research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 72| Part 3| March 2016| Pages 328-330

Crystal structure of di­methyl 4,4′-di­meth­­oxy­bi­phenyl-3,3′-di­carboxyl­ate

CROSSMARK_Color_square_no_text.svg

aCentre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, PO Box 1126, 0315 Oslo, Norway, and bDepartment of Chemistry, University of Bergen, PO Box 7803, 5020 Bergen, Norway
*Correspondence e-mail: fredrik.lundvall@smn.uio.no

Edited by M. Weil, Vienna University of Technology, Austria (Received 30 January 2016; accepted 9 February 2016; online 13 February 2016)

In the title compound, C18H18O6, the benzene rings are coplanar due to the centrosymmetric nature of the mol­ecule, with an inversion centre located at the midpoint of the C—C bond between the two rings. Consequently, the methyl carboxyl­ate substituents are oriented in a trans fashion with regards to the bond between the benzene rings. The methyl carboxyl­ate and meth­oxy substituents are rotated slightly out of plane relative to their parent benzene rings, with dihedral and torsion angles of 18.52 (8) and −5.22 (15)°, respectively. The shortest O⋯H contact between neighbouring mol­ecules is about 2.5 Å. Although some structure-directing contributions from C—H⋯O hydrogen-bonding inter­actions are possible, the crystal packing seems primarily directed by weak van der Waals forces.

1. Chemical context

The title compound is an inter­mediate in the synthesis of 4,4′-di­meth­oxy­biphenyl-3,3′-bi­phenyldi­carb­oxy­lic acid, an organic linker for use in the synthesis of coordination polymers (Lundvall et al., 2016[Lundvall, F., Vajeeston, P., Wragg, D. S., Dietzel, P. D. C. & Fjellvåg, H. (2016). Cryst. Growth Des. 16, 339-346.]). The title compound, C18H18O6, has previously been reported (Wang et al., 2009[Wang, L., Xiao, Z.-Y., Hou, J.-L., Wang, G.-T., Jiang, X.-K. & Li, Z. (2009). Tetrahedron, 65, 10544-10551.]; Kar et al., 2009[Kar, A., Mangu, N., Kaiser, H. M. & Tse, M. K. (2009). J. Organomet. Chem. 694, 524-537.]), however, its crystal structure was undetermined up until now.

[Scheme 1]

2. Structural commentary

The asymmetric unit of the title compound comprises one half of the mol­ecule, with an inversion centre located at the midpoint of the benzene–benzene bond (Fig. 1[link]). The benzene rings are coplanar due to symmetry. This is somewhat unexpected since a slight torsion between the two rings is a common feature in biphenyl compounds. The methyl carb­oxyl­ate substituents are oriented trans relative to the benzene–benzene bond, and the plane of the substituent makes a dihedral angle of 18.52 (8)° relative to the parent benzene ring. The meth­oxy substituent is nearly coplanar with the parent benzene ring, and a torsion angle C5—C4—O1—C9 of only −5.22 (15)° is observed. The methyl groups of the methyl carboxyl­ate and meth­oxy substituents are oriented away from each other to accommodate the steric demands of these groups.

[Figure 1]
Figure 1
The mol­ecular structure of the title compound with atom labels and 50% probability displacement ellipsoids. Non-labelled atoms are generated by the symmetry code (−x + [{1\over 2}], −y + [{1\over 2}], −z). H atoms have been omitted for clarity.

3. Supra­molecular features

The mol­ecules are packed in the unit cell with the axis of the biphenyl scaffolds parallel to each other. The axis of the biphenyl moiety is oriented approximately 20° off the a axis of the unit cell (Fig. 2[link]), and the mol­ecules form corrugated layers extending parallel to the ac plane (Fig. 3[link]). The packing is not directed by strong inter­molecular bonding since the shortest O⋯H contact is about 2.5 Å (Table 1[link]). However, weak C—H⋯O inter­actions between neighbouring mol­ecules seem to have an influence on the crystal packing (Fig. 4[link]).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C9—H9C⋯O1i 0.98 2.55 3.4759 (15) 158
C8—H8B⋯O3ii 0.98 2.50 3.3407 (15) 144
Symmetry codes: (i) x, y-1, z; (ii) [-x, y, -z-{\script{1\over 2}}].
[Figure 2]
Figure 2
Packing diagram of the title compound viewed along the b axis.
[Figure 3]
Figure 3
Packing diagram of the title compound viewed along the a axis. H atoms have been omitted for clarity.
[Figure 4]
Figure 4
Graphical representation of the shortest inter­molecular O⋯H contacts, illustrated as dashed blue lines.

