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metal-organic papers

Acta Cryst.(2006). E62, m945–m947 doi:10.1107/S1600536806008130 Tombulet al. [Na(C

6H3N2O4)(H2O)2]

m945

Acta Crystallographica Section E Structure Reports Online

ISSN 1600-5368

Poly[

l

-aqua-aqua-

l

-3-carboxypyrazine-2-carboxylato-sodium(I)]

Mustafa Tombul,a* Kutalmıs¸ Gu¨venb and Nazım Alkıs¸a

a

Department of Chemistry, University of Kırıkkale, Campus, Yahs¸ihan 71450, Kırıkkale, Turkey, andbDepartment of Physics, University

of Kırıkkale, Campus, Yahs¸ihan 71450, Kırıkkale, Turkey

Correspondence e-mail: mustafatombul@hotmail.com

Key indicators

Single-crystal X-ray study T= 295 K

Mean(C–C) = 0.002 A˚ Rfactor = 0.029 wRfactor = 0.089

Data-to-parameter ratio = 15.6

For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.

Received 28 February 2006 Accepted 6 March 2006

#2006 International Union of Crystallography All rights reserved

The crystal structure of the title compound, [Na(C6H3 -N2O4)(H2O)2]n, consists of molecular ribbons containing

octahedral NaO5N units. Two adjacent Na atoms are bridged by two water molecules to give a centrosymmetric dimeric unit. Each Na centre is coordinated by two carboxylate groups. The ligand also uses one N atom to coordinate to Na. In addition, each Na atom is coordinated by one water O atom, raising the coordination number to six. One of the carboxyl groups retains its H atom, which takes part in an O—H O [O O = 2.563 (1) A˚ ] intramolecular hydrogen bond.

Comment

The title compound (I), was obtained as a colourless powder during an attempt to synthesize a borate ester product from the reaction of Na2CO3with B(OH)3and pyrazine-2,3-dicar-boxylic acid. Recrystallization yielded crystals suitable for a diffraction study, the results of which are reported here.

The structure of (I) is shown in Fig. 1 and selected bond lengths and angles are presented in Table 1. Since the single-crystal X-ray analysis of pyrazine-2,3 dicarboxylic acid was first determined (Takusagawa & Shimada, 1973), a variety of metal–organic compounds of pyrazine-2,3-dicarboxylic acid have been characterized crystallographically due to the growing interest in supramolecular chemistry. These include the calcium (Ptasiewicz-Bak & Leciejewicz, 1997a; Starosta & Leciejewicz, 2005) and magnesium (Ptasiewicz-Bak & Lecie-jewicz, 1997b) complexes.

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the parent acid (Takusagawa & Shimada, 1973). The Na— O(carboxylate) interaction modes, the Na coordination scheme and the range of Na—O bond lengths agree well with those most frequently observed in a large number of Na complexes with carboxylate ligands (Evanset al., 2001). The bridged Na Na distance of 3.464 (2) A˚ is similar to those reported for other bridged systems (Evans et al., 2001; Albertssonet al., 1973). The planes of the carboxylate groups (C6/O2/O6) and (C1/O4/O5) form dihedral angles with the ring plane of 71.99 (5) and 17.43 (1), respectively.

An interesting feature to note in compound (I) is that an asymmetrical intramolecular hydrogen bond of 2.563 (1) A˚ occurs, linking the coordinated water O atoms with the hydroxyl O atoms of adjacent ribbons (Table 2). Atom H1 involved in this bond maintains the charge balance within the structure.

The two crystallographically independent water molecules are involved in normal, slightly bent, hydrogen bonds with hydrogen pyrazine-2,3-dicarboxylate (Table 2); the acceptors are carboxylate O atoms, with the exception of the water acceptor O1 noted above.

We note the following details for the configuration of the water molecules, in which marked differences occur in their environment. Atom O3 is coordinated to two NaIcations and, from the valence bond argument, this interaction involvessp3 -type water lone pairs. In contrast, atom O1 is coordinated to only one NaI cation, with the Na—O interaction approxi-mately along the bisector of the H—O—H angle, and the interaction therefore involvessp2-type water lone pairs. This coordination situation with respect to the lone-pair side of water molecules is typical for a monovalent metal salt hydrate (Chiari & Ferraris, 1982).

