Dimethyl 3,3′-di­meth­oxy­biphenyl-4,4′-di­carboxyl­ate

Lundvall, F.; Wragg, D.S.; Dietzel, P.D.C.; Fjellvåg, H.

doi:10.1107/S1600536814005613

organic compounds

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ISSN: 2056-9890

Volume 70| Part 4| April 2014| Page o449

doi:10.1107/S1600536814005613

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Dimethyl 3,3′-dimethoxybiphenyl-4,4′-dicarboxylate

Fredrik Lundvall,^a ^* David Stephen Wragg,^a,^b Pascal D. C. Dietzel ^c and Helmer Fjellvåg ^a

^aCentre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, PO Box 1126, 0315 Oslo, Norway, ^binGAP National Centre of Research-based Innovation, Department of Chemistry, University of Oslo, PO Box 1126, 0315 Oslo, Norway, and ^cDepartment of Chemistry, University of Bergen, PO Box 7803, 5020 Bergen, Norway
^*Correspondence e-mail: fredrik.lundvall@smn.uio.no

(Received 5 March 2014; accepted 12 March 2014; online 15 March 2014)

In the title compound, C₁₈H₁₈O₆, the biphenyl moiety is twisted with a dihedral angle of 29.11 (10)°. The carbomethoxy groups form C—C—C—O torsion angles of −18.3 (3) and −27.7 (3)° with the attached rings, as a result of steric hindrances from the nearby methoxy groups. In the absence of stacking interactions and with no H⋯O contacts shorter than 2.7 Å, the packing is dominated by weaker van der Waals interactions.

CCDC reference: 991339

Related literature

For the synthesis, see Zhou et al. (2007 ).

Experimental

Crystal data

C₁₈H₁₈O₆
M_r = 330.32
Monoclinic, P 2₁ /c
a = 12.9320 (6) Å
b = 7.3736 (4) Å
c = 16.4203 (8) Å
β = 97.410 (2)°
V = 1552.69 (13) Å³
Z = 4
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 297 K
0.23 × 0.17 × 0.06 mm

Data collection

Bruker PHOTON CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.976, T_max = 0.994
14813 measured reflections
2830 independent reflections
2023 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.051
wR(F²) = 0.143
S = 1.02
2830 reflections
217 parameters
H-atom parameters constrained
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Selected torsion angles (°)

C2—C1—C7—C8	28.9 (3)
C3—C4—C13—O1	−27.7 (3)
C11—C10—C14—O4	−18.3 (3)

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ) and WinGX (Farrugia, 2012 ); molecular graphics: DIAMOND (Brandenburg, 2004 ) and ChemBioDraw Ultra (CambridgeSoft, 2009 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 991339

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S1600536814005613/ld2122sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814005613/ld2122Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814005613/ld2122Isup3.cml

checkCIF report

Comment top

The title compound is an intermediate in the synthesis of 3,3'-dimethoxy-4,4'-biphenyldicarboxylic acid, an organic linker for use in the synthesis of MOFs (Metal-Organic Frameworks). The title compound has previously been reported (Zhou et al., 2007), but its crystal structure was unknown until this publication.

There is a twist between benzene rings, which is a common feature in biphenyl compounds. The methoxy substituents are nearly coplanar with their parent benzene rings. On the opposite, the methyl carboxylate substituents are not co-planar with the adjacent benzene rings, and the corresponding dihedral angles differ between the two halves of the molecule. The methyl groups of the methoxy and methyl carboxylate substituents are oriented away from each other to accommodate the sterical demands of these groups. The long axis of the molecules is oriented in the [101] direction and two-dimensional corrugated layers parallel to the ac plane can be imagined. The packing does not appear to be directed by any strong intermolecular bonding, although some long range interaction might influence the ordering of the molecules. Indeed, the carbonyl O atoms O5 and O2 are oriented towards H12 and H2 of neighbouring molecules in a near linear fashion. However, since the O—H distances are very long (>2.7 Å), they are unlikely to be a major factor in the crystal packing.

Related literature top

For the synthesis, see Zhou et al. (2007).

