Sodium 5-nitro-2-pyridonate trihydrate

The title compound, alternatively sodium pyridin-2-olate trihydrate, Na⁺·C₅H₃N₂O₃⁻·3H₂O, crystallizes in the P space group. It is made up of edge-shared chains of NaO₆ octahedra with five water mol­ecules and one 5-nitro-2-pyridonate anion. Four of these water mol­ecules are bicoordinating, involved in connecting the adjacent octahedra, and the fifth is coordinated to only one octahedron. The crystal structure is stabilized by a network of strong O—H...O and O—H...N interactions. The organic moieties occupy the space between the chains with an antiparallel alignment.

Computing details

Data collection: KappaCCD (Enraf-Nonius, 1998); cell refinement: KappaCCD; data reduction: TEXSAN (Molecular Structure Corporation, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: TEXSAN; molecular graphics: ORTEP (Johnson, 1976) and MOLVIEW (Cense, 1990); software used to prepare material for publication: TEXSAN.

(Na5N2py)

Crystal data

Na(C5H3N2O3)·3H2O	Z = 2
Mr = 216.13	F(000) = 224.00
Triclinic, P1	Dx = 1.562 Mg m^−3
a = 7.0044 (5) Å	Ag Kα radiation, λ = 0.5608 Å
b = 11.182 (1) Å	Cell parameters from 2258 reflections
c = 6.3971 (8) Å	θ = 2,81–22,61°
α = 102.978 (8)°	µ = 0.10 mm^−1
β = 104.697 (4)°	T = 296 K
γ = 74.017 (8)°	Needle, yellow
V = 459.40 (9) Å^3	0.34 × 0.14 × 0.11 mm

Data collection

KappaCCD diffractometer	1573 reflections with I > 3.00σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.000
Graphite monochromator	θmax = 22.6°, θmin = 2.8°
φ scans	h = −9→8
2258 measured reflections	k = −15→14
2258 independent reflections	l = 0→8

Refinement

Refinement on F	0 restraints
Least-squares matrix: full	0 constraints
R[F^2 > 2σ(F^2)] = 0.051	H-atom parameters not refined
wR(F^2) = 0.057	Weighting scheme based on measured s.u.'s w = 1/[σ^2(Fo)]
S = 1.91	(Δ/σ)max < 0.001
1573 reflections	Δρmax = 0.31 e Å^−3
127 parameters	Δρmin = −0.28 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Na1	0.60107 (8)	0.44741 (5)	0.75827 (8)	0.0414 (2)
O1	0.9347 (2)	−0.30740 (9)	0.6454 (2)	0.0450 (3)
O2	0.6122 (2)	0.13815 (11)	0.1563 (2)	0.0690 (4)
O3	0.6263 (2)	0.24290 (10)	0.4802 (2)	0.0698 (4)
O4	0.9128 (2)	0.3444 (2)	0.9266 (2)	0.0906 (5)
O5	0.5640 (2)	0.63327 (9)	1.0299 (2)	0.0470 (3)
O6	0.27311 (13)	0.50049 (9)	0.5196 (2)	0.0406 (3)
N1	0.7957 (2)	−0.19659 (11)	0.3649 (2)	0.0501 (4)
N2	0.6485 (2)	0.14286 (11)	0.3564 (2)	0.0391 (4)
C1	0.8650 (2)	−0.20009 (12)	0.5839 (2)	0.0328 (4)
C2	0.8558 (2)	−0.08602 (13)	0.7355 (2)	0.0411 (4)
C3	0.7846 (2)	0.02772 (13)	0.6660 (2)	0.0406 (4)
C4	0.7209 (2)	0.02791 (12)	0.4430 (2)	0.0310 (4)
C5	0.7277 (2)	−0.08527 (13)	0.3005 (2)	0.0464 (4)
H1	0.9064	−0.0890	0.9084	0.062*
H2	0.7776	0.1143	0.7810	0.061*
H3	0.6745	−0.0824	0.1273	0.070*
H4	1.0199	0.3138	0.8470	0.137*
H5	0.9576	0.3296	1.0336	0.137*
H6	0.6662	0.6673	1.1405	0.071*
H7	0.5131	0.6862	0.9925	0.071*
H8	0.1888	0.5589	0.5766	0.061*
H9	0.2200	0.4385	0.4619	0.061*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Na1	0.0456 (4)	0.0411 (4)	0.0359 (4)	−0.0055 (3)	0.0073 (2)	0.0100 (3)
O1	0.0548 (6)	0.0331 (6)	0.0442 (6)	−0.0059 (5)	0.0039 (5)	0.0133 (5)
O2	0.1104 (10)	0.0446 (7)	0.0462 (8)	−0.0076 (7)	0.0053 (6)	0.0208 (6)
O3	0.1015 (10)	0.0264 (6)	0.0678 (9)	−0.0067 (6)	0.0088 (7)	0.0003 (6)
O4	0.0630 (8)	0.1352 (13)	0.0460 (8)	0.0288 (8)	0.0081 (6)	0.0276 (8)
O5	0.0608 (7)	0.0361 (6)	0.0439 (6)	−0.0153 (5)	0.0000 (5)	0.0131 (5)
O6	0.0380 (5)	0.0329 (5)	0.0501 (6)	−0.0059 (4)	0.0103 (4)	0.0066 (4)
N1	0.0832 (9)	0.0269 (7)	0.0315 (7)	−0.0061 (6)	0.0049 (6)	0.0031 (5)
N2	0.0413 (7)	0.0301 (7)	0.0448 (8)	−0.0076 (5)	0.0062 (5)	0.0079 (6)
C1	0.0327 (7)	0.0330 (8)	0.0332 (8)	−0.0067 (5)	0.0061 (5)	0.0083 (6)
C2	0.0513 (8)	0.0393 (9)	0.0291 (8)	−0.0105 (7)	0.0019 (6)	0.0055 (6)
C3	0.0505 (8)	0.0334 (8)	0.0335 (8)	−0.0104 (6)	0.0058 (6)	−0.0012 (6)
C4	0.0327 (7)	0.0264 (7)	0.0338 (8)	−0.0058 (5)	0.0071 (5)	0.0053 (6)
C5	0.0724 (10)	0.0318 (8)	0.0294 (8)	−0.0059 (7)	0.0080 (7)	0.0043 (6)

