Probing the supra­molecular inter­action synthons of 1-benzofuran-2,3-dicarboxylic acid in its monoanionic form

1-Benzofuran-2,3-dicarboxylic acid (C₁₀H₆O₅) is a dicarboxylic acid ligand which can readily engage in organometallic complexes with various metal ions. This ligand is characterized by an intra­molecular hydrogen bond between the two carboxyl residues, and, as a monoanionic species, readily forms supra­molecular adducts with different organic and inorganic cations. These are a 1:1 adduct with the dimethyl­ammonium cation, namely dimethyl­ammonium 3-carb­oxy-1-benzofuran-2-carboxyl­ate, C₂H₈N⁺·C₁₀H₅O₅⁻, (I), a 2:1 com­plex with Cu²⁺ ions in which four neutral imidazole mol­ecules also coordinate the metal atom, namely bis­(3-carb­oxy-1-ben­zo­furan-2-carboxyl­ato-κO³)tetra­kis(1H-imidazole-κN³)copper(II), [Cu(C₁₀H₅O₅)₂(C₃H₄N₂)₄], (II), and a 4:1 adduct with [La(H₂O)₇]³⁺ ions, namely hepta­aqua­bis(3-carb­oxy-1-benzofuran-2-carboxyl­ato-κO³)lanthanum 3-carb­oxy-1-ben­zo­furan-2-carboxyl­ate 1-benzofuran-2,3-dicarboxylic acid sol­vate tetrahydrate, [La(C₁₀H₅O₅)₂(H₂O)₇](C₁₀H₅O₅)·C₁₀H₆O₅·4H₂O, (III). In the crystal structure, complex (II) resides on inversion centres, while complex (III) resides on axes of twofold rotation. The crystal packing in all three structures reveals π–π stacking inter­actions between the planar aromatic benzofuran residues, as well as hydrogen bonding between the components. The significance of this study lies in the first crystallographic characterization of the title framework, which consistently exhibits the presence of an intra­molecular hydrogen bond and a consequent monoanionic-only nature. It shows further that the anion can coordinate readily to metal cations as a ligand, as well as acting as a monovalent counter-ion. Finally, the aromaticity of the flat benzofuran residue provides an additional supra­molecular synthon that directs and facilitates the crystal packing of compounds (I)–(III).

S1. Comment

Organic polycarboxylic acids can be considered as attractive building blocks for the construction of supramolecular architectures, because of their ability to link to metal centres in a variety of coordination modes simultaneously and generate extended networks. Moreover, such ligands can be readily deprotonated to balance the charge of the metal ions they interact with (and thus enjoy electrostatic attraction to the metal centres), without the need to incorporate foreign ions into the product. Several examples of materials with bifunctional anions, such as 1,4-benzenedicarboxylate (Guilera & Steed, 1999), trifunctional, such as 1,3,5-benzenetricarboxylate (Liu et al., 2007) or 1,3,5-cyclohexanetricarboxylate (Fang et al., 2006), tetrafunctional, such as 1,2,4,5-benzenetetracarboxylate (Ghosh & Bharadwaj, 2004) or 1,4,5,8-naphthalenetetracarboxylate (Koner & Goldberg, 2008), and hexafunctional, such as benzenehexacarboxylate (Yang et al., 2004), have been studied extensively in recent years. The tetra(carboxyphenyl)porphyrin ligand provides a particularly fascinating example of a tetracarboxylic acid prone to forming rigid open-framework solids via coordination polymerization through metal ions (Goldberg, 2005). In the above context, we focus in this study on the benzofuran-2,3-dicarboxylic building block (BFDC), aiming to explore for the first time (structures of neither the carboxylic acid form nor the carboxylate form of this compound have been reported previously) its structural features and possible synthons of supramolecular interaction with other components.

All three compounds (I)–(III) were obtained in mildly basic reaction environments used to promote the formation of metal–carboxylate coordination bonds. Although we failed to formulate coordination polymers at this stage, the present characterization of the crystalline products provided useful information. Thus, when the title dicarboxylic acid was reacted with a lanthanum nitrate salt (see below) in the presence of N,N'-dimethylformamide (DMF) in hydrothermal conditions, no metal ions were incorporated into the structure. Instead, the 1:1 salt, (I), formed between the mono-deprotonated benzofuran component (BFDC^-) and a dimethylammonium cation (a product resulting from hydrolysis of DMF). The observed molecular structure of BFDC^- in (I) throws light on the preferred form of this species in the other crystal structures as well, and deserves particular attention. Fig. 1 reveals that the spatial proximity of the two ortho-substituted carboxylic acid functions is favourable to the formation of an intramolecular O11—H11···O14 hydrogen bond (Table 1). Moreover, deprotonation occurs favourably on the carboxylic acid group (C13/O14/O15) which is closer to the electron-withdrawing etheral site. These features explain the preferred behaviour of this ligand. Although it bears two carboxylic acid functions, it tends to act as a monoprotic acid, the H atoms of the second acid group being engaged in an effective intramolecular hydrogen bond. In addition, hydrogen bonding also occurs between the ammonium cation and BFDC^- (Table 1).

The crystal structure of (I) is shown in Fig. 2(a). It reveals that centrosymmetric hydrogen-bonded dimers are formed with an R²₄(8) ring motif (Bernstein et al., 1995) involving two cations and two anions. The rigid benzofuran group O1/C2–C8/C12 is essentially planar with delocalized π-electron density. Not surprisingly, therefore, its intermolecular organization in the crystal structure involves π–π interactions between partly overlapping anions located at (x, y, z) and (-x, 2 - y, 1 - z) (Fig. 2b). The mean interplanar distance between the inversion-related O1/C2–C8/C12 fragments of these two species is 3.388 (7) Å, while the distance between the centres of the corresponding C2—C7 bonds is 3.492 (3) Å. Only minimal overlap occurs, however, between subsequent (along the a axis) parallel aromatic species related by inversion at (1/2, 1, 1/2).

Reaction of the dicarboxylic acid ligand with Cu^II ions, in the presence of imidazole, yielded compound (II), which represents an octahedral complex (Fig. 3) with four imidazole ligands occupying the equatorial positions and two BFDC^- anions coordinating to the axial positions. It resides on centres of inversion. The reaction of BFDC with the Cu^II ions has not affected the features observed in (I), namely the presence of an intramolecular hydrogen bond associated with monodeprotonation only. Correspondingly, the two BFDC^- ligating species balance the 2+ charge of the central metal ion. As commonly observed in the literature, the octahedral geometry of (II) is axially distorted due to the Jahn–Teller effect. The equatorial Cu1—N2 and Cu1—N7 bond lengths are 2.009 (2) and 2.015 (2) Å, while the axial Cu1—O12 bond lengths are 2.451 (2) Å. The stacking interactions between the aromatic benzofuran fragments are also evident in the crystal structure of (II) (Fig. 4). Adjacent inversion-related [at (1/2, 0, 1/2)] benzofuran fragments C15—C21/O22/C23 overlap one another at a mean interplanar distance of 3.424 (13) Å. Neighbouring units of the octahedral complex are also linked via hydrogen bonds between the NH sites of the imidazoles of one unit and the carboxylic acid fragment of adjacent anions (Table 2). The N—H···O bonds develop sheets of hydrogen-bonded molecules in the (101) plane (Fig. 4).

