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Acta Cryst. (2009). E65, m1265-m1266    [ doi:10.1107/S1600536809038756 ]

Synchrotron study of poly[[di-[mu]-aqua([mu]-2,2'-bipyridyl-5,5'-dicarboxylato)dipotassium] dihydrate]

J. A. Bertke, A. G. Oliver and K. W. Henderson

Abstract top

The title compound, {[K2(C12H6N2O4)(H2O)2]·2H2O}n, forms a three-dimensional coordination polymer in the solid state. The asymmetric unit consists of one K+ ion, half of a 2,2'-bipyridyl-5,5'-dicarboxylate ligand, one coordinated water molecule and one solvent water molecule. The K+ ion is 7-coordinated by the oxygen atoms of two water molecules and by five oxygen atoms of four carboxylate groups, one of which is chelating. The extended structure can be described as a binodal network in which each K+ is a six-connected node, bonding to four carboxylate groups and two bridging water molecules, and the 2,2'-bipyridyl-5,5'-dicarboxylate linkers are eight-connected nodes, with each carboxylate group bridging four metal centers. Overall, this arrangement generates a complex network with point symbol {34.412.512}{34.44.54.63}2. Both of the bridging water molecules participate as donors in hydrogen-bonding interactions; one to solvent water molecules and a second to an oxygen atom of a carboxylate group.

Comment top

We are interested in using pre-assembled and structurally well defined aggregates as secondary building units (SBUs) to build coordination polymers or metal-organic frameworks (MOFs) (MacDougall et al., 2005). The title compound was synthesized as a precursor for use as a linker in the construction of MOFs. The 2,2'-bipyridyl-5,5'-dicarboxylate ligand has been used as a linear linker for a variety of MOFs (Finn & Zubieta, 2002; Schoknecht & Kempe, 2004); Szeto et al., 2008). It is a particularly interesting linker due to the fact that the pyridyl N atoms have the ability to act as Lewis bases for binding metal centers (Szeto et al., 2008).

The asymmetric unit consists of one K+ ion, half of a 2,2'-bipyridyl-5,5'-dicarboxylate ligand, one coordinated water molecule and one solvent water molecule (Fig. 1). The extended crystal structure of the title compound is composed of two-dimensional sheets consisting of potassium-carboxylate and potassium-water interactions. These sheets extend parallel to (001). The three-dimensional assembly is completed by connection of the sheets through the 2,2'-bipyridyl linkers (Fig. 2). Small channels run along the a axis and contain the disordered solvent water molecules. The geometry around the seven-coordinate potassium metal center can be described as a distorted monocapped trigonal-prism. The faces deviate from the ideal triangular, with angles of 49.69°(O1—O3—O2), 61.19° (O2—O1—O3) and 69.10° (O1—O2—O3). There is also a short contact distance of 2.826 (6) Å between O4 and N1, which is most likely due to a hydrogen bonding interaction. However, the hydrogen atoms on the solvent water molecule could not be located in the difference map.

For the topological analysis of the structure, the program TOPOS was used (Blatov, 2007). There has been only one structural example of the 2,2'-bipyridyl-5,5'-dicarboxylate ligand bound to an alkali metal reported, viz. Rb (Hafizovic et al., 2007).

Related literature top

For topological analysis, see: Blatov (2007). For background to metal-organic frameworks (MOFs), see: MacDougall et al. (2005). The 2,2'-bipyridyl-5,5'-dicarboxylate ligand has been used as a linear linker for a variety of MOFs, see: Finn & Zubieta, (2002); Schoknecht & Kempe (2004); Szeto et al., (2008). It is a particularly interesting linker due to the fact that the pyridyl N atoms have the ability to act as Lewis bases for binding metal centers (Szeto et al., 2008). There has been only one structural example of this ligand bound to an alkali metal reported, viz. Rb (Hafizovic et al., 2007). For synthetic details, see: Anderson et al. (1985).

Experimental top

The title complex was prepared using a modification of the method of Seddon and Pilling (Anderson et al., 1985) for the preparation of 2,2'-bipyridyl-4,4'-dicarboxylic acid. 5,5'-dimethyl-2,2'-bipyridine and K[MnO4] were purchased from Aldrich and used without further purification. 1H NMR data were collected on a Varian Unity Plus 300 spectrometer at 298 K. K[MnO4] (10 g, 63 mmol) was added to a solution of 5,5'-dimethyl-2,2'-bipyridine (1.6 g, 8.7 mmol) in 100 mL H2O. The mixture was heated to reflux for 12 h. Upon cooling, the mixture was filtered and the black precipitate was washed with water (2x 30 mL). The filtrate and the washings were combined and extracted with diethyl ether to remove unreacted starting material. The aqueous fraction was collected and the solvent was removed under vacuum, leaving a sticky white solid. The solid was heated under vacuum at 373 K overnight to give a fine white powder. Single crystals were grown from an aqueous solution upon slow evaporation of the solvent.

