3-(2-Formyl­phen­oxy)propanoic acid

Collas, A.; Vande Velde, C.M.L.; Blockhuys, F.

doi:10.1107/S1600536810038079

organic compounds

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ISSN: 2056-9890

Volume 66| Part 10| October 2010| Page o2662

doi:10.1107/S1600536810038079

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3-(2-Formylphenoxy)propanoic acid

Alain Collas,^a Christophe M. L. Vande Velde ^a ‡ and Frank Blockhuys ^a ^*

^aDepartment of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk, Belgium
^*Correspondence e-mail: frank.blockhuys@ua.ac.be

(Received 13 September 2010; accepted 23 September 2010; online 30 September 2010)

In the structure of the title compound, C₁₀H₁₀O₄, the carboxyl group forms a catemer motif in the [100] direction instead of the expected dimeric structures. The carboxylic acid group is found in the syn conformation and the three-dimensional organization in the crystal is based on C—H⋯O and O—H⋯O interactions.

Related literature

For the synthesis, see: Zawadowska (1963 ); Jarvest et al. (2005 ). For related structures, see: Gresham et al. (1949 ); Leiserowitz (1976 ); Borthwick (1980 ); Kennard et al. (1982 ); Shockravi et al. (2004 ); Gao & Ng (2006 ). For applications of poly(p-phenylene vinylene) oligomers (PPVs), see: Chemla (1987 ); Bandyopadhyay & Pal (2003 ). For hydrogen bonding and crystal engineering, see: Desiraju (1997 ); Steiner (2002 ).

Experimental

Crystal data

C₁₀H₁₀O₄
M_r = 194.18
Orthorhombic, P b c a
a = 15.269 (4) Å
b = 7.167 (2) Å
c = 17.136 (5) Å
V = 1875.2 (9) Å³
Z = 8
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 293 K
0.42 × 0.21 × 0.15 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
1718 measured reflections
1718 independent reflections
964 reflections with I > 2σ(I)
3 standard reflections every 60 min intensity decay: 1%

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.119
S = 1.02
1718 reflections
167 parameters
All H-atom parameters refined
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H41⋯O4ⁱ	0.94 (4)	1.72 (4)	2.618 (3)	158 (3)
C21—H21a⋯O1ⁱⁱ	1.00 (3)	2.64 (3)	3.409 (4)	134.5 (2)
C22—H22b⋯O1ⁱⁱⁱ	0.96 (3)	2.46 (3)	3.187 (4)	132 (2)
C21—H21a⋯O3^iv	1.00 (3)	2.60 (2)	3.456 (3)	144 (2)
C3—H3⋯O4^v	0.96 (2)	2.71 (2)	3.536 (4)	144.9 (2)
Symmetry codes: (i) $[-x-{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ ; (ii) -x, -y+1, -z+1; (iii) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iv) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (v) $[x+{\script{1\over 2}}, y, -z+{\script{1\over 2}}]$ .

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810038079/zl2308sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810038079/zl2308Isup2.hkl

checkCIF report

Comment top

The title compound was synthesized as a precursor for asymmetric PPV-type [poly(p-phenylene vinylene)] oligomers. These compounds are promising candidates as the active materials in organic memories (Bandyopadhyay & Pal, 2003) and as non-linear optical (NLO) materials with a high first-order hyperpolarizability (Chemla, 1987). Besides the condition that these oligomers should bear donor and acceptor substituents connected by a π-system, it is of critical importance for their usefulness as an NLO material and as a bistable organic memory material that the crystal packing is non-centrosymmetric. In particular, the compound should crystallize in a polar space group. To influence the crystal packing by means of the crystal engineering methodology in order to meet this criterion, it is necessary to introduce certain statistically well chosen synthons (Desiraju, 1997). Therefore, we opted for carboxylic acid functional groups (powerful hydrogen bond donors) in the basic structure of the organic semiconductor. To combine the electronic (A-π-D) and the structural (non-centrosymmetric space group) requirements, we used the Williamson ether synthesis to prepare the title compound as a building block for a PPV-based semiconductor bearing a carboxylic acid moiety.