Experimental top

The title compound was synthesized by a slightly modified version of the method used by Zhou et al. (2007). In the Ullmann-coupling of 2 equivalents of methyl 4-iodo-2-methoxybenzoate to form the title compound, the reaction temperature was increased to 225 °C and the reaction time was set to 8 h. The title compound was extracted from the reaction mixture by repeated washing with warm ethyl acetate and subsequent filtering to remove solid particles. The resulting ¹H NMR spectrum is in good agreement with what was reported by Zhou et al. (2007).

Single crystals suitable for XRD analysis were obtained by recrystallizing the title compound from ethyl acetate.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and WinGX (Farrugia, 2012); molecular graphics: DIAMOND (Brandenburg, 2004) and ChemBioDraw Ultra (CambridgeSoft, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

Fig. 1. The molecule of the title compound with atom labels and 50% probability displacement ellipsoids. Hydrogen atoms are omitted for clarity.

Dimethyl 3,3'-dimethoxybiphenyl-4,4'-dicarboxylate top

Crystal data top

C₁₈H₁₈O₆	F(000) = 696
M_r = 330.32	D_x = 1.413 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5300 reflections
a = 12.9320 (6) Å	θ = 2.5–25.3°
b = 7.3736 (4) Å	µ = 0.11 mm⁻¹
c = 16.4203 (8) Å	T = 297 K
β = 97.410 (2)°	Plate, colourless
V = 1552.69 (13) Å³	0.23 × 0.17 × 0.06 mm
Z = 4

Data collection top

Bruker PHOTON CCD diffractometer	2830 independent reflections
Radiation source: fine-focus sealed tube	2023 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
ϕ and ω scans	θ_max = 25.4°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −15→15
T_min = 0.976, T_max = 0.994	k = −8→8
14813 measured reflections	l = −19→19

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)] = 0.051	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.143	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0692P)² + 0.5584P] where P = (F_o² + 2F_c²)/3
2830 reflections	(Δ/σ)_max = 0.001
217 parameters	Δρ_max = 0.30 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₁₈H₁₈O₆	V = 1552.69 (13) Å³
M_r = 330.32	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 12.9320 (6) Å	µ = 0.11 mm⁻¹
b = 7.3736 (4) Å	T = 297 K
c = 16.4203 (8) Å	0.23 × 0.17 × 0.06 mm
β = 97.410 (2)°