These molecular characteristics of BFDC/BFDC^- are also preserved in the reaction of BFDC with trivalent metal ions such as La³⁺. The molecular structure of the resulting [La(H₂O)₇(BFDC^-)₂].(BFDC^-) adduct, (III), is shown in Fig. 5. In spite of the high coordination number of this metal (9), only two monoanionic ligand species coordinate to it, possibly due to steric constraints. The coordination environment is completed by seven molecules of water. Units of the complex are positioned on twofold rotation axes (1/2 - x, 1/2 - y, z). The coordination distances are La1—O6(BFDC^-) = 2.511 (6) Å and La1—O(water) = 2.562 (2)–2.602 (6) Å. In order to balance the charge of the trivalent cation, an additional non-coordinated BFDC^- anion is incorporated into the structure between the aromatic fragments of adjacent entities of the lanthanum complex aligned along the b axis. Fig. 6 nicely illustrates the parallel alignment of the anionic ligands along the b axis of the crystal structure. Partial but significant overlap occurs between the C9/C10/O14/C15–C25 and C24/C25/O29/C30–C35 benzofuran fragments of the asymmetric unit, with a mean interplanar distance between them of 3.387 (9) Å. Minimal parallel overlap exists between the C24/C25/O29/C30–C35 framework at (x, y, z) and the adjacent C9/C10/O14/C15–C25 residue at (x, y - 1, z), the corresponding mean perpendicular distance between these planes being 3.124 (17) Å. Two molecules of disordered non-coordinated water per [La(H₂O)₇(BFDC^-)₂].(BFDC^-) unit are included in the interstitial voids in (III). The water ligands coordinated to La are involved in numerous hydrogen-bonding interactions with neighbouring entities, yielding an extended supramolecular pattern of three-dimensional connectivity (Table 3).

In summary, this study characterizes the molecular structure of the benzofuran dicarboxylic acid ligand, ellucidating its high propensity to react as a mono-anion, while maintaining an intramolecular hydrogen bond between the two carboxylic acid substituents. Consistent occurrence of the latter makes second deprotonation of BFDC^- less probable. The aromatic nature of BFDC^- is widely reflected in the intermolecular π–π stacking interactions observed in the three crystal structures presented here, with a nearly constant spacing of 3.37–3.42 Å between the overlapping benzofurans. Application of the BFDC ligand, as a bidentate or polydentate bridging ligand, in the synthesis of extended coordination polymers may require more extreme experimental conditions.

S2. Experimental

The title dicarboxylic acid, BFDC, as well as all the other reactants and solvents used, were obtained commercially.

Compound (I) was obtained by heating a mixture of La(NO₃)₃.6H₂O (0.130 g, 0.3 mmol), the BFDC acid (0.124 g, 0.6 mmol) and N,N'-dimethylformamide (DMF; 3 ml) in a sealed 5 ml reactor at 433 K for 48 h, followed by gradual cooling to ambient temperature. Colourless needles of (I) were collected by filtration and air-dried, without incorporation of any lanthanum ions. Needle-shaped crystals of (III) were obtained by a similar procedure, omitting the DMF component from the reaction mixture.

Blue crystals of (II) were obtained by the following procedure. A solution of Cu(NO₃)₂.2.5H₂O (0.058 g, 0.25 mmol) in H₂O (4 ml) was added to a suspension of the BFDC acid (0.052 g, 0.25 mmol) in H₂O (7 ml), followed by dropwise addition of imidazole (0.068 g, 1 mmol) in DMF (2 ml) under continuous stirring at about 333 K. The resulting blue-coloured mixture was cooled to room temperature and filtered. Crystals of (II) were obtained how?

S3. Refinement

The hydrogen atoms bound to C-atoms were located in calculated positions, and were constrained to ride on their parent atoms with C—H distances of 0.95 and 0.98 Å and with U_iso(H) = 1.2 and 1.5 U_eq(C), respectively. In (I), H-atoms bound to O and N were located in difference-Fourier maps. Their coordinates were included in the refinement, but assigned U_iso(H) = 1.2 U_eq(O/N). In (II), the H-atom bound to N(imidazole) was placed in calculated position at N—H = 0.88 Å, while the H-atom bound to O was located in a difference-Fourier map. The two atoms were assigned U_iso(H) = 1.2 U_eq(O/N), but their atomic parameters were not refined. In (III), the H-atoms bound to O3, O4, and O5 were located in difference-Fourier maps. Those attached to O2, O7 and O22 could not be located reliably; they were placed in calculated positions to optimize the O2···O28(at -x+3/4, y+1/4, z-1/4), O7···O12 and O22···O27 hydrogen bonds, respectively. Charge-balance considerations and the symmetry features of this structure required that the noncoordinated BFDC moiety is only partially deprotonated (i.e. deprotonation occurs in 50% of these fragments). The additional H atom (with 50% occupancy) bound to either O27 or O28 of the noncoordinated ligand could not be clearly located (though most probably it should be there) in difference Fourier maps. The corresponding O—H distances were then restrained to O—H = 0.90 (2)Å, and assigned U_iso(H) = 1.5 U_eq(O). Their atomic parameters were not refined in the final least-squares calculations. Nevertheless, presence of weak peaks of residual density between atoms O7 and O12 and O22 and O27 may indicate that the H-bond in these two species is partially delocalized. Compound (III) crystallized as a hydrate in the space group Fdd2 and represents a racemic twin. The water solvent incorporated into the crystal lattice could not be reliably characterized by discrete atoms (possibly due to its location on, and apparent disorder about, special positions). Conventional refinement with the solvent excluded converged at R1 = 0.071, the difference Fourier electron-density map revealing four significant peaks within 1.9–2.6 e ų related to the solvent. This relatively low R factor attests to the essential correctness of the main structural model in (III). The contribution of the water solvent was thus subtracted from the diffraction data by the SQUEEZE procedure in PLATON (Spek, 2003), which led to R1 = 0.049. These calculations showed that there are eight voids per cell of 200ų each. The residual electron count was assessed to be 304 e per cell, which corresponds nicely with four water molecules per void (two water species per asymmetric unit).

