Poly[[tetra-μ₃-acetato-hexa-μ₂-acetato-diaqua-μ₂-oxalato-tetra­praseodymium(III)] dihydrate]

The title complex, {[Pr₄(C₂H₃O₂)₁₀(C₂O₄)(H₂O)₂]·2H₂O}_n, was synthesized under hydro­thermal conditions from praseodymium acetate and the ionic liquid 1-butyl-3-methyl­imidazolium chloride via an in situ oxalate-ligand synthesis. The compound is a two-dimensional polymer and in the structure presents tightly bound planes parallel to (100), which are in turn linked into a three-dimensional network by hydrogen bonds involving both coordinated and solvent water mol­ecules. The oxalate anion lies across an inversion centre and acts as a bridge between pairs of Pr atoms within a tetra­nuclear segment of the polymer.

S1. Comment

Lanthanides are characterized by a high affinity for ligands with hard donor atoms such as O and/or N (Brunet et al.,2007). The compounds thus formed may possess unique photophysical and magnetic properties that make them suitable for applications in advanced materials (Steckl & Zavada, 1999; de Sa et al., 2000; Kido & Okamoto, 2002). The construction of extended structures containing praseodymium or other f-elements bridged by carboxylate groups is of interest because of the large variety of architectures that result from the high and variable coordination numbers of the lanthanides, as well as the versatility of carboxylate ligands.

Ionic liquids (ILs) are a group of ionic compounds having a broad temperature range at which they remain liquid combined with very low vapour pressures, and they have been proposed as potential replacements for conventional organic solvents. ILs are generally composed of one organic cation (such as imidazolium, pyridinium or pyrrolidinum) and an anion (such BF₄^-, PF₆^-, Cl^- etc.); they have been shown to act both as solvents and as reactants which may be incorporated into the final reaction product (for instance, behaving as a charge neutralizer; Cocalia et al., 2006). The use of ILs in the in situ synthesis of ligands in coordination compounds has increased in the last few years, along with efforts to elucidate the mechanisms of the reactions involved (Reichert et al., 2006).

Reported herein is the title new polymeric compound, (I), obtained under hydrothermal conditions via praseodymium acetate and the IL 1-butyl-3-methylimidazolium chloride, [bmim][Cl]. Fig. 1 shows a molecular view of (I), where each ligand is identified by a unique trailing number: acetates 1-5; oxalate 6.

The tetranuclear complex lies acoss an inversion centre located at the centre of the bridging oxalate ligand, so that the asymmetric unit is composed of two Pr^III cations, one water ligand, five acetate anions and half of an oxalate unit; a solvent water molecule completes the asymmetric unit. The two Pr^III cations (Pr1 and Pr2) receive bonds from all five acetate anions, while the oxalate anion coordinates only to Pr1 and the water ligand coordinates only to Pr2. As a result, the metal cations present different PrO₉ (Pr1) and PrO₁₀ (Pr2) environments (Table 1), with Pr—O distances in the range 2.417 (3)–2.698 (3) Å for Pr1 and 2.388 (3)–2.786 (3) Å for Pr2, and bond valence sums of 3.33 and 3.22, respectively. The five acetate ligands, in turn, bind in three different bridging ways: as µ₂-κ²O,O' (simple bridge, acetate 2), as µ₂-κ²O:O',O' (simple bridge–simple chelate, acetates 3 and 5) and as µ₃-κ²O,O:O',O') (double bridge–simple chelate, acetates 1 and 4). The oxalate anion, as usual, binds in a µ₂-κ⁴O:O',O'':O'''(simple bridge–double chelate) mode.

This intricate bonding scheme results in a tight two-dimensional mesh of interlinked Pr^III coordination polyhedra, with the metals joined by a variety of `short' (Pr—O—Pr) and `long' (Pr—O—C—O—Pr) bridges to give Pr···.Pr distances of 4.0618 (3) (Pr1···Pr2, three short bridges), 4.2224 (3) (Pr1···Pr2ⁱ, two short bridges), 6.4045 (3) (Pr1···Pr1ⁱⁱ, two long oxalate bridges) and 4.4995 (3) Å (Pr2···Pr2ⁱⁱⁱ, two short bridges) [symmetry codes: (i) -x + 1, y - 1/2, -z + 3/2; (ii) -x + 1, -y + 1, -z + 2; (iii) -x + 1, -y + 2, -z + 2].

Fig. 2(a) shows a view of one such mesh, parallel to (100). It can be seen that the cations, water ligands and acetate anions generate an infinite layer (represented by light lines) with large centrosymmetric `holes' in it, where the oxalate anions (heavy lines) lie, linking symmetry-related Pr1 centres together. These strongly connected planar structures are further stabilized by a strong `intra-planar' hydrogen bond (Table 2, first entry), while being linked to each other via the other three `interplanar' hydrogen bonds (Table 2, entries 2–4). Figs. 2(a) and 2(b) depict these hydrogen bonds in full detail, while Fig. 2(c) sketches the way in which they operate in the interplanar linkage, through a rather simple chain made out of `conjugated' hydrogen-bonded rings (A and B) threading through a line of inversion centres across the planes. The rings, characterized by graph-set descriptors (Bernstein et al., 1995) R⁴₆(12) (ring A) and R²₂(8) (ring B), are formed by just four non-H atoms (O1W, O2W, Pr2 and O25; Fig. 2c).