Data collection top

Bruker PHOTON CCD diffractometer	2830 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2023 reflections with I > 2σ(I)
T_min = 0.976, T_max = 0.994	R_int = 0.031
14813 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.051	0 restraints
wR(F²) = 0.143	H-atom parameters constrained
S = 1.02	Δρ_max = 0.30 e Å⁻³
2830 reflections	Δρ_min = −0.21 e Å⁻³
217 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
C1	0.65055 (14)	0.1733 (3)	0.91869 (11)	0.0393 (5)
C2	0.54757 (14)	0.2196 (3)	0.92368 (11)	0.0403 (5)
H2	0.5274	0.2458	0.9747	0.048*
C3	0.47394 (14)	0.2277 (3)	0.85443 (11)	0.0381 (5)
C4	0.50301 (15)	0.1825 (3)	0.77713 (11)	0.0408 (5)
C5	0.60636 (15)	0.1385 (3)	0.77293 (12)	0.0457 (5)
H5	0.6270	0.1114	0.7221	0.055*
C6	0.67954 (15)	0.1336 (3)	0.84176 (12)	0.0466 (5)
H6	0.7484	0.1038	0.8369	0.056*
C7	0.72881 (14)	0.1687 (3)	0.99378 (11)	0.0399 (5)
C8	0.70005 (15)	0.1301 (3)	1.07078 (11)	0.0465 (5)
H8	0.6307	0.1059	1.0763	0.056*
C9	0.77472 (15)	0.1280 (3)	1.13896 (11)	0.0457 (5)
H9	0.7543	0.1020	1.1899	0.055*
C10	0.87902 (15)	0.1633 (3)	1.13416 (11)	0.0401 (5)
C11	0.90801 (14)	0.2030 (3)	1.05639 (11)	0.0398 (5)
C12	0.83282 (14)	0.2061 (3)	0.98785 (11)	0.0404 (5)
H12	0.8526	0.2338	0.9368	0.048*
C13	0.43182 (15)	0.1785 (3)	0.69788 (11)	0.0420 (5)
C14	0.95062 (15)	0.1569 (3)	1.21280 (12)	0.0450 (5)
C15	0.26093 (16)	0.1350 (4)	0.63245 (12)	0.0577 (6)
H15A	0.2837	0.0440	0.5969	0.087*
H15B	0.2584	0.2505	0.6054	0.087*
H15C	0.1928	0.1045	0.6454	0.087*
C16	1.12175 (16)	0.1390 (4)	1.27938 (12)	0.0630 (7)
H16A	1.1179	0.2521	1.3078	0.094*
H16B	1.1912	0.1218	1.2661	0.094*
H16C	1.1043	0.0415	1.3139	0.094*
C17	0.34918 (16)	0.3548 (4)	0.93227 (12)	0.0585 (6)
H17A	0.3545	0.2607	0.9730	0.088*
H17B	0.2793	0.4014	0.9245	0.088*
H17C	0.3969	0.4508	0.9502	0.088*
C18	1.04057 (16)	0.2687 (4)	0.97237 (12)	0.0604 (7)
H18A	1.0198	0.1664	0.9380	0.091*
H18B	1.1149	0.2826	0.9772	0.091*
H18C	1.0076	0.3763	0.9485	0.091*
O1	0.33324 (10)	0.1438 (2)	0.70733 (8)	0.0530 (4)
O2	0.46142 (11)	0.1984 (2)	0.63214 (8)	0.0616 (5)
O3	0.37416 (9)	0.2830 (2)	0.85684 (7)	0.0475 (4)
O4	1.04924 (11)	0.1413 (3)	1.20477 (8)	0.0647 (5)
O5	0.92109 (13)	0.1656 (4)	1.27824 (9)	0.1001 (8)
O6	1.00999 (10)	0.2403 (2)	1.05180 (8)	0.0579 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0377 (10)	0.0468 (11)	0.0326 (10)	−0.0036 (9)	0.0012 (8)	−0.0007 (9)
C2	0.0396 (10)	0.0555 (12)	0.0257 (10)	−0.0045 (9)	0.0039 (8)	−0.0019 (8)
C3	0.0331 (10)	0.0523 (12)	0.0288 (10)	−0.0056 (9)	0.0041 (7)	−0.0010 (8)
C4	0.0408 (11)	0.0524 (12)	0.0291 (10)	−0.0054 (9)	0.0040 (8)	−0.0018 (8)
C5	0.0436 (11)	0.0645 (14)	0.0297 (10)	−0.0037 (10)	0.0073 (8)	−0.0076 (9)
C6	0.0375 (11)	0.0636 (14)	0.0386 (11)	0.0016 (10)	0.0050 (9)	−0.0075 (10)
C7	0.0413 (11)	0.0452 (11)	0.0321 (10)	0.0004 (9)	0.0012 (8)	−0.0003 (8)
C8	0.0382 (11)	0.0651 (14)	0.0361 (11)	−0.0038 (10)	0.0045 (9)	0.0048 (9)
C9	0.0461 (11)	0.0623 (14)	0.0297 (10)	−0.0010 (10)	0.0082 (9)	0.0057 (9)
C10	0.0423 (11)	0.0499 (12)	0.0275 (10)	0.0004 (9)	0.0024 (8)	0.0009 (8)
C11	0.0359 (10)	0.0507 (12)	0.0325 (10)	−0.0005 (9)	0.0033 (8)	0.0007 (8)
C12	0.0408 (11)	0.0537 (12)	0.0265 (10)	−0.0002 (9)	0.0034 (8)	0.0027 (8)
C13	0.0401 (11)	0.0553 (12)	0.0304 (10)	−0.0016 (9)	0.0033 (8)	−0.0034 (9)
C14	0.0458 (12)	0.0606 (13)	0.0285 (10)	−0.0015 (10)	0.0050 (9)	0.0032 (9)
C15	0.0452 (12)	0.0891 (18)	0.0356 (12)	−0.0075 (11)	−0.0071 (9)	−0.0099 (11)
C16	0.0470 (12)	0.107 (2)	0.0326 (11)	0.0060 (13)	−0.0046 (9)	0.0061 (12)
C17	0.0433 (12)	0.0973 (19)	0.0350 (11)	0.0075 (12)	0.0059 (9)	−0.0140 (11)
C18	0.0444 (12)	0.1011 (19)	0.0369 (12)	−0.0048 (12)	0.0101 (9)	0.0112 (12)
O1	0.0411 (8)	0.0887 (12)	0.0277 (7)	−0.0117 (7)	−0.0010 (6)	−0.0036 (7)
O2	0.0497 (9)	0.1084 (14)	0.0272 (8)	−0.0051 (8)	0.0067 (6)	−0.0013 (8)
O3	0.0360 (7)	0.0799 (11)	0.0265 (7)	0.0022 (7)	0.0032 (5)	−0.0055 (6)
O4	0.0444 (9)	0.1215 (15)	0.0266 (8)	0.0118 (9)	−0.0011 (6)	0.0045 (8)
O5	0.0544 (10)	0.217 (2)	0.0287 (9)	0.0005 (12)	0.0049 (7)	0.0034 (11)
O6	0.0368 (8)	0.1072 (13)	0.0289 (7)	−0.0093 (8)	0.0018 (6)	0.0119 (8)