Computing details

For all compounds, data collection: COLLECT (Nonius, 1999); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. The molecular structure of compound (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level at ca 110 K, and H atoms are shown as small spheres of arbitrary radii. Intra- and intermolecular hydrogen bonds are indicated by dashed lines.
	Fig. 2. The crystal packing in (I). H atoms have been omitted for clarity. (a) A view of the crystal structure and the centrosymmetric hydrogen bonding of two anions and two cations around inversion at (1/2, 1/2, 1/2). The secondary N16—H16A···O1 hydrogen bond has been omitted. [Symmetry code: (i) 1 - x, 1 - y, 1 - z.] (b) The parallel overlap of the the anions related by inversion at (0, 1, 1/2). [Symmetry code: (i) -x, 2 - y, 1 - z.]
	Fig. 3. The molecular structure of compound (II), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level at ca 110 K. H atoms have been omitted, except for those involved in the intramolecular hydrogen bond (dashed lines). The octahedral complex is located on a centre of inversion at (0, 0, 0), and only atoms of the asymmetric unit are labelled.
	Fig. 4. The crystal packing in (II). The Cu^II ions of the octahedral coordination complexes are denoted by small spheres. Note the pairing (via partial π–π overlap) of the benzofuran units around inversion centres at (1/2, 0, 1/2), as well as the intermolecular hydrogen bonding (intra- and intermolecular hydrogen bonds are denoted by dashed lines) in the (101) plane of the crystal. H atoms have been omitted for clarity.
	Fig. 5. The molecular structure of compound (III), showing the atom-labelling scheme. The lanthanide ion La1 and coordinated water atom O2 reside on an axis of twofold rotation at (1/2 - x, 1/2 - y, z), and only atoms of the asymmetric unit are labelled. Displacement ellipsoids are drawn at the 50% probability level at ca 110 K. H atoms have been omitted, except for those involved in the intramolecular hydrogen bond (dashed lines). The disordered non-coordinated water solvent has also been omitted.
	Fig. 6. Molecules displaced along the b axis in (III), illustrating the dominant π–π stacking arrangement of the benzofuran fragments in the crystal structure. H atoms have been omitted for clarity. [Symmetry codes: (i) x,y + 1,z; (ii) x,y - 1,z.]

(I) Dimethylammonium 3-carboxy-1-benzofuran-2-carboxylate

Crystal data

C2H8N^+·C10H5O5^−	Z = 2
Mr = 251.23	F(000) = 264
Triclinic, P1	Dx = 1.433 Mg m^−3
a = 8.3381 (4) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.6806 (3) Å	Cell parameters from 2231 reflections
c = 8.8521 (5) Å	θ = 2.5–26.5°
α = 68.4693 (17)°	µ = 0.11 mm^−1
β = 78.8197 (17)°	T = 110 K
γ = 81.035 (4)°	Rod, colourless
V = 582.17 (5) Å^3	0.40 × 0.20 × 0.20 mm

Data collection

Nonius KappaCCD area-detector diffractometer	1822 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.047
Graphite monochromator	θmax = 26.5°, θmin = 2.5°
Detector resolution: 12.8 pixels mm^-1	h = −10→10
1 deg. ω scans	k = −10→10
7187 measured reflections	l = −11→10
2385 independent reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.116	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0573P)^2 + 0.1431P] where P = (Fo^2 + 2Fc^2)/3
2385 reflections	(Δ/σ)max < 0.001
174 parameters	Δρmax = 0.20 e Å^−3
0 restraints	Δρmin = −0.24 e Å^−3

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.

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

	x	y	z	Uiso*/Ueq
O1	0.28497 (14)	0.93720 (14)	0.37042 (13)	0.0200 (3)
C2	0.1787 (2)	1.0766 (2)	0.31200 (19)	0.0187 (4)
C3	0.1226 (2)	1.1286 (2)	0.1615 (2)	0.0238 (4)
H3	0.1564	1.0706	0.0865	0.029*
C4	0.0139 (2)	1.2711 (2)	0.1283 (2)	0.0262 (4)
H4	−0.0290	1.3123	0.0275	0.031*
C5	−0.0340 (2)	1.3557 (2)	0.2396 (2)	0.0263 (4)
H5	−0.1087	1.4529	0.2124	0.032*
C6	0.0244 (2)	1.3019 (2)	0.3881 (2)	0.0241 (4)
H6	−0.0088	1.3605	0.4626	0.029*
C7	0.1341 (2)	1.1583 (2)	0.42515 (19)	0.0199 (4)
C8	0.21973 (19)	1.0612 (2)	0.56235 (19)	0.0196 (4)
C9	0.2088 (2)	1.1041 (2)	0.7129 (2)	0.0240 (4)
O10	0.12543 (16)	1.22824 (17)	0.72588 (16)	0.0316 (3)
O11	0.29268 (17)	1.00405 (17)	0.82984 (14)	0.0292 (3)
H11	0.351 (3)	0.912 (3)	0.799 (2)	0.035*
C12	0.3067 (2)	0.9306 (2)	0.52302 (19)	0.0194 (4)
C13	0.4126 (2)	0.7817 (2)	0.6104 (2)	0.0208 (4)
O14	0.43702 (15)	0.76548 (15)	0.75211 (14)	0.0267 (3)
O15	0.46973 (15)	0.68096 (15)	0.53758 (14)	0.0254 (3)
N16	0.42923 (18)	0.6289 (2)	0.25612 (18)	0.0231 (3)
H16A	0.422 (2)	0.685 (3)	0.320 (2)	0.028*
H16B	0.461 (2)	0.517 (3)	0.320 (2)	0.028*
C17	0.2688 (2)	0.6422 (3)	0.2019 (3)	0.0346 (5)
H17A	0.2760	0.5708	0.1365	0.052*
H17B	0.2398	0.7579	0.1350	0.052*
H17C	0.1842	0.6068	0.2982	0.052*
C18	0.5617 (2)	0.6885 (3)	0.1173 (2)	0.0311 (4)
H18A	0.5317	0.8044	0.0516	0.047*
H18B	0.5775	0.6194	0.0485	0.047*
H18C	0.6639	0.6815	0.1596	0.047*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0236 (6)	0.0206 (6)	0.0170 (6)	−0.0010 (5)	−0.0043 (5)	−0.0077 (5)
C2	0.0181 (8)	0.0175 (8)	0.0198 (8)	−0.0035 (7)	−0.0025 (6)	−0.0050 (6)
C3	0.0241 (9)	0.0273 (9)	0.0185 (8)	−0.0084 (8)	−0.0010 (7)	−0.0048 (7)
C4	0.0252 (9)	0.0282 (9)	0.0207 (8)	−0.0077 (8)	−0.0052 (7)	−0.0002 (7)
C5	0.0201 (9)	0.0215 (9)	0.0313 (10)	−0.0018 (7)	−0.0042 (7)	−0.0021 (7)
C6	0.0217 (9)	0.0224 (9)	0.0268 (9)	−0.0029 (7)	−0.0009 (7)	−0.0080 (7)
C7	0.0182 (8)	0.0201 (9)	0.0208 (8)	−0.0063 (7)	−0.0009 (7)	−0.0056 (7)
C8	0.0181 (8)	0.0213 (9)	0.0198 (8)	−0.0056 (7)	−0.0018 (6)	−0.0066 (7)
C9	0.0224 (9)	0.0276 (10)	0.0254 (9)	−0.0051 (8)	−0.0016 (7)	−0.0131 (7)
O10	0.0302 (7)	0.0361 (8)	0.0362 (7)	0.0035 (6)	−0.0072 (6)	−0.0230 (6)
O11	0.0360 (8)	0.0341 (8)	0.0224 (6)	0.0027 (6)	−0.0092 (5)	−0.0155 (6)
C12	0.0225 (9)	0.0224 (9)	0.0153 (8)	−0.0063 (7)	−0.0018 (6)	−0.0078 (6)
C13	0.0223 (9)	0.0211 (9)	0.0204 (8)	−0.0052 (7)	−0.0035 (7)	−0.0071 (7)
O14	0.0316 (7)	0.0287 (7)	0.0216 (6)	0.0015 (6)	−0.0089 (5)	−0.0102 (5)
O15	0.0309 (7)	0.0221 (7)	0.0247 (6)	0.0032 (5)	−0.0070 (5)	−0.0107 (5)
N16	0.0276 (8)	0.0221 (8)	0.0221 (7)	−0.0008 (6)	−0.0053 (6)	−0.0105 (6)
C17	0.0238 (10)	0.0394 (11)	0.0453 (12)	−0.0048 (9)	−0.0062 (8)	−0.0188 (9)
C18	0.0268 (10)	0.0380 (11)	0.0303 (10)	−0.0084 (8)	−0.0028 (8)	−0.0123 (8)