4. Synthesis and crystallization

The title compound was synthesized by a slightly modified procedure of the method described by Wang et al. (2009[Wang, L., Xiao, Z.-Y., Hou, J.-L., Wang, G.-T., Jiang, X.-K. & Li, Z. (2009). Tetrahedron, 65, 10544-10551.]). Synthetic details are given in the Supporting Information of our recent contribution (Lundvall et al., 2016[Lundvall, F., Vajeeston, P., Wragg, D. S., Dietzel, P. D. C. & Fjellvåg, H. (2016). Cryst. Growth Des. 16, 339-346.]). Single crystals suitable for structure determination were obtained by recrystallizing the title compound from chloro­form solution.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. H atoms were positioned geom­etrically at distances of 0.95 (CH) and 0.98 Å (CH3) and were refined using a riding model with Uiso(H) = 1.2Ueq(CH) and Uiso(H)=1.5Ueq(CH3).

Table 2
Experimental details

Crystal data
Chemical formula C18H18O6
Mr 330.32
Crystal system, space group Monoclinic, C2/c
Temperature (K) 105
a, b, c (Å) 28.5800 (14), 4.0632 (2), 14.4806 (7)
β (°) 115.100 (1)
V3) 1522.78 (13)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.11
Crystal size (mm) 0.56 × 0.29 × 0.22
 
Data collection
Diffractometer Bruker PHOTON CCD
Absorption correction Multi-scan (SADABS; Bruker, 2007[Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.602, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections 17902, 2053, 1819
Rint 0.037
(sin θ/λ)max−1) 0.685
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.109, 1.10
No. of reflections 2053
No. of parameters 111
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.41, −0.24
Computer programs: APEX2 and SAINT (Bruker, 2007[Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), DIAMOND (Brandenburg, 2004[Brandenburg, K. (2004). DIAMOND. Crystal Impact GbR, Bonn, Germany.]), ChemBioDraw (Cambridge Soft, 2009[Cambridge Soft (2009). ChemBioDraw Ultra. Cambridge Soft Corporation, Cambridge, Massachusetts, USA.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Chemical context top

The title compound is an inter­mediate in the synthesis of 4,4'-di­meth­oxy­biphenyl-3,3'-bi­phenyldi­carb­oxy­lic acid, an organic linker for use in the synthesis of coordination polymers (Lundvall et al., 2016). The title compound, C18H18O6, has previously been reported (Wang et al., 2009; Kar et al., 2009), however, its crystal structure was undetermined up until now.

Structural commentary top

The asymmetric unit of the title compound comprises one half of the molecule, with an inversion centre located at the midpoint of the benzene–benzene bond (Fig. 1). The benzene rings are coplanar due to symmetry. This is somewhat unexpected since a slight torsion between the two rings is a common feature in bi­phenyl compounds. The methyl carboxyl­ate substituents are oriented trans relative to the benzene–benzene bond, and the plane of the substituent makes a dihedral angle of 18.52 (8)° relative to the parent benzene ring. The meth­oxy substituent is nearly coplanar with the parent benzene ring, and a torsion angle C5—C4—O1—C9 of only −5.22 (15)° is observed. The methyl groups of the methyl carboxyl­ate and meth­oxy substituents are oriented away from each other to accommodate the steric demands of these groups.

Supra­molecular features top

The molecules are packed in the unit cell with the axis of the bi­phenyl scaffolds parallel to each other. The axis of the bi­phenyl moiety is oriented approximately 20° off the a axis of the unit cell (Fig. 2), and the molecules form corrugated layers extending parallel to the ac plane (Fig. 3). The packing is not directed by strong inter­molecular bonding since the shortest O···H contact is about 2.5 Å (Table 1). However, weak C—H···O inter­actions between neighbouring molecules seem to have an influence on the crystal packing (Fig. 4).