Fig. 3 shows the IR and Raman spectra of (I), in the range 500–3000 cm^-1, in which the oxalate and acetate bands can be observed. The peaks are assigned according to previously reported data (Frost, 2004; Ito & Bernstein, 1956). The range 1500–1400 cm^-1 in the Raman spectrum shows the bands associated with double bonds, i.e. C═O stretching of both acetate and oxalate. The antisymmetric C═O stretching extends to 1700 cm^-1 in the IR spectrum. The bands between 1100 and 500 cm^-1 correspond to C—C stretching. The acetate can be distinguished from the oxalate group in the range 3100–2900 cm^-1, in which only the CH stretching vibrations of the acetate are seen.

As a final remark, it should be stated that the reaction responsible for the presence of the oxalate bridge in the final product is not yet fully understood. This situation is by no means unique; in situ oxalate-anion formation under hydrothermal conditions has already been reported, and has been related to the rearrangement or cleavage of organic compounds (Knope & Cahill, 2007; Zhang et al., 2006). However, the mechanisms that lead to oxalate-bridge formation remain to be understood.

Related literature

For related literature, see: Bernstein et al. (1995); Brunet et al. (2007); Cocalia et al. (2006); Frost (2004); Ito & Bernstein (1956); Kido & Okamoto (2002); Knope & Cahill (2007); Reichert et al. (2006); Sa et al. (2000); Steckl & Zavada (1999); Zhang et al. (2006).

S2. Experimental

Compound (I) was synthesized from an aqueous solution of praseodymium acetate (41 mg) and sodium acetate (13 mg) in a 1:1.5 ratio, in the presence of the ionic liquid 1-butyl-3-methylimidazolium chloride (3:1 water–IL ratio). Crystals of (I) were grown in a 45 ml Teflon-lined autoclave under hydrothermal conditions over a period of a few days at 400 K and after slow cooling.

S3. Refinement

Water H atoms were refined with restrained distances [O—H = 0.85 (1) Å and H···H = 1.36 (1) Å]. Methyl groups were idealized (C—H = 0.96 Å) and allowed to ride. In all cases, H-atom displacement parameters were taken as U_iso(H) = 1.2 or 1.5U_eq(host).

Computing details

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); 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: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of (I), with displacement ellipsoids drawn at the 50% probability level, showing both Pr coordination polyhedra and the bridging mode of the oxalate ion, halved by the inversion centre. Dashed lines show the way in which water molecules are involved in hydrogen bonding. [Symmetry codes: (i) -x + 1, y - 1/2, -z + 3/2; (ii) -x + 1, -y + 1, -z + 2; (iii) -x + 1, -y + 2, -z + 2.]
	Fig. 2. (a) The packing in (I), showing the two-dimensional structure parallel to (100). No solvent molecules or H atoms are shown, for clarity. (b) A projection, at right angles to the former view, of the layers shown in (a), as well as their interaction via hydrogen bonding (dashed lines). Note the hydrogen-bonding loops formed, viz. an R6^4(12) ring (denoted A) and an R2^2(*) ring (denoted B). (c) A detailed view of the chain of hydrogen-bonded rings described above, in the same orientation.
	Fig. 3. The Raman (lower line) and IR (upper line) spectra of (I).

Poly[[tetra-µ₃-acetato-hexa-µ₂-acetato-diaqua-µ₂-oxalato- tetrapraseodymium(III)] dihydrate]

Crystal data

[Pr4(C2H3O2)10(C2O4)(H2O)2]·2H2O	F(000) = 1260
Mr = 1314.16	Dx = 2.287 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3988 reflections
a = 9.3772 (3) Å	θ = 4.1–26.7°
b = 13.1249 (3) Å	µ = 5.11 mm^−1
c = 15.9198 (5) Å	T = 291 K
β = 103.085 (3)°	Prism, light green
V = 1908.45 (10) Å^3	0.22 × 0.18 × 0.12 mm
Z = 2

Data collection

Oxford Diffraction Gemini CCD S Ultra diffractometer	4526 independent reflections
Radiation source: fine-focus sealed tube	3935 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.026
ω scans, thick slices	θmax = 29.0°, θmin = 3.8°
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	h = −12→12
Tmin = 0.33, Tmax = 0.54	k = −17→16
14838 measured reflections	l = −21→21

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)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.056	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0277P)^2 + 1.936P] where P = (Fo^2 + 2Fc^2)/3
4526 reflections	(Δ/σ)max = 0.002
256 parameters	Δρmax = 1.07 e Å^−3
6 restraints	Δρmin = −0.90 e Å^−3

Special details

Experimental. The IR vibrational spectrum of a sample of (I) dispersed in KBr pellets was measured using a Fourier transform IR spectrometer NICOLET 8700. The IR spectrum was recorded in the range 400–4000 cm^-1; the Raman spectrum of the crystalline compound was recorded in a Jobin Yvon Horiba labRAM HR.

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.

