catena-Poly[[(6-carb-oxy-pyrazine-2-carboxyl-ato)lithium]-μ-aqua].

The asymmetric unit of the title compound, [Li(C(6)H(3)N(2)O(4))(H(2)O)](n), contains an Li(I) ion with a distorted trigonal-bipyramidal coordination environment. It is chelated by a singly protonated ligand mol-ecule via its heterocyclic N atom, by two O aoms, each donated by an adjacent carboxyl-ate group, and is further coordinated by a water O atom which acts as a bridge, forming a mol-ecular ribbon. A proton attached to one of the carboxyl-ate O atoms is situated on an inversion centre and forms a short centrosymmetric hydrogen bond, generating mol-ecular layers parallel to the ac plane. These layers are held together by weak O-H⋯O hydrogen bonds in which the coordinated water mol-ecules act as donors, whereas carboxyl-ate O atoms are acceptors.

Related literature

For the structures of three lithium complexes with pyrazine-2,3-dicarboxyl­ate and water ligands, see: Tombul et al. (2008 ▶); Tombul & Guven (2009) ▶; Starosta & Leciejewicz (2011b ▶). For the structure of a LiI complex with a pyrazine-2,5-dicarboxyl­ate ligand, see: Starosta & Leciejewicz (2011a ▶) and for the structure of a LiI complex with pyrazine-2,3,5,6-tetra­carboxyl­ate, see: Starosta & Leciejewicz (2010 ▶). The structure of pyrazine-2,6-dicarboxyl­ate acid dihydrate has been also reported, see: Ptasiewicz-Bąk & Leciejewicz (2003 ▶).

Experimental

Crystal data

[Li(C6H3N2O4)(H2O)]

M = 192.06

Monoclinic,

a = 3.5346 (7) Å

b = 12.519 (3) Å

c = 8.3583 (17) Å

β = 97.86 (3)°

V = 366.37 (13) Å3

Z = 2

Mo Kα radiation

μ = 0.15 mm−1

T = 293 K

0.31 × 0.22 × 0.08 mm

Data collection

Kuma KM-4 four-circle diffractometer

Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008 ▶) T min = 0.954, T max = 0.973

1262 measured reflections

1106 independent reflections

729 reflections with I > 2σ(I)

R int = 0.027

3 standard reflections every 200 reflections intensity decay: 1.3%

Refinement

R[F 2 > 2σ(F 2)] = 0.054

wR(F 2) = 0.171

S = 1.09

1106 reflections

75 parameters

2 restraints

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.38 e Å−3

Δρmin = −0.31 e Å−3

Data collection: KM-4 Software (Kuma, 1996 ▶); cell refinement: KM-4 Software; 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: SHELXTL.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536811046198/kp2364sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811046198/kp2364Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

[Li(C6H3N2O4)(H2O)]	F(000) = 196
Mr = 192.06	Dx = 1.741 Mg m−3
Monoclinic, P21/m	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yb	Cell parameters from 25 reflections
a = 3.5346 (7) Å	θ = 6–15°
b = 12.519 (3) Å	µ = 0.15 mm−1
c = 8.3583 (17) Å	T = 293 K
β = 97.86 (3)°	Plates, colourless
V = 366.37 (13) Å3	0.31 × 0.22 × 0.08 mm
Z = 2

Kuma KM-4 four-circle diffractometer	729 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.027
graphite	θmax = 30.1°, θmin = 3.0°
Profile data from ω/2θ scans	h = 0→4
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008)	k = −17→0
Tmin = 0.954, Tmax = 0.973	l = −11→11
1262 measured reflections	3 standard reflections every 200 reflections
1106 independent reflections	intensity decay: 1.3%

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)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.171	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	w = 1/[σ2(Fo2) + (0.1039P)2 + 0.0995P] where P = (Fo2 + 2Fc2)/3
1106 reflections	(Δ/σ)max < 0.001
75 parameters	Δρmax = 0.38 e Å−3
2 restraints	Δρmin = −0.31 e Å−3

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
N1	0.2901 (6)	0.7500	0.2305 (2)	0.0216 (4)
O1	0.4179 (5)	0.57853 (10)	0.07619 (15)	0.0333 (4)
C2	0.2425 (5)	0.65866 (13)	0.30619 (19)	0.0216 (4)
N2	0.0883 (7)	0.7500	0.5385 (2)	0.0297 (5)
O2	0.2587 (5)	0.47052 (12)	0.27081 (17)	0.0371 (4)
C3	0.1409 (5)	0.65888 (14)	0.4618 (2)	0.0269 (4)
H3	0.1092	0.5942	0.5130	0.032*
C7	0.3068 (5)	0.55822 (14)	0.2144 (2)	0.0245 (4)
O3	0.8304 (9)	0.7500	−0.1306 (3)	0.0572 (8)
Li1	0.3902 (17)	0.7500	−0.0132 (8)	0.0456 (13)
H31	0.866 (12)	0.6976 (8)	−0.186 (4)	0.092 (14)*
H1	0.5000	0.5000	0.0000	0.10 (2)*