Geometric parameters (Å, º)

O1—C12	1.3768 (19)	C9—O11	1.322 (2)
O1—C2	1.379 (2)	O11—H11	0.97 (2)
C2—C3	1.390 (2)	C12—C13	1.491 (2)
C2—C7	1.392 (2)	C13—O15	1.254 (2)
C3—C4	1.387 (3)	C13—O14	1.263 (2)
C3—H3	0.9500	N16—C18	1.478 (2)
C4—C5	1.399 (3)	N16—C17	1.481 (2)
C4—H4	0.9500	N16—H16A	0.87 (2)
C5—C6	1.381 (3)	N16—H16B	0.96 (2)
C5—H5	0.9500	C17—H17A	0.9800
C6—C7	1.400 (2)	C17—H17B	0.9800
C6—H6	0.9500	C17—H17C	0.9800
C7—C8	1.447 (2)	C18—H18A	0.9800
C8—C12	1.366 (2)	C18—H18B	0.9800
C8—C9	1.493 (2)	C18—H18C	0.9800
C9—O10	1.218 (2)
C12—O1—C2	106.06 (12)	C9—O11—H11	110.0 (12)
O1—C2—C3	124.94 (15)	C8—C12—O1	111.52 (14)
O1—C2—C7	110.65 (14)	C8—C12—C13	134.43 (15)
C3—C2—C7	124.40 (17)	O1—C12—C13	114.00 (14)
C4—C3—C2	115.40 (17)	O15—C13—O14	124.86 (16)
C4—C3—H3	122.3	O15—C13—C12	117.21 (15)
C2—C3—H3	122.3	O14—C13—C12	117.92 (15)
C3—C4—C5	121.63 (17)	C18—N16—C17	112.67 (14)
C3—C4—H4	119.2	C18—N16—H16A	108.8 (13)
C5—C4—H4	119.2	C17—N16—H16A	110.0 (13)
C6—C5—C4	121.80 (17)	C18—N16—H16B	108.4 (11)
C6—C5—H5	119.1	C17—N16—H16B	111.2 (12)
C4—C5—H5	119.1	H16A—N16—H16B	105.5 (18)
C5—C6—C7	117.89 (17)	N16—C17—H17A	109.5
C5—C6—H6	121.1	N16—C17—H17B	109.5
C7—C6—H6	121.1	H17A—C17—H17B	109.5
C2—C7—C6	118.87 (16)	N16—C17—H17C	109.5
C2—C7—C8	105.50 (15)	H17A—C17—H17C	109.5
C6—C7—C8	135.62 (17)	H17B—C17—H17C	109.5
C12—C8—C7	106.26 (14)	N16—C18—H18A	109.5
C12—C8—C9	129.68 (16)	N16—C18—H18B	109.5
C7—C8—C9	124.06 (16)	H18A—C18—H18B	109.5
O10—C9—O11	121.56 (16)	N16—C18—H18C	109.5
O10—C9—C8	120.51 (16)	H18A—C18—H18C	109.5
O11—C9—C8	117.93 (16)	H18B—C18—H18C	109.5

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O11—H11···O14	0.97 (2)	1.51 (2)	2.4817 (19)	178 (2)
N16—H16A···O15	0.87 (2)	2.02 (2)	2.7798 (19)	145.2 (18)
N16—H16A···O1	0.87 (2)	2.45 (2)	3.185 (2)	142.9 (17)
N16—H16B···O15^i	0.96 (2)	1.80 (2)	2.750 (2)	171.0 (18)

Symmetry code: (i) −x+1, −y+1, −z+1.

(II) Bis(3-carboxy-1-benzofuran-2-carboxylato-κO³)tetrakis(1H-imidazole- κN³)copper(II)

Crystal data

[Cu(C10H5O5)2(C3H4N2)4]	Z = 1
Mr = 746.15	F(000) = 383
Triclinic, P1	Dx = 1.555 Mg m^−3
a = 8.1383 (2) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.9782 (3) Å	Cell parameters from 2893 reflections
c = 11.3225 (2) Å	θ = 3.0–27.9°
α = 107.5049 (12)°	µ = 0.76 mm^−1
β = 108.4826 (14)°	T = 110 K
γ = 99.4472 (9)°	Rod, blue
V = 796.68 (4) Å^3	0.45 × 0.30 × 0.25 mm

Data collection

Nonius KappaCCD area-detector diffractometer	3753 independent reflections
Radiation source: fine-focus sealed tube	3386 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.023
Detector resolution: 12.8 pixels mm^-1	θmax = 27.9°, θmin = 3.0°
1 deg. ϕ and ω scans	h = 0→10
Absorption correction: multi-scan (Blessing, 1995)	k = −13→12
Tmin = 0.726, Tmax = 0.833	l = −14→13
8773 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.097	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.047P)^2 + 0.6699P] where P = (Fo^2 + 2Fc^2)/3
3753 reflections	(Δ/σ)max < 0.001
232 parameters	Δρmax = 0.39 e Å^−3
0 restraints	Δρmin = −0.62 e Å^−3

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.