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

	x	y	z	Uiso*/Ueq
Pr1	0.49231 (2)	0.625935 (13)	0.826748 (12)	0.01932 (6)
Pr2	0.43842 (2)	0.927263 (13)	0.868801 (11)	0.01747 (6)
O11	0.5409 (3)	1.08817 (18)	0.97154 (15)	0.0252 (6)
O21	0.5322 (3)	1.10496 (18)	0.83542 (15)	0.0266 (6)
C11	0.5809 (4)	1.1341 (2)	0.9112 (2)	0.0190 (7)
C21	0.6898 (5)	1.2188 (3)	0.9302 (3)	0.0374 (10)
H21A	0.6411	1.2806	0.9399	0.056*
H21B	0.7347	1.2278	0.8822	0.056*
H21C	0.7636	1.2024	0.9808	0.056*
O12	0.2572 (3)	1.1109 (2)	0.68708 (19)	0.0405 (7)
O22	0.2556 (3)	0.9552 (3)	0.73971 (19)	0.0474 (8)
C12	0.1992 (4)	1.0250 (3)	0.6910 (2)	0.0302 (8)
C22	0.0514 (5)	1.0043 (4)	0.6331 (3)	0.0538 (14)
H22A	0.0488	0.9358	0.6116	0.081*
H22B	0.0342	1.0512	0.5856	0.081*
H22C	−0.0230	1.0126	0.6652	0.081*
O13	0.2999 (3)	0.76939 (18)	0.85145 (16)	0.0275 (6)
O23	0.2250 (3)	0.6465 (2)	0.76030 (18)	0.0343 (6)
C13	0.1970 (4)	0.7248 (3)	0.7987 (2)	0.0251 (8)
C23	0.0459 (5)	0.7641 (4)	0.7828 (4)	0.0531 (13)
H23A	0.0477	0.8347	0.7988	0.080*
H23B	−0.0084	0.7261	0.8166	0.080*
H23C	0.0000	0.7570	0.7228	0.080*
O14	0.5262 (3)	0.79961 (17)	0.76574 (15)	0.0249 (5)
O24	0.5712 (3)	0.95462 (18)	0.73337 (17)	0.0320 (6)
C14	0.5862 (4)	0.8604 (2)	0.7233 (2)	0.0207 (7)
C24	0.6749 (5)	0.8219 (3)	0.6630 (3)	0.0356 (9)
H24A	0.6257	0.8375	0.6047	0.053*
H24B	0.6867	0.7495	0.6695	0.053*
H24C	0.7694	0.8540	0.6760	0.053*
O15	0.6016 (3)	0.75676 (19)	0.93631 (15)	0.0275 (6)
O25	0.7128 (3)	0.90252 (19)	0.92930 (17)	0.0288 (6)
C15	0.7172 (4)	0.8091 (3)	0.9507 (2)	0.0241 (8)
C25	0.8593 (5)	0.7625 (4)	0.9937 (3)	0.0437 (11)
H25A	0.8423	0.7075	1.0299	0.066*
H25B	0.9199	0.8130	1.0282	0.066*
H25C	0.9075	0.7371	0.9508	0.066*
O16	0.3682 (4)	0.4881 (3)	1.05934 (19)	0.0486 (8)
O26	0.3587 (4)	0.5709 (2)	0.93644 (19)	0.0447 (8)
C16	0.4192 (5)	0.5167 (3)	0.9988 (3)	0.0429 (11)
O1W	0.2201 (3)	1.0011 (3)	0.9080 (2)	0.0464 (8)
H1WA	0.236 (4)	1.025 (4)	0.9586 (13)	0.056*
H1WB	0.1286 (14)	1.001 (4)	0.888 (2)	0.056*
O2W	−0.0704 (3)	1.0089 (3)	0.8558 (3)	0.0698 (12)
H2WA	−0.109 (5)	1.054 (3)	0.820 (3)	0.084*
H2WB	−0.139 (4)	0.982 (4)	0.874 (3)	0.084*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pr1	0.02443 (11)	0.01405 (9)	0.01902 (10)	0.00058 (7)	0.00398 (8)	−0.00123 (7)
Pr2	0.02265 (11)	0.01367 (9)	0.01531 (9)	−0.00032 (7)	0.00266 (7)	−0.00124 (6)
O11	0.0338 (15)	0.0226 (12)	0.0202 (13)	−0.0018 (11)	0.0079 (11)	−0.0003 (10)
O21	0.0402 (16)	0.0199 (12)	0.0185 (13)	−0.0058 (11)	0.0044 (11)	−0.0016 (10)
C11	0.0241 (18)	0.0143 (15)	0.0181 (16)	0.0045 (13)	0.0040 (14)	−0.0015 (12)
C21	0.043 (3)	0.035 (2)	0.034 (2)	−0.0188 (19)	0.0071 (19)	−0.0042 (17)
O12	0.0310 (16)	0.0481 (18)	0.0450 (18)	−0.0078 (14)	0.0142 (14)	−0.0092 (14)
O22	0.047 (2)	0.059 (2)	0.0287 (16)	0.0123 (16)	−0.0066 (14)	0.0065 (15)
C12	0.024 (2)	0.043 (2)	0.0230 (19)	0.0003 (18)	0.0043 (16)	−0.0004 (17)
C22	0.037 (3)	0.052 (3)	0.062 (3)	−0.009 (2)	−0.011 (2)	0.014 (2)
O13	0.0294 (15)	0.0226 (13)	0.0294 (14)	−0.0061 (11)	0.0042 (11)	0.0002 (10)
O23	0.0286 (15)	0.0352 (15)	0.0353 (16)	−0.0002 (12)	−0.0005 (12)	−0.0125 (12)
C13	0.024 (2)	0.0233 (18)	0.0280 (19)	−0.0028 (15)	0.0066 (15)	0.0039 (15)
C23	0.027 (2)	0.047 (3)	0.084 (4)	0.000 (2)	0.008 (2)	−0.004 (3)
O14	0.0396 (16)	0.0160 (11)	0.0219 (12)	0.0010 (11)	0.0129 (11)	0.0015 (9)
O24	0.0516 (18)	0.0142 (11)	0.0333 (15)	0.0014 (12)	0.0165 (13)	0.0018 (10)
C14	0.0259 (19)	0.0159 (15)	0.0191 (17)	0.0019 (14)	0.0028 (14)	−0.0004 (12)
C24	0.036 (2)	0.033 (2)	0.045 (2)	0.0041 (18)	0.023 (2)	0.0001 (18)
O15	0.0314 (15)	0.0273 (13)	0.0230 (13)	−0.0053 (11)	0.0041 (11)	−0.0047 (10)
O25	0.0302 (15)	0.0251 (13)	0.0313 (14)	−0.0025 (11)	0.0073 (12)	−0.0024 (11)
C15	0.027 (2)	0.0260 (18)	0.0176 (17)	0.0048 (15)	0.0017 (15)	−0.0048 (14)
C25	0.028 (2)	0.048 (3)	0.050 (3)	0.012 (2)	−0.002 (2)	0.001 (2)
O16	0.053 (2)	0.059 (2)	0.0374 (17)	0.0132 (17)	0.0182 (15)	0.0205 (15)
O26	0.059 (2)	0.0427 (17)	0.0356 (17)	0.0098 (15)	0.0166 (15)	0.0181 (14)
C16	0.071 (3)	0.029 (2)	0.029 (2)	−0.009 (2)	0.012 (2)	0.0002 (17)
O1W	0.0271 (16)	0.069 (2)	0.0395 (18)	0.0102 (16)	−0.0007 (13)	−0.0256 (16)
O2W	0.0287 (18)	0.082 (3)	0.095 (3)	0.0073 (18)	0.0066 (19)	0.049 (2)