Geometric parameters (Å, º) top

C1—C2	1.387 (3)	C12—H12	0.9300
C1—C6	1.394 (3)	C13—O2	1.200 (2)
C1—C7	1.491 (3)	C13—O1	1.329 (2)
C2—C3	1.387 (3)	C14—O5	1.188 (2)
C2—H2	0.9300	C14—O4	1.304 (2)
C3—O3	1.359 (2)	C15—O1	1.447 (2)
C3—C4	1.410 (2)	C15—H15A	0.9600
C4—C5	1.386 (3)	C15—H15B	0.9600
C4—C13	1.494 (3)	C15—H15C	0.9600
C5—C6	1.378 (3)	C16—O4	1.444 (2)
C5—H5	0.9300	C16—H16A	0.9600
C6—H6	0.9300	C16—H16B	0.9600
C7—C12	1.389 (3)	C16—H16C	0.9600
C7—C8	1.393 (3)	C17—O3	1.422 (2)
C8—C9	1.381 (3)	C17—H17A	0.9600
C8—H8	0.9300	C17—H17B	0.9600
C9—C10	1.386 (3)	C17—H17C	0.9600
C9—H9	0.9300	C18—O6	1.426 (2)
C10—C11	1.407 (2)	C18—H18A	0.9600
C10—C14	1.489 (3)	C18—H18B	0.9600
C11—O6	1.359 (2)	C18—H18C	0.9600
C11—C12	1.389 (3)

C2—C1—C6	118.52 (17)	C11—C12—H12	119.2
C2—C1—C7	120.74 (17)	O2—C13—O1	123.42 (17)
C6—C1—C7	120.74 (17)	O2—C13—C4	123.29 (18)
C3—C2—C1	121.67 (17)	O1—C13—C4	113.25 (16)
C3—C2—H2	119.2	O5—C14—O4	121.94 (18)
C1—C2—H2	119.2	O5—C14—C10	123.11 (19)
O3—C3—C2	122.91 (16)	O4—C14—C10	114.95 (16)
O3—C3—C4	117.51 (16)	O1—C15—H15A	109.5
C2—C3—C4	119.56 (17)	O1—C15—H15B	109.5
C5—C4—C3	118.12 (17)	H15A—C15—H15B	109.5
C5—C4—C13	116.23 (16)	O1—C15—H15C	109.5
C3—C4—C13	125.66 (17)	H15A—C15—H15C	109.5
C6—C5—C4	122.01 (18)	H15B—C15—H15C	109.5
C6—C5—H5	119.0	O4—C16—H16A	109.5
C4—C5—H5	119.0	O4—C16—H16B	109.5
C5—C6—C1	120.08 (18)	H16A—C16—H16B	109.5
C5—C6—H6	120.0	O4—C16—H16C	109.5
C1—C6—H6	120.0	H16A—C16—H16C	109.5
C12—C7—C8	118.60 (17)	H16B—C16—H16C	109.5
C12—C7—C1	119.85 (17)	O3—C17—H17A	109.5
C8—C7—C1	121.54 (18)	O3—C17—H17B	109.5
C9—C8—C7	119.84 (18)	H17A—C17—H17B	109.5
C9—C8—H8	120.1	O3—C17—H17C	109.5
C7—C8—H8	120.1	H17A—C17—H17C	109.5
C8—C9—C10	122.39 (17)	H17B—C17—H17C	109.5
C8—C9—H9	118.8	O6—C18—H18A	109.5
C10—C9—H9	118.8	O6—C18—H18B	109.5
C9—C10—C11	117.76 (17)	H18A—C18—H18B	109.5
C9—C10—C14	116.46 (16)	O6—C18—H18C	109.5
C11—C10—C14	125.78 (17)	H18A—C18—H18C	109.5
O6—C11—C12	122.32 (16)	H18B—C18—H18C	109.5
O6—C11—C10	117.80 (16)	C13—O1—C15	115.73 (15)
C12—C11—C10	119.86 (17)	C3—O3—C17	117.41 (14)
C7—C12—C11	121.53 (17)	C14—O4—C16	116.86 (16)
C7—C12—H12	119.2	C11—O6—C18	117.77 (15)