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

	x	y	z	Uiso*/Ueq
Cu1	0.0000	0.0000	0.0000	0.01492 (10)
N2	−0.1003 (2)	0.14435 (16)	0.10111 (14)	0.0161 (3)
C3	−0.0127 (2)	0.26220 (19)	0.21309 (17)	0.0176 (3)
H3	0.1132	0.2892	0.2654	0.021*
N4	−0.1246 (2)	0.33810 (17)	0.24289 (15)	0.0190 (3)
H4	−0.0950	0.4194	0.3131	0.023*
C5	−0.2946 (3)	0.2662 (2)	0.14391 (18)	0.0208 (4)
H5	−0.4019	0.2948	0.1376	0.025*
C6	−0.2783 (2)	0.1463 (2)	0.05704 (18)	0.0194 (4)
H6	−0.3742	0.0751	−0.0215	0.023*
N7	0.1092 (2)	0.15281 (16)	−0.05753 (14)	0.0163 (3)
C8	0.2159 (3)	0.2953 (2)	0.01880 (18)	0.0213 (4)
H8	0.2724	0.3365	0.1142	0.026*
C9	0.2272 (3)	0.3676 (2)	−0.06459 (19)	0.0257 (4)
H9	0.2913	0.4670	−0.0390	0.031*
N10	0.1270 (2)	0.26745 (18)	−0.19280 (16)	0.0219 (3)
H10	0.1103	0.2836	−0.2674	0.026*
C11	0.0593 (3)	0.1408 (2)	−0.18408 (18)	0.0200 (4)
H11	−0.0150	0.0535	−0.2592	0.024*
O12	0.27000 (17)	0.07457 (14)	0.20648 (12)	0.0204 (3)
C13	0.4126 (2)	0.16088 (19)	0.29453 (16)	0.0155 (3)
O14	0.44501 (17)	0.30256 (14)	0.32920 (12)	0.0181 (3)
H14	0.5612	0.3544	0.3987	0.022*
C15	0.5536 (2)	0.10199 (18)	0.36470 (16)	0.0140 (3)
C16	0.5292 (2)	−0.05151 (18)	0.34538 (16)	0.0151 (3)
C17	0.3887 (2)	−0.1824 (2)	0.26711 (17)	0.0187 (3)
H17	0.2769	−0.1834	0.2058	0.022*
C18	0.4188 (3)	−0.3100 (2)	0.28246 (19)	0.0223 (4)
H18	0.3250	−0.3996	0.2311	0.027*
C19	0.5835 (3)	−0.3109 (2)	0.37144 (19)	0.0217 (4)
H19	0.5987	−0.4008	0.3789	0.026*
C20	0.7249 (3)	−0.1830 (2)	0.44888 (18)	0.0187 (3)
H20	0.8373	−0.1822	0.5094	0.022*
C21	0.6917 (2)	−0.05642 (18)	0.43239 (16)	0.0152 (3)
O22	0.81303 (16)	0.08149 (13)	0.50042 (12)	0.0156 (2)
C23	0.7251 (2)	0.17508 (18)	0.45845 (16)	0.0142 (3)
C24	0.8332 (2)	0.33294 (19)	0.52317 (16)	0.0148 (3)
O25	0.99497 (17)	0.36447 (14)	0.59757 (12)	0.0177 (3)
O26	0.75168 (17)	0.42565 (13)	0.49777 (13)	0.0185 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.01893 (16)	0.01223 (16)	0.01287 (15)	0.00474 (11)	0.00538 (11)	0.00448 (11)
N2	0.0193 (7)	0.0133 (7)	0.0149 (7)	0.0047 (6)	0.0059 (6)	0.0050 (5)
C3	0.0198 (8)	0.0149 (8)	0.0157 (8)	0.0046 (7)	0.0060 (6)	0.0039 (6)
N4	0.0235 (8)	0.0154 (7)	0.0181 (7)	0.0062 (6)	0.0096 (6)	0.0044 (6)
C5	0.0194 (9)	0.0228 (9)	0.0210 (9)	0.0076 (7)	0.0088 (7)	0.0076 (7)
C6	0.0167 (8)	0.0205 (9)	0.0181 (8)	0.0035 (7)	0.0053 (7)	0.0058 (7)
N7	0.0186 (7)	0.0145 (7)	0.0144 (7)	0.0051 (6)	0.0049 (5)	0.0052 (5)
C8	0.0259 (9)	0.0180 (9)	0.0155 (8)	0.0021 (7)	0.0046 (7)	0.0062 (7)
C9	0.0310 (10)	0.0197 (9)	0.0228 (9)	0.0013 (8)	0.0074 (8)	0.0095 (7)
N10	0.0257 (8)	0.0242 (8)	0.0177 (7)	0.0056 (7)	0.0079 (6)	0.0119 (6)
C11	0.0223 (9)	0.0210 (9)	0.0160 (8)	0.0051 (7)	0.0069 (7)	0.0076 (7)
O12	0.0190 (6)	0.0200 (6)	0.0157 (6)	0.0049 (5)	−0.0004 (5)	0.0060 (5)
C13	0.0189 (8)	0.0180 (8)	0.0113 (7)	0.0072 (7)	0.0057 (6)	0.0067 (6)
O14	0.0198 (6)	0.0151 (6)	0.0174 (6)	0.0064 (5)	0.0031 (5)	0.0071 (5)
C15	0.0175 (8)	0.0138 (8)	0.0104 (7)	0.0053 (6)	0.0047 (6)	0.0049 (6)
C16	0.0191 (8)	0.0137 (8)	0.0129 (7)	0.0054 (6)	0.0069 (6)	0.0048 (6)
C17	0.0212 (8)	0.0164 (8)	0.0161 (8)	0.0042 (7)	0.0065 (7)	0.0046 (6)
C18	0.0294 (10)	0.0138 (8)	0.0211 (9)	0.0024 (7)	0.0111 (7)	0.0039 (7)
C19	0.0328 (10)	0.0137 (8)	0.0256 (9)	0.0108 (7)	0.0165 (8)	0.0091 (7)
C20	0.0245 (9)	0.0187 (8)	0.0195 (8)	0.0115 (7)	0.0118 (7)	0.0097 (7)
C21	0.0189 (8)	0.0132 (8)	0.0144 (8)	0.0050 (6)	0.0074 (6)	0.0049 (6)
O22	0.0169 (6)	0.0129 (6)	0.0163 (6)	0.0054 (5)	0.0036 (5)	0.0067 (5)
C23	0.0179 (8)	0.0144 (8)	0.0139 (7)	0.0081 (7)	0.0067 (6)	0.0079 (6)
C24	0.0180 (8)	0.0144 (8)	0.0117 (7)	0.0042 (6)	0.0061 (6)	0.0046 (6)
O25	0.0168 (6)	0.0162 (6)	0.0165 (6)	0.0031 (5)	0.0036 (5)	0.0054 (5)
O26	0.0207 (6)	0.0133 (6)	0.0204 (6)	0.0060 (5)	0.0050 (5)	0.0072 (5)

Geometric parameters (Å, º)