Geometric parameters (Å, º)

Pr1—O12^i	2.417 (3)	C22—H22A	0.9600
Pr1—O24^i	2.463 (2)	C22—H22B	0.9600
Pr1—O26	2.476 (3)	C22—H22C	0.9600
Pr1—O16^ii	2.483 (3)	O13—C13	1.270 (4)
Pr1—O23	2.504 (3)	O23—C13	1.254 (4)
Pr1—O15	2.496 (2)	C13—C23	1.475 (6)
Pr1—O14	2.526 (2)	C23—H23A	0.9600
Pr1—O21^i	2.554 (2)	C23—H23B	0.9600
Pr1—O13	2.698 (3)	C23—H23C	0.9600
Pr2—O22	2.388 (3)	O14—C14	1.257 (4)
Pr2—O13	2.428 (2)	O24—C14	1.258 (4)
Pr2—O1W	2.469 (3)	C14—C24	1.494 (5)
Pr2—O11^iii	2.513 (2)	C24—H24A	0.9600
Pr2—O25	2.555 (3)	C24—H24B	0.9600
Pr2—O21	2.590 (2)	C24—H24C	0.9600
Pr2—O14	2.606 (2)	O15—C15	1.260 (4)
Pr2—O11	2.711 (2)	O25—C15	1.271 (4)
Pr2—O24	2.747 (3)	C15—C25	1.485 (5)
Pr2—O15	2.786 (3)	C25—H25A	0.9600
O11—C11	1.261 (4)	C25—H25B	0.9600
O21—C11	1.250 (4)	C25—H25C	0.9600
C11—C21	1.493 (5)	O16—C16	1.227 (5)
C21—H21A	0.9600	O26—C16	1.249 (5)
C21—H21B	0.9600	C16—C16^ii	1.569 (10)
C21—H21C	0.9600	O1W—H1WA	0.85 (3)
O12—C12	1.259 (5)	O1W—H1WB	0.84 (3)
O22—C12	1.239 (5)	O2W—H2WA	0.85 (3)
C12—C22	1.505 (6)	O2W—H2WB	0.85 (3)
O12^i—Pr1—O24^i	92.57 (10)	O11—Pr2—O15	107.72 (7)
O12^i—Pr1—O26	134.27 (10)	O24—Pr2—O15	95.79 (7)
O24^i—Pr1—O26	83.76 (10)	C11—O11—Pr2^iii	147.2 (2)
O12^i—Pr1—O16^ii	69.83 (10)	C11—O11—Pr2	92.25 (19)
O24^i—Pr1—O16^ii	76.98 (10)	Pr2^iii—O11—Pr2	118.89 (9)
O26—Pr1—O16^ii	64.92 (10)	C11—O21—Pr1^iv	150.8 (2)
O12^i—Pr1—O23	150.54 (10)	C11—O21—Pr2	98.3 (2)
O24^i—Pr1—O23	78.67 (9)	Pr1^iv—O21—Pr2	110.33 (9)
O26—Pr1—O23	73.23 (10)	O21—C11—O11	118.8 (3)
O16^ii—Pr1—O23	133.22 (10)	O21—C11—C21	120.5 (3)
O12^i—Pr1—O15	82.30 (10)	O11—C11—C21	120.6 (3)
O24^i—Pr1—O15	157.55 (9)	C11—C21—H21A	109.5
O26—Pr1—O15	84.32 (10)	C11—C21—H21B	109.5
O16^ii—Pr1—O15	80.75 (10)	H21A—C21—H21B	109.5
O23—Pr1—O15	115.73 (8)	C11—C21—H21C	109.5
O12^i—Pr1—O14	80.14 (9)	H21A—C21—H21C	109.5
O24^i—Pr1—O14	135.62 (8)	H21B—C21—H21C	109.5
O26—Pr1—O14	131.47 (9)	C12—O12—Pr1^iv	121.1 (3)
O16^ii—Pr1—O14	137.17 (10)	C12—O22—Pr2	140.7 (3)
O23—Pr1—O14	86.64 (9)	O22—C12—O12	124.4 (4)
O15—Pr1—O14	65.19 (8)	O22—C12—C22	116.9 (4)
O12^i—Pr1—O21^i	76.47 (9)	O12—C12—C22	118.7 (4)
O24^i—Pr1—O21^i	63.29 (8)	C12—C22—H22A	109.5
O26—Pr1—O21^i	137.49 (10)	C12—C22—H22B	109.5
O16^ii—Pr1—O21^i	125.82 (9)	H22A—C22—H22B	109.5
O23—Pr1—O21^i	74.47 (9)	C12—C22—H22C	109.5
