 (2)	0.19854 (10)	0.0248 (3)
N1	0.4514 (3)	0.6882 (2)	0.19574 (10)	0.0261 (3)
C6	0.4853 (3)	0.6120 (2)	0.28600 (11)	0.0198 (3)
C3	0.2223 (3)	0.9032 (2)	0.29085 (11)	0.0191 (3)
C7	0.0773 (3)	1.0655 (2)	0.27720 (12)	0.0212 (3)
C4	0.2473 (3)	0.8274 (2)	0.38706 (12)	0.0238 (3)
C8	0.6396 (3)	0.4472 (2)	0.26852 (12)	0.0215 (3)
C5	0.3863 (4)	0.6784 (3)	0.38484 (12)	0.0250 (3)
O6	0.1862 (3)	0.3212 (2)	0.98874 (10)	0.0295 (3)
N3	0.3528 (3)	0.9661 (2)	0.99354 (11)	0.0233 (3)
H5	0.169 (4)	0.871 (3)	0.4510 (18)	0.031 (5)*
H6	0.411 (4)	0.628 (3)	0.4471 (19)	0.037 (6)*
H62	0.268 (6)	0.416 (5)	1.044 (2)	0.059 (8)*
H51	0.288 (5)	0.840 (4)	0.9317 (19)	0.038 (6)*
H61	0.223 (5)	0.395 (4)	0.927 (2)	0.045 (6)*
H53	0.307 (5)	0.924 (3)	1.0576 (18)	0.035 (5)*
H52	0.288 (5)	1.098 (4)	0.9885 (18)	0.036 (5)*
H1	−0.136 (8)	1.234 (6)	0.350 (3)	0.117 (14)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O2	0.0426 (8)	0.0379 (6)	0.0231 (5)	0.0268 (6)	0.0091 (5)	0.0143 (4)
O3	0.0400 (7)	0.0348 (6)	0.0259 (5)	0.0261 (5)	0.0095 (5)	0.0130 (4)
O4	0.0465 (8)	0.0369 (6)	0.0248 (5)	0.0295 (6)	0.0119 (5)	0.0082 (4)
O1	0.0459 (8)	0.0394 (7)	0.0263 (5)	0.0315 (6)	0.0165 (5)	0.0148 (5)
N2	0.0362 (8)	0.0282 (6)	0.0197 (5)	0.0208 (6)	0.0089 (5)	0.0098 (5)
N1	0.0382 (8)	0.0294 (7)	0.0215 (6)	0.0231 (6)	0.0105 (5)	0.0092 (5)
C6	0.0237 (7)	0.0200 (6)	0.0200 (6)	0.0123 (5)	0.0051 (5)	0.0055 (5)
C3	0.0225 (7)	0.0199 (6)	0.0184 (6)	0.0109 (5)	0.0044 (5)	0.0056 (5)
C7	0.0238 (7)	0.0222 (7)	0.0210 (6)	0.0119 (6)	0.0037 (5)	0.0053 (5)
C4	0.0339 (8)	0.0279 (7)	0.0179 (6)	0.0194 (6)	0.0084 (6)	0.0077 (5)
C8	0.0249 (8)	0.0202 (6)	0.0231 (6)	0.0124 (6)	0.0036 (5)	0.0058 (5)
C5	0.0373 (9)	0.0284 (7)	0.0190 (6)	0.0206 (7)	0.0081 (6)	0.0102 (5)
O6	0.0375 (7)	0.0290 (6)	0.0237 (6)	0.0128 (5)	0.0049 (5)	0.0070 (4)
N3	0.0225 (7)	0.0293 (7)	0.0220 (6)	0.0121 (5)	0.0057 (5)	0.0084 (5)

Geometric parameters (Å, º)

O2—C7	1.2082 (18)	C3—C7	1.5128 (18)
O3—C8	1.2666 (17)	C4—C5	1.382 (2)
O4—C8	1.2376 (18)	C4—H5	0.94 (2)
O1—C7	1.2956 (18)	C5—H6	0.91 (2)
O1—H1	1.03 (4)	O6—H62	0.81 (3)
N2—N1	1.3241 (17)	O6—H61	0.98 (3)
N2—C3	1.3313 (18)	N3—N3^i	1.440 (3)
N1—C6	1.3317 (17)	N3—H51	0.96 (2)
C6—C5	1.387 (2)	N3—H53	0.91 (2)
C6—C8	1.5236 (18)	N3—H52	1.04 (2)
C3—C4	1.3889 (19)
C7—O1—H1	111 (2)	C3—C4—H5	122.1 (13)
N1—N2—C3	120.23 (12)	O4—C8—O3	127.45 (13)
N2—N1—C6	120.34 (12)	O4—C8—C6	116.92 (12)
N1—C6—C5	122.08 (13)	O3—C8—C6	115.63 (12)
N1—C6—C8	113.36 (12)	C4—C5—C6	117.66 (13)
C5—C6—C8	124.56 (12)	C4—C5—H6	119.8 (14)
N2—C3—C4	122.16 (13)	C6—C5—H6	122.5 (14)
N2—C3—C7	112.66 (12)	H62—O6—H61	103 (2)
C4—C3—C7	125.17 (13)	N3^i—N3—H51	106.7 (14)
O2—C7—O1	126.02 (13)	N3^i—N3—H53	105.3 (14)
O2—C7—C3	119.91 (13)	H51—N3—H53	108 (2)
O1—C7—C3	114.07 (12)	N3^i—N3—H52	109.5 (13)
C5—C4—C3	117.50 (13)	H51—N3—H52	117.5 (18)
C5—C4—H5	120.3 (13)	H53—N3—H52	109.0 (18)

Symmetry code: (i) −x+1, −y+2, −z+2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O6—H62···N1^ii	0.81 (3)	2.23 (3)	3.031 (2)	174 (3)
N3—H51···O4^iii	0.96 (2)	1.85 (2)	2.770 (2)	160 (2)
O6—H61···O4^iii	0.98 (3)	1.99 (3)	2.9581 (18)	168 (2)
O6—H61···N1^iii	0.98 (3)	2.45 (2)	3.039 (2)	118.5 (18)
N3—H53···N2^ii	0.91 (2)	1.95 (2)	2.8287 (18)	163 (2)
N3—H53···O2^ii	0.91 (2)	2.50 (2)	3.0627 (19)	120.7 (17)
N3—H52···O6^iv	1.04 (2)	1.71 (2)	2.7473 (18)	176.6 (19)
O1—H1···O3^v	1.03 (4)	1.51 (4)	2.5152 (16)	165 (3)

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