C6—C1—C2—C3	−0.3 (3)	C14—C10—C11—O6	−0.4 (3)
C7—C1—C2—C3	178.88 (18)	C9—C10—C11—C12	0.1 (3)
C1—C2—C3—O3	−175.97 (18)	C14—C10—C11—C12	−179.39 (19)
C1—C2—C3—C4	2.1 (3)	C8—C7—C12—C11	0.9 (3)
O3—C3—C4—C5	175.44 (18)	C1—C7—C12—C11	−179.97 (18)
C2—C3—C4—C5	−2.7 (3)	O6—C11—C12—C7	−179.58 (18)
O3—C3—C4—C13	−4.2 (3)	C10—C11—C12—C7	−0.7 (3)
C2—C3—C4—C13	177.70 (19)	C5—C4—C13—O2	−24.9 (3)
C3—C4—C5—C6	1.6 (3)	C3—C4—C13—O2	154.7 (2)
C13—C4—C5—C6	−178.72 (19)	C5—C4—C13—O1	152.69 (19)
C4—C5—C6—C1	0.1 (3)	C3—C4—C13—O1	−27.7 (3)
C2—C1—C6—C5	−0.8 (3)	C9—C10—C14—O5	−17.9 (3)
C7—C1—C6—C5	−179.99 (19)	C11—C10—C14—O5	161.6 (2)
C2—C1—C7—C12	−150.2 (2)	C9—C10—C14—O4	162.24 (19)
C6—C1—C7—C12	28.9 (3)	C11—C10—C14—O4	−18.3 (3)
C2—C1—C7—C8	28.9 (3)	O2—C13—O1—C15	−1.3 (3)
C6—C1—C7—C8	−152.0 (2)	C4—C13—O1—C15	−178.92 (18)
C12—C7—C8—C9	−0.6 (3)	C2—C3—O3—C17	7.5 (3)
C1—C7—C8—C9	−179.67 (19)	C4—C3—O3—C17	−170.62 (19)
C7—C8—C9—C10	0.0 (3)	O5—C14—O4—C16	−1.3 (4)
C8—C9—C10—C11	0.3 (3)	C10—C14—O4—C16	178.55 (19)
C8—C9—C10—C14	179.8 (2)	C12—C11—O6—C18	−5.2 (3)
C9—C10—C11—O6	179.02 (19)	C10—C11—O6—C18	175.9 (2)

Experimental details

Crystal data
Chemical formula	C₁₈H₁₈O₆
M_r	330.32
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	297
a, b, c (Å)	12.9320 (6), 7.3736 (4), 16.4203 (8)
β (°)	97.410 (2)
V (Å³)	1552.69 (13)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.23 × 0.17 × 0.06

Data collection
Diffractometer	Bruker PHOTON CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.976, 0.994
No. of measured, independent and observed [I > 2σ(I)] reflections	14813, 2830, 2023
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.051, 0.143, 1.02
No. of reflections	2830
No. of parameters	217
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.30, −0.21

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008) and WinGX (Farrugia, 2012), DIAMOND (Brandenburg, 2004) and ChemBioDraw Ultra (CambridgeSoft, 2009), publCIF (Westrip, 2010).

Selected torsion angles (º) top

C2—C1—C7—C8	28.9 (3)	C11—C10—C14—O4	−18.3 (3)
C3—C4—C13—O1	−27.7 (3)

Acknowledgements

We acknowledge the support from the Norwegian Research Council (project 190980), inGAP, RECX and the Department of Chemistry, UiO.

References

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