O15—Pr1—O21^i	135.17 (8)	H22A—C22—H22C	109.5
O14—Pr1—O21^i	72.48 (8)	H22B—C22—H22C	109.5
O12^i—Pr1—O13	140.02 (9)	C13—O13—Pr2	140.9 (2)
O24^i—Pr1—O13	125.65 (9)	C13—O13—Pr1	90.9 (2)
O26—Pr1—O13	68.82 (9)	Pr2—O13—Pr1	104.70 (9)
O16^ii—Pr1—O13	124.98 (9)	C13—O23—Pr1	100.5 (2)
O23—Pr1—O13	49.30 (8)	O23—C13—O13	119.2 (3)
O15—Pr1—O13	66.44 (8)	O23—C13—C23	120.2 (4)
O14—Pr1—O13	64.71 (7)	O13—C13—C23	120.6 (4)
O21^i—Pr1—O13	108.21 (8)	C13—C23—H23A	109.5
O22—Pr2—O13	76.81 (10)	C13—C23—H23B	109.5
O22—Pr2—O1W	71.47 (11)	H23A—C23—H23B	109.5
O13—Pr2—O1W	84.89 (10)	C13—C23—H23C	109.5
O22—Pr2—O11^iii	139.35 (10)	H23A—C23—H23C	109.5
O13—Pr2—O11^iii	87.88 (8)	H23B—C23—H23C	109.5
O1W—Pr2—O11^iii	69.81 (10)	C14—O14—Pr1	152.9 (2)
O22—Pr2—O25	144.03 (10)	C14—O14—Pr2	99.98 (19)
O13—Pr2—O25	113.68 (8)	Pr1—O14—Pr2	104.65 (8)
O1W—Pr2—O25	140.92 (9)	C14—O24—Pr1^iv	150.6 (2)
O11^iii—Pr2—O25	76.59 (8)	C14—O24—Pr2	93.1 (2)
O22—Pr2—O21	84.03 (10)	Pr1^iv—O24—Pr2	108.16 (9)
O13—Pr2—O21	160.57 (8)	O14—C14—O24	118.6 (3)
O1W—Pr2—O21	92.16 (11)	O14—C14—C24	120.8 (3)
O11^iii—Pr2—O21	109.16 (8)	O24—C14—C24	120.6 (3)
O25—Pr2—O21	80.33 (8)	C14—C24—H24A	109.5
O22—Pr2—O14	79.89 (10)	C14—C24—H24B	109.5
O13—Pr2—O14	67.47 (8)	H24A—C24—H24B	109.5
O1W—Pr2—O14	144.06 (9)	C14—C24—H24C	109.5
O11^iii—Pr2—O14	128.47 (8)	H24A—C24—H24C	109.5
O25—Pr2—O14	73.79 (8)	H24B—C24—H24C	109.5
O21—Pr2—O14	106.23 (8)	C15—O15—Pr1	134.6 (2)
O22—Pr2—O11	119.14 (10)	C15—O15—Pr2	90.4 (2)
O13—Pr2—O11	147.25 (8)	Pr1—O15—Pr2	100.39 (9)
O1W—Pr2—O11	75.10 (9)	C15—O25—Pr2	101.1 (2)
O11^iii—Pr2—O11	61.11 (9)	O15—C15—O25	120.2 (3)
O25—Pr2—O11	71.48 (8)	O15—C15—C25	120.3 (3)
O21—Pr2—O11	48.06 (7)	O25—C15—C25	119.5 (4)
O14—Pr2—O11	139.59 (8)	C15—C25—H25A	109.5
O22—Pr2—O24	70.67 (10)	C15—C25—H25B	109.5
O13—Pr2—O24	110.38 (8)	H25A—C25—H25B	109.5
O1W—Pr2—O24	134.10 (10)	C15—C25—H25C	109.5
O11^iii—Pr2—O24	149.28 (9)	H25A—C25—H25C	109.5
O25—Pr2—O24	73.49 (9)	H25B—C25—H25C	109.5
O21—Pr2—O24	59.06 (7)	C16—O16—Pr1^ii	121.5 (3)
O14—Pr2—O24	47.60 (7)	C16—O26—Pr1	121.0 (3)
O11—Pr2—O24	102.12 (7)	O16—C16—O26	127.6 (5)
O22—Pr2—O15	132.85 (9)	O16—C16—C16^ii	116.2 (5)
O13—Pr2—O15	65.87 (8)	O26—C16—C16^ii	116.1 (5)
O1W—Pr2—O15	129.22 (10)	Pr2—O1W—H1WA	114 (3)