Cu1—N2^i	2.0095 (14)	O12—C13	1.226 (2)
Cu1—N2	2.0095 (14)	C13—O14	1.304 (2)
Cu1—N7	2.0146 (15)	C13—C15	1.489 (2)
Cu1—N7^i	2.0146 (15)	O14—H14	0.9508
N2—C3	1.324 (2)	C15—C23	1.367 (2)
N2—C6	1.380 (2)	C15—C16	1.451 (2)
C3—N4	1.336 (2)	C16—C21	1.395 (2)
C3—H3	0.9500	C16—C17	1.403 (2)
N4—C5	1.375 (2)	C17—C18	1.386 (3)
N4—H4	0.8800	C17—H17	0.9500
C5—C6	1.358 (3)	C18—C19	1.402 (3)
C5—H5	0.9500	C18—H18	0.9500
C6—H6	0.9500	C19—C20	1.388 (3)
N7—C11	1.321 (2)	C19—H19	0.9500
N7—C8	1.379 (2)	C20—C21	1.388 (2)
C8—C9	1.365 (3)	C20—H20	0.9500
C8—H8	0.9500	C21—O22	1.377 (2)
C9—N10	1.371 (2)	O22—C23	1.371 (2)
C9—H9	0.9500	C23—C24	1.495 (2)
N10—C11	1.339 (2)	C24—O25	1.243 (2)
N10—H10	0.8800	C24—O26	1.272 (2)
C11—H11	0.9500
N2^i—Cu1—N2	180.00 (6)	N7—C11—H11	124.4
N2^i—Cu1—N7	89.79 (6)	N10—C11—H11	124.4
N2—Cu1—N7	90.21 (6)	O12—C13—O14	122.31 (16)
N2^i—Cu1—N7^i	90.21 (6)	O12—C13—C15	118.91 (16)
N2—Cu1—N7^i	89.79 (6)	O14—C13—C15	118.78 (15)
N7—Cu1—N7^i	180.0	C13—O14—H14	112.2
C3—N2—C6	105.90 (15)	C23—C15—C16	106.14 (14)
C3—N2—Cu1	128.81 (13)	C23—C15—C13	129.32 (16)
C6—N2—Cu1	125.00 (12)	C16—C15—C13	124.54 (15)
N2—C3—N4	111.14 (16)	C21—C16—C17	118.86 (16)
N2—C3—H3	124.4	C21—C16—C15	105.25 (15)
N4—C3—H3	124.4	C17—C16—C15	135.88 (16)
C3—N4—C5	107.61 (15)	C18—C17—C16	117.65 (17)
C3—N4—H4	126.2	C18—C17—H17	121.2
C5—N4—H4	126.2	C16—C17—H17	121.2
C6—C5—N4	106.21 (16)	C17—C18—C19	121.99 (17)
C6—C5—H5	126.9	C17—C18—H18	119.0
N4—C5—H5	126.9	C19—C18—H18	119.0
C5—C6—N2	109.13 (16)	C20—C19—C18	121.32 (17)
C5—C6—H6	125.4	C20—C19—H19	119.3
N2—C6—H6	125.4	C18—C19—H19	119.3
C11—N7—C8	105.94 (15)	C21—C20—C19	115.76 (17)
C11—N7—Cu1	123.34 (12)	C21—C20—H20	122.1
C8—N7—Cu1	129.56 (12)	C19—C20—H20	122.1
C9—C8—N7	109.11 (16)	O22—C21—C20	124.88 (16)
C9—C8—H8	125.4	O22—C21—C16	110.70 (14)
N7—C8—H8	125.4	C20—C21—C16	124.42 (16)
C8—C9—N10	106.00 (17)	C23—O22—C21	106.19 (13)
C8—C9—H9	127.0	C15—C23—O22	111.71 (15)
N10—C9—H9	127.0	C15—C23—C24	133.42 (15)
C11—N10—C9	107.73 (15)	O22—C23—C24	114.87 (14)
C11—N10—H10	126.1	O25—C24—O26	124.71 (16)
C9—N10—H10	126.1	O25—C24—C23	118.13 (15)
N7—C11—N10	111.22 (16)	O26—C24—C23	117.16 (15)

Symmetry code: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O14—H14···O26	0.95	1.49	2.4380 (17)	174
N4—H4···O25^ii	0.88	1.98	2.779 (2)	150
N10—H10···O25^iii	0.88	1.99	2.799 (2)	153

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

(III) heptaaquabis(3-carboxy-1-benzofuran-2-carboxylato-κO³)lanthanum(IV) bis(hemihydrogen 3-carboxy-1-benzofuran-2-carboxylate) tetrahydrate

Crystal data

[La(C10H5O5)2(H2O)7](C10H5.5O5)2·4H2O	Dx = 1.610 Mg m^−3
Mr = 1156.64	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Fdd2	Cell parameters from 2586 reflections
a = 38.9250 (16) Å	θ = 1.4–26.0°
b = 8.6186 (3) Å	µ = 1.00 mm^−1
c = 28.4430 (9) Å	T = 110 K
V = 9542.0 (6) Å^3	Prism, colorless
Z = 8	0.30 × 0.25 × 0.15 mm
F(000) = 4688

Data collection

Nonius KappaCCD diffractometer	4497 independent reflections
Radiation source: fine-focus sealed tube	3667 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.083
Detector resolution: 12.8 pixels mm^-1	θmax = 26.0°, θmin = 2.5°
0.6° ϕ scans	h = −47→48
Absorption correction: multi-scan (Blessing, 1995)	k = −10→10
Tmin = 0.755, Tmax = 0.866	l = −34→34
16083 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.049	H-atom parameters constrained
wR(F^2) = 0.114	w = 1/[σ^2(Fo^2) + (0.0682P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.00	(Δ/σ)max = 0.001
4497 reflections	Δρmax = 0.64 e Å^−3
309 parameters	Δρmin = −0.79 e Å^−3
1 restraint	Absolute structure: Flack (1983), 2093 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.49 (2)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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.

The structure represents a racemic twin. It contains solvent trapped between the molecular entities, which could not be reliably identified (though it is most probably disordered water). Conventional refinement with the solvent excluded converged to R1=0.071, the difference-Fourier electron density map four significant peaks within 1.9-2.6 e/ų Its contribution was then subtracted from the diffraction data, using the Squeeze procedure in the Platon software (Spek, 2003). It showed that there are 8 voids per cell of 200 ų each. The residual electron count was assessed to be 304 e/cell, which corresponds nicely with 4 water molecules per void. The H-atom (50% occupancy) bound to either O27 or O28 of the non-coordinated ligand could not be located in difference-Fourier maps.