Refinement top

Hydrogen atoms were placed at calculated positions and allowed to ride on the position of the parent atom, with the exception of those on the coordinated O3 water molecule which were located in the difference fourier map. H atoms of the uncoordinated water molecule O4 could not be located unambiguously and were eventually excluded from the refinement.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL (Sheldrick, 2008b).

Figures top
[Figure 1] Fig. 1. A portion of the polymeric structure of the title compound. All hydrogen atoms except those located on O3 have been omitted. Thermal ellipsoids are shown at the 50% probablility level.
[Figure 2] Fig. 2. Thermal ellipsoid plot of the asymmetric unit of the title compound. Thermal ellipsoids are shown at the 50% probablility level.
poly[[di-µ-aqua(µ-2,2'-bipyridyl-5,5'-dicarboxylato)dipotassium] dihydrate] top
Crystal data top
[K2(C12H6N2O4)(H2O)2]·2H2OF(000) = 404
Mr = 392.46Dx = 1.646 Mg m−3
Monoclinic, P21/cSynchrotron radiation, λ = 0.77490 Å
Hall symbol: -P 2ycCell parameters from 1984 reflections
a = 3.6769 (6) Åθ = 2.8–27.6°
b = 8.2042 (14) ŵ = 0.76 mm−1
c = 26.292 (4) ÅT = 150 K
β = 92.924 (2)°Plate, colorless
V = 792.1 (2) Å30.04 × 0.03 × 0.01 mm
Z = 2
Data collection top
Bruker APEXII
diffractometer		1622 independent reflections
Radiation source: synchrotron1301 reflections with I > 2σ(I)
channel-cut Si-<111> crystalRint = 0.045
Detector resolution: 83.33 pixels mm-1θmax = 29.0°, θmin = 2.8°
ω and φ scansh = −4→4
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)		k = −10→10
Tmin = 0.654, Tmax = 0.746l = −32→32
8561 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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.128H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.0609P)2 + 1.2501P]
where P = (Fo2 + 2Fc2)/3
1622 reflections(Δ/σ)max < 0.001
117 parametersΔρmax = 1.03 e Å−3
0 restraintsΔρmin = −0.51 e Å−3
Crystal data top
[K2(C12H6N2O4)(H2O)2]·2H2OV = 792.1 (2) Å3
Mr = 392.46Z = 2
Monoclinic, P21/cSynchrotron radiation, λ = 0.77490 Å
a = 3.6769 (6) ŵ = 0.76 mm−1
b = 8.2042 (14) ÅT = 150 K
c = 26.292 (4) Å0.04 × 0.03 × 0.01 mm
β = 92.924 (2)°
Data collection top
Bruker APEXII
diffractometer		1622 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)		1301 reflections with I > 2σ(I)
Tmin = 0.654, Tmax = 0.746Rint = 0.045
8561 measured reflectionsθmax = 29.0°
Refinement top
R[F2 > 2σ(F2)] = 0.045H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.128Δρmax = 1.03 e Å−3
S = 1.08Δρmin = −0.51 e Å−3
1622 reflectionsAbsolute structure: ?