O11^iii—Pr2—O15	68.60 (8)	Pr2—O1W—H1WB	138 (3)
O25—Pr2—O15	48.27 (8)	H1WA—O1W—H1WB	107 (3)
O21—Pr2—O15	128.34 (8)	H2WA—O2W—H2WB	107 (3)
O14—Pr2—O15	60.14 (7)
O22—Pr2—O11—C11	−57.5 (2)	O12^i—Pr1—O14—Pr2	−129.42 (11)
O13—Pr2—O11—C11	−170.1 (2)	O24^i—Pr1—O14—Pr2	147.04 (10)
O1W—Pr2—O11—C11	−115.8 (2)	O26—Pr1—O14—Pr2	12.95 (16)
O11^iii—Pr2—O11—C11	169.3 (3)	O16^ii—Pr1—O14—Pr2	−84.02 (15)
O25—Pr2—O11—C11	84.7 (2)	O23—Pr1—O14—Pr2	77.00 (10)
O21—Pr2—O11—C11	−8.90 (19)	O15—Pr1—O14—Pr2	−43.41 (9)
O14—Pr2—O11—C11	52.7 (2)	O21^i—Pr1—O14—Pr2	151.77 (11)
O24—Pr2—O11—C11	17.0 (2)	O13—Pr1—O14—Pr2	31.01 (8)
O15—Pr2—O11—C11	117.1 (2)	O22—Pr2—O14—C14	77.6 (2)
O22—Pr2—O11—Pr2^iii	133.20 (12)	O13—Pr2—O14—C14	157.4 (2)
O13—Pr2—O11—Pr2^iii	20.6 (2)	O1W—Pr2—O14—C14	114.9 (3)
O1W—Pr2—O11—Pr2^iii	74.86 (13)	O11^iii—Pr2—O14—C14	−135.0 (2)
O11^iii—Pr2—O11—Pr2^iii	0.0	O25—Pr2—O14—C14	−77.6 (2)
O25—Pr2—O11—Pr2^iii	−84.58 (12)	O21—Pr2—O14—C14	−3.1 (2)
O21—Pr2—O11—Pr2^iii	−178.19 (17)	O11—Pr2—O14—C14	−46.0 (3)
O14—Pr2—O11—Pr2^iii	−116.61 (12)	O24—Pr2—O14—C14	4.6 (2)
O24—Pr2—O11—Pr2^iii	−152.34 (11)	O15—Pr2—O14—C14	−128.4 (2)
O15—Pr2—O11—Pr2^iii	−52.15 (12)	O22—Pr2—O14—Pr1	−113.88 (12)
O22—Pr2—O21—C11	147.8 (2)	O13—Pr2—O14—Pr1	−34.07 (9)
O13—Pr2—O21—C11	157.5 (2)	O1W—Pr2—O14—Pr1	−76.63 (19)
O1W—Pr2—O21—C11	76.7 (2)	O11^iii—Pr2—O14—Pr1	33.55 (14)
O11^iii—Pr2—O21—C11	7.4 (2)	O25—Pr2—O14—Pr1	90.90 (10)
O25—Pr2—O21—C11	−64.7 (2)	O21—Pr2—O14—Pr1	165.43 (8)
O14—Pr2—O21—C11	−134.5 (2)	O11—Pr2—O14—Pr1	122.49 (10)
O11—Pr2—O21—C11	9.06 (19)	O24—Pr2—O14—Pr1	173.13 (15)
O24—Pr2—O21—C11	−141.1 (2)	O15—Pr2—O14—Pr1	40.13 (8)
O15—Pr2—O21—C11	−70.1 (2)	O22—Pr2—O24—C14	−98.5 (2)
O22—Pr2—O21—Pr1^iv	−38.18 (12)	O13—Pr2—O24—C14	−31.3 (2)
O13—Pr2—O21—Pr1^iv	−28.6 (3)	O1W—Pr2—O24—C14	−134.5 (2)
O1W—Pr2—O21—Pr1^iv	−109.29 (11)	O11^iii—Pr2—O24—C14	91.9 (2)
O11^iii—Pr2—O21—Pr1^iv	−178.65 (9)	O25—Pr2—O24—C14	78.3 (2)
O25—Pr2—O21—Pr1^iv	109.30 (11)	O21—Pr2—O24—C14	166.8 (2)
O14—Pr2—O21—Pr1^iv	39.45 (12)	O14—Pr2—O24—C14	−4.6 (2)
O11—Pr2—O21—Pr1^iv	−176.97 (16)	O11—Pr2—O24—C14	144.6 (2)
O24—Pr2—O21—Pr1^iv	32.83 (9)	O15—Pr2—O24—C14	35.0 (2)
O15—Pr2—O21—Pr1^iv	103.92 (11)	O22—Pr2—O24—Pr1^iv	60.99 (12)
Pr1^iv—O21—C11—O11	174.9 (3)	O13—Pr2—O24—Pr1^iv	128.15 (10)