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

	x	y	z	Uiso*/Ueq
La1	0.2500	0.2500	0.016942 (15)	0.03005 (13)
O2	0.2500	0.2500	−0.0736 (2)	0.0434 (15)
H2	0.2657	0.2844	−0.0943	0.065*
O3	0.29876 (10)	0.0692 (5)	−0.01296 (15)	0.0366 (10)
H3A	0.3095	0.0723	−0.0410	0.055*
H3B	0.3141	0.0099	0.0025	0.055*
O4	0.20094 (10)	0.0768 (5)	−0.01279 (15)	0.0350 (10)
H4A	0.1889	0.0525	−0.0388	0.053*
H4B	0.1832	0.0850	0.0073	0.053*
O5	0.25171 (10)	0.5144 (4)	0.05874 (15)	0.0326 (10)
H5A	0.2390	0.6009	0.0623	0.049*
H5B	0.2724	0.5557	0.0651	0.049*
O6	0.29545 (10)	0.2388 (4)	0.07933 (14)	0.0313 (9)
O7	0.34427 (11)	0.3558 (5)	0.06065 (15)	0.0372 (10)
H7	0.3647	0.3896	0.0712	0.056*
C8	0.32578 (15)	0.2674 (7)	0.0873 (2)	0.0314 (13)
C9	0.34196 (15)	0.1973 (7)	0.1295 (2)	0.0288 (13)
C10	0.37537 (15)	0.2118 (7)	0.1450 (2)	0.0330 (14)
C11	0.40573 (17)	0.2986 (8)	0.1282 (2)	0.0369 (15)
O12	0.40245 (11)	0.3845 (5)	0.09123 (16)	0.0407 (11)
O13	0.43360 (11)	0.2853 (6)	0.14948 (17)	0.0459 (12)
O14	0.38116 (10)	0.1265 (5)	0.18467 (15)	0.0355 (10)
C15	0.35020 (15)	0.0536 (7)	0.1949 (2)	0.0299 (13)
C16	0.34549 (16)	−0.0461 (7)	0.2324 (2)	0.0350 (14)
H16	0.3633	−0.0691	0.2542	0.042*
C17	0.31311 (16)	−0.1097 (7)	0.2358 (2)	0.0386 (15)
H17	0.3083	−0.1803	0.2606	0.046*
C18	0.28690 (16)	−0.0726 (7)	0.2035 (2)	0.0363 (14)
H18	0.2649	−0.1182	0.2071	0.044*
C19	0.29252 (15)	0.0287 (7)	0.1665 (2)	0.0322 (14)
H19	0.2747	0.0533	0.1449	0.039*
C20	0.32499 (16)	0.0931 (6)	0.1620 (2)	0.0295 (13)
O21	0.30012 (13)	−0.2323 (5)	0.0713 (2)	0.0512 (13)
O22	0.34463 (12)	−0.0825 (5)	0.05468 (16)	0.0424 (11)
H22	0.3651	−0.0477	0.0651	0.064*
C23	0.3300 (2)	−0.1885 (8)	0.0793 (3)	0.0447 (17)
C24	0.3504 (2)	−0.2624 (7)	0.1192 (2)	0.0435 (16)
C25	0.38462 (19)	−0.2280 (7)	0.1322 (2)	0.0389 (16)
C26	0.41031 (19)	−0.1225 (8)	0.1172 (3)	0.0469 (18)
O27	0.40403 (13)	−0.0435 (6)	0.08024 (17)	0.0510 (13)
O28	0.43768 (12)	−0.1107 (6)	0.14133 (19)	0.0526 (12)
O29	0.39356 (12)	−0.3174 (6)	0.17143 (17)	0.0464 (11)
C30	0.36430 (17)	−0.4032 (7)	0.1816 (3)	0.0418 (16)
C31	0.3638 (2)	−0.5066 (8)	0.2215 (3)	0.0508 (18)
H31	0.3833	−0.5233	0.2410	0.061*
C32	0.33165 (18)	−0.5818 (8)	0.2291 (3)	0.0433 (16)
H32	0.3288	−0.6522	0.2545	0.052*
C33	0.30426 (18)	−0.5503 (7)	0.1986 (2)	0.0412 (16)
H33	0.2828	−0.5996	0.2042	0.049*
C34	0.3071 (2)	−0.4491 (9)	0.1601 (3)	0.0530 (19)
H34	0.2881	−0.4312	0.1397	0.064*
C35	0.33778 (19)	−0.3776 (8)	0.1530 (3)	0.0459 (18)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
La1	0.0226 (2)	0.0371 (2)	0.0305 (2)	0.0015 (3)	0.000	0.000
O2	0.036 (4)	0.066 (4)	0.028 (3)	0.006 (3)	0.000	0.000
O3	0.026 (2)	0.043 (2)	0.040 (3)	0.013 (2)	0.0039 (19)	0.003 (2)
O4	0.019 (2)	0.050 (2)	0.036 (2)	0.0007 (19)	−0.0041 (17)	−0.0113 (19)
O5	0.025 (2)	0.035 (2)	0.038 (2)	−0.0012 (18)	0.0024 (17)	−0.0049 (16)
O6	0.020 (2)	0.040 (2)	0.034 (2)	0.0003 (18)	−0.0046 (17)	−0.0004 (18)
O7	0.030 (2)	0.044 (2)	0.038 (2)	−0.003 (2)	−0.0028 (19)	0.0104 (19)
C8	0.024 (3)	0.039 (3)	0.032 (3)	0.008 (3)	−0.007 (2)	−0.002 (3)
C9	0.024 (3)	0.038 (3)	0.025 (3)	0.002 (2)	0.002 (2)	0.002 (2)
C10	0.026 (3)	0.044 (4)	0.029 (3)	0.002 (2)	−0.006 (3)	−0.002 (2)
C11	0.029 (3)	0.046 (4)	0.036 (4)	0.002 (3)	−0.006 (3)	0.004 (3)
O12	0.034 (3)	0.050 (3)	0.038 (3)	−0.006 (2)	−0.0026 (19)	0.008 (2)
O13	0.026 (2)	0.068 (3)	0.044 (3)	−0.007 (2)	−0.006 (2)	0.015 (2)
O14	0.024 (2)	0.041 (2)	0.041 (3)	−0.0037 (18)	−0.0048 (18)	0.0064 (19)
C15	0.022 (3)	0.032 (3)	0.035 (4)	−0.001 (2)	−0.004 (3)	−0.007 (3)
C16	0.029 (3)	0.043 (3)	0.033 (3)	−0.002 (3)	−0.007 (3)	0.005 (3)
C17	0.036 (4)	0.033 (3)	0.046 (4)	−0.004 (3)	0.004 (3)	0.000 (3)
C18	0.030 (3)	0.036 (3)	0.043 (4)	−0.003 (3)	0.000 (3)	0.001 (3)
C19	0.023 (3)	0.036 (3)	0.038 (3)	−0.002 (2)	−0.004 (3)	0.001 (3)
C20	0.031 (3)	0.020 (3)	0.037 (3)	−0.001 (3)	0.001 (3)	−0.003 (2)
O21	0.037 (3)	0.042 (3)	0.075 (4)	0.004 (2)	0.001 (2)	−0.005 (2)
O22	0.041 (3)	0.044 (3)	0.042 (3)	0.006 (2)	−0.002 (2)	−0.001 (2)
C23	0.050 (5)	0.032 (3)	0.052 (4)	−0.001 (3)	0.014 (4)	−0.010 (3)
C24	0.054 (4)	0.038 (3)	0.038 (4)	0.007 (3)	0.010 (3)	−0.006 (3)
C25	0.054 (4)	0.035 (4)	0.029 (3)	0.018 (3)	−0.014 (3)	−0.006 (3)
C26	0.042 (4)	0.041 (4)	0.058 (5)	0.002 (3)	0.003 (4)	−0.012 (4)
O27	0.048 (3)	0.067 (3)	0.038 (3)	0.004 (2)	−0.006 (2)	0.002 (2)
O28	0.044 (3)	0.055 (3)	0.058 (3)	0.003 (2)	−0.006 (3)	−0.008 (2)
O29	0.042 (3)	0.052 (3)	0.045 (3)	−0.002 (2)	−0.004 (2)	0.007 (2)
C30	0.033 (4)	0.034 (4)	0.059 (5)	−0.007 (3)	−0.003 (3)	−0.003 (3)
C31	0.049 (4)	0.051 (4)	0.052 (4)	0.004 (4)	−0.013 (4)	−0.018 (4)
C32	0.045 (4)	0.039 (4)	0.046 (4)	−0.004 (3)	0.004 (3)	−0.008 (3)
C33	0.044 (4)	0.039 (3)	0.041 (4)	−0.001 (3)	0.004 (3)	−0.003 (3)
C34	0.053 (5)	0.051 (4)	0.054 (5)	0.002 (4)	0.002 (4)	−0.017 (3)
C35	0.048 (4)	0.045 (4)	0.045 (4)	0.002 (3)	0.004 (3)	−0.013 (3)

Geometric parameters (Å, º)