Synthesis and crystallization top

The title compound was synthesized by a slightly modified procedure of the method described by Wang et al. (2009). Synthetic details are given in the Supporting Information of our recent contribution (Lundvall et al., 2016). Single crystals suitable for XRD analysis were obtained by recrystallizing the title compound from chloro­form.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were positioned geometrically at distances of 0.95 (CH) and 0.98 Å (CH3) and were refined using a riding model with Uiso(H) = 1.2Ueq(CH) and Uiso(H)=1.5Ueq(CH3)

Structure description top

The title compound is an inter­mediate in the synthesis of 4,4'-di­meth­oxy­biphenyl-3,3'-bi­phenyldi­carb­oxy­lic acid, an organic linker for use in the synthesis of coordination polymers (Lundvall et al., 2016). The title compound, C18H18O6, has previously been reported (Wang et al., 2009; Kar et al., 2009), however, its crystal structure was undetermined up until now.

The asymmetric unit of the title compound comprises one half of the molecule, with an inversion centre located at the midpoint of the benzene–benzene bond (Fig. 1). The benzene rings are coplanar due to symmetry. This is somewhat unexpected since a slight torsion between the two rings is a common feature in bi­phenyl compounds. The methyl carboxyl­ate substituents are oriented trans relative to the benzene–benzene bond, and the plane of the substituent makes a dihedral angle of 18.52 (8)° relative to the parent benzene ring. The meth­oxy substituent is nearly coplanar with the parent benzene ring, and a torsion angle C5—C4—O1—C9 of only −5.22 (15)° is observed. The methyl groups of the methyl carboxyl­ate and meth­oxy substituents are oriented away from each other to accommodate the steric demands of these groups.

The molecules are packed in the unit cell with the axis of the bi­phenyl scaffolds parallel to each other. The axis of the bi­phenyl moiety is oriented approximately 20° off the a axis of the unit cell (Fig. 2), and the molecules form corrugated layers extending parallel to the ac plane (Fig. 3). The packing is not directed by strong inter­molecular bonding since the shortest O···H contact is about 2.5 Å (Table 1). However, weak C—H···O inter­actions between neighbouring molecules seem to have an influence on the crystal packing (Fig. 4).

Synthesis and crystallization top

The title compound was synthesized by a slightly modified procedure of the method described by Wang et al. (2009). Synthetic details are given in the Supporting Information of our recent contribution (Lundvall et al., 2016). Single crystals suitable for XRD analysis were obtained by recrystallizing the title compound from chloro­form.

Refinement details top

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were positioned geometrically at distances of 0.95 (CH) and 0.98 Å (CH3) and were refined using a riding model with Uiso(H) = 1.2Ueq(CH) and Uiso(H)=1.5Ueq(CH3)