The geometry of the aldehyde contains no surprises. The methylene fragments are in synclinal conformation and the torsion angle is 65.9 (3)°. As a result and due to the repulsion between the lone pairs of oxygen atoms O2 and O3, the carboxylic acid group, found in the syn conformation, is twisted out of the plane of the phenyl ring. The O2···O3 distance is 3.034 (3) Å and this is the only contact of the ether oxygen atom. The distances in the carboxylic acid moiety are in accordance with the expected values for non-disordered carboxylic acids (Leiserowitz, 1976): the carbonyl (C=O) bond length C23—O4 is 1.209 (3) Å and the C—O single bond length C23—O3 is 1.306 (3) Å. The angles of the carboxyl moiety contain no surprises (Borthwick, 1980): C23—O3—H31 is 110 (2)° and O4—C23—O3 is 121.9 (2)°.

Two intramolecular CH···O hydrogen bonds involving the aldehyde group can be identified: the relevant parameters of C6—H6···O1 and C11—H1···O2 are given in Table 1, entries 1 and 2. The incorporation of a carboxylic acid group was expected to yield the corresponding dimer synthon, but the crystal structure of the title compound reveals a catemer motif in the [1 0 0] direction (Fig. 2), consisting of an infinite chain of hydrogen bonds. The O3···O4 distance is 2.618 (3) Å (Table 1, entry 3) which is not surprising for a hydrogen bond of moderate strength (Steiner, 2002). The chains are intertwined through O1···Cg contacts in which the aldehyde oxygen atom contacts the center of the aromatic ring [O1···Cgⁱ 3.508 (3) Å, C11—O1···Cgⁱ 78.47 (17)°, symm. code i = 1-x, -y, -z]. O1 is also involved in weak CH···O hydrogen bonds with H21a (Table 1, entry 4) and H22b (Table 1, entry 5); the latter links the infinite hydrogen bonded chains in the [0 0 1] direction (Fig. 3). Two additional hydrogen bonds can be observed: H21a contacts O3 and H3 contacts O4 (Table 1, entries 6 and 7, respectively).

Related literature top

For the synthesis, see: Zawadowska (1963); Jarvest et al. (2005). For related structures, see: Gresham et al. (1949); Leiserowitz (1976); Borthwick (1980); Kennard et al. (1982); Shockravi et al. (2004); Gao & Ng (2006). For applications of poly(p-phenylene vinylene) oligomers (PPVs), see: Chemla (1987); Bandyopadhyay & Pal (2003). For hydrogen bonding and crystal engineering, see: Desiraju (1997); Steiner (2002).

Experimental top

Salicylic aldehyde and 3-chloropropanoic acid were obtained from ACROS and used as received. The general procedure of Gresham was followed (Gresham et al., 1949). 8 g of NaOH in 20 ml of distilled water were added to a stirred solution of 12.2 g (0.1 mol) of salicylic aldehyde and 10.9 g (0.1 mol) of 3-chloropropanoic acid in 80 ml of distilled water. After heating under reflux for 4 h, the mixture was acidified with 19.5 ml of conc. HCl. Unreacted salicylic aldehyde was removed by steam distillation and the resulting mixture was placed in the refrigerator. The resulting tan-coloured needles were collected by filtration in a 20% yield. M.p. 381 K (uncorrected). Crystals suitable for the diffraction experiment were grown by slow evaporation of a 50:50 chloroform:toluene solvent mixture, analogous with the experiments of Kennard (Kennard et al., 1981). ¹H NMR (CD₃OD, 400 MHz, TMS): δ 2.84 (t, 2H, 6.00 Hz, H22), 4.39 (t, 2H, 6.00 Hz, H21), 7.05 (td, 1H, 7.44 and 0.88 Hz, H5), 7.18 (d, 1H, 8.10 Hz, H3), 7.61 (td, 1H, 7.32 and 1.88 Hz, H4), 7.75 (dd, 1H, 7.72 and 1.80 Hz, H6), 10.39 (d, 1H, 0.80 Hz, H21b); the proton of the carboxylic acid can not be seen. ¹³C NMR (CDCl₃, 100 MHz, TMS): δ 34.17 (C22), 63.83 (C21), 112.66 (C3), 121.33 (C5), 125.08 (C1), 128.61 (C6), 135.99 (C4), 160.75 (C2), 175.97 (C11), 189.79 (C23).