In compound (I), there are appreciable differences between the two carboxyl groups. The C—O distances at C6 are 1.208 and 1.304 A˚ , and these are fairly typical for a carboxylic acid group (Speakman, 1972). On the other hand, those at C1 are 1.245 and 1.253 A˚ , giving a strong indication of a carboxylate ion. As is typically the case, the mean value of the two C—O distances in the different carboxyl/carboxylate groups is almost the same, at 1.256 and 1.249 A˚ , respectively.

Experimental

To an aqueous solution (50 ml) containing Na2CO3(2 mmol, 0.212 g)

and B(OH)3 (4 mmol, 0.248 g), pyrazine-2,3-dicarboxylic acid

(8 mmol, 1.34 g) was added gradually with the immediate evolution of H2gas. The reaction mixture produced a colourless solution which

was stirred at 333 K for 7 h, until all became was formed. Single crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of a saturated aqueous solution at 298 K.

Crystal data

[Na(C6H3N2O4)(H2O)2]

Mr= 226.13

Triclinic,P1 a= 7.8581 (14) A˚ b= 8.4416 (19) A˚ c= 7.602 (2) A˚ = 108.05 (3) = 93.71 (2) = 70.139 (14) V= 450.45 (19) A˚3

Z= 2

Dx= 1.667 Mg m 3

MoKradiation Cell parameters from 25

reflections = 10.3–18.3 = 0.19 mm1

T= 295 (2) K Prism, colourless 0.40.40.2 mm

Data collection

Rigaku AFC-7S diffractometer !/2scans

Absorption correction: scan (MSC/AFC Diffractometer Control Software; Molecular Structure Corporation, 1991) Tmin= 0.928,Tmax= 0.963

2737 measured reflections 2561 independent reflections

2171 reflections withI> 2(I) Rint= 0.007

max= 30.0

h= 0!10 k=11!11 l=10!10 3 standard reflections

every 150 reflections intensity decay: 0.1%

Refinement

Refinement onF2

R[F2> 2(F2

)] = 0.029 wR(F2) = 0.089

S= 1.03 2561 reflections 164 parameters

All H-atom parameters refined

w= 1/[2(F

o2) + (0.1279P)2

+ 0.6038P]

whereP= (Fo2+ 2Fc2)/3

(/)max= 0.004

max= 0.40 e A˚

3

min=0.22 e A˚

3

Table 1

Selected geometric parameters (A˚ ,).

Na1—O4 2.3333 (12) Na1—O3 2.3407 (12) Na1—O3i

2.3976 (12) Na1—O2 2.4523 (10) Na1—O1 2.4734 (10) Na1—N2 2.5093 (13) O4—C1 1.2570 (14)

O5—C1 1.2402 (14) C2—N2 1.3388 (14) N1—C3 1.3387 (13) N1—C4 1.3381 (15) N2—C5 1.3333 (15) C6—O6 1.2081 (14)

O4—Na1—O3 118.02 (4) O4—Na1—O2 105.90 (4) O3—Na1—O2 80.13 (4) O4—Na1—O1 92.02 (4) O3—Na1—O1 78.04 (4) O2—Na1—O1 156.50 (3) O4—Na1—N2 68.81 (4) O3—Na1—N2 172.79 (4) O2—Na1—N2 96.00 (4)

O1—Na1—N2 104.74 (4) O4—Na1—O3i 155.20 (4) O3—Na1—O3i 86.07 (4) O2—Na1—O3i 82.79 (4) O1—Na1—O3i 87.15 (4) N2—Na1—O3i

87.42 (4) C6—O2—Na1 135.32 (7) Na1—O3—Na1i 93.93 (4)

Symmetry code: (i)xþ2;yþ1;z.

metal-organic papers

m946

Tombulet al. [Na(C

[image:2.610.46.296.72.212.2]

6H3N2O4)(H2O)2] Acta Cryst.(2006). E62, m945–m947

Figure 1

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[image:3.610.42.297.94.179.2]

Table 2

Hydrogen-bond geometry (A˚ ,).