Pr2—O21—C11—O11	−16.7 (3)	O1W—Pr2—O24—Pr1^iv	24.99 (17)
Pr1^iv—O21—C11—C21	−7.9 (7)	O11^iii—Pr2—O24—Pr1^iv	−108.63 (15)
Pr2—O21—C11—C21	160.5 (3)	O25—Pr2—O24—Pr1^iv	−122.18 (11)
Pr2^iii—O11—C11—O21	178.3 (3)	O21—Pr2—O24—Pr1^iv	−33.70 (9)
Pr2—O11—C11—O21	15.8 (3)	O14—Pr2—O24—Pr1^iv	154.92 (16)
Pr2^iii—O11—C11—C21	1.1 (6)	O11—Pr2—O24—Pr1^iv	−55.91 (11)
Pr2—O11—C11—C21	−161.4 (3)	O15—Pr2—O24—Pr1^iv	−165.47 (10)
O13—Pr2—O22—C12	164.8 (5)	Pr1—O14—C14—O24	−163.5 (3)
O1W—Pr2—O22—C12	75.8 (4)	Pr2—O14—C14—O24	−8.5 (4)
O11^iii—Pr2—O22—C12	94.2 (5)	Pr1—O14—C14—C24	15.8 (7)
O25—Pr2—O22—C12	−82.9 (5)	Pr2—O14—C14—C24	170.8 (3)
O21—Pr2—O22—C12	−18.5 (4)	Pr1^iv—O24—C14—O14	−129.3 (4)
O14—Pr2—O22—C12	−126.2 (5)	Pr2—O24—C14—O14	8.0 (3)
O11—Pr2—O22—C12	15.7 (5)	Pr1^iv—O24—C14—C24	51.4 (7)
O24—Pr2—O22—C12	−77.7 (4)	Pr2—O24—C14—C24	−171.4 (3)
O15—Pr2—O22—C12	−157.4 (4)	O12^i—Pr1—O15—C15	20.9 (3)
Pr2—O22—C12—O12	19.9 (7)	O24^i—Pr1—O15—C15	98.8 (4)
Pr2—O22—C12—C22	−160.0 (4)	O26—Pr1—O15—C15	157.0 (3)
Pr1^iv—O12—C12—O22	49.3 (5)	O16^ii—Pr1—O15—C15	91.6 (3)
Pr1^iv—O12—C12—C22	−130.8 (4)	O23—Pr1—O15—C15	−134.7 (3)
O22—Pr2—O13—C13	5.7 (4)	O14—Pr1—O15—C15	−61.8 (3)
O1W—Pr2—O13—C13	77.9 (4)	O21^i—Pr1—O15—C15	−41.0 (4)
O11^iii—Pr2—O13—C13	147.8 (4)	O13—Pr1—O15—C15	−133.6 (3)
O25—Pr2—O13—C13	−137.9 (4)	O12^i—Pr1—O15—Pr2	121.87 (10)
O21—Pr2—O13—C13	−4.1 (5)	O24^i—Pr1—O15—Pr2	−160.18 (19)
O14—Pr2—O13—C13	−78.7 (4)	O26—Pr1—O15—Pr2	−101.96 (9)
O11—Pr2—O13—C13	129.8 (3)	O16^ii—Pr1—O15—Pr2	−167.42 (10)
O24—Pr2—O13—C13	−57.6 (4)	O23—Pr1—O15—Pr2	−33.66 (12)
O15—Pr2—O13—C13	−144.8 (4)	O14—Pr1—O15—Pr2	39.22 (8)
O22—Pr2—O13—Pr1	116.03 (11)	O21^i—Pr1—O15—Pr2	59.96 (14)
O1W—Pr2—O13—Pr1	−171.83 (11)	O13—Pr1—O15—Pr2	−32.61 (7)
O11^iii—Pr2—O13—Pr1	−101.92 (9)	O22—Pr2—O15—C15	131.8 (2)
O25—Pr2—O13—Pr1	−27.57 (11)	O13—Pr2—O15—C15	172.6 (2)
O21—Pr2—O13—Pr1	106.2 (2)	O1W—Pr2—O15—C15	−126.8 (2)
O14—Pr2—O13—Pr1	31.65 (8)	O11^iii—Pr2—O15—C15	−89.8 (2)
O11—Pr2—O13—Pr1	−119.88 (13)	O25—Pr2—O15—C15	1.09 (18)
O24—Pr2—O13—Pr1	52.76 (11)	O21—Pr2—O15—C15	8.2 (2)
O15—Pr2—O13—Pr1	−34.47 (8)	O14—Pr2—O15—C15	95.7 (2)
O12^i—Pr1—O13—C13	141.0 (2)	O11—Pr2—O15—C15	−41.9 (2)
O24^i—Pr1—O13—C13	−19.2 (2)	O24—Pr2—O15—C15	62.9 (2)
O26—Pr1—O13—C13	−84.3 (2)	O22—Pr2—O15—Pr1	−3.88 (16)