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. Molecular structure of the title compound with the numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and hydrogen atoms are represented as spheres with an arbitrary radius.
	Fig. 2. Representation of the infinite chain of hydrogen bonds involving the carboxyl moiety through the crystal structure of the title compound. See Table 1 for details.
	Fig. 3. Additional short contacts in the crystal structure of the title compound. See Table 1 for details.

3-(2-formylphenoxy)propanoic acid top

Crystal data top

C₁₀H₁₀O₄	D_x = 1.376 Mg m⁻³
M_r = 194.18	Melting point: 381 K
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 25 reflections
a = 15.269 (4) Å	θ = 6.2–19.0°
b = 7.167 (2) Å	µ = 0.11 mm⁻¹
c = 17.136 (5) Å	T = 293 K
V = 1875.2 (9) Å³	Block, colourless
Z = 8	0.42 × 0.21 × 0.15 mm
F(000) = 816

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.000
Radiation source: fine-focus sealed tube	θ_max = 25.3°, θ_min = 2.4°
Graphite monochromator	h = −18→0
ω/2θ scans	k = −8→0
1718 measured reflections	l = 0→20
1718 independent reflections	3 standard reflections every 60 min
964 reflections with I > 2σ(I)	intensity decay: 1%

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.119	All H-atom parameters refined
S = 1.02	w = 1/[σ²(F_o²) + (0.0516P)²] where P = (F_o² + 2F_c²)/3
1718 reflections	(Δ/σ)_max < 0.001
167 parameters	Δρ_max = 0.17 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₁₀H₁₀O₄	V = 1875.2 (9) Å³
M_r = 194.18	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 15.269 (4) Å	µ = 0.11 mm⁻¹
b = 7.167 (2) Å	T = 293 K
c = 17.136 (5) Å	0.42 × 0.21 × 0.15 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.000
1718 measured reflections	3 standard reflections every 60 min
1718 independent reflections	intensity decay: 1%
964 reflections with I > 2σ(I)

Refinement top

R[F² > 2σ(F²)] = 0.047	0 restraints
wR(F²) = 0.119	All H-atom parameters refined
S = 1.02	Δρ_max = 0.17 e Å⁻³
1718 reflections	Δρ_min = −0.21 e Å⁻³
167 parameters