117 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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*/Ueq
K10.06233 (18)0.72796 (8)0.22289 (2)0.0250 (2)
O10.5909 (6)0.7368 (3)0.30066 (8)0.0257 (5)
O20.4216 (6)0.4762 (3)0.29578 (8)0.0262 (5)
O30.5493 (7)0.5466 (3)0.16339 (11)0.0359 (6)
H3A0.499 (13)0.454 (6)0.1748 (18)0.052 (14)*
H3B0.528 (16)0.539 (7)0.132 (2)0.080 (19)*
O40.537 (2)0.0661 (6)0.44962 (17)0.154 (3)
N10.7659 (7)0.3947 (3)0.44667 (10)0.0272 (6)
C10.9350 (8)0.5168 (4)0.47310 (10)0.0216 (6)
C20.6527 (8)0.4234 (4)0.39788 (11)0.0251 (7)
H2A0.53520.33750.37920.030*
C30.6981 (8)0.5704 (4)0.37364 (11)0.0225 (6)
C40.8744 (8)0.6938 (4)0.40162 (11)0.0252 (7)
H4A0.91380.79680.38630.030*
C50.9916 (8)0.6669 (4)0.45143 (11)0.0209 (6)
H5A1.11060.75100.47070.025*
C60.5582 (8)0.5960 (4)0.31898 (11)0.0200 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
K10.0231 (3)0.0293 (4)0.0222 (4)−0.0001 (3)−0.0021 (2)0.0022 (3)
O10.0312 (12)0.0272 (12)0.0182 (10)0.0001 (9)−0.0035 (9)0.0015 (8)
O20.0310 (12)0.0258 (12)0.0209 (10)−0.0008 (9)−0.0053 (9)−0.0028 (9)
O30.0432 (15)0.0268 (14)0.0371 (16)−0.0043 (11)−0.0035 (12)0.0001 (11)
O40.345 (9)0.055 (3)0.059 (3)0.017 (4)−0.009 (4)−0.001 (2)
N10.0293 (14)0.0311 (15)0.0209 (13)−0.0025 (11)−0.0025 (11)−0.0005 (11)
C10.0182 (13)0.0305 (16)0.0159 (14)0.0023 (12)−0.0013 (11)−0.0020 (12)
C20.0250 (16)0.0316 (17)0.0183 (14)0.0008 (13)−0.0024 (12)−0.0005 (12)
C30.0176 (14)0.0330 (16)0.0168 (14)0.0038 (12)0.0003 (11)−0.0008 (12)
C40.0225 (15)0.0325 (17)0.0205 (15)0.0018 (12)−0.0003 (11)−0.0004 (12)
C50.0200 (14)0.0256 (15)0.0167 (14)−0.0018 (11)−0.0040 (11)−0.0009 (11)
C60.0181 (14)0.0261 (16)0.0158 (14)0.0029 (11)0.0002 (11)−0.0014 (11)
Geometric parameters (Å, °) top
K1—O2i2.732 (2)N1—C21.349 (4)
K1—O1ii2.748 (2)N1—C11.353 (4)
K1—O12.749 (2)C1—C51.376 (4)
K1—O3ii2.814 (3)C1—C1iv1.496 (6)
K1—O2iii2.843 (2)C2—C31.378 (5)
K1—O32.855 (3)C2—H2A0.9500
K1—O23.070 (2)C3—C41.392 (4)
O1—C61.259 (4)C3—C61.516 (4)
O2—C61.249 (4)C4—C51.376 (4)
O3—H3A0.84 (5)C4—H4A0.9500
O3—H3B0.84 (6)C5—H5A0.9500
O2i—K1—O1ii71.60 (7)K1vi—O2—K197.69 (6)
O2i—K1—O1122.90 (7)K1vii—O2—K1130.08 (8)
O1ii—K1—O183.96 (6)K1v—O3—K180.87 (7)
O2i—K1—O3ii83.24 (8)K1v—O3—H3A116 (3)
O1ii—K1—O3ii89.84 (8)K1—O3—H3A97 (3)
O1—K1—O3ii148.85 (8)K1v—O3—H3B129 (4)
O2i—K1—O2iii82.49 (6)K1—O3—H3B124 (4)
O1ii—K1—O2iii124.15 (7)H3A—O3—H3B106 (5)
O1—K1—O2iii69.93 (6)C2—N1—C1118.1 (3)
O3ii—K1—O2iii135.82 (8)N1—C1—C5121.7 (3)
O2i—K1—O3135.30 (8)N1—C1—C1iv117.7 (3)
O1ii—K1—O3149.13 (8)C5—C1—C1iv120.6 (3)
O1—K1—O388.96 (7)N1—C2—C3123.6 (3)
O3ii—K1—O380.87 (7)N1—C2—H2A118.2
