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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890

(μ-Di­hydrogen pyrazine-2,3,5,6-tetra­carboxyl­ato-κ6O2,N1,O6;O3,N4,O5)bis­­(di­aqua­lithium) monohydrate

aInstitute of Nuclear Chemistry and Technology, ul.Dorodna 16, 03-195 Warszawa, Poland
*Correspondence e-mail: j.leciejewicz@ichtj.waw.pl

(Received 17 March 2014; accepted 1 April 2014; online 9 April 2014)

The structure of the title compound, [Li2(C8H2N2O8)(H2O)4]·H2O, is composed of dinuclear mol­ecules in which the ligand bridges two symmetry-related LiI ions, each coordinated also by two water O atoms, in an O,N,O′-manner. The Li and N atoms occupy special positions on twofold rotation axes, whereas a crystal water mol­ecule is located at the inter­section of three twofold rotation axes. The LiI cation shows a distorted trigonal–bipyramidal coordination. Two carboxyl­ate groups remain protonated and form short inter­ligand hydrogen bonds. The mol­ecules are held together by a network of hydrogen bonds in which the coordinating and solvation water mol­ecules act as donors and carboxyl­ate O atoms as acceptors, forming a three-dimensional architecture.

Related literature

For the structure of a lithium complex with pyrazine-2,3,5,6-tetra­carboxyl­ate and water ligands, see: Starosta & Leciejewicz (2010[Starosta, W. & Leciejewicz, J. (2010). Acta Cryst. E66, m1561-m1562.]). The structure of pyrazine-2,3,5,6-tetra­carb­oxy­lic acid dihydrate was reported by Vishweshwar et al. (2001[Vishweshwar, P., Nangia, A. & Lynch, V. M. (2001). Chem. Commun. pp. 179-180.]).

[Scheme 1]

Experimental

Crystal data
  • [Li2(C8H2N2O8)(H2O)4]·H2O

  • Mr = 358.08

  • Orthorhombic, I b a m

  • a = 6.3807 (4) Å

  • b = 9.8331 (6) Å

  • c = 22.1717 (16) Å

  • V = 1391.10 (16) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.16 mm−1

  • T = 293 K

  • 0.12 × 0.10 × 0.06 mm

Data collection
  • Agilent SuperNova (Dual, Cu at zero, Eos) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, England.]) Tmin = 0.979, Tmax = 0.993

  • 3622 measured reflections

  • 917 independent reflections

  • 769 reflections with I > 2σ(I)

  • Rint = 0.061

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.100

  • S = 1.06

  • 917 reflections

  • 78 parameters

  • 4 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Selected bond lengths (Å)

Li1—N1 2.053 (4)
Li1—O1 2.1581 (17)
Li1—O3 1.969 (3)
Li1—O3i 1.969 (3)
Li1—O1i 2.1580 (17)
Symmetry code: (i) -x+2, -y, z.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H1⋯O2ii 1.20 (1) 1.20 (1) 2.402 (3) 177 (8)
O3—H32⋯O3iii 0.87 (2) 2.00 (2) 2.839 (3) 163 (4)
O3—H31⋯O1iv 0.86 (2) 2.03 (2) 2.8825 (19) 177 (2)
O3—H33⋯O4v 0.86 (2) 2.10 (2) 2.9454 (17) 169 (6)
Symmetry codes: (ii) x, y, -z; (iii) [-x+2, y, -z+{\script{1\over 2}}]; (iv) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z]; (v) [-x+{\script{3\over 2}}, -y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CrysAlis PRO (Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The structure of the title compound reveals a dimeric unit of 2/m crystallographic symmetry in which two symmetry related doubly aqua-coordinated Li(I) ions are bridged by a ligand molecule via its both N,O,O bonding sites (Fig.1). The Li(I) cation is in distorted trigonal bipyramidal coordination. Its equatorial plane is formed by N1, O3, O3(i) and the Li1 atoms; the O1 and O1(i) atoms are at the apices. The O1—Li—O1(i) angle is 151.7 (3)° and Li—O and Li—N bond distances are listed in Table 1. The pyrazine ring is planar. Two carboxylate groups remain protonated to maintain charge balance. Bond distances and bond angles within the hetero-ring do not differ from those reperted in the structure of the parent acid (Vishweshwar et al., 2001). Short, symmetric hydrogen bond is formed in which the carboxylate O2 atom is as a donor and the O1(ii) is as an acceptor (Table 2). A dihedral angle formed with the pyrazine ring by the carboxylic group C1/O1/O2 is 4.7 (1)°. Fourier maps show a clear disorder in hydrogen positions at the solvation and coordinated water molecules with position occupancy of aproximately 0.5. The title molecules are held together by a network of hydrogen bonds (Table 2) in which coordinated water molecules act as donors and carboxylate O atoms as acceptors forming molecular layers propagating in the crystal a direction (Fig.2). A view of a single layer is displayed in Fig. 2. The layers are linked by weak hydrogen bonds in which solvation water molecules are involved. Another Li(I) complex with the title ligand is known (Starosta & Leciejewicz, 2010). Its polarized dinuclear structural unit is built of a doubly protonated ligand molecule chelated by its N,O,O bonding moiety to an Li(I) ion and an Li(I) ion coordinated by four aqua O atoms. Two of the latter bridge the Li ions to form a catenated polymeric structure propagating in the crystal a direction.