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015) and WinGX (Farrugia, 2012); molecular graphics: DIAMOND (Brandenburg, 2004) and ChemBioDraw (Cambridge Soft, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with atom labels and 50% probability displacement ellipsoids. Non-labelled atoms are generated by the symmetry code (−x + 1/2, −y + 1/2, −z). H atoms have been omitted for clarity.
[Figure 2] Fig. 2. Packing diagram of the title compound viewed along the b axis.
[Figure 3] Fig. 3. Packing diagram of the title compound viewed along the a axis. H atoms have been omitted for clarity.
[Figure 4] Fig. 4. Graphical representation of the shortest intermolecular O···H contacts, illustrated as dashed blue lines.
Dimethyl 4,4'-dimethoxybiphenyl-3,3'-dicarboxylate top
Crystal data top
C18H18O6F(000) = 696
Mr = 330.32Dx = 1.441 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
a = 28.5800 (14) ÅCell parameters from 9942 reflections
b = 4.0632 (2) Åθ = 2.8–29.1°
c = 14.4806 (7) ŵ = 0.11 mm1
β = 115.100 (1)°T = 105 K
V = 1522.78 (13) Å3Needle, colourless
Z = 40.56 × 0.29 × 0.22 mm
Data collection top
Bruker PHOTON CCD
diffractometer
2053 independent reflections
Radiation source: fine-focus sealed tube1819 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
ω scansθmax = 29.2°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 3838
Tmin = 0.602, Tmax = 0.746k = 55
17902 measured reflectionsl = 1919
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109H-atom parameters constrained
S = 1.10 w = 1/[σ2(Fo2) + (0.0534P)2 + 1.1903P]
where P = (Fo2 + 2Fc2)/3
2053 reflections(Δ/σ)max < 0.001
111 parametersΔρmax = 0.41 e Å3
0 restraintsΔρmin = 0.24 e Å3
Crystal data top
C18H18O6V = 1522.78 (13) Å3
Mr = 330.32Z = 4
Monoclinic, C2/cMo Kα radiation
a = 28.5800 (14) ŵ = 0.11 mm1
b = 4.0632 (2) ÅT = 105 K
c = 14.4806 (7) Å0.56 × 0.29 × 0.22 mm
β = 115.100 (1)°
Data collection top
Bruker PHOTON CCD
diffractometer
2053 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
1819 reflections with I > 2σ(I)
Tmin = 0.602, Tmax = 0.746Rint = 0.037
17902 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.109H-atom parameters constrained
S = 1.10Δρmax = 0.41 e Å3
2053 reflectionsΔρmin = 0.24 e Å3
111 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.22923 (4)0.2306 (3)0.01755 (7)0.0163 (2)
C20.17986 (4)0.3583 (3)0.03782 (7)0.0175 (2)
H20.17300.47030.09980.021*
C30.14011 (4)0.3300 (3)0.00694 (7)0.0170 (2)
C40.14924 (4)0.1625 (3)0.08424 (8)0.0170 (2)
C50.19832 (4)0.0299 (3)0.14041 (8)0.0193 (2)
H50.20520.08510.20200.023*
C60.23708 (4)0.0637 (3)0.10753 (8)0.0193 (2)
H60.27010.02930.14730.023*
C70.09039 (4)0.4858 (3)0.07720 (8)0.0192 (2)
C80.01027 (4)0.7077 (3)0.10223 (9)0.0256 (3)
H8A0.01110.74540.06530.038*
H8B0.00860.56850.16180.038*
H8C0.01840.91910.12460.038*
C90.11816 (5)0.0599 (3)0.20034 (8)0.0229 (2)
H9A0.08680.05860.21210.034*
H9B0.14700.03090.26010.034*
H9C0.12620.28630.18880.034*
O10.10999 (3)0.1361 (2)0.11283 (6)0.02064 (19)
O20.05778 (3)0.5450 (2)0.03563 (6)0.0232 (2)
O30.08127 (3)0.5572 (3)0.16406 (7)0.0354 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0173 (5)0.0161 (5)0.0141 (4)0.0009 (4)0.0053 (4)0.0023 (4)
C20.0182 (5)0.0194 (5)0.0133 (4)0.0012 (4)0.0051 (4)0.0004 (4)
C30.0162 (4)0.0181 (5)0.0142 (4)0.0010 (4)0.0040 (4)0.0018 (4)
C40.0187 (5)0.0168 (5)0.0156 (4)0.0020 (4)0.0072 (4)0.0027 (4)
C50.0216 (5)0.0201 (5)0.0153 (4)0.0013 (4)0.0071 (4)0.0023 (4)
C60.0186 (5)0.0208 (5)0.0164 (5)0.0025 (4)0.0054 (4)0.0008 (4)