O2iii—K1—O380.56 (7)C3—C2—H2A118.2
O2i—K1—O2150.35 (3)C2—C3—C4117.2 (3)
O1ii—K1—O279.68 (6)C2—C3—C6121.1 (3)
O1—K1—O244.61 (6)C4—C3—C6121.7 (3)
O3ii—K1—O2104.26 (7)C5—C4—C3120.0 (3)
O2iii—K1—O2108.66 (3)C5—C4—H4A120.0
O3—K1—O274.31 (7)C3—C4—H4A120.0
C6—O1—K1v109.68 (18)C4—C5—C1119.4 (3)
C6—O1—K1100.52 (17)C4—C5—H5A120.3
K1v—O1—K183.96 (6)C1—C5—H5A120.3
C6—O2—K1vi156.4 (2)O2—C6—O1125.4 (3)
C6—O2—K1vii113.13 (18)O2—C6—C3117.5 (3)
K1vi—O2—K1vii82.49 (6)O1—C6—C3117.1 (3)
C6—O2—K185.69 (17)
O2i—K1—O1—C6134.52 (17)K1vi—O2—C6—K1−99.4 (5)
O1ii—K1—O1—C671.04 (18)K1vii—O2—C6—K1132.06 (13)
O3ii—K1—O1—C6−8.6 (3)K1vi—O2—C6—K1v−163.2 (4)
O2iii—K1—O1—C6−159.19 (19)K1vii—O2—C6—K1v68.29 (14)
O3—K1—O1—C6−78.86 (18)K1—O2—C6—K1v−63.77 (7)
O2—K1—O1—C6−10.37 (16)K1vi—O2—C6—K1vii128.6 (5)
C6ii—K1—O1—C650.56 (15)K1—O2—C6—K1vii−132.06 (13)
C6iii—K1—O1—C6−169.28 (16)K1v—O1—C6—O2−64.9 (3)
K1ii—K1—O1—C671.04 (18)K1—O1—C6—O222.4 (3)
K1v—K1—O1—C6−108.96 (18)K1v—O1—C6—C3114.8 (2)
O2i—K1—O1—K1v−116.52 (7)K1—O1—C6—C3−157.9 (2)
O1ii—K1—O1—K1v180.0K1v—O1—C6—K1−87.29 (11)
O3ii—K1—O1—K1v100.40 (15)K1—O1—C6—K1v87.29 (11)
O2iii—K1—O1—K1v−50.23 (6)K1v—O1—C6—K1vii−4.1 (3)
O3—K1—O1—K1v30.09 (7)K1—O1—C6—K1vii83.2 (2)
O2—K1—O1—K1v98.58 (9)C2—C3—C6—O2−4.5 (4)
C6—K1—O1—K1v108.96 (18)C4—C3—C6—O2176.1 (3)
C6ii—K1—O1—K1v159.52 (7)C2—C3—C6—O1175.8 (3)
C6iii—K1—O1—K1v−60.32 (6)C4—C3—C6—O1−3.7 (4)
K1ii—K1—O1—K1v180.0C2—C3—C6—K1108.6 (6)
O2i—K1—O2—C6−67.1 (2)C4—C3—C6—K1−70.9 (7)
O1ii—K1—O2—C6−81.54 (17)C2—C3—C6—K1v−125.9 (3)
O1—K1—O2—C610.31 (16)C4—C3—C6—K1v54.7 (4)
O3ii—K1—O2—C6−168.72 (17)C2—C3—C6—K1vii−47.7 (3)
O2iii—K1—O2—C641.19 (16)C4—C3—C6—K1vii132.8 (3)
O3—K1—O2—C6115.25 (18)O2i—K1—C6—O2138.37 (12)
C6ii—K1—O2—C6−94.85 (18)O1ii—K1—C6—O293.78 (17)
C6iii—K1—O2—C637.2 (2)O1—K1—C6—O2−160.9 (3)
K1ii—K1—O2—C6−116.44 (16)O3ii—K1—C6—O213.6 (2)
K1v—K1—O2—C663.56 (16)O2iii—K1—C6—O2−141.38 (15)
O2i—K1—O2—K1vi89.41 (15)O3—K1—C6—O2−60.97 (17)
O1ii—K1—O2—K1vi75.00 (7)C6ii—K1—C6—O274.81 (17)
O1—K1—O2—K1vi166.84 (12)C6iii—K1—C6—O2−149.60 (19)
O3ii—K1—O2—K1vi−12.18 (9)K1ii—K1—C6—O274.81 (17)
O2iii—K1—O2—K1vi−162.27 (8)K1v—K1—C6—O2−105.19 (17)
O3—K1—O2—K1vi−88.21 (8)O2i—K1—C6—O1−60.7 (2)
C6—K1—O2—K1vi156.5 (2)O1ii—K1—C6—O1−105.34 (19)
C6ii—K1—O2—K1vi61.68 (7)O3ii—K1—C6—O1174.51 (17)
C6iii—K1—O2—K1vi−166.30 (7)O2iii—K1—C6—O119.50 (18)
K1ii—K1—O2—K1vi40.09 (7)O3—K1—C6—O199.91 (18)
K1v—K1—O2—K1vi−139.91 (7)O2—K1—C6—O1160.9 (3)
O2i—K1—O2—K1vii176.04 (11)C6ii—K1—C6—O1−124.31 (16)
O1ii—K1—O2—K1vii161.63 (11)C6iii—K1—C6—O111.28 (17)
O1—K1—O2—K1vii−106.52 (13)K1ii—K1—C6—O1−124.31 (16)
O3ii—K1—O2—K1vii74.45 (11)K1v—K1—C6—O155.69 (16)