	U11	U22	U33	U12	U13	U23
N1	0.0281 (10)	0.0194 (9)	0.0187 (8)	0.000	0.0084 (7)	0.000
O1	0.0561 (9)	0.0228 (7)	0.0254 (6)	0.0003 (6)	0.0216 (6)	−0.0014 (5)
C2	0.0253 (8)	0.0206 (7)	0.0198 (7)	−0.0006 (6)	0.0059 (5)	0.0012 (6)
N2	0.0404 (12)	0.0314 (12)	0.0196 (9)	0.000	0.0124 (8)	0.000
O2	0.0584 (10)	0.0223 (7)	0.0340 (7)	0.0004 (6)	0.0186 (6)	0.0037 (5)
C3	0.0348 (9)	0.0261 (9)	0.0217 (7)	0.0000 (7)	0.0109 (6)	0.0031 (6)
C7	0.0300 (8)	0.0223 (7)	0.0225 (7)	0.0009 (6)	0.0080 (6)	0.0002 (6)
O3	0.0642 (18)	0.084 (2)	0.0247 (10)	0.000	0.0122 (10)	0.000
Li1	0.039 (3)	0.053 (3)	0.046 (3)	0.000	0.007 (2)	0.000

N1—C2i	1.3287 (18)	O2—C7	1.216 (2)
N1—C2	1.3287 (18)	C3—H3	0.9300
N1—Li1	2.115 (7)	O3—Li1	1.950 (7)
O1—C7	1.295 (2)	O3—Li1ii	2.085 (7)
O1—Li1	2.271 (2)	O3—H31	0.825 (17)
O1—H1	1.2275 (13)	Li1—O3iii	2.085 (7)
C2—C3	1.396 (2)	Li1—O1i	2.271 (2)
C2—C7	1.506 (2)	Li1—Li1iii	3.5346 (7)
N2—C3i	1.334 (2)	Li1—Li1ii	3.5346 (7)
N2—C3	1.334 (2)
C2i—N1—C2	118.8 (2)	O3—Li1—N1	137.3 (3)
C2i—N1—Li1	120.51 (10)	O3iii—Li1—N1	100.4 (3)
C2—N1—Li1	120.51 (10)	O3—Li1—O1i	99.45 (16)
C7—O1—Li1	118.33 (19)	O3iii—Li1—O1i	98.65 (16)
C7—O1—H1	115.31 (13)	N1—Li1—O1i	71.83 (16)
Li1—O1—H1	126.08 (17)	O3—Li1—O1	99.45 (16)
N1—C2—C3	120.51 (16)	O3iii—Li1—O1	98.65 (16)
N1—C2—C7	115.98 (14)	N1—Li1—O1	71.84 (16)
C3—C2—C7	123.52 (15)	O1i—Li1—O1	141.9 (3)
C3i—N2—C3	117.5 (2)	O3—Li1—Li1iii	150.10 (19)
N2—C3—C2	121.34 (16)	O3iii—Li1—Li1iii	27.79 (19)
N2—C3—H3	119.3	N1—Li1—Li1iii	72.60 (17)
C2—C3—H3	119.3	O1i—Li1—Li1iii	89.89 (15)
O2—C7—O1	126.77 (16)	O1—Li1—Li1iii	89.89 (15)
O2—C7—C2	121.16 (15)	O3—Li1—Li1ii	29.90 (19)
O1—C7—C2	112.07 (15)	O3iii—Li1—Li1ii	152.21 (18)
Li1—O3—Li1ii	122.3 (3)	N1—Li1—Li1ii	107.40 (17)
Li1—O3—H31	119 (3)	O1i—Li1—Li1ii	90.11 (15)
Li1ii—O3—H31	93 (3)	O1—Li1—Li1ii	90.11 (15)
O3—Li1—O3iii	122.3 (3)	Li1iii—Li1—Li1ii	179.999 (1)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H31···O2iv	0.83 (2)	2.24 (2)	2.9987 (19)	152 (3)
O1—H1···O1iv	1.23 (1)	1.23 (1)	2.455 (3)	180.(1)

Table 1

Selected bond lengths (Å)

N1—Li1	2.115 (7)
O1—Li1	2.271 (2)
O3—Li1	1.950 (7)
O3—Li1i	2.085 (7)
Li1—O1ii	2.271 (2)

Symmetry codes: (i) ; (ii) .

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H31⋯O2iii	0.83 (2)	2.24 (2)	2.9987 (19)	152 (3)
O1—H1⋯O1iii	1.23 (1)	1.23 (1)	2.455 (3)	180 (1)

Symmetry code: (iii) .