D—H A D—H H A D A D—H A

O2—H1 O1i

0.91 (2) 1.66 (2) 2.563 (1) 168.18 (3) O1—H5 O4ii

0.89 (1) 1.79 (1) 2.671 (1) 176.61 (3) O1—H2 N1iii

0.83 (2) 2.11 (2) 2.902 (2) 164.67 (3) O3—H3 O5ii

0.81 (2) 1.88 (2) 2.688 (2) 177.33 (3) O3—H7 O6iv 0.84 (2) 1.95 (2) 2.788 (2) 174.45 (3)

Symmetry codes: (i) xþ2;yþ1;z; (ii) xþ2;yþ1;zþ1; (iii)

xþ1;yþ2;zþ1; (iv)xþ3;yþ1;z.

All H atoms were found in a difference Fourier map and refined freely.

Data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1991); cell refinement:MSC/AFC Diffractometer Control Software; data reduction: TEXSAN (Mole-cular Structure Corporation, 1999); program(s) used to solve struc-ture: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII(Johnson, 1976) andPLATON(Spek, 2003); software used to prepare material for publication:SHELXL97.

The authors gratefully acknowledge financial support from the Kırıkkale University Research Fund.

References

Albertsson, J., Grenthe, I. & Herbertsson, H. (1973).Acta Cryst.B29, 1855– 1860.

Chiari, G. & Ferraris, G. (1982).Acta Cryst.B38, 2331–2341.

Evans, M. B. J., Kapitan, A., Rosair, G. M., Roberts, K. J. & White, G. (2001). Acta Cryst.C57, 1277–1278.

Johnson, C. K. (1976).ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.

Molecular Structure Corporation (1991).MSC/AFC Diffractometer Control Software. MSC, 3200 Research Forest Drive, The Woodlands, TX 77381, USA.

Molecular Structure Corporation (1999).TEXSAN. Version 1.10. MSC, 9009 New Trails Drive, The Woodlands, TX 77381-5209, USA.

Ptasiewicz-Bak, H. & Leciejewicz, J. (1997a).Pol. J. Chem.71, 493–500. Ptasiewicz-Bak, H. & Leciejewicz, J. (1997b).Pol. J. Chem.71, 1603–1610. Sheldrick, G. M. (1990).Acta Cryst.A46, 467–473.

Sheldrick, G. M. (1997).SHELXL97. University of Go¨ttingen, Germany. Speakman, J. C. (1972).Struct. Bonding (Berlin),12, 141–199.

Spek, A. L. (2003).J. Appl. Cryst.36, 7–13.

Starosta, W. & Leciejewicz, J. (2005).J. Coord. Chem.58, 963–968. Takusagawa, T. & Shimada, A. (1973).Chem. Lett.pp. 1121–1126.

metal-organic papers

Acta Cryst.(2006). E62, m945–m947 Tombulet al. [Na(C

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supporting information

sup-1 Acta Cryst. (2006). E62, m945–m947

supporting information

Acta Cryst. (2006). E62, m945–m947 [https://doi.org/10.1107/S1600536806008130]

Poly[

µ

-aqua-aqua-

µ

-3-carboxypyrazine-2-carboxylato-sodium(I)]

Mustafa Tombul, Kutalm

ış

G

ü

ven and Naz

ı

m Alk

ış

Poly[\-m-aqua-aqua-µ-3-carboxypyrazine-2-carboxylato-sodium(I)]

Crystal data

[Na(C6H3N2O4)(H2O)2]

Mr = 226.13

Triclinic, P1 Hall symbol: -P 1

a = 7.8581 (14) Å

b = 8.4416 (19) Å

c = 7.602 (2) Å

α = 108.05 (3)°

β = 93.71 (2)°

γ = 70.139 (14)°

V = 450.45 (19) Å3

Z = 2

F(000) = 232

Dx = 1.667 Mg m−3

Mo radiation, λ = 0.71069 Å Cell parameters from 25 reflections

θ = 10.3–18.3°

µ = 0.19 mm−1

T = 295 K Prism, colourless 0.4 × 0.4 × 0.2 mm

Data collection

Rigaku AFC-7S diffractometer

Radiation source: fine-focus sealed tube Graphite monochromator

ω/2θ scans

Absorption correction: ψ scan

(MSC/AFC Diffractometer Control Software; Molecular Structure Corporation, 1991)