La1—O6^i	2.508 (4)	C16—C17	1.378 (9)
La1—O6	2.508 (4)	C16—H16	0.9500
La1—O4	2.567 (4)	C17—C18	1.411 (9)
La1—O4^i	2.567 (4)	C17—H17	0.9500
La1—O5	2.571 (4)	C18—C19	1.384 (9)
La1—O5^i	2.571 (4)	C18—H18	0.9500
La1—O2	2.574 (6)	C19—C20	1.386 (8)
La1—O3	2.599 (4)	C19—H19	0.9500
La1—O3^i	2.599 (4)	O21—C23	1.243 (9)
O2—H2	0.8997	O22—C23	1.285 (8)
O3—H3A	0.9002	O22—H22	0.9002
O3—H3B	0.9000	C23—C24	1.524 (11)
O4—H4A	0.8999	C24—C25	1.415 (10)
O4—H4B	0.8999	C24—C35	1.466 (10)
O5—H5A	0.9002	C25—O29	1.401 (8)
O5—H5B	0.8999	C25—C26	1.417 (10)
O6—C8	1.227 (7)	C26—O28	1.272 (9)
O7—C8	1.294 (7)	C26—O27	1.275 (9)
O7—H7	0.9000	O29—C30	1.388 (8)
C8—C9	1.483 (8)	C30—C35	1.333 (10)
C9—C10	1.379 (8)	C30—C31	1.444 (11)
C9—C20	1.448 (8)	C31—C32	1.427 (10)
C10—O14	1.366 (7)	C31—H31	0.9500
C10—C11	1.478 (9)	C32—C33	1.401 (10)
C11—O13	1.247 (7)	C32—H32	0.9500
C11—O12	1.293 (8)	C33—C34	1.403 (11)
O14—C15	1.389 (7)	C33—H33	0.9500
C15—C16	1.383 (9)	C34—C35	1.361 (10)
C15—C20	1.398 (8)	C34—H34	0.9500
O6^i—La1—O6	89.91 (19)	C9—C10—C11	134.2 (6)
O6^i—La1—O4	74.37 (13)	O13—C11—O12	122.2 (6)
O6—La1—O4	137.37 (13)	O13—C11—C10	119.5 (6)
O6^i—La1—O4^i	137.37 (13)	O12—C11—C10	118.2 (5)
O6—La1—O4^i	74.37 (13)	C10—O14—C15	105.8 (4)
O4—La1—O4^i	141.53 (19)	C16—C15—O14	123.9 (5)
O6^i—La1—O5	69.94 (12)	C16—C15—C20	125.1 (5)
O6—La1—O5	71.85 (13)	O14—C15—C20	111.0 (5)
O4—La1—O5	133.38 (12)	C15—C16—C17	115.0 (6)
O4^i—La1—O5	67.53 (13)	C15—C16—H16	122.5
O6^i—La1—O5^i	71.85 (13)	C17—C16—H16	122.5
O6—La1—O5^i	69.94 (12)	C16—C17—C18	121.7 (6)
O4—La1—O5^i	67.54 (13)	C16—C17—H17	119.2
O4^i—La1—O5^i	133.38 (12)	C18—C17—H17	119.2
O5—La1—O5^i	124.91 (19)	C19—C18—C17	121.6 (6)
O6^i—La1—O2	135.05 (9)	C19—C18—H18	119.2
O6—La1—O2	135.04 (9)	C17—C18—H18	119.2
O4—La1—O2	70.76 (10)	C20—C19—C18	117.8 (6)
O4^i—La1—O2	70.77 (10)	C20—C19—H19	121.1
O5—La1—O2	117.54 (10)	C18—C19—H19	121.1
O5^i—La1—O2	117.55 (10)	C19—C20—C15	118.7 (5)
O6^i—La1—O3	140.34 (13)	C19—C20—C9	136.3 (6)
O6—La1—O3	72.14 (13)	C15—C20—C9	105.0 (5)
O4—La1—O3	94.98 (13)	C23—O22—H22	116.7
O4^i—La1—O3	72.39 (14)	O21—C23—O22	122.1 (7)
O5—La1—O3	131.60 (13)	O21—C23—C24	119.8 (6)
O5^i—La1—O3	68.82 (13)	O22—C23—C24	118.1 (7)
O2—La1—O3	70.90 (10)	C25—C24—C35	106.6 (6)
O6^i—La1—O3^i	72.14 (13)	C25—C24—C23	126.7 (6)
O6—La1—O3^i	140.34 (13)	C35—C24—C23	126.6 (7)
O4—La1—O3^i	72.39 (14)	C24—C25—O29	109.1 (6)
O4^i—La1—O3^i	94.99 (13)	C24—C25—C26	136.1 (6)
O5—La1—O3^i	68.83 (13)	O29—C25—C26	114.7 (6)
O5^i—La1—O3^i	131.60 (13)	O28—C26—O27	124.2 (7)
O2—La1—O3^i	70.90 (10)	O28—C26—C25	118.7 (7)
O3—La1—O3^i	141.80 (19)	O27—C26—C25	117.1 (7)
La1—O2—H2	130.9	C30—O29—C25	104.8 (5)
La1—O3—H3A	127.7	C35—C30—O29	114.9 (6)
La1—O3—H3B	131.6	C35—C30—C31	124.9 (7)
H3A—O3—H3B	98.1	O29—C30—C31	120.2 (6)
La1—O4—H4A	142.4	C30—C31—C32	114.2 (6)
La1—O4—H4B	108.5	C30—C31—H31	122.9
H4A—O4—H4B	98.2	C32—C31—H31	122.9
La1—O5—H5A	140.5	C33—C32—C31	119.1 (7)
La1—O5—H5B	117.9	C33—C32—H32	120.4
H5A—O5—H5B	98.1	C31—C32—H32	120.4
C8—O6—La1	143.4 (4)	C32—C33—C34	123.0 (7)
C8—O7—H7	119.1	C32—C33—H33	118.5
O6—C8—O7	123.0 (5)	C34—C33—H33	118.5
O6—C8—C9	118.5 (6)	C35—C34—C33	117.8 (8)
O7—C8—C9	118.5 (5)	C35—C34—H34	121.1
C10—C9—C20	106.4 (5)	C33—C34—H34	121.1
C10—C9—C8	128.5 (6)	C30—C35—C34	121.0 (7)
C20—C9—C8	125.1 (5)	C30—C35—C24	104.7 (7)
O14—C10—C9	111.8 (5)	C34—C35—C24	134.3 (8)
O14—C10—C11	114.0 (5)

Symmetry code: (i) −x+1/2, −y+1/2, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O28^ii	0.90	2.24	2.791 (5)	119
O3—H3A···O28^ii	0.90	2.01	2.838 (7)	152
O3—H3B···O22	0.90	2.06	2.932 (6)	162
O4—H4A···O13^iii	0.90	1.92	2.760 (6)	154
O4—H4B···O7^i	0.90	1.92	2.793 (6)	162
O5—H5A···O21^i	0.90	1.91	2.779 (6)	160
O5—H5B···O21^iv	0.90	2.13	2.906 (6)	144
O7—H7···O12	0.90	1.57	2.438 (6)	160
O22—H22···O27	0.90	1.58	2.447 (7)	161

Symmetry codes: (i) −x+1/2, −y+1/2, z; (ii) −x+3/4, y+1/4, z−1/4; (iii) x−1/4, −y+1/4, z−1/4; (iv) x, y+1, z.