Geometric parameters (Å, º)

Na1—O3	2.556 (2)	O6—H8	0.84
Na1—O4	2.288 (2)	O6—H9	0.84
Na1—O5	2.391 (2)	N1—C1	1.367 (2)
Na1—O5^i	2.430 (2)	N1—C5	1.323 (3)
Na1—O6	2.416 (1)	N2—C4	1.426 (2)
Na1—O6^ii	2.412 (1)	C1—C2	1.415 (3)
O1—C1	1.275 (2)	C2—C3	1.362 (3)
O2—N2	1.232 (2)	C2—H1	1.08
O3—N2	1.213 (2)	C3—C4	1.383 (3)
O4—H4	0.96	C3—H2	1.07
O4—H5	0.71	C4—C5	1.380 (3)
O5—H6	0.97	C5—H3	1.08
O5—H7	0.66
O1···H9^iii	1.9598	O2···H3^vi	2.4589
O1···H5^iv	2.0465	O2···C5^vi	3.320 (3)
O1···H8^v	2.0571	O4···N1^vii	3.011 (2)
O1···O4^iv	2.755 (2)	O5···N1^viii	2.992 (2)
O1···O6^iii	2.797 (2)	N1···H6^ix	2.0774
O1···O6^v	2.875 (2)	N1···H4^vii	2.0931
O3—Na1—O4	83.10 (7)	Na1—O6—Na1	95.45 (5)
O3—Na1—O5	176.08 (6)	Na1—O6—H8	114.5
O3—Na1—O5^i	91.06 (6)	Na1—O6—H9	114.2
O3—Na1—O6	81.50 (6)	Na1—O6^ii—H8^ii	115.3
O3—Na1—O6^ii	78.25 (6)	Na1—O6^ii—H9^ii	107.7
O4—Na1—O5	97.38 (7)	H8—O6—H9	109.1
O4—Na1—O5^i	90.69 (6)	C1—N1—C5	118.4 (2)
O4—Na1—O6	164.41 (7)	O2—N2—O3	121.3 (2)
O4—Na1—O6^ii	94.65 (6)	O2—N2—C4	118.9 (2)
O5—Na1—O5	85.05 (5)	O3—N2—C4	119.7 (2)
O5—Na1—O6	97.82 (5)	O1—C1—N1	118.4 (2)
O5—Na1—O6^ii	105.56 (5)	O1—C1—C2	121.9 (2)
O5^i—Na1—O6	87.22 (5)	N1—C1—C2	119.7 (2)
O5^i—Na1—O6^ii	167.35 (5)	C1—C2—C3	120.9 (2)
O6—Na1—O6	84.55 (5)	C1—C2—H1	119.6
Na1—O3—N2	176.2 (1)	C3—C2—H1	119.4
Na1—O4—H4	119.2	C2—C3—C4	117.8 (2)
Na1—O4—H5	135.7	C2—C3—H2	120.9
H4—O4—H5	105.1	C4—C3—H2	121.2
Na1—O5—Na1	94.95 (5)	N2—C4—C3	121.4 (2)
Na1—O5—H6	129.6	N2—C4—C5	119.1 (2)
Na1—O5—H7	115.6	C3—C4—C5	119.5 (2)
Na1—O5^i—H6^i	102.9	N1—C5—C4	123.5 (2)
Na1—O5^i—H7^i	116.7	N1—C5—H3	118.5
H6—O5—H7	97.7	C4—C5—H3	118.0

Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x+1, −y+1, −z+1; (iii) −x+1, −y, −z+1; (iv) −x+2, −y, −z+2; (v) x+1, y−1, z; (vi) −x+1, −y, −z; (vii) −x+2, −y, −z+1; (viii) x, y+1, z+1; (ix) x, y−1, z−1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H5···O1^iv	0.71	2.05	2.755 (2)	173
O6—H8···O1^x	0.84	2.06	2.875 (2)	166
O6—H9···O1^iii	0.84	1.96	2.797 (2)	171
O5—H7···O2^ii	0.66	2.24	2.891 (2)	170
C5—H3···O2^vi	1.08	2.46	3.320 (3)	136
O4—H4···N1^vii	0.96	2.09	3.011 (2)	160
O5—H6···N1^viii	0.97	2.08	2.992 (2)	157

Symmetry codes: (ii) −x+1, −y+1, −z+1; (iii) −x+1, −y, −z+1; (iv) −x+2, −y, −z+2; (vi) −x+1, −y, −z; (vii) −x+2, −y, −z+1; (viii) x, y+1, z+1; (x) x−1, y+1, z.