Tmin = 0.928, Tmax = 0.963 2737 measured reflections

2561 independent reflections 2171 reflections with I > 2σ(I)

Rint = 0.007

θmax = 30.0°, θmin = 2.7°

h = 0→10

k = −11→11

l = −10→10

3 standard reflections every 150 reflections intensity decay: 0.1%

Refinement

Refinement on F2 Least-squares matrix: full

R[F2 > 2σ(F2)] = 0.029

wR(F2) = 0.089

S = 1.03 2561 reflections 164 parameters 0 restraints

Primary atom site location: structure-invariant direct methods

Secondary atom site location: difference Fourier map

Hydrogen site location: inferred from neighbouring sites

All H-atom parameters refined

w = 1/[σ2(F

o2) + (0.1279P)2 + 0.6038P] where P = (Fo2 + 2Fc2)/3

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supporting information

sup-2 Acta Cryst. (2006). E62, m945–m947

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.

All H atoms were located from a difference Fourier synthesis map for the structure. They were refined with a rotating model, with Uiso values 1.5 times those of the attached atoms.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

x y z Uiso*/Ueq

Na1 0.97622 (6) 0.64028 (6) 0.22505 (6) 0.02584 (12)

O1 0.79734 (12) 0.45813 (11) 0.25491 (11) 0.02530 (17)

O2 1.20465 (11) 0.71143 (12) 0.08883 (11) 0.02787 (18)

O3 1.16355 (12) 0.35439 (11) 0.06391 (12) 0.02768 (18)

O4 0.99969 (12) 0.74130 (11) 0.54513 (11) 0.0323 (2)

O5 0.82941 (14) 0.90906 (12) 0.80501 (12) 0.0372 (2)

C1 0.87549 (15) 0.87414 (13) 0.64057 (14) 0.0226 (2)

C2 0.76445 (14) 1.00726 (13) 0.54464 (13) 0.02005 (19)

N1 0.54326 (13) 1.28835 (12) 0.56208 (13) 0.0264 (2)

N2 0.77081 (14) 0.95409 (12) 0.35922 (13) 0.0276 (2)

C3 0.65340 (13) 1.17601 (13) 0.64532 (13) 0.01980 (19)

C4 0.55027 (17) 1.23306 (16) 0.37675 (16) 0.0306 (2)

C5 0.66546 (19) 1.06815 (16) 0.27621 (15) 0.0325 (3)

C6 1.35008 (14) 0.75012 (13) 0.14636 (14) 0.02121 (19)

O6 1.47951 (12) 0.71939 (14) 0.04803 (12) 0.0373 (2)

H4 0.473 (2) 1.313 (2) 0.315 (2) 0.037 (4)*

H6 0.665 (2) 1.032 (2) 0.146 (3) 0.044 (5)*

H1 1.212 (3) 0.659 (3) −0.036 (3) 0.070 (6)*

H2 0.696 (3) 0.513 (3) 0.308 (2) 0.042 (5)*

H3 1.165 (2) 0.274 (3) 0.101 (2) 0.040 (4)*

H5 0.862 (3) 0.393 (3) 0.325 (3) 0.052 (5)*

H7 1.273 (3) 0.333 (3) 0.036 (3) 0.054 (5)*

Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23

Na1 0.0288 (2) 0.0229 (2) 0.0211 (2) −0.00581 (17) 0.00212 (16) 0.00281 (16)

O1 0.0234 (4) 0.0270 (4) 0.0207 (3) −0.0028 (3) 0.0000 (3) 0.0068 (3)

O2 0.0289 (4) 0.0357 (4) 0.0192 (3) −0.0156 (3) 0.0009 (3) 0.0031 (3)

O3 0.0238 (4) 0.0258 (4) 0.0323 (4) −0.0033 (3) 0.0035 (3) 0.0119 (3)