O16^ii—Pr1—O13—C13	−118.6 (2)	O13—Pr2—O15—Pr1	36.97 (8)
O23—Pr1—O13—C13	1.41 (19)	O1W—Pr2—O15—Pr1	97.53 (11)
O15—Pr1—O13—C13	−177.3 (2)	O11^iii—Pr2—O15—Pr1	134.55 (10)
O14—Pr1—O13—C13	110.1 (2)	O25—Pr2—O15—Pr1	−134.55 (13)
O21^i—Pr1—O13—C13	50.5 (2)	O21—Pr2—O15—Pr1	−127.43 (9)
O12^i—Pr1—O13—Pr2	−2.67 (18)	O14—Pr2—O15—Pr1	−39.91 (8)
O24^i—Pr1—O13—Pr2	−162.91 (8)	O11—Pr2—O15—Pr1	−177.50 (7)
O26—Pr1—O13—Pr2	132.00 (12)	O24—Pr2—O15—Pr1	−72.79 (9)
O16^ii—Pr1—O13—Pr2	97.68 (12)	O22—Pr2—O25—C15	−109.9 (2)
O23—Pr1—O13—Pr2	−142.29 (14)	O13—Pr2—O25—C15	−9.6 (2)
O15—Pr1—O13—Pr2	38.96 (9)	O1W—Pr2—O25—C15	103.1 (2)
O14—Pr1—O13—Pr2	−33.57 (8)	O11^iii—Pr2—O25—C15	72.0 (2)
O21^i—Pr1—O13—Pr2	−93.18 (10)	O21—Pr2—O25—C15	−175.4 (2)
O12^i—Pr1—O23—C13	−123.6 (3)	O14—Pr2—O25—C15	−65.3 (2)
O24^i—Pr1—O23—C13	161.6 (2)	O11—Pr2—O25—C15	135.7 (2)
O26—Pr1—O23—C13	74.7 (2)	O24—Pr2—O25—C15	−115.0 (2)
O16^ii—Pr1—O23—C13	101.8 (2)	O15—Pr2—O25—C15	−1.10 (19)
O15—Pr1—O23—C13	−0.2 (3)	Pr1—O15—C15—O25	103.2 (4)
O14—Pr1—O23—C13	−60.5 (2)	Pr2—O15—C15—O25	−1.9 (3)
O21^i—Pr1—O23—C13	−133.3 (2)	Pr1—O15—C15—C25	−77.6 (4)
O13—Pr1—O23—C13	−1.5 (2)	Pr2—O15—C15—C25	177.3 (3)
Pr1—O23—C13—O13	2.7 (4)	Pr2—O25—C15—O15	2.1 (4)
Pr1—O23—C13—C23	−177.1 (3)	Pr2—O25—C15—C25	−177.1 (3)
Pr2—O13—C13—O23	112.4 (4)	O12^i—Pr1—O26—C16	−6.2 (4)
Pr1—O13—C13—O23	−2.4 (3)	O24^i—Pr1—O26—C16	81.3 (3)
Pr2—O13—C13—C23	−67.8 (5)	O16^ii—Pr1—O26—C16	2.8 (3)
Pr1—O13—C13—C23	177.3 (3)	O23—Pr1—O26—C16	161.3 (3)
O12^i—Pr1—O14—C14	25.1 (5)	O15—Pr1—O26—C16	−79.6 (3)
O24^i—Pr1—O14—C14	−58.5 (5)	O14—Pr1—O26—C16	−129.0 (3)
O26—Pr1—O14—C14	167.4 (5)	O21^i—Pr1—O26—C16	119.3 (3)
O16^ii—Pr1—O14—C14	70.5 (5)	O13—Pr1—O26—C16	−146.5 (3)
O23—Pr1—O14—C14	−128.5 (5)	Pr1^ii—O16—C16—O26	177.5 (3)
O15—Pr1—O14—C14	111.1 (5)	Pr1^ii—O16—C16—C16^ii	−4.0 (6)
O21^i—Pr1—O14—C14	−53.7 (5)	Pr1—O26—C16—O16	176.5 (4)
O13—Pr1—O14—C14	−174.5 (5)	Pr1—O26—C16—C16^ii	−2.0 (6)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O25^iii	0.85 (3)	1.98 (3)	2.823 (4)	172 (5)
O1W—H1WB···O2W	0.84 (3)	1.82 (2)	2.664 (4)	174 (4)
O2W—H2WA···O23^v	0.84 (3)	1.91 (3)	2.751 (4)	171 (5)
O2W—H2WB···O25^vi	0.85 (3)	2.08 (3)	2.920 (4)	173 (5)

Symmetry codes: (iii) −x+1, −y+2, −z+2; (v) −x, y+1/2, −z+3/2; (vi) x−1, y, z.