Related literature top

For the structure of a lithium complex with pyrazine-2,3,5,6-tetracarboxylate and water ligands, see: Starosta & Leciejewicz (2010). The structure of pyrazine-2,3,5,6-tetracarboxylic acid dihydrate was reported by Vishweshwar et al. (2001).

Experimental top

Hot aqueous solutions, one containing 1 mmol of pyrazine-2,3,5,6-tetracarboxylic acid dihydrate, the other 4 mmol s of lithium nitrate (Aldrich) were mixed and boiled under reflux with constant stirring for 6 h. After cooling to room temperature the solution was left to evaporate. A couple of days latter, single-crystal blocks deposited on the bottom of a crystallization pot. They were washed with cold ethanol and dried in air.

Refinement top

Water and carboxylate H atoms were found in the Fourier map and refined isotropically.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); 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 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecule of the title compound with atom labelling scheme and 50% probability displacement ellipsoids. Symmetry code: i -x, -y, z; ii x, y, -z; iii -x, -y, -z.
[Figure 2] Fig. 2. A single molecular layer composed of the dimers linked by a hydrogen bond network as viewed along the crystal c direction.
(µ-Dihydrogen pyrazine-2,3,5,6-tetracarboxylato-κ6O2,N1,O6;O3,N4,O5)bis(diaqualithium) monohydrate top
Crystal data top
[Li2(C8H2N2O8)(H2O)4]·H2OZ = 4
Mr = 358.08F(000) = 736
Orthorhombic, IbamDx = 1.710 Mg m3
Hall symbol: -I 2 2cMo Kα radiation, λ = 0.71073 Å
a = 6.3807 (4) ŵ = 0.16 mm1
b = 9.8331 (6) ÅT = 293 K
c = 22.1717 (16) ÅPlate, colourless
V = 1391.10 (16) Å30.12 × 0.10 × 0.06 mm
Data collection top
Agilent SuperNova (Dual, Cu at zero, Eos)
diffractometer
917 independent reflections
Radiation source: SuperNova (Mo) X-ray Source769 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.061
Detector resolution: 16.0131 pixels mm-1θmax = 29.3°, θmin = 3.7°
ω scansh = 88
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
k = 1213
Tmin = 0.979, Tmax = 0.993l = 2929
3622 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.100H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.024P)2 + 2.020P]
where P = (Fo2 + 2Fc2)/3
917 reflections(Δ/σ)max < 0.001
78 parametersΔρmax = 0.25 e Å3
4 restraintsΔρmin = 0.22 e Å3
Crystal data top
[Li2(C8H2N2O8)(H2O)4]·H2OV = 1391.10 (16) Å3
Mr = 358.08Z = 4
Orthorhombic, IbamMo Kα radiation
a = 6.3807 (4) ŵ = 0.16 mm1
b = 9.8331 (6) ÅT = 293 K
c = 22.1717 (16) Å0.12 × 0.10 × 0.06 mm
Data collection top
Agilent SuperNova (Dual, Cu at zero, Eos)
diffractometer
917 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
769 reflections with I > 2σ(I)
Tmin = 0.979, Tmax = 0.993Rint = 0.061
3622 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0474 restraints
wR(F2) = 0.100H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.25 e Å3
917 reflectionsΔρmin = 0.22 e Å3
78 parameters
Special details top