O4 0.0349 (5) 0.0257 (4) 0.0239 (4) 0.0041 (3) −0.0013 (3) 0.0066 (3)

O5 0.0553 (6) 0.0265 (4) 0.0228 (4) −0.0004 (4) 0.0064 (4) 0.0114 (3)

C1 0.0276 (5) 0.0182 (4) 0.0204 (4) −0.0057 (4) −0.0026 (4) 0.0065 (3)

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supporting information

sup-3 Acta Cryst. (2006). E62, m945–m947

N1 0.0269 (5) 0.0232 (4) 0.0231 (4) −0.0006 (3) −0.0009 (3) 0.0076 (3)

N2 0.0367 (5) 0.0220 (4) 0.0182 (4) −0.0037 (4) −0.0010 (3) 0.0047 (3)

C3 0.0200 (4) 0.0207 (4) 0.0178 (4) −0.0058 (3) 0.0004 (3) 0.0056 (3)

C4 0.0357 (6) 0.0275 (5) 0.0240 (5) −0.0030 (4) −0.0058 (4) 0.0110 (4)

C5 0.0455 (7) 0.0275 (5) 0.0179 (5) −0.0049 (5) −0.0038 (4) 0.0068 (4)

C6 0.0214 (5) 0.0199 (4) 0.0192 (4) −0.0031 (3) 0.0010 (3) 0.0056 (3)

O6 0.0255 (4) 0.0561 (6) 0.0260 (4) −0.0118 (4) 0.0067 (3) 0.0071 (4)

Geometric parameters (Å, º)

Na1—O4 2.3333 (12) O5—C1 1.2402 (14)

Na1—O3 2.3407 (12) C1—C2 1.5216 (14)

Na1—O2 2.4523 (10) C2—N2 1.3388 (14)

Na1—O1 2.4734 (10) C2—C3 1.3938 (14)

Na1—N2 2.5093 (13) N1—C3 1.3387 (13)

Na1—Na1i 3.4637 (16) N1—C4 1.3381 (15)

O1—H2 0.83 (2) N2—C5 1.3333 (15)

O1—H5 0.89 (2) C3—C6ii 1.5097 (15)

O2—C6 1.3055 (13) C4—C5 1.3840 (17)

O2—H1 0.91 (2) C4—H4 0.964 (17)

O3—H3 0.807 (19) C5—H6 0.938 (18)

O3—H7 0.84 (2) C6—O6 1.2081 (14)

O4—C1 1.2570 (14)

O4—Na1—O3 118.02 (4) Na1—O3—H3 118.1 (13)

O4—Na1—O3i 155.20 (4) Na1i—O3—H3 116.2 (12)

O3—Na1—O3i 86.07 (4) Na1—O3—H7 121.4 (14)

O4—Na1—O2 105.90 (4) Na1i—O3—H7 102.0 (13)

O3—Na1—O2 80.13 (4) H3—O3—H7 104.2 (18)

O3i—Na1—O2 82.79 (4) C1—O4—Na1 119.33 (7)

O4—Na1—O1 92.02 (4) O5—C1—O4 127.56 (10)

O3—Na1—O1 78.04 (4) O5—C1—C2 115.25 (9)

O3i—Na1—O1 87.15 (4) O4—C1—C2 117.17 (9)

O2—Na1—O1 156.50 (3) N2—C2—C3 120.89 (9)

O4—Na1—N2 68.81 (4) N2—C2—C1 117.61 (9)

O3—Na1—N2 172.79 (4) C3—C2—C1 121.44 (9)

O3i—Na1—N2 87.42 (4) C3—N1—C4 116.59 (10)

O2—Na1—N2 96.00 (4) C5—N2—C2 117.27 (10)

O1—Na1—N2 104.74 (4) C5—N2—Na1 130.49 (8)

O4—Na1—Na1i 161.05 (3) C2—N2—Na1 112.17 (7)

O3—Na1—Na1i 43.68 (3) N1—C3—C2 121.81 (9)

O3i—Na1—Na1i 42.39 (3) N1—C3—C6ii 114.39 (9)

O2—Na1—Na1i 78.30 (3) C2—C3—C6ii 123.78 (9)