Special details top

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
H21a	0.0220 (14)	0.495 (4)	0.3039 (14)	0.049 (7)*
H22b	−0.1019 (16)	0.478 (4)	0.2296 (16)	0.063 (9)*
H22a	−0.1276 (16)	0.540 (4)	0.3140 (14)	0.058 (9)*
H21b	0.0046 (17)	0.281 (4)	0.2824 (15)	0.058 (8)*
H5	0.2323 (19)	0.109 (4)	0.5447 (16)	0.073 (10)*
H3	0.1355 (15)	0.315 (4)	0.3435 (14)	0.049 (8)*
H41	−0.1930 (19)	0.040 (6)	0.2804 (19)	0.104 (13)*
H4	0.2503 (19)	0.196 (4)	0.4169 (15)	0.058 (9)*
H6	0.092 (2)	0.133 (4)	0.6011 (18)	0.081 (11)*
H1	−0.100 (2)	0.276 (4)	0.5065 (19)	0.099 (12)*
O3	−0.14623 (11)	0.1255 (3)	0.28392 (12)	0.0509 (6)
O2	−0.02664 (10)	0.3422 (3)	0.39246 (10)	0.0464 (5)
O4	−0.25446 (11)	0.3279 (2)	0.28021 (11)	0.0562 (6)
C23	−0.17679 (16)	0.2958 (3)	0.28326 (14)	0.0384 (6)
C2	0.04663 (17)	0.2827 (3)	0.43064 (16)	0.0414 (7)
C1	0.03508 (17)	0.2307 (4)	0.50805 (16)	0.0443 (7)
C21	−0.01910 (17)	0.3884 (4)	0.31172 (16)	0.0426 (7)
O1	−0.06445 (15)	0.2082 (3)	0.61361 (12)	0.0779 (7)
C22	−0.10849 (17)	0.4449 (4)	0.28378 (19)	0.0421 (7)
C3	0.12868 (17)	0.2735 (4)	0.39650 (18)	0.0511 (8)
C6	0.1071 (2)	0.1672 (5)	0.5502 (2)	0.0625 (9)
C11	−0.0514 (2)	0.2416 (4)	0.54553 (18)	0.0565 (8)
C4	0.1983 (2)	0.2109 (5)	0.4398 (2)	0.0690 (10)
C5	0.1876 (2)	0.1563 (6)	0.5161 (2)	0.0761 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O3	0.0400 (10)	0.0306 (11)	0.0823 (15)	0.0022 (8)	0.0009 (11)	0.0024 (10)
O2	0.0428 (10)	0.0563 (12)	0.0401 (11)	0.0032 (9)	0.0023 (9)	0.0062 (10)
O4	0.0409 (10)	0.0359 (10)	0.0919 (15)	0.0035 (9)	−0.0046 (11)	−0.0016 (11)
C23	0.0428 (15)	0.0324 (14)	0.0401 (15)	0.0047 (12)	0.0018 (13)	0.0013 (12)
C2	0.0481 (16)	0.0314 (14)	0.0449 (17)	−0.0040 (12)	−0.0047 (13)	−0.0030 (12)
C1	0.0533 (18)	0.0353 (15)	0.0442 (17)	−0.0071 (13)	−0.0018 (13)	−0.0035 (13)
C21	0.0438 (16)	0.0416 (17)	0.0424 (16)	−0.0065 (14)	0.0018 (13)	0.0020 (14)
O1	0.1120 (18)	0.0752 (16)	0.0466 (14)	−0.0116 (14)	0.0176 (12)	0.0007 (12)
C22	0.0500 (16)	0.0312 (16)	0.0451 (18)	−0.0034 (12)	−0.0004 (15)	0.0009 (14)
C3	0.0437 (16)	0.0558 (18)	0.0537 (19)	−0.0044 (14)	−0.0007 (16)	0.0009 (16)
C6	0.075 (2)	0.059 (2)	0.054 (2)	−0.0036 (18)	−0.011 (2)	−0.0018 (17)
C11	0.077 (2)	0.0448 (19)	0.047 (2)	−0.0066 (17)	0.0067 (18)	−0.0035 (15)
C4	0.0453 (19)	0.084 (3)	0.077 (3)	0.0022 (18)	−0.0088 (19)	−0.009 (2)
C5	0.072 (3)	0.080 (3)	0.077 (3)	0.009 (2)	−0.031 (2)	0.000 (2)

Geometric parameters (Å, º) top

O3—C23	1.306 (3)	C21—H21b	0.99 (3)
O3—H41	0.95 (4)	O1—C11	1.208 (3)
O2—C2	1.364 (3)	C22—H22b	0.96 (3)
O2—C21	1.427 (3)	C22—H22a	0.90 (3)
O4—C23	1.209 (3)	C3—C4	1.371 (4)
C23—C22	1.493 (3)	C3—H3	0.96 (2)
C2—C3	1.384 (4)	C6—C5	1.363 (5)
C2—C1	1.389 (4)	C6—H6	0.93 (3)
C1—C6	1.392 (4)	C11—H1	1.03 (3)
C1—C11	1.471 (4)	C4—C5	1.375 (5)
C21—C22	1.502 (4)	C4—H4	0.89 (3)
C21—H21a	1.00 (3)	C5—H5	0.91 (3)