O2iii—K1—O2—K1vii−75.64 (13)O2i—K1—C6—C317.7 (6)
O3—K1—O2—K1vii−1.58 (10)O1ii—K1—C6—C3−26.9 (6)
C6—K1—O2—K1vii−116.8 (2)O1—K1—C6—C378.4 (6)
C6ii—K1—O2—K1vii148.31 (12)O3ii—K1—C6—C3−107.0 (6)
C6iii—K1—O2—K1vii−79.67 (12)O2iii—K1—C6—C397.9 (6)
K1ii—K1—O2—K1vii126.73 (8)O3—K1—C6—C3178.4 (6)
K1v—K1—O2—K1vii−53.28 (8)O2—K1—C6—C3−120.7 (7)
O2i—K1—O3—K1v109.38 (9)C6ii—K1—C6—C3−45.9 (6)
O1ii—K1—O3—K1v−105.92 (13)C6iii—K1—C6—C389.7 (6)
O1—K1—O3—K1v−29.55 (7)K1ii—K1—C6—C3−45.9 (6)
O3ii—K1—O3—K1v180.0K1v—K1—C6—C3134.1 (6)
O2iii—K1—O3—K1v40.27 (6)O2i—K1—C6—K1v−116.44 (9)
O2—K1—O3—K1v−72.29 (7)O1ii—K1—C6—K1v−161.03 (6)
C6—K1—O3—K1v−51.77 (7)O1—K1—C6—K1v−55.69 (16)
C6ii—K1—O3—K1v−107.38 (9)O3ii—K1—C6—K1v118.82 (8)
C6iii—K1—O3—K1v56.64 (7)O2iii—K1—C6—K1v−36.19 (6)
K1ii—K1—O3—K1v180.0O3—K1—C6—K1v44.22 (6)
C2—N1—C1—C50.1 (4)O2—K1—C6—K1v105.19 (17)
C2—N1—C1—C1iv−179.0 (3)C6ii—K1—C6—K1v180.0
C1—N1—C2—C3−0.4 (5)C6iii—K1—C6—K1v−44.41 (7)
N1—C2—C3—C40.7 (5)K1ii—K1—C6—K1v180.0
N1—C2—C3—C6−178.8 (3)O2i—K1—C6—K1vii173.13 (8)
C2—C3—C4—C5−0.7 (4)O1ii—K1—C6—K1vii128.54 (9)
C6—C3—C4—C5178.8 (3)O1—K1—C6—K1vii−126.1 (2)
C3—C4—C5—C10.4 (4)O3ii—K1—C6—K1vii48.39 (12)
N1—C1—C5—C4−0.1 (5)O2iii—K1—C6—K1vii−106.62 (8)
C1iv—C1—C5—C4179.0 (3)O3—K1—C6—K1vii−26.21 (8)
K1vi—O2—C6—O1−119.0 (4)O2—K1—C6—K1vii34.76 (13)
K1vii—O2—C6—O1112.4 (3)C6ii—K1—C6—K1vii109.57 (6)
K1—O2—C6—O1−19.7 (3)C6iii—K1—C6—K1vii−114.84 (11)
K1vi—O2—C6—C361.2 (6)K1ii—K1—C6—K1vii109.57 (6)
K1vii—O2—C6—C3−67.3 (3)K1v—K1—C6—K1vii−70.43 (6)
K1—O2—C6—C3160.6 (2)
Symmetry codes: (i) −x, y+1/2, −z+1/2; (ii) x−1, y, z; (iii) −x+1, y+1/2, −z+1/2; (iv) −x+2, −y+1, −z+1; (v) x+1, y, z; (vi) −x, y−1/2, −z+1/2; (vii) −x+1, y−1/2, −z+1/2.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O1vii0.84 (5)1.93 (5)2.770 (4)177 (5)
O3—H3B···O4iii0.84 (6)2.15 (6)2.976 (5)169 (5)
Symmetry codes: (vii) −x+1, y−1/2, −z+1/2; (iii) −x+1, y+1/2, −z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O1i0.84 (5)1.93 (5)2.770 (4)177 (5)
O3—H3B···O4ii0.84 (6)2.15 (6)2.976 (5)169 (5)
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x+1, y+1/2, −z+1/2.
Acknowledgements top

Samples for synchrotron crystallographic analysis were submitted through the SCrALS (Service Crystallography at Advanced Light Source) program. Crystallographic data were collected at Beamline 11.3.1 at the Advanced Light Source (ALS), Lawrence Berkeley National Laboratory. The ALS is supported by the US Department of Energy, Office of Energy Sciences, under contract DE—AC02–05CH11231.

references
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