O1—Na1—Na1i 79.95 (3) N1—C4—C5 121.73 (10)

N2—Na1—Na1i 129.74 (4) N1—C4—H4 117.6 (10)

Na1—O1—H2 116.0 (13) C5—C4—H4 120.7 (10)

Na1—O1—H5 105.2 (12) N2—C5—C4 121.64 (10)

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supporting information

sup-4 Acta Cryst. (2006). E62, m945–m947

C6—O2—Na1 135.32 (7) C4—C5—H6 119.8 (11)

C6—O2—H1 111.4 (14) O6—C6—O2 124.80 (10)

Na1—O2—H1 108.6 (14) O6—C6—C3ii 122.84 (10)

Na1—O3—Na1i 93.93 (4) O2—C6—C3ii 112.15 (9)

O4—Na1—O2—C6 18.68 (11) C3—C2—N2—Na1 −178.03 (8)

O3—Na1—O2—C6 −97.82 (10) C1—C2—N2—Na1 −0.88 (12)

O3i—Na1—O2—C6 174.94 (10) O4—Na1—N2—C5 175.15 (12)

O1—Na1—O2—C6 −119.69 (11) O3i—Na1—N2—C5 −12.08 (12)

N2—Na1—O2—C6 88.31 (11) O2—Na1—N2—C5 70.39 (12)

Na1i—Na1—O2—C6 −142.29 (10) O1—Na1—N2—C5 −98.45 (12)

O4—Na1—O3—Na1i 173.79 (4) Na1i—Na1—N2—C5 −9.36 (13)

O3i—Na1—O3—Na1i 0.0 O4—Na1—N2—C2 −8.05 (8)

O2—Na1—O3—Na1i −83.35 (4) O3i—Na1—N2—C2 164.72 (8)

O1—Na1—O3—Na1i 87.91 (4) O2—Na1—N2—C2 −112.81 (8)

O3—Na1—O4—C1 −163.55 (8) O1—Na1—N2—C2 78.35 (8)

O3i—Na1—O4—C1 1.56 (15) Na1i—Na1—N2—C2 167.44 (7)

O2—Na1—O4—C1 109.34 (9) C4—N1—C3—C2 −2.53 (16)

O1—Na1—O4—C1 −86.03 (9) C4—N1—C3—C6ii 175.80 (10)

N2—Na1—O4—C1 19.00 (9) N2—C2—C3—N1 3.03 (16)

Na1i—Na1—O4—C1 −150.25 (10) C1—C2—C3—N1 −174.01 (10)

Na1—O4—C1—O5 151.95 (10) N2—C2—C3—C6ii −175.15 (10)

Na1—O4—C1—C2 −26.61 (13) C1—C2—C3—C6ii 7.82 (15)

O5—C1—C2—N2 −161.00 (11) C3—N1—C4—C5 0.01 (19)

O4—C1—C2—N2 17.74 (15) C2—N2—C5—C4 −1.74 (19)

O5—C1—C2—C3 16.13 (15) Na1—N2—C5—C4 174.92 (10)

O4—C1—C2—C3 −165.13 (10) N1—C4—C5—N2 2.2 (2)

C3—C2—N2—C5 −0.76 (17) Na1—O2—C6—O6 151.40 (10)

C1—C2—N2—C5 176.38 (11) Na1—O2—C6—C3ii −23.45 (14)

Symmetry codes: (i) −x+2, −y+1, −z; (ii) −x+2, −y+2, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A D—H H···A D···A D—H···A

O2—H1···O1i 0.91 (2) 1.66 (2) 2.563 (1) 168.18 (3)

O1—H5···O4iii 0.89 (1) 1.79 (1) 2.671 (1) 176.61 (3)

O1—H2···N1iv 0.83 (2) 2.11 (2) 2.902 (2) 164.67 (3)

O3—H3···O5iii 0.81 (2) 1.88 (2) 2.688 (2) 177.33 (3)

O3—H7···O6v 0.84 (2) 1.95 (2) 2.788 (2) 174.45 (3)

Figure

Figure 1
Table 2Hydrogen-bond geometry (A˚ , �).

References

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