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 (Å2) top
xyzUiso*/UeqOcc. (<1)
N11.00000.00000.06097 (8)0.0207 (4)
O10.7218 (2)0.11263 (14)0.12977 (5)0.0328 (3)
O31.1372 (3)0.14626 (15)0.19959 (7)0.0376 (4)
O20.5112 (3)0.16787 (13)0.05418 (6)0.0356 (4)
C20.8398 (3)0.05696 (15)0.03197 (7)0.0203 (3)
C70.6800 (3)0.11721 (16)0.07586 (8)0.0251 (4)
Li11.00000.00000.15359 (19)0.0360 (10)
O40.00000.50000.25000.0595 (9)
H311.158 (4)0.219 (2)0.1789 (10)0.056 (8)*
H10.506 (12)0.168 (4)0.00000.097 (15)*
H321.068 (6)0.161 (4)0.2328 (13)0.037 (13)*0.50
H410.043 (12)0.459 (6)0.2190 (17)0.10 (3)*0.50
H331.254 (6)0.111 (6)0.211 (2)0.08 (2)*0.50
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0218 (8)0.0189 (8)0.0214 (9)0.0016 (8)0.0000.000
O10.0355 (7)0.0383 (7)0.0244 (6)0.0065 (6)0.0072 (6)0.0025 (5)
O30.0474 (9)0.0347 (8)0.0308 (8)0.0074 (7)0.0008 (7)0.0004 (6)
O20.0293 (7)0.0400 (7)0.0376 (7)0.0154 (6)0.0050 (7)0.0002 (6)
C20.0198 (8)0.0174 (7)0.0239 (8)0.0002 (6)0.0008 (6)0.0009 (6)
C70.0258 (8)0.0203 (7)0.0293 (9)0.0019 (6)0.0047 (7)0.0008 (6)
Li10.046 (2)0.039 (2)0.024 (2)0.005 (2)0.0000.000
O40.076 (3)0.065 (2)0.0372 (19)0.0000.0000.000
Geometric parameters (Å, º) top
N1—C2i1.3313 (18)O2—C71.280 (2)
N1—C21.3313 (18)O2—H11.202 (3)
Li1—N12.053 (4)C2—C2ii1.418 (3)
O1—C71.226 (2)C2—C71.529 (2)
Li1—O12.1581 (17)Li1—O3i1.969 (3)
Li1—O31.969 (3)Li1—O1i2.1580 (17)
O3—H310.858 (16)Li1—H332.33 (5)
O3—H320.870 (19)O4—H410.84 (2)
O3—H330.86 (2)
C2i—N1—C2122.24 (19)O2—C7—C2118.22 (15)
C2i—N1—Li1118.88 (10)O3i—Li1—O3117.6 (2)
C2—N1—Li1118.88 (10)O3i—Li1—N1121.21 (11)
C7—O1—Li1115.89 (16)O3—Li1—N1121.21 (11)
Li1—O3—H31113.4 (17)O3i—Li1—O1i96.76 (7)
Li1—O3—H32110 (3)O3—Li1—O1i97.81 (7)
H31—O3—H32113 (3)N1—Li1—O1i75.84 (11)
Li1—O3—H33104 (4)O3i—Li1—O197.81 (7)
H31—O3—H33111 (4)O3—Li1—O196.76 (7)
H32—O3—H33105 (4)N1—Li1—O175.84 (11)
C7—O2—H1113 (4)O1i—Li1—O1151.7 (2)
N1—C2—C2ii118.88 (10)O3i—Li1—H33111.5 (14)
N1—C2—C7111.58 (14)O3—Li1—H3320.9 (10)
C2ii—C2—C7129.53 (9)N1—Li1—H33123.2 (14)
O1—C7—O2124.31 (16)O1i—Li1—H3378.6 (10)
O1—C7—C2117.47 (16)O1—Li1—H33117.7 (10)
Symmetry codes: (i) x+2, y, z; (ii) x, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H1···O2ii1.20 (1)1.20 (1)2.402 (3)177 (8)
O3—H32···O3iii0.87 (2)2.00 (2)2.839 (3)163 (4)
O3—H31···O1iv0.86 (2)2.03 (2)2.8825 (19)177 (2)
O3—H33···O4v0.86 (2)2.10 (2)2.9454 (17)169 (6)
Symmetry codes: (ii) x, y, z; (iii) x+2, y, z+1/2; (iv) x+1/2, y+1/2, z; (v) x+3/2, y+1/2, z+1/2.
Selected bond lengths (Å) top
Li1—N12.053 (4)Li1—O3i1.969 (3)
Li1—O12.1581 (17)Li1—O1i2.1580 (17)
Li1—O31.969 (3)
Symmetry code: (i) x+2, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H1···O2ii1.202 (3)1.202 (3)2.402 (3)177 (8)
O3—H32···O3iii0.870 (19)2.00 (2)2.839 (3)163 (4)
O3—H31···O1iv0.858 (16)2.026 (17)2.8825 (19)177 (2)
O3—H33···O4v0.86 (2)2.10 (2)2.9454 (17)169 (6)
Symmetry codes: (ii) x, y, z; (iii) x+2, y, z+1/2; (iv) x+1/2, y+1/2, z; (v) x+3/2, y+1/2, z+1/2.
 

References

First citationAgilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, England.
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals
First citationStarosta, W. & Leciejewicz, J. (2010). Acta Cryst. E66, m1561–m1562.  Web of Science CrossRef CAS IUCr Journals
First citationVishweshwar, P., Nangia, A. & Lynch, V. M. (2001). Chem. Commun. pp. 179–180.  Web of Science CSD CrossRef

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ISSN: 2056-9890
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