C23—O3—H41	110 (2)	C21—C22—H22b	106.2 (15)
C2—O2—C21	118.1 (2)	C23—C22—H22a	108.5 (17)
O4—C23—O3	121.9 (2)	C21—C22—H22a	108.3 (17)
O4—C23—C22	123.3 (2)	H22b—C22—H22a	113 (2)
O3—C23—C22	114.8 (2)	C4—C3—C2	119.2 (3)
O2—C2—C3	123.7 (3)	C4—C3—H3	121.8 (14)
O2—C2—C1	116.0 (2)	C2—C3—H3	118.9 (15)
C3—C2—C1	120.4 (3)	C5—C6—C1	120.6 (4)
C6—C1—C2	118.9 (3)	C5—C6—H6	127 (2)
C6—C1—C11	120.0 (3)	C1—C6—H6	112.3 (19)
C2—C1—C11	121.1 (3)	O1—C11—C1	124.0 (3)
O2—C21—C22	107.3 (2)	O1—C11—H1	123.9 (19)
O2—C21—H21a	111.0 (14)	C1—C11—H1	112.0 (19)
C22—C21—H21a	108.9 (14)	C3—C4—C5	121.0 (3)
O2—C21—H21b	110.0 (16)	C3—C4—H4	119.5 (18)
C22—C21—H21b	112.4 (15)	C5—C4—H4	119.2 (18)
H21a—C21—H21b	107 (2)	C6—C5—C4	119.9 (4)
C23—C22—C21	116.3 (2)	C6—C5—H5	118.0 (19)
C23—C22—H22b	104.2 (16)	C4—C5—H5	122.1 (19)

C21—O2—C2—C3	3.4 (4)	O2—C2—C3—C4	−179.7 (3)
C21—O2—C2—C1	−176.9 (2)	C1—C2—C3—C4	0.6 (4)
O2—C2—C1—C6	179.5 (2)	C2—C1—C6—C5	0.0 (4)
C3—C2—C1—C6	−0.8 (4)	C11—C1—C6—C5	179.9 (3)
O2—C2—C1—C11	−0.4 (4)	C6—C1—C11—O1	4.3 (4)
C3—C2—C1—C11	179.3 (3)	C2—C1—C11—O1	−175.8 (3)
C2—O2—C21—C22	178.8 (2)	C2—C3—C4—C5	0.4 (5)
O4—C23—C22—C21	162.1 (3)	C1—C6—C5—C4	1.0 (5)
O3—C23—C22—C21	−20.0 (4)	C3—C4—C5—C6	−1.2 (6)
O2—C21—C22—C23	−65.9 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O1	0.94 (3)	2.46 (3)	2.851 (4)	105 (2)
C11—H1···O2	1.03 (3)	2.30 (3)	2.746 (4)	105 (2)
O3—H41···O4ⁱ	0.94 (4)	1.72 (4)	2.618 (3)	158 (3)
C21—H21a···O1ⁱⁱ	1.00 (3)	2.64 (3)	3.409 (4)	134.5 (2)
C22—H22b···O1ⁱⁱⁱ	0.96 (3)	2.46 (3)	3.187 (4)	132 (2)
C21—H21a···O3^iv	1.00 (3)	2.60 (2)	3.456 (3)	144 (2)
C3—H3···O4^v	0.96 (2)	2.71 (2)	3.536 (4)	144.9 (2)

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

Experimental details

Crystal data
Chemical formula	C₁₀H₁₀O₄
M_r	194.18
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	293
a, b, c (Å)	15.269 (4), 7.167 (2), 17.136 (5)
V (Å³)	1875.2 (9)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.42 × 0.21 × 0.15

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	1718, 1718, 964
R_int	0.000
(sin θ/λ)_max (Å⁻¹)	0.602

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.119, 1.02
No. of reflections	1718
No. of parameters	167
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.21

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H41···O4ⁱ	0.94 (4)	1.72 (4)	2.618 (3)	158 (3)
C21—H21a···O1ⁱⁱ	1.00 (3)	2.64 (3)	3.409 (4)	134.5 (2)
C22—H22b···O1ⁱⁱⁱ	0.96 (3)	2.46 (3)	3.187 (4)	132 (2)
C21—H21a···O3^iv	1.00 (3)	2.60 (2)	3.456 (3)	144 (2)
C3—H3···O4^v	0.96 (2)	2.71 (2)	3.536 (4)	144.9 (2)

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

Footnotes

‡Current address: Karel de Grote University College, Department of Applied Engineering, Salesianenlaan 30, B-2660 Antwerp, Belgium.

Acknowledgements

CVV thanks the Fund for Scientific Research (FWO Vlaanderen) for a grant as a research assistant. AC wishes to thank the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT) for a predoctoral grant.

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