C70.0165 (5)0.0223 (5)0.0170 (5)0.0015 (4)0.0055 (4)0.0001 (4)
C80.0185 (5)0.0324 (6)0.0240 (5)0.0064 (5)0.0073 (4)0.0036 (5)
C90.0288 (6)0.0234 (6)0.0203 (5)0.0022 (4)0.0141 (4)0.0036 (4)
O10.0207 (4)0.0247 (4)0.0184 (4)0.0013 (3)0.0101 (3)0.0038 (3)
O20.0193 (4)0.0323 (5)0.0172 (4)0.0060 (3)0.0068 (3)0.0015 (3)
O30.0223 (4)0.0622 (7)0.0219 (4)0.0115 (4)0.0096 (3)0.0158 (4)
Geometric parameters (Å, º) top
C1—C21.3940 (14)C6—H60.9500
C1—C61.3998 (14)C7—O31.2067 (14)
C1—C1i1.4846 (19)C7—O21.3285 (13)
C2—C31.3909 (14)C8—O21.4490 (13)
C2—H20.9500C8—H8A0.9800
C3—C41.4080 (14)C8—H8B0.9800
C3—C71.4928 (14)C8—H8C0.9800
C4—O11.3549 (12)C9—O11.4293 (13)
C4—C51.3971 (15)C9—H9A0.9800
C5—C61.3859 (15)C9—H9B0.9800
C5—H50.9500C9—H9C0.9800
C2—C1—C6116.04 (9)O3—C7—O2123.09 (10)
C2—C1—C1i121.65 (11)O3—C7—C3122.32 (10)
C6—C1—C1i122.31 (11)O2—C7—C3114.58 (9)
C3—C2—C1123.36 (9)O2—C8—H8A109.5
C3—C2—H2118.3O2—C8—H8B109.5
C1—C2—H2118.3H8A—C8—H8B109.5
C2—C3—C4119.32 (9)O2—C8—H8C109.5
C2—C3—C7114.66 (9)H8A—C8—H8C109.5
C4—C3—C7126.03 (9)H8B—C8—H8C109.5
O1—C4—C5123.27 (9)O1—C9—H9A109.5
O1—C4—C3118.48 (9)O1—C9—H9B109.5
C5—C4—C3118.25 (10)H9A—C9—H9B109.5
C6—C5—C4120.87 (10)O1—C9—H9C109.5
C6—C5—H5119.6H9A—C9—H9C109.5
C4—C5—H5119.6H9B—C9—H9C109.5
C5—C6—C1122.15 (10)C4—O1—C9118.03 (8)
C5—C6—H6118.9C7—O2—C8114.87 (9)
C1—C6—H6118.9
C6—C1—C2—C30.89 (16)C2—C1—C6—C50.64 (16)
C1i—C1—C2—C3179.29 (11)C1i—C1—C6—C5179.55 (12)
C1—C2—C3—C40.55 (16)C2—C3—C7—O317.33 (16)
C1—C2—C3—C7179.71 (10)C4—C3—C7—O3162.39 (12)
C2—C3—C4—O1179.68 (9)C2—C3—C7—O2161.30 (10)
C7—C3—C4—O10.03 (16)C4—C3—C7—O218.97 (16)
C2—C3—C4—C50.08 (15)C5—C4—O1—C95.22 (15)
C7—C3—C4—C5179.63 (10)C3—C4—O1—C9174.36 (10)
O1—C4—C5—C6179.90 (10)O3—C7—O2—C80.89 (17)
C3—C4—C5—C60.32 (16)C3—C7—O2—C8177.74 (10)
C4—C5—C6—C10.05 (17)C2—C1—C1i—C6i0.2 (2)
Symmetry code: (i) x+1/2, y+1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9C···O1ii0.982.553.4759 (15)158
C8—H8B···O3iii0.982.503.3407 (15)144
Symmetry codes: (ii) x, y1, z; (iii) x, y, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9C···O1i0.982.553.4759 (15)157.7
C8—H8B···O3ii0.982.503.3407 (15)144.2
Symmetry codes: (i) x, y1, z; (ii) x, y, z1/2.

Experimental details

Crystal data
Chemical formulaC18H18O6
Mr330.32
Crystal system, space groupMonoclinic, C2/c
Temperature (K)105
a, b, c (Å)28.5800 (14), 4.0632 (2), 14.4806 (7)
β (°) 115.100 (1)
V3)1522.78 (13)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.56 × 0.29 × 0.22
Data collection
DiffractometerBruker PHOTON CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2007)
Tmin, Tmax0.602, 0.746
No. of measured, independent and
observed [I > 2σ(I)] reflections
17902, 2053, 1819
Rint0.037
(sin θ/λ)max1)0.685
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.109, 1.10
No. of reflections2053
No. of parameters111
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.41, 0.24

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL2014 (Sheldrick, 2015) and WinGX (Farrugia, 2012), DIAMOND (Brandenburg, 2004) and ChemBioDraw (Cambridge Soft, 2009), publCIF (Westrip, 2010).

 

Acknowledgements

We acknowledge support from the Research Council of Norway (Project No. 190980), the Norwegian national infrastructure for X-ray diffraction and scattering (RECX) and the Department of Chemistry, UiO.

References

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COMMUNICATIONS
ISSN: 2056-9890
Volume 72| Part 3| March 2016